Programs & Examples On #Restrict

AngularJs directive not updating another directive's scope

Just wondering why you are using 2 directives?

It seems like, in this case it would be more straightforward to have a controller as the parent - handle adding the data from your service to its $scope, and pass the model you need from there into your warrantyDirective.

Or for that matter, you could use 0 directives to achieve the same result. (ie. move all functionality out of the separate directives and into a single controller).

It doesn't look like you're doing any explicit DOM transformation here, so in this case, perhaps using 2 directives is overcomplicating things.

Alternatively, have a look at the Angular documentation for directives: The very last example at the bottom of the page explains how to wire up dependent directives.

Empty brackets '[]' appearing when using .where

Stuarts' answer is correct, but if you are not sure if you are saving the titles in lowercase, you can also make a case insensitive search

There are a lot of answered questions in Stack Overflow with more data on this:

Example 1

Example 2

GoogleMaps API KEY for testing

There seems no way to have google maps api key free without credit card. To test the functionality of google map you can use it while leaving the api key field "EMPTY". It will show a message saying "For Development Purpose Only". And that way you can test google map functionality without putting billing information for google map api key.

<script src="" async defer></script>

Couldn't process file resx due to its being in the Internet or Restricted zone or having the mark of the web on the file

  1. Open the file explorer. Navigate to project/solution directory
  2. Search for *.resx. --> You will get list of resx files
  3. Right click the resx file, open the properties and check the option 'Unblock'
  4. Repeat #3 for each resx file.
  5. Reload the project.

Reading images in python

If you just want to read an image in Python using the specified libraries only, I will go with matplotlib

In matplotlib :

import matplotlib.image
read_img = matplotlib.image.imread('your_image.png')

INSTALL_FAILED_USER_RESTRICTED : android studio using redmi 4 device

Settings->Additional Settings->Developer Options

1) Turn ON Developer Options
2) Turn ON USB Debugging
3) Turn OFF MIUI optimization
4) Turn ON Install via USB

Cordova app not displaying correctly on iPhone X (Simulator)

I'm developing cordova apps for 2 years and I spent weeks to solve related problems (eg: webview scrolls when keyboard open). Here's a tested and proven solution for both ios and android

P.S.: I'm using iScroll for scrolling content

  1. Never use viewport-fit=cover at index.html's meta tag, leave the app stay out of statusbar. iOS will handle proper area for all iPhone variants.
  2. In XCode uncheck hide status bar and requires full screen and don't forget to select Launch Screen File as CDVLaunchScreen
  3. In config.xml set fullscreen as false
  4. Finally, (thanks to Eddy Verbruggen for great plugins) add his plugin cordova-plugin-webviewcolor to set statusbar and bottom area background color. This plugin will allow you to set any color you want.
  5. Add below to config.xml (first ff after x is opacity)

    <preference name="BackgroundColor" value="0xff088c90" />
  6. Handle your scroll position yourself by adding focus events to input elements

    iscrollObj.scrollToElement(elm, transitionduration ... etc)

For android, do the same but instead of cordova-plugin-webviewcolor, install cordova-plugin-statusbar and cordova-plugin-navigationbar-color

Here's a javascript code using those plugins to work on both ios and android:

function setStatusColor(colorCode) {
    //colorCode is smtg like '#427309';
    if (cordova.platformId == 'android') {
    } else if (cordova.platformId == 'ios') {

No restricted globals

Use react-router-dom library.

From there, import useLocation hook if you're using functional components:

import { useLocation } from 'react-router-dom';

Then append it to a variable:

Const location = useLocation();

You can then use it normally:


P.S: the returned location object has five properties only:

{ hash: "", key: "", pathname: "/" search: "", state: undefined__, }

How to assign more memory to docker container

That 2GB limit you see is the total memory of the VM in which docker runs.

If you are using docker-for-windows or docker-for-mac you can easily increase it from the Whale icon in the task bar, then go to Preferences -> Advanced:

Docker Preferences

But if you are using VirtualBox behind, open VirtualBox, Select and configure the docker-machine assigned memory.

See this for Mac:

MEMORY By default, Docker for Mac is set to use 2 GB runtime memory, allocated from the total available memory on your Mac. You can increase the RAM on the app to get faster performance by setting this number higher (for example to 3) or lower (to 1) if you want Docker for Mac to use less memory.

For Windows:

Memory - Change the amount of memory the Docker for Windows Linux VM uses

Context.startForegroundService() did not then call Service.startForeground()

I have fixed the problem with starting the service with startService(intent) instead of Context.startForeground() and calling startForegound() immediately after super.OnCreate(). Additionally, if you starting service on boot, you can start Activity that starts service on the boot broadcast. Although it is not a permanent solution, it works.

The create-react-app imports restriction outside of src directory

There are a few answers that provide solutions with react-app-rewired, but customize-cra exposes a special removeModuleScopePlugin() API which is a bit more elegant. (It's the same solution, but abstracted away by the customize-cra package.)

npm i --save-dev react-app-rewired customize-cra


"scripts": {
    - "start": "react-scripts start"
    + "start": "react-app-rewired start",


const { removeModuleScopePlugin } = require('customize-cra')

module.exports = removeModuleScopePlugin()

MongoDB: Server has startup warnings ''Access control is not enabled for the database''

You need to delete your old db folder and recreate new one. It will resolve your issue.

ps1 cannot be loaded because running scripts is disabled on this system

Open powershell in administrative mode and run the following command

Set-ExecutionPolicy RemoteSigned

How to install a Notepad++ plugin offline?

In v7.7, I had to go to Plugins menu and select "Open Plugins Folder..." (which goes to C:\Program Files\Notepad++\plugins).

I had to create a folder for the plugin and extract the .dll into the folder. For example, create a folder called "JSMinNPP" and place the "JSMinNPP.dll" in that folder. It doesn't work if you put the dll into the plugins folder.

Finally go to Settings --> Import --> Import plugin(s) and import that dll and restart Notepad++.

WARNING: sanitizing unsafe style value url

I got the same issue while adding dynamic url in Image tag in Angular 7. I searched a lot and found this solution.

First, write below code in the component file.

constructor(private sanitizer: DomSanitizer) {}
public getSantizeUrl(url : string) {
    return this.sanitizer.bypassSecurityTrustUrl(url);

Now in your html image tag, you can write like this.

<img class="image-holder" [src]=getSantizeUrl(item.imageUrl) />

You can write as per your requirement instead of item.imageUrl

I got a reference from this site.dynamic urls. Hope this solution will help you :)

How to get current available GPUs in tensorflow?

There is an undocumented method called device_lib.list_local_devices() that enables you to list the devices available in the local process. (N.B. As an undocumented method, this is subject to backwards incompatible changes.) The function returns a list of DeviceAttributes protocol buffer objects. You can extract a list of string device names for the GPU devices as follows:

from tensorflow.python.client import device_lib

def get_available_gpus():
    local_device_protos = device_lib.list_local_devices()
    return [ for x in local_device_protos if x.device_type == 'GPU']

Note that (at least up to TensorFlow 1.4), calling device_lib.list_local_devices() will run some initialization code that, by default, will allocate all of the GPU memory on all of the devices (GitHub issue). To avoid this, first create a session with an explicitly small per_process_gpu_fraction, or allow_growth=True, to prevent all of the memory being allocated. See this question for more details.

iOS 10: "[App] if we're in the real pre-commit handler we can't actually add any new fences due to CA restriction"

We can mute it in this way (device and simulator need different values):

Add the Name OS_ACTIVITY_MODE and the Value ${DEBUG_ACTIVITY_MODE} and check it (in Product -> Scheme -> Edit Scheme -> Run -> Arguments -> Environment).

enter image description here

Add User-Defined Setting DEBUG_ACTIVITY_MODE, then add Any iOS Simulator SDK for Debug and set it's value to disable (in Project -> Build settings -> + -> User-Defined Setting)

enter image description here

Angular 2 Date Input not binding to date value

use DatePipe

> // ts file

import { DatePipe } from '@angular/common';


export class FormComponent {

constructor(private datePipe : DatePipe){}

    demoUser = new User(0, '', '', '', '', this.datePipe.transform(new Date(), 'yyyy-MM-dd'), '', 0, [], []);  

Use of symbols '@', '&', '=' and '>' in custom directive's scope binding: AngularJS

> is not in the documentation.

< is for one-way binding.

@ binding is for passing strings. These strings support {{}} expressions for interpolated values.

= binding is for two-way model binding. The model in parent scope is linked to the model in the directive's isolated scope.

& binding is for passing a method into your directive's scope so that it can be called within your directive.

When we are setting scope: true in directive, Angular js will create a new scope for that directive. That means any changes made to the directive scope will not reflect back in parent controller.

Proper way to restrict text input values (e.g. only numbers)

Anoher one

<form [formGroup]="myForm" novalidate>
    <input type="text" class="form-control" id="data" name="data"
           formControlName="input3" #item (input)="change(item.value)">
{{myForm.value |json}}

    let lastchar = value.substr(value.length - 1);
    if (!(new RegExp('[0-9]').test(lastchar)))


if you use from driven template

  <input type="text" class="form-control" id="data" name="data"
       [(ngModel)]="data" #item (input)="change(item)">

    let value=item.value;
    let lastchar = value.substr(value.length - 1);
    if (!(new RegExp('[0-9]').test(lastchar)))

Update As @BikashBishwokarma comment, this not work if you insert a character in middle. We can change the function by some like

    let value=item.value;
    let pos=item.selectionStart;
    if (!(new RegExp('^[0-9]+$').test(value)))
    {[^0-9]+/g, '');
      item.selectionStart = item.selectionEnd = pos-1;

See, how mainten the cursor position

Send FormData with other field in AngularJS

Here is the complete solution

html code,

create the text anf file upload fields as shown below

    <div class="form-group">
            <label for="usr">User Name:</label>
            <input type="text" id="usr" ng-model="model.username">
            <label for="pwd">Password:</label>
            <input type="password" id="pwd" ng-model="model.password">
            <div class="col-lg-6">
                <input type="file" file-model="model.somefile"/>

            <label for="dob">Dob:</label>
            <input type="date" id="dob" ng-model="model.dob">
            <label for="email">Email:</label>
            <input type="email"id="email" ng-model="">

        <button type="submit" ng-click="saveData(model)" >Submit</button>

directive code

create a filemodel directive to parse file

.directive('fileModel', ['$parse', function ($parse) {
return {
    restrict: 'A',
    link: function(scope, element, attrs) {
        var model = $parse(attrs.fileModel);
        var modelSetter = model.assign;

        element.bind('change', function(){
                modelSetter(scope, element[0].files[0]);

Service code

append the file and fields to form data and do $ as shown below remember to keep 'Content-Type': undefined

 .service('fileUploadService', ['$http', function ($http) {
    this.uploadFileToUrl = function(file, username, password, dob, email, uploadUrl){
        var myFormData = new FormData();

        myFormData.append('file', file);
        myFormData.append('username', username);
        myFormData.append('password', password);
        myFormData.append('dob', dob);
        myFormData.append('email', email);

        $, myFormData, {
            transformRequest: angular.identity,
            headers: {'Content-Type': undefined}


In controller

Now in controller call the service by sending required data to be appended in parameters,

$scope.saveData  = function(model){
    var file = model.myFile;
    var uploadUrl = "/api/createUsers";
    fileUpload.uploadFileToUrl(file, model.username, model.password, model.dob,, uploadUrl);

WooCommerce: Finding the products in database

Update 2020

Products are located mainly in the following tables:

  • wp_posts table with post_type like product (or product_variation),

  • wp_postmeta table with post_id as relational index (the product ID).

  • wp_wc_product_meta_lookup table with product_id as relational index (the post ID) | Allow fast queries on specific product data (since WooCommerce 3.7)

  • wp_wc_order_product_lookuptable with product_id as relational index (the post ID) | Allow fast queries to retrieve products on orders (since WooCommerce 3.7)

Product types, categories, subcategories, tags, attributes and all other custom taxonomies are located in the following tables:

  • wp_terms

  • wp_termmeta

  • wp_term_taxonomy

  • wp_term_relationships - column object_id as relational index (the product ID)

  • wp_woocommerce_termmeta

  • wp_woocommerce_attribute_taxonomies (for product attributes only)

  • wp_wc_category_lookup (for product categories hierarchy only since WooCommerce 3.7)

Product types are handled by custom taxonomy product_type with the following default terms:

  • simple
  • grouped
  • variable
  • external

Some other product types for Subscriptions and Bookings plugins:

  • subscription
  • variable-subscription
  • booking

Since Woocommerce 3+ a new custom taxonomy named product_visibility handle:

  • The product visibility with the terms exclude-from-search and exclude-from-catalog
  • The feature products with the term featured
  • The stock status with the term outofstock
  • The rating system with terms from rated-1 to rated-5

Particular feature: Each product attribute is a custom taxonomy…


Access Tomcat Manager App from different host

Following two configuration is working for me.

1 .tomcat-users.xml details
  <role rolename="manager-gui"/>
  <role rolename="manager-script"/>
  <role rolename="manager-jmx"/>
  <role rolename="manager-status"/>
  <role rolename="admin-gui"/>
  <role rolename="admin-script"/>
  <role rolename="tomcat"/>

  <user  username="tomcat"  password="tomcat" roles="tomcat"/>

  <user  username="admin"  password="admin" roles="admin-gui"/>

  <user  username="adminscript"  password="adminscrip" roles="admin-script"/>

  <user  username="tomcat"  password="s3cret" roles="manager-gui"/>
  <user  username="status"  password="status" roles="manager-status"/>

  <user  username="both"    password="both"   roles="manager-gui,manager-status"/>

  <user  username="script"  password="script" roles="manager-script"/>
  <user  username="jmx"     password="jmx"    roles="manager-jmx"/>

2. context.xml  of <tomcat>/webapps/manager/META-INF/context.xml and 
<Context antiResourceLocking="false" privileged="true" >

  <Valve className="org.apache.catalina.valves.RemoteAddrValve"
         allow=".*" />
  <Manager sessionAttributeValueClassNameFilter="java\.lang\.(?:Boolean|Integer|Long|Number|String)|org\.apache\.catalina\.filters\.CsrfPreventionFilter\$LruCache(?:\$1)?|java\.util\.(?:Linked)?HashMap"/>

npm install error - unable to get local issuer certificate

A disclaimer: This solution is less secure, bad practice, don't do this. I had a duplicate error message--I'm behind a corporate VPN/firewall. I was able to resolve this issue by adding a .typingsrc file to my user directory (C:\Users\MyUserName\.typingsrc in windows). Of course, anytime you're circumventing SSL you should be yapping to your sys admins to fix the certificate issue.

Change the registry URL from https to http, and as seen in nfiles' answser above, set rejectUnauthorized to false.

.typingsrc (placed in project directory or in user root directory)

     "rejectUnauthorized": false,
     "registryURL": ""

Optionally add your github token (I didn't find success until I had added this too.)

    "rejectUnauthorized": false,
    "registryURL": "",
    "githubToken": "YourGitHubToken"

See instructions for setting up your github token at

Multiple conditions in an IF statement in Excel VBA

In VBA we can not use if jj = 5 or 6 then we must use if jj = 5 or jj = 6 then

maybe this:

If inputWks.Range("d9") > 0 And (inputWks.Range("d11") = "Restricted_Expenditure" Or inputWks.Range("d11") = "Unrestricted_Expenditure") Then

Allow 2 decimal places in <input type="number">

Step 1: Hook your HTML number input box to an onchange event

myHTMLNumberInput.onchange = setTwoNumberDecimal;

or in the HTML code

<input type="number" onchange="setTwoNumberDecimal" min="0" max="10" step="0.25" value="0.00" />

Step 2: Write the setTwoDecimalPlace method

function setTwoNumberDecimal(event) {
    this.value = parseFloat(this.value).toFixed(2);

You can alter the number of decimal places by varying the value passed into the toFixed() method. See MDN docs.

toFixed(2); // 2 decimal places
toFixed(4); // 4 decimal places
toFixed(0); // integer

Content type 'application/x-www-form-urlencoded;charset=UTF-8' not supported for @RequestBody MultiValueMap

In Spring 5

@PostMapping( "some/request/path" )
public void someControllerMethod( @RequestParam MultiValueMap body ) {

    // import org.springframework.util.MultiValueMap;

    String datax = (String) body .getFirst("datax");

mysqld: Can't change dir to data. Server doesn't start

If you installed MySQL Server using the Windows installer and as a Window's service, then you can start MySQL Server using PowerShell and experience the convenience of not leaving the command line.

Open PowerShell and run the following command:

Get-Service *sql*

A list of MySQL services will be retrieved and displayed. Choose the one that you want and run the following command while replacing service-name with the actual service name:

Start-Service -Name service-name

Done. You can check that the service is running by running the command Get-Service *sql* again and checking the status of the service.

HTML input time in 24 format

You can't do it with the HTML5 input type. There are many libs available to do it, you can use momentjs or some other jQuery UI components for the best outcome.

Google maps Marker Label with multiple characters

First of all, Thanks to code author!

I found the below link while googling and it is very simple and works best. Would never fail unless SVG is deprecated.

There is some js loading error in the code here but its perfectly working on the link provided.

var mapOptions = {_x000D_
    zoom: 16,_x000D_
    center: new google.maps.LatLng(-37.808846, 144.963435)_x000D_
  map = new google.maps.Map(document.getElementById('map-canvas'),_x000D_
var pinz = [_x000D_
            'lat' : -37.807817,_x000D_
            'lon' : 144.958377_x000D_
        'lable' : 2_x000D_
            'lat' : -37.807885,_x000D_
            'lon' : 144.965415_x000D_
        'lable' : 42_x000D_
            'lat' : -37.811377,_x000D_
            'lon' : 144.956596_x000D_
        'lable' : 87_x000D_
            'lat' : -37.811293,_x000D_
            'lon' : 144.962883_x000D_
        'lable' : 145_x000D_
            'lat' : -37.808089,_x000D_
            'lon' : 144.962089_x000D_
        'lable' : 999_x000D_
for(var i = 0; i <= pinz.length; i++){_x000D_
   var image = 'data:image/svg+xml,' + pinz[i].lable + '%3C%2Ftext%3E%3C%2Fsvg%3E';_x000D_
   var myLatLng = new google.maps.LatLng(pinz[i], pinz[i].location.lon);_x000D_
   var marker = new google.maps.Marker({_x000D_
      position: myLatLng,_x000D_
      map: map,_x000D_
      icon: image_x000D_
html, body, #map-canvas {_x000D_
  height: 100%;_x000D_
  margin: 0px;_x000D_
  padding: 0px_x000D_
<div id="map-canvas"></div>_x000D_
<script async defer src=",places"></script>

You just need to uri-encode your SVG html and replace the one in the image variable after "data:image/svg+xml" in the for loop.

For uri encoding you can use uri-encoder-decoder

You can decode the existing svg code first to get a better understanding of what is written.

The target principal name is incorrect. Cannot generate SSPI context

Seems to be issue is related to DNS Server. To resolve this issue change the IP Address to ComputerName.

Example: Change the value "\TestDB" to "YourcomputerName\TestDB"

AngularJS $watch window resize inside directive

// Following is angular 2.0 directive for window re size that adjust scroll bar for give element as per your tag

---- angular 2.0 window resize directive.
import { Directive, ElementRef} from 'angular2/core';

       selector: '[resize]',
       host: { '(window:resize)': 'onResize()' } // Window resize listener

export class AutoResize {

element: ElementRef; // Element that associated to attribute.
$window: any;
       constructor(_element: ElementRef) {

         this.element = _element;
         // Get instance of DOM window.
         this.$window = angular.element(window);



    // Adjust height of element.
    onResize() {
         $(this.element.nativeElement).css('height', (this.$window.height() - 163) + 'px');

Eclipse: How to install a plugin manually?

You can try this

click Help>Install New Software on the menu bar

enter image description here

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How to restrict UITextField to take only numbers in Swift?

Swift 2.0

For only allowing numbers and one "." decimal in uitextfield.

func textField(textField: UITextField,shouldChangeCharactersInRange range: NSRange,replacementString string: String) -> Bool
    let newCharacters = NSCharacterSet(charactersInString: string)
    let boolIsNumber = NSCharacterSet.decimalDigitCharacterSet().isSupersetOfSet(newCharacters)
    if boolIsNumber == true {
        return true
    } else {
        if string == "." {
            let countdots = textField.text!.componentsSeparatedByString(".").count - 1
            if countdots == 0 {
                return true
            } else {
                if countdots > 0 && string == "." {
                    return false
                } else {
                    return true
        } else {
            return false

Sending cookies with postman

You can enable Interceptor in browser and in Postman separately. For send/recieve cookies you should enable Interceptor in Postman. So if you enable interceptor only in browser - it will not work. Actually you don't need enable Interceptor in browser at all - if you don't want to flood your postman history with unnecessary requests.

Ubuntu apt-get unable to fetch packages

I tried using :

sudo do-release-upgrade

and then use :

sudo apt-get update

after that you will be able to install any packages.

If this did not worked for you try to change the network conf in apt.conf

AngularJS Error: Cross origin requests are only supported for protocol schemes: http, data, chrome-extension, https

If for whatever reason you cannot have the files hosted from a webserver and still need some sort of way of loading partials, you can resort to using the ngTemplate directive.

This way, you can include your markup inside script tags in your index.html file and not have to include the markup as part of the actual directive.

Add this to your index.html

<script type='text/ng-template' id='tpl-productColour'>
 <div class="list-group-item">
    <h3>Hello <em class="pull-right">Brother</em></h3>

Then, in your directive:

app.directive('productColor', function() {
      return {
          restrict: 'E', //Element Directive
          //template: 'tpl-productColour'
          templateUrl: 'tpl-productColour'

You cannot call a method on a null-valued expression

The simple answer for this one is that you have an undeclared (null) variable. In this case it is $md5. From the comment you put this needed to be declared elsewhere in your code

$md5 = new-object -TypeName System.Security.Cryptography.MD5CryptoServiceProvider

The error was because you are trying to execute a method that does not exist.

PS C:\Users\Matt> $md5 | gm

   TypeName: System.Security.Cryptography.MD5CryptoServiceProvider

Name                       MemberType Definition                                                                                                                            
----                       ---------- ----------                                                                                                                            
Clear                      Method     void Clear()                                                                                                                          
ComputeHash                Method     byte[] ComputeHash(System.IO.Stream inputStream), byte[] ComputeHash(byte[] buffer), byte[] ComputeHash(byte[] buffer, int offset, ...

The .ComputeHash() of $md5.ComputeHash() was the null valued expression. Typing in gibberish would create the same effect.

PS C:\Users\Matt> $bagel.MakeMeABagel()
You cannot call a method on a null-valued expression.
At line:1 char:1
+ $bagel.MakeMeABagel()
+ ~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
    + FullyQualifiedErrorId : InvokeMethodOnNull

PowerShell by default allows this to happen as defined its StrictMode

When Set-StrictMode is off, uninitialized variables (Version 1) are assumed to have a value of 0 (zero) or $Null, depending on type. References to non-existent properties return $Null, and the results of function syntax that is not valid vary with the error. Unnamed variables are not permitted.

Simple Popup by using Angular JS

If you are using bootstrap.js then the below code might be useful. This is very simple. Dont have to write anything in js to invoke the pop-up.

Source :

<!DOCTYPE html>
<html lang="en">
  <title>Bootstrap Example</title>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="">
  <script src=""></script>
  <script src=""></script>

<div class="container">
  <h2>Modal Example</h2>
  <!-- Trigger the modal with a button -->
  <button type="button" class="btn btn-info btn-lg" data-toggle="modal" data-target="#myModal">Open Modal</button>

  <!-- Modal -->
  <div class="modal fade" id="myModal" role="dialog">
    <div class="modal-dialog">

      <!-- Modal content-->
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Modal Header</h4>
        <div class="modal-body">
          <p>Some text in the modal.</p>
        <div class="modal-footer">
          <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>




Calculate days between two Dates in Java 8

You can use until():

LocalDate independenceDay = LocalDate.of(2014, Month.JULY, 4);
LocalDate christmas = LocalDate.of(2014, Month.DECEMBER, 25);

System.out.println("Until christmas: " + independenceDay.until(christmas));
System.out.println("Until christmas (with crono): " + independenceDay.until(christmas, ChronoUnit.DAYS));

$rootScope.$broadcast vs. $scope.$emit

I made the following graphic out of the following link:

Scope, rootScope, emit, broadcast

As you can see, $rootScope.$broadcast hits a lot more listeners than $scope.$emit.

Also, $scope.$emit's bubbling effect can be cancelled, whereas $rootScope.$broadcast cannot.

Multiple scenarios @RequestMapping produces JSON/XML together with Accept or ResponseEntity

I've preferred using the params filter for parameter-centric content-type.. I believe that should work in conjunction with the produces attribute.

public ResponseEntity<Person> getPerson(@PathVariable Integer id){
    Person person = personMapRepository.findPerson(id);
    return ResponseEntity.ok(person);
public ResponseEntity<Person> getPersonXML(@PathVariable Integer id){
    return GetPerson(id); // delegate

Angularjs - Pass argument to directive

Here is how I solved my problem:


app.directive("directive_name", function(){
    return {
        restrict: 'E',
        transclude: true,
        template: function(elem, attr){
           return '<div><h2>{{'+attr.scope+'}}</h2></div>';
        replace: true


$scope.building = function(data){
    var chart = angular.element(document.createElement('directive_name'));
    chart.attr('scope', data);

I now can use different scopes through the same directive and append them dynamically.

How to work on UAC when installing XAMPP

This is a specific issue for Windows Vista, 7, 8 (and presumably newer).

User Account Control (UAC) is a feature in Windows that can help you stay in control of your computer by informing you when a program makes a change that requires administrator-level permission. UAC works by adjusting the permission level of your user account.

This is applied mostly to C:\Program Files. You may have noticed sometimes, that some applications can see files in C:\Program Files that does not exist there. You know why? Windows now tend to have "C:\Program Files" folder customized for every user. For example, old applications store config files (like .ini) in the same folder where the executable files are stored. In the good old days all users had the same configurations for such apps. In nowadays Windows stores configs in the special folder tied to the user account. Thus, now different users may have different configs while application still think that config files are in the same folder with the executables.

XAMPP does not like to have different config for different users. In fact it is not a config file for XAMPP, it is folders where you keep your projects and databases. The idea of XAMPP is to make projects same for all users. This is a source of a conflict with Windows.

All you need is to avoid installing XAMPP into C:\Program Files. Thus XAMPP will always use the original files for all users and there would be no confusion.

I recommend to install XAMPP into the special folder in root directory like in C:\XAMPP. But before you choose the folder you need to click on this warning message.

XAMPP installation on Win 8.1 with UAC Warning

I have faced the same issue when I tried to install xampp on windows 8.1. The problem in my system was there was no password for the current logged in user account. After creating the password then I tried to install xampp. It installed without any issue. Hope it helps someone in the feature.

No found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations:

I added @Service before impl class and the error is gone.

public class FCSPAnalysisImpl implements FCSPAnalysis

Set element focus in angular way

I like to avoid DOM lookups, watches, and global emitters whenever possible, so I use a more direct approach. Use a directive to assign a simple function that focuses on the directive element. Then call that function wherever needed within the scope of the controller.

Here's a simplified approach for attaching it to scope. See the full snippet for handling controller-as syntax.


app.directive('inputFocusFunction', function () {
    'use strict';
    return {
        restrict: 'A',
        link: function (scope, element, attr) {
            scope[attr.inputFocusFunction] = function () {

and in html:

<input input-focus-function="focusOnSaveInput" ng-model="saveName">
<button ng-click="focusOnSaveInput()">Focus</button>

or in the controller:


angular.module('app', [])_x000D_
  .directive('inputFocusFunction', function() {_x000D_
    'use strict';_x000D_
    return {_x000D_
      restrict: 'A',_x000D_
      link: function(scope, element, attr) {_x000D_
        // Parse the attribute to accomodate assignment to an object_x000D_
        var parseObj = attr.inputFocusFunction.split('.');_x000D_
        var attachTo = scope;_x000D_
        for (var i = 0; i < parseObj.length - 1; i++) {_x000D_
          attachTo = attachTo[parseObj[i]];_x000D_
        // assign it to a function that focuses on the decorated element_x000D_
        attachTo[parseObj[parseObj.length - 1]] = function() {_x000D_
  .controller('main', function() {});
<script src=""></script>_x000D_
<body ng-app="app" ng-controller="main as vm">_x000D_
  <input input-focus-function="vm.focusOnSaveInput" ng-model="saveName">_x000D_
  <button ng-click="vm.focusOnSaveInput()">Focus</button>_x000D_

Edited to provide more explanation about the reason for this approach and to extend the code snippet for controller-as use.

Access restriction: The type 'Application' is not API (restriction on required library rt.jar)

I have eclipse JRE 8.112 , not sure if that matters but what i did was this:

  1. Right clicked on my projects folder
  2. went down to properties and clicked
  3. clicked on the java build path folder
  4. once inside, I was in the order and export
  5. I checked the JRE System Library [jre1.8.0_112]
  6. then moved it up above the one other JRE system library there (not sure if this mattered)
  7. then pressed ok

This solved my problem.

Disable all dialog boxes in Excel while running VB script?

In order to get around the Enable Macro prompt I suggest

Application.AutomationSecurity = msoAutomationSecurityForceDisable

Be sure to return it to default when you are done

Application.AutomationSecurity = msoAutomationSecurityLow

A reminder that the .SaveAs function contains all optional arguments.I recommend removing CreatBackup:= False as it is not necessary.

The most interesting way I think is to create an object of the workbook and access the .SaveAs property that way. I have not tested it but you are never using Workbooks.Open rendering Application.AutomationSecurity inapplicable. Possibly saving resources and time as well.

That said I was able to execute the following without any notifications on Excel 2013 windows 10.

    Option Explicit

    Sub Convert()

    OptimizeVBA (True)  
    'function to set all the things you want to set, but hate keying in

    Application.AutomationSecurity = msoAutomationSecurityForceDisable  
    'this should stop those pesky enable prompts

    ChDir "F:\VBA Macros\Stack Overflow Questions\When changing type xlsm to 
    xlsx stop popup"

    Workbooks.Open ("Book1.xlsm")

    ActiveWorkbook.SaveAs Filename:= _
    "F:\VBA Macros\Stack Overflow Questions\When changing type xlsm to xlsx_ 
    stop popup\Book1.xlsx" _
    , FileFormat:=xlOpenXMLWorkbook


    Application.AutomationSecurity = msoAutomationSecurityLow 
    'make sure you set this up when done

    Kill ("F:\VBA Macros\Stack Overflow Questions\When changing type xlsm_ 
    to xlsx stop popup\Book1.xlsx") 'clean up

    OptimizeVBA (False)
    End Sub

    Function OptimizeVBA(ByRef Status As Boolean)

    If Status = True Then
        Application.ScreenUpdating = False
        Application.Calculation = xlCalculationManual
        Application.DisplayAlerts = False
        Application.EnableEvents = False
        Application.ScreenUpdating = True
        Application.Calculation = xlCalculationAutomatic
        Application.DisplayAlerts = True
        Application.EnableEvents = True
    End If

    End Function

What's the difference between abstraction and encapsulation?

Abstraction: In case of an hardware abstraction layer, you have simple interfaces to trigger the hardware (e.g. turn enginge left/right) without knowing the hardware details behind. So hiding the complexity of the system. It's a simplified view of the real world.

Encapsulation: Hiding of object internals. The object is an abstraction of the real world. But the details of this object (like data structures...) can be hidden via encapsulation.

Why is it that "No HTTP resource was found that matches the request URI" here?

Try this mate, you can chuck it in the body like so...

    public bool SampleCall([FromBody]JObject data)
        var firstName = data["firstName"].ToString();
        var lastName= data["lastName"].ToString();
        var email = data["email"].ToString();
        var obj= data["toLastName"].ToObject<SomeObject>();

        return _someService.DoYourBiz(firstName, lastName, email, obj);

Find child element in AngularJS directive

In your link function, do this:

// link function
function (scope, element, attrs) {
  var myEl = angular.element(element[0].querySelector('.list-scrollable'));

Also, in your link function, don't name your scope variable using a $. That is an angular convention that is specific to built in angular services, and is not something that you want to use for your own variables.

From inside of a Docker container, how do I connect to the localhost of the machine?

Solution for Windows 10

Docker Community Edition 17.06.0-ce-win18 2017-06-28 (stable)

You can use DNS name of the host, to resolve to the internal IP. (Warning some sources mentioned windows but it should be win)

I needed to do something similar, that is connect from my Docker container to my localhost, which was running the Azure Storage Emulator and CosmosDB Emulator.

The Azure Storage Emulator by default listens on, while you can change the IP its bound too, I was looking for a solution that would work with default settings.

This also works for connecting from my Docker container to SQL Server and IIS, both running locally on my host with default port settings.

AngularJS Error: $injector:unpr Unknown Provider

Your angular module needs to be initialized properly. The global object app needs to be defined and initialized correctly to inject the service.

Please see below sample code for reference:


var app = angular.module('SampleApp',['ngRoute']); //You can inject the dependencies within the square bracket    

app.config(['$routeProvider', '$locationProvider', function($routeProvider, $locationProvider) {
    .when('/', {


app.factory('getSettings', ['$http', '$q', function($http, $q) {
  return {
    //Code edited to create a function as when you require service it returns object by default so you can't return function directly. That's what understand...
    getSetting: function (type) { 
      var q = $q.defer();
      $http.get('models/settings.json').success(function (data) {
        q.resolve(function() {
          var settings = jQuery.parseJSON(data);
          return settings[type];
      return q.promise;

app.controller("globalControl", ['$scope','getSettings', function ($scope,getSettings) {
  //Modified the function call for updated service
  var loadSettings = getSettings.getSetting('global');
  loadSettings.then(function(val) {
    $scope.settings = val;

Sample HTML code should be like this:

<!DOCTYPE html>
    <head lang="en">
        <title>Sample Application</title>
    <body ng-app="SampleApp" ng-controller="globalControl">
            Your UI elements go here
        <script src="app.js"></script>

Please note that the controller is not binding to an HTML tag but to the body tag. Also, please try to include your custom scripts at end of the HTML page as this is a standard practice to follow for performance reasons.

I hope this will solve your basic injection issue.

Razor MVC Populating Javascript array with Model Array

This is possible, you just need to loop through the razor collection

<script type="text/javascript">

    var myArray = [];

    @foreach (var d in



Hope this helps

Enable/Disable Anchor Tags using AngularJS


The OP has made this comment on another answer:

We can have ngDisabled for buttons or input tags; by using CSS we can make the button to look like anchor tag but that doesn't help much! I was more keen on looking how it can be done using directive approach or angular way of doing it?

You can use a variable inside the scope of your controller to disable the links/buttons according to the last button/link that you've clicked on by using ng-click to set the variable at the correct value and ng-disabled to disable the button when needed according to the value in the variable.

I've updated your Plunker to give you an idea.

But basically, it's something like this:

       <button ng-click="create()" ng-disabled="state === 'edit'">CREATE</button><br/>
       <button ng-click="edit()" ng-disabled="state === 'create'">EDIT</button><br/>
       <button href="" ng-click="delete()" ng-disabled="state === 'create' || state === 'edit'">DELETE</button>

AngularJS Directive Restrict A vs E


  1. Using your own html element like <my-directive></my-directive> wont work on IE8 without workaround (
  2. Using your own html elements will make html validation fail.
  3. Directives with equal one parameter can done like this:

<div data-my-directive="ValueOfTheFirstParameter"></div>

Instead of this:

<my-directive my-param="ValueOfTheFirstParameter"></my-directive>

We dont use custom html elements, because if this 2 facts.

Every directive by third party framework can be written in two ways:



<div data-my-directive></div>

does the same.

WebService Client Generation Error with JDK8

Enabling Access to External Schema

You need to enable the IDE and the GlassFish Server to access external schema to parse the WSDL file of the web service. To enable access you need to modify the configuration files of the IDE and the GlassFish Server. For more details, see the FAQ How to enable parsing of WSDL with an external schema? Configuring the IDE

To generate a web service client in the IDE from a web service or WSDL file you need to modify the IDE configuration file (netbeans.conf) to add the following switch to netbeans_default_options.


For more about locating and modifying the netbeans.conf configuration file, see Netbeans Conf FAQ. Configuring the GlassFish Server

If you are deploying to the GlassFish Server you need to modify the configuration file of the GlassFish Server (domain.xml) to enable the server to access external schemas to parse the wsdl file and generate the test client. To enable access to external schemas, open the GlassFish configuration file (GLASSFISH_INSTALL/glassfish/domains/domain1/config/domain.xml) and add the following JVM option element (in bold). You will need to restart the server for the change to take effect.


How to use the 'replace' feature for custom AngularJS directives?

replace:true is Deprecated

From the Docs:

replace ([DEPRECATED!], will be removed in next major release - i.e. v2.0)

specify what the template should replace. Defaults to false.

  • true - the template will replace the directive's element.
  • false - the template will replace the contents of the directive's element.

-- AngularJS Comprehensive Directive API

From GitHub:

Caitp-- It's deprecated because there are known, very silly problems with replace: true, a number of which can't really be fixed in a reasonable fashion. If you're careful and avoid these problems, then more power to you, but for the benefit of new users, it's easier to just tell them "this will give you a headache, don't do it".

-- AngularJS Issue #7636


Note: replace: true is deprecated and not recommended to use, mainly due to the issues listed here. It has been completely removed in the new Angular.

Issues with replace: true

For more information, see

Android: Test Push Notification online (Google Cloud Messaging)

Postman is a good solution and so is php fiddle. However to avoid putting in the GCM URL and the header information every time, you can also use this nifty GCM Notification Test Tool

Angular.js directive dynamic templateURL

emanuel.directive('hymn', function() {
   return {
       restrict: 'E',
       link: function(scope, element, attrs) {
           // some ode
       templateUrl: function(elem,attrs) {
           return attrs.templateUrl || 'some/path/default.html'

So you can provide templateUrl via markup

<hymn template-url="contentUrl"><hymn>

Now you just take a care that property contentUrl populates with dynamically generated path.

In Angular, how to pass JSON object/array into directive?

What you need is properly a service:

.factory('DataLayer', ['$http',

    function($http) {

        var factory = {};
        var locations;

        factory.getLocations = function(success) {
            $http.get('locations/locations.json').success(function(data) {
                locations = data;

        return factory;

The locations would be cached in the service which worked as singleton model. This is the right way to fetch data.

Use this service DataLayer in your controller and directive is ok as following:

appControllers.controller('dummyCtrl', function ($scope, DataLayer) {
        $scope.locations = data;

.directive('map', function(DataLayer) {
    return {
        restrict: 'E',
        replace: true,
        template: '<div></div>',
        link: function(scope, element, attrs) {

            DataLayer.getLocations(function(data) {
                angular.forEach(data, function(location, key){
                    //do something

Access Form - Syntax error (missing operator) in query expression

I did quickly fix it by going into "Design View" of the main Table of same Form and putting underline (_) between any field names that had spaces. I am now able to use the built in filters without the annoying popup about syntax problems.

org.hibernate.QueryException: could not resolve property: filename

Hibernate queries are case sensitive with property names (because they end up relying on getter/setter methods on the @Entity).

Make sure you refer to the property as fileName in the Criteria query, not filename.

Specifically, Hibernate will call the getter method of the filename property when executing that Criteria query, so it will look for a method called getFilename(). But the property is called FileName and the getter getFileName().

So, change the projection like so:


AngularJS $http, CORS and http authentication

For making a CORS request one must add headers to the request along with the same he needs to check of mode_header is enabled in Apache.

For enabling headers in Ubuntu:

sudo a2enmod headers

For php server to accept request from different origin use:

Header set Access-Control-Allow-Origin *
Header set Access-Control-Allow-Methods "GET, POST, PUT, DELETE"
Header always set Access-Control-Allow-Headers "x-requested-with, Content-Type, origin, authorization, accept, client-security-token"

Can not run Java Applets in Internet Explorer 11 using JRE 7u51

We had the same problems with IE11 and new Java. Try to add your site to compatibility view. You can find here how to do it.

How to enable compatibility view in Internet Explorer 11

You can try now if it works or not. After that you can remove site from compatibility view and it should also run.

How do I use Spring Boot to serve static content located in Dropbox folder?

@Mark Schäfer

Never too late, but add a slash (/) after static:


So http://<host>/index.html is now reachable.

Disable password authentication for SSH

In file /etc/ssh/sshd_config

# Change to no to disable tunnelled clear text passwords
#PasswordAuthentication no

Uncomment the second line, and, if needed, change yes to no.

Then run

service ssh restart

javax.xml.bind.UnmarshalException: unexpected element. Expected elements are (none)

Alternatively if you want to persist in using the DocumentType class. Then you could just add the following annotation on top of your DocumentType class.


Note: the String value "document" refers to the name of the root tag of the xml message.

Boolean operators ( &&, -a, ||, -o ) in Bash

Rule of thumb: Use -a and -o inside square brackets, && and || outside.

It's important to understand the difference between shell syntax and the syntax of the [ command.

  • && and || are shell operators. They are used to combine the results of two commands. Because they are shell syntax, they have special syntactical significance and cannot be used as arguments to commands.

  • [ is not special syntax. It's actually a command with the name [, also known as test. Since [ is just a regular command, it uses -a and -o for its and and or operators. It can't use && and || because those are shell syntax that commands don't get to see.

But wait! Bash has a fancier test syntax in the form of [[ ]]. If you use double square brackets, you get access to things like regexes and wildcards. You can also use shell operators like &&, ||, <, and > freely inside the brackets because, unlike [, the double bracketed form is special shell syntax. Bash parses [[ itself so you can write things like [[ $foo == 5 && $bar == 6 ]].

Understanding ibeacon distancing

Distances to the source of iBeacon-formatted advertisement packets are estimated from the signal path attenuation calculated by comparing the measured received signal strength to the claimed transmit power which the transmitter is supposed to encode in the advertising data.

A path loss based scheme like this is only approximate and is subject to variation with things like antenna angles, intervening objects, and presumably a noisy RF environment. In comparison, systems really designed for distance measurement (GPS, Radar, etc) rely on precise measurements of propagation time, in same cases even examining the phase of the signal.

As Jiaru points out, 160 ft is probably beyond the intended range, but that doesn't necessarily mean that a packet will never get through, only that one shouldn't expect it to work at that distance.

How do I install PHP cURL on Linux Debian?

Type in console as root:

apt-get update && apt-get install php5-curl

or with sudo:

sudo apt-get update && sudo apt-get install php5-curl

Sorry I missread.

1st, check your DNS config and if you can ping any host at all,


If it does not work, check /etc/resolv.conf or /etc/network/resolv.conf, if not, change your apt-source to a different one.



You should not use Ubuntu sources on Debian and vice versa.

AngularJS directive does not update on scope variable changes

A simple solution is to make the scope variable object. Then access the content with {{ whatever-object.whatever-property }}. The variable is not updating because JavaScript pass Primitive type by value. Whereas Object are passed by reference which solves the problem.

Why does my JavaScript code receive a "No 'Access-Control-Allow-Origin' header is present on the requested resource" error, while Postman does not?

In the below investigation as API, I use instead of http://myApiUrl/login from your question, because this first one working.

I assume that your page is on http://my-site.local:8088.

The reason why you see different results is that Postman:

  • set header (your API)
  • NOT set header Origin

This is similar to browsers' way of sending requests when the site and API has the same domain (browsers also set the header item Referer=http://my-site.local:8088, however I don't see it in Postman). When Origin header is not set, usually servers allow such requests by default.

Enter image description here

This is the standard way how Postman sends requests. But a browser sends requests differently when your site and API have different domains, and then CORS occurs and the browser automatically:

  • sets header (yours as API)
  • sets header Origin=http://my-site.local:8088 (your site)

(The header Referer has the same value as Origin). And now in Chrome's Console & Networks tab you will see:

Enter image description here

Enter image description here

When you have Host != Origin this is CORS, and when the server detects such a request, it usually blocks it by default.

Origin=null is set when you open HTML content from a local directory, and it sends a request. The same situation is when you send a request inside an <iframe>, like in the below snippet (but here the Host header is not set at all) - in general, everywhere the HTML specification says opaque origin, you can translate that to Origin=null. More information about this you can find here.

fetch('', {method: 'POST'});
Look on chrome-console > network tab

If you do not use a simple CORS request, usually the browser automatically also sends an OPTIONS request before sending the main request - more information is here. The snippet below shows it:

fetch('', {_x000D_
  method: 'POST',_x000D_
  headers: { 'Content-Type': 'application/json'}_x000D_
Look in chrome-console -> network tab to 'api' request._x000D_
This is the OPTIONS request (the server does not allow sending a POST request)

You can change the configuration of your server to allow CORS requests.

Here is an example configuration which turns on CORS on nginx (nginx.conf file) - be very careful with setting always/"$http_origin" for nginx and "*" for Apache - this will unblock CORS from any domain.

location ~ ^/index\.php(/|$) {_x000D_
    add_header 'Access-Control-Allow-Origin' "$http_origin" always;_x000D_
    add_header 'Access-Control-Allow-Credentials' 'true' always;_x000D_
    if ($request_method = OPTIONS) {_x000D_
        add_header 'Access-Control-Allow-Origin' "$http_origin"; # DO NOT remove THIS LINES (doubled with outside 'if' above)_x000D_
        add_header 'Access-Control-Allow-Credentials' 'true';_x000D_
        add_header 'Access-Control-Max-Age' 1728000; # cache preflight value for 20 days_x000D_
        add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS';_x000D_
        add_header 'Access-Control-Allow-Headers' 'My-First-Header,My-Second-Header,Authorization,Content-Type,Accept,Origin';_x000D_
        add_header 'Content-Length' 0;_x000D_
        add_header 'Content-Type' 'text/plain charset=UTF-8';_x000D_
        return 204;_x000D_

Here is an example configuration which turns on CORS on Apache (.htaccess file)

# ------------------------------------------------------------------------------_x000D_
# | Cross-domain Ajax requests                                                 |_x000D_
# ------------------------------------------------------------------------------_x000D_
# Enable cross-origin Ajax requests._x000D_
# <IfModule mod_headers.c>_x000D_
#    Header set Access-Control-Allow-Origin "*"_x000D_
# </IfModule>_x000D_
# Header set Header set Access-Control-Allow-Origin "*"_x000D_
# Header always set Access-Control-Allow-Credentials "true"_x000D_
Access-Control-Allow-Origin ""_x000D_
Header always set Access-Control-Allow-Methods "POST, GET, OPTIONS, DELETE, PUT"_x000D_
Header always set Access-Control-Allow-Headers "My-First-Header,My-Second-Header,Authorization, content-type, csrf-token"

Angular JS: What is the need of the directive’s link function when we already had directive’s controller with scope?

After my initial struggle with the link and controller functions and reading quite a lot about them, I think now I have the answer.

First lets understand,

How do angular directives work in a nutshell:

  • We begin with a template (as a string or loaded to a string)

    var templateString = '<div my-directive>{{5 + 10}}</div>';

  • Now, this templateString is wrapped as an angular element

    var el = angular.element(templateString);

  • With el, now we compile it with $compile to get back the link function.

    var l = $compile(el)

    Here is what happens,

    • $compile walks through the whole template and collects all the directives that it recognizes.
    • All the directives that are discovered are compiled recursively and their link functions are collected.
    • Then, all the link functions are wrapped in a new link function and returned as l.
  • Finally, we provide scope function to this l (link) function which further executes the wrapped link functions with this scope and their corresponding elements.


  • This adds the template as a new node to the DOM and invokes controller which adds its watches to the scope which is shared with the template in DOM.

enter image description here

Comparing compile vs link vs controller :

  • Every directive is compiled only once and link function is retained for re-use. Therefore, if there's something applicable to all instances of a directive should be performed inside directive's compile function.

  • Now, after compilation we have link function which is executed while attaching the template to the DOM. So, therefore we perform everything that is specific to every instance of the directive. For eg: attaching events, mutating the template based on scope, etc.

  • Finally, the controller is meant to be available to be live and reactive while the directive works on the DOM (after getting attached). Therefore:

    (1) After setting up the view[V] (i.e. template) with link. $scope is our [M] and $controller is our [C] in M V C

    (2) Take advantage the 2-way binding with $scope by setting up watches.

    (3) $scope watches are expected to be added in the controller since this is what is watching the template during run-time.

    (4) Finally, controller is also used to be able to communicate among related directives. (Like myTabs example in

    (5) It's true that we could've done all this in the link function as well but its about separation of concerns.

Therefore, finally we have the following which fits all the pieces perfectly :

enter image description here

SOAP vs REST (differences)

REST(REpresentational State Transfer)
REpresentational State of an Object is Transferred is REST i.e. we don't send Object, we send state of Object. REST is an architectural style. It doesn’t define so many standards like SOAP. REST is for exposing Public APIs(i.e. Facebook API, Google Maps API) over the internet to handle CRUD operations on data. REST is focused on accessing named resources through a single consistent interface.

SOAP(Simple Object Access Protocol)
SOAP brings its own protocol and focuses on exposing pieces of application logic (not data) as services. SOAP exposes operations. SOAP is focused on accessing named operations, each operation implement some business logic. Though SOAP is commonly referred to as web services this is misnomer. SOAP has a very little if anything to do with the Web. REST provides true Web services based on URIs and HTTP.


  • Since REST uses standard HTTP it is much simpler in just about ever way.
  • REST is easier to implement, requires less bandwidth and resources.
  • REST permits many different data formats where as SOAP only permits XML.
  • REST allows better support for browser clients due to its support for JSON.
  • REST has better performance and scalability. REST reads can be cached, SOAP based reads cannot be cached.
  • If security is not a major concern and we have limited resources. Or we want to create an API that will be easily used by other developers publicly then we should go with REST.
  • If we need Stateless CRUD operations then go with REST.
  • REST is commonly used in social media, web chat, mobile services and Public APIs like Google Maps.
  • RESTful service return various MediaTypes for the same resource, depending on the request header parameter "Accept" as application/xml or application/json for POST and /user/1234.json or GET /user/1234.xml for GET.
  • REST services are meant to be called by the client-side application and not the end user directly.
  • ST in REST comes from State Transfer. You transfer the state around instead of having the server store it, this makes REST services scalable.


  • SOAP is not very easy to implement and requires more bandwidth and resources.
  • SOAP message request is processed slower as compared to REST and it does not use web caching mechanism.
  • WS-Security: While SOAP supports SSL (just like REST) it also supports WS-Security which adds some enterprise security features.
  • WS-AtomicTransaction: Need ACID Transactions over a service, you’re going to need SOAP.
  • WS-ReliableMessaging: If your application needs Asynchronous processing and a guaranteed level of reliability and security. Rest doesn’t have a standard messaging system and expects clients to deal with communication failures by retrying.
  • If the security is a major concern and the resources are not limited then we should use SOAP web services. Like if we are creating a web service for payment gateways, financial and telecommunication related work then we should go with SOAP as here high security is needed.

enter image description here


How to use BeanUtils.copyProperties?

As you can see in the below source code, BeanUtils.copyProperties internally uses reflection and there's additional internal cache lookup steps as well which is going to add cost wrt performance

 private static void copyProperties(Object source, Object target, @Nullable Class<?> editable,
                @Nullable String... ignoreProperties) throws BeansException {

            Assert.notNull(source, "Source must not be null");
            Assert.notNull(target, "Target must not be null");

            Class<?> actualEditable = target.getClass();
            if (editable != null) {
                if (!editable.isInstance(target)) {
                    throw new IllegalArgumentException("Target class [" + target.getClass().getName() +
                            "] not assignable to Editable class [" + editable.getName() + "]");
                actualEditable = editable;
            **PropertyDescriptor[] targetPds = getPropertyDescriptors(actualEditable);**
            List<String> ignoreList = (ignoreProperties != null ? Arrays.asList(ignoreProperties) : null);

            for (PropertyDescriptor targetPd : targetPds) {
                Method writeMethod = targetPd.getWriteMethod();
                if (writeMethod != null && (ignoreList == null || !ignoreList.contains(targetPd.getName()))) {
                    PropertyDescriptor sourcePd = getPropertyDescriptor(source.getClass(), targetPd.getName());
                    if (sourcePd != null) {
                        Method readMethod = sourcePd.getReadMethod();
                        if (readMethod != null &&
                                ClassUtils.isAssignable(writeMethod.getParameterTypes()[0], readMethod.getReturnType())) {
                            try {
                                if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {
                                Object value = readMethod.invoke(source);
                                if (!Modifier.isPublic(writeMethod.getDeclaringClass().getModifiers())) {
                                writeMethod.invoke(target, value);
                            catch (Throwable ex) {
                                throw new FatalBeanException(
                                        "Could not copy property '" + targetPd.getName() + "' from source to target", ex);

So it's better to use plain setters given the cost reflection

Apache: Restrict access to specific source IP inside virtual host

If you are using apache 2.2 inside your virtual host you should add following directive (mod_authz_host):

Order deny,allow
Deny from all
Allow from

You can even specify a subnet

Allow from 10.0.0

Apache 2.4 looks like a little different as configuration. Maybe better you specify which version of apache are you using.

How to force input to only allow Alpha Letters?

On newer browsers, you can use:

<input type="text" name="country_code" 
    pattern="[A-Za-z]" title="Three letter country code">

You can use regular expressions to restrict the input fields.

AngularJS resource promise

$q.when(scope.regions).then(function(result) {
var Regions = $resource('mocks/regions.json');
$scope.regions = Regions.query().$promise.then(function(response) {
    return response;

How to restrict user to type 10 digit numbers in input element?

The snippet below does the job as expected!

<input type="text" name="AUS" pattern="[0-9]{10}" title="You can enter only 10 digits..." />

//type="text" <!-- always -->
//name="AUS" <!-- for Australia -->
//pattern="[0-9]{10}" <!-- 10 digits from 0 to 9 -->
//title="You can enter only 10 digits..." <!-- Pops a warning when input mismatches -->

How to replace NA values in a table for selected columns

You can do:

x[, 1:2][[, 1:2])] <- 0

or better (IMHO), use the variable names:

x[c("a", "b")][[c("a", "b")])] <- 0

In both cases, 1:2 or c("a", "b") can be replaced by a pre-defined vector.

Is there a way to use SVG as content in a pseudo element :before or :after

.myDiv {
  display: flex;
  align-items: center;

.myDiv:before {
  display: inline-block;
  content: url(./dog.svg);
  margin-right: 15px;
  width: 10px;

Add directives from directive in AngularJS

You can actually handle all of this with just a simple template tag. See for an example. Note that I actually didn't need a compile or link property on the super-directive definition.

During the compilation process, Angular pulls in the template values before compiling, so you can attach any further directives there and Angular will take care of it for you.

If this is a super directive that needs to preserve the original internal content, you can use transclude : true and replace the inside with <ng-transclude></ng-transclude>

Hope that helps, let me know if anything is unclear


How do I get the offset().top value of an element without using jQuery?

use getBoundingClientRect if $el is the actual DOM object:

var top = $el.getBoundingClientRect().top;


Fiddle will show that this will get the same value that jquery's offset top will give you

Edit: as mentioned in comments this does not account for scrolled content, below is the code that jQuery uses (5/13/2015)

offset: function( options ) {

    var docElem, win, rect, doc,
        elem = this[ 0 ];

    if ( !elem ) {

    rect = elem.getBoundingClientRect();

    // Make sure element is not hidden (display: none) or disconnected
    if ( rect.width || rect.height || elem.getClientRects().length ) {
        doc = elem.ownerDocument;
        win = getWindow( doc );
        docElem = doc.documentElement;

        return {
            top: + win.pageYOffset - docElem.clientTop,
            left: rect.left + win.pageXOffset - docElem.clientLeft

Transfer data between iOS and Android via Bluetooth?

Maybe a bit delayed, but technologies have evolved since so there is certainly new info around which draws fresh light on the matter...

As iOS has yet to open up an API for WiFi Direct and Multipeer Connectivity is iOS only, I believe the best way to approach this is to use BLE, which is supported by both platforms (some better than others).

On iOS a device can act both as a BLE Central and BLE Peripheral at the same time, on Android the situation is more complex as not all devices support the BLE Peripheral state. Also the Android BLE stack is very unstable (to date).

If your use case is feature driven, I would suggest to look at Frameworks and Libraries that can achieve cross platform communication for you, without you needing to build it up from scratch.

For example: or google nearby

Disclaimer: I work for Uepaa, developing for Android and iOS.

How to use passive FTP mode in Windows command prompt?

According to this Egnyte article, Passive FTP is supported from Windows 8.1 onwards.

The Registry key:

"HKEY_CURRENT_USER\Software\Microsoft\FTP\Use PASV"

should be set with the value: yes

If you don't like poking around in the Registry, do the following:

  1. Press WinKey+R to open the Run dialog.
  2. Type inetcpl.cpl and press Enter. The Internet Options dialog will open.
  3. Click on the Advanced tab.
  4. Make your way down to the Browsing secction of the tree view, and ensure the Use Passive FTP item is set to on.
  5. Click on the OK button.

Every time you use ftp.exe, remember to pass the

quote pasv

command immediately after logging in to a remote host.

PS: Grant ftp.exe access to private networks if your Firewall complains.

AngularJS - pass function to directive

How about passing the controller function with bidirectional binding? Then you can use it in the directive exactly the same way as in a regular template (I stripped irrelevant parts for simplicity):

<div ng-controller="testCtrl">

   <!-- pass the function with no arguments -->
   <test color1="color1" update-fn="updateFn"></test>

   angular.module('dr', [])
   .controller("testCtrl", function($scope) {
      $scope.updateFn = function(msg) {
   .directive('test', function() {
      return {
         scope: {
            updateFn: '=' // '=' bidirectional binding
         template: "<button ng-click='updateFn(1337)'>Click</button>"

I landed at this question, because I tried the method above befire, but somehow it didn't work. Now it works perfectly.

How to send a correct authorization header for basic authentication

PHP - curl:

$username = 'myusername';
$password = 'mypassword';
curl_setopt($ch, CURLOPT_USERPWD, $username . ":" . $password);

PHP - POST in WordPress:

$username = 'myusername';
$password = 'mypassword';
wp_remote_post('https://...some...api...endpoint...', array(
  'headers' => array(
    'Authorization' => 'Basic ' . base64_encode("$username:$password")

Compiling dynamic HTML strings from database

In angular 1.2.10 the line scope.$watch(attrs.dynamic, function(html) { was returning an invalid character error because it was trying to watch the value of attrs.dynamic which was html text.

I fixed that by fetching the attribute from the scope property

 scope: { dynamic: '=dynamic'}, 

My example

  .directive('dynamic', function ($compile) {
    return {
      restrict: 'A',
      replace: true,
      scope: { dynamic: '=dynamic'},
      link: function postLink(scope, element, attrs) {
        scope.$watch( 'dynamic' , function(html){

jQuery ui datepicker with Angularjs

I modified the code and wrapped view update inside $apply().

link: function (scope, elem, attrs, ngModelCtrl){   
var updateModel = function(dateText){
    // call $apply to update the model
var options = {
    dateFormat: "dd/mm/yy",
     // handle jquery date change
    onSelect: function(dateText){
 // jqueryfy the element


working fiddle -

How to make cross domain request

Do a cross-domain AJAX call

Your web-service must support method injection in order to do JSONP.

Your code seems fine and it should work if your web services and your web application hosted in the same domain.

When you do a $.ajax with dataType: 'jsonp' meaning that jQuery is actually adding a new parameter to the query URL.

For instance, if your URL is then jQuery will add ?callback={some_random_dynamically_generated_method}.

This method is more kind of a proxy actually attached in window object. This is nothing specific but does look something like this:

window.some_random_dynamically_generated_method = function(actualJsonpData) {
    //here actually has reference to the success function mentioned with $.ajax
    //so it just calls the success method like this: 

Check the following for more information

Make cross-domain ajax JSONP request with jQuery

angularjs directive call function specified in attribute and pass an argument to it

This should work.

<div my-method='theMethodToBeCalled'></div>

app.directive("myMethod",function($parse) {
  scope: {theMethodToBeCalled: "="}
  link:function(scope,element,attrs) {
     $(element).on('theEvent',function( e, rowid ) {
        id = // some function called to determine id based on rowid

app.controller("myController",function($scope) {
   $scope.theMethodToBeCalled = function(id) { alert(id); };

HTML5 pattern for formatting input box to take date mm/dd/yyyy?

I use this website and this pattern do leap year validation as well.

<input type="text" pattern="(?:19|20)[0-9]{2}-(?:(?:0[1-9]|1[0-2])-(?:0[1-9]|1[0-9]|2[0-9])|(?:(?!02)(?:0[1-9]|1[0-2])-(?:30))|(?:(?:0[13578]|1[02])-31))" required />

Correct way to integrate jQuery plugins in AngularJS

i have alreay 2 situations where directives and services/factories didnt play well.

the scenario is that i have (had) a directive that has dependency injection of a service, and from the directive i ask the service to make an ajax call (with $http).

in the end, in both cases the ng-Repeat did not file at all, even when i gave the array an initial value.

i even tried to make a directive with a controller and an isolated-scope

only when i moved everything to a controller and it worked like magic.

example about this here Initialising jQuery plugin (RoyalSlider) in Angular JS

Change class on mouseover in directive

In general I fully agree with Jason's use of css selector, but in some cases you may not want to change the css, e.g. when using a 3rd party css-template, and rather prefer to add/remove a class on the element.

The following sample shows a simple way of adding/removing a class on ng-mouseenter/mouseleave:

<div ng-app>
    ng-class="{red: hover}"
    ng-init="hover = false"
    ng-mouseenter="hover = true"
    ng-mouseleave="hover = false">
      Test 1 2 3.

with some styling:

.red {
  background-color: red;

.italic {
  font-style: italic;
  color: black;

See running example here: jsfiddle sample

Styling on hovering is a view concern. Although the solution above sets a "hover" property in the current scope, the controller does not need to be concerned about this.

How to call a method defined in an AngularJS directive?

Just use scope.$parent to associate function called to directive function

angular.module('myApp', [])
.controller('MyCtrl',['$scope',function($scope) {

 function link(scope, el, attr){
   //use scope.$parent to associate the function called to directive function
   scope.$parent.myfunction = function directivefunction(parameter){
     //do something
return {
        link: link,
        restrict: 'E'   


<div ng-controller="MyCtrl">
    <button ng-click="myfunction(parameter)">call()</button>

Add an incremental number in a field in INSERT INTO SELECT query in SQL Server

You can use the row_number() function for this.

INSERT INTO PM_Ingrediants_Arrangements_Temp(AdminID, ArrangementID, IngrediantID, Sequence)
    SELECT @AdminID, @ArrangementID, PM_Ingrediants.ID,
            row_number() over (order by (select NULL))
    FROM PM_Ingrediants 
    WHERE PM_Ingrediants.ID IN (SELECT ID FROM GetIDsTableFromIDsList(@IngrediantsIDs)

If you want to start with the maximum already in the table then do:

INSERT INTO PM_Ingrediants_Arrangements_Temp(AdminID, ArrangementID, IngrediantID, Sequence)
    SELECT @AdminID, @ArrangementID, PM_Ingrediants.ID,
           coalesce(const.maxs, 0) + row_number() over (order by (select NULL))
    FROM PM_Ingrediants cross join
         (select max(sequence) as maxs from PM_Ingrediants_Arrangement_Temp) const
    WHERE PM_Ingrediants.ID IN (SELECT ID FROM GetIDsTableFromIDsList(@IngrediantsIDs)

Finally, you can just make the sequence column an auto-incrementing identity column. This saves the need to increment it each time:

create table PM_Ingrediants_Arrangement_Temp ( . . .
    sequence int identity(1, 1) -- and might consider making this a primary key too
    . . .

printf a variable in C

As Shafik already wrote you need to use the right format because scanf gets you a char. Don't hesitate to look here if u aren't sure about the usage:

Hint: It's faster/nicer to write x=x+1; the shorter way: x++;

Sorry for answering what's answered just wanted to give him the link - the site was really useful to me all the time dealing with C.

How to specify an alternate location for the .m2 folder or settings.xml permanently?

You need to add this line into your settings.xml (or uncomment if it's already there).


Also it's possible to run your commands with mvn clean install -gs C:\Users\me\.m2\settings.xml - this parameter will force maven to use different settings.xml then the default one (which is in $HOME/.m2/settings.xml)

Getting IP address of client

I use the following static helper method to retrieve the IP of a client:

public static String getClientIpAddr(HttpServletRequest request) {  
    String ip = request.getHeader("X-Forwarded-For");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("Proxy-Client-IP");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("WL-Proxy-Client-IP");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_X_FORWARDED_FOR");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_X_FORWARDED");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_X_CLUSTER_CLIENT_IP");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_CLIENT_IP");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_FORWARDED_FOR");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_FORWARDED");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("HTTP_VIA");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getHeader("REMOTE_ADDR");  
    if (ip == null || ip.length() == 0 || ip.equalsIgnoreCase("unknown")) {  
        ip = request.getRemoteAddr();  
    return ip;  

How do I pass multiple attributes into an Angular.js attribute directive?

You do it exactly the same way as you would with an element directive. You will have them in the attrs object, my sample has them two-way binding via the isolate scope but that's not required. If you're using an isolated scope you can access the attributes with scope.$eval(attrs.sample) or simply scope.sample, but they may not be defined at linking depending on your situation.

app.directive('sample', function () {
    return {
        restrict: 'A',
        scope: {
            'sample' : '=',
            'another' : '='
        link: function (scope, element, attrs) {
            scope.$watch('sample', function (newVal) {
                console.log('sample', newVal);
            scope.$watch('another', function (newVal) {
                console.log('another', newVal);

used as:

<input type="text" ng-model="name" placeholder="Enter a name here">
<input type="text" ng-model="something" placeholder="Enter something here">
<div sample="name" another="something"></div>

Codeigniter's `where` and `or_where`

You may group your library.available_until wheres area by grouping method of Codeigniter for without disable escaping where clauses.

    ->where('library.rating >=', $form['slider'])
    ->where('library.votes >=', '1000')
    ->where('library.language !=', 'German')
    ->group_start() //this will start grouping
    ->where('library.available_until >=', date("Y-m-d H:i:s"))
    ->or_where('library.available_until =', "00-00-00 00:00:00")
    ->group_end() //this will end grouping
    ->where('library.release_year >=', $year_start)
    ->where('library.release_year <=', $year_end)
    ->join('rating_repo', ' =')


AngularJS - Attribute directive input value change

To watch out the runtime changes in value of a custom directive, use $observe method of attrs object, instead of putting $watch inside a custom directive. Here is the documentation for the same ... $observe docs

error: package javax.servlet does not exist

I only put this code in my pom.xml and I executed the command maven install.


Why does the preflight OPTIONS request of an authenticated CORS request work in Chrome but not Firefox?

Why does it work in Chrome and not Firefox?

The W3 spec for CORS preflight requests clearly states that user credentials should be excluded. There is a bug in Chrome and WebKit where OPTIONS requests returning a status of 401 still send the subsequent request.

Firefox has a related bug filed that ends with a link to the W3 public webapps mailing list asking for the CORS spec to be changed to allow authentication headers to be sent on the OPTIONS request at the benefit of IIS users. Basically, they are waiting for those servers to be obsoleted.

How can I get the OPTIONS request to send and respond consistently?

Simply have the server (API in this example) respond to OPTIONS requests without requiring authentication.

Kinvey did a good job expanding on this while also linking to an issue of the Twitter API outlining the catch-22 problem of this exact scenario interestingly a couple weeks before any of the browser issues were filed.

How to require a controller in an angularjs directive

There is a good stackoverflow answer here by Mark Rajcok:

AngularJS directive controllers requiring parent directive controllers?

with a link to this very clear jsFiddle:

<div ng-controller="MyCtrl">
    <div screen>
        <div component>
            <div widget>
                <button ng-click="widgetIt()">Woo Hoo</button>


var myApp = angular.module('myApp',[])

.directive('screen', function() {
    return {
        scope: true,
        controller: function() {
            this.doSomethingScreeny = function() {

.directive('component', function() {
    return {
        scope: true,
        require: '^screen',
        controller: function($scope) {
            this.componentFunction = function() {
        link: function(scope, element, attrs, screenCtrl) {
            scope.screenCtrl = screenCtrl

.directive('widget', function() {
    return {
        scope: true,
        require: "^component",
        link: function(scope, element, attrs, componentCtrl) {
            scope.widgetIt = function() {

//myApp.directive('myDirective', function() {});
//myApp.factory('myService', function() {});

function MyCtrl($scope) {
    $ = 'Superhero';

Can I inject a service into a directive in AngularJS?

You can do injection on Directives, and it looks just like it does everywhere else.

app.directive('changeIt', ['myData', function(myData){
    return {
        restrict: 'C',
        link: function (scope, element, attrs) {

An Authentication object was not found in the SecurityContext - Spring 3.2.2

There is similar issue. I added listener as given here

It worked for me adding below lines to web.xml. Posting it very late, should help someone looking for answer.


AngularJS: ng-repeat list is not updated when a model element is spliced from the model array

There's an easy way to do that. Very easy. Since I noticed that

$scope.yourModel = [];

removes all $scope.yourModel array list you can do like this

function deleteAnObjectByKey(objects, key) {
    var clonedObjects = Object.assign({}, objects);

     for (var x in clonedObjects)
        if (clonedObjects.hasOwnProperty(x))
             if (clonedObjects[x].id == key)
                 delete clonedObjects[x];

    $scope.yourModel = clonedObjects;

The $scope.yourModel will be updated with the clonedObjects.

Hope that helps.

How to filter rows in pandas by regex

Use contains instead:

In [10]: df.b.str.contains('^f')
0    False
1     True
2     True
3    False
Name: b, dtype: bool

How to display length of filtered ng-repeat data

You can do it with 2 ways. In template and in Controller. In template you can set your filtered array to another variable, then use it like you want. Here is how to do it:

  <li data-ng-repeat="user in usersList = (users | gender:filterGender)" data-ng-bind=""></li>
<span>{{ usersList.length | number }}</span>

If you need examples, see the AngularJs filtered count examples/demos

How can I dynamically add a directive in AngularJS?

Josh David Miller is correct.

PCoelho, In case you're wondering what $compile does behind the scenes and how HTML output is generated from the directive, please take a look below

The $compile service compiles the fragment of HTML("< test text='n' >< / test >") that includes the directive("test" as an element) and produces a function. This function can then be executed with a scope to get the "HTML output from a directive".

var compileFunction = $compile("< test text='n' > < / test >");
var HtmlOutputFromDirective = compileFunction($scope);

More details with full code samples here:

Calling a function when ng-repeat has finished

Use $evalAsync if you want your callback (i.e., test()) to be executed after the DOM is constructed, but before the browser renders. This will prevent flicker -- ref.

if (scope.$last) {


If you really want to call your callback after rendering, use $timeout:

if (scope.$last) {
   $timeout(function() { 

I prefer $eval instead of an event. With an event, we need to know the name of the event and add code to our controller for that event. With $eval, there is less coupling between the controller and the directive.

"Thinking in AngularJS" if I have a jQuery background?

To describe the "paradigm shift", I think a short answer can suffice.

AngularJS changes the way you find elements

In jQuery, you typically use selectors to find elements, and then wire them up:
$('#id .class').click(doStuff);

In AngularJS, you use directives to mark the elements directly, to wire them up:
<a ng-click="doStuff()">

AngularJS doesn't need (or want) you to find elements using selectors - the primary difference between AngularJS's jqLite versus full-blown jQuery is that jqLite does not support selectors.

So when people say "don't include jQuery at all", it's mainly because they don't want you to use selectors; they want you to learn to use directives instead. Direct, not select!

jQuery find() method not working in AngularJS directive

You can do it like this:

 var myApp = angular.module('myApp', [])
  .controller('Ctrl', ['$scope', function($scope) {
     $ = 3432
 .directive('test', function () {
    return {
       link: function (scope, elm, attr) {
           var look = elm.children('#findme').addClass("addedclass");

<div ng-app="myApp" ng-controller="Ctrl">
   <div test>TEST Div
      <div id="findme">{{aaa}}</div>

How to create a directive with a dynamic template in AngularJS?

I have been in the same situation, my complete solution has been posted here

Basically I load a template in the directive in this way

var tpl = '' + 
    <div ng-if="maxLength" 
    </div>' +
    '<div ng-if="required" 

then according to the value of maxLength and required I can dynamically load one of the 2 templates, only one of them at a time is shown if necessary.

I heope it helps.

AngularJS: Insert HTML from a string

you can also use $sce.trustAsHtml('"<h1>" + str + "</h1>"'),if you want to know more detail, please refer to $sce

Array.Add vs +=

When using the $array.Add()-method, you're trying to add the element into the existing array. An array is a collection of fixed size, so you will receive an error because it can't be extended.

$array += $element creates a new array with the same elements as old one + the new item, and this new larger array replaces the old one in the $array-variable

You can use the += operator to add an element to an array. When you use it, Windows PowerShell actually creates a new array with the values of the original array and the added value. For example, to add an element with a value of 200 to the array in the $a variable, type:

    $a += 200

Source: about_Arrays

+= is an expensive operation, so when you need to add many items you should try to add them in as few operations as possible, ex:

$arr = 1..3    #Array
$arr += (4..5) #Combine with another array in a single write-operation


If that's not possible, consider using a more efficient collection like List or ArrayList (see the other answer).

How do I restrict an input to only accept numbers?

   <input type="text" name="profileChildCount" id="profileChildCount" ng-model="profile.ChildCount" numeric-only maxlength="1" />

you can use numeric-only attribute .

Spring Security redirect to previous page after successful login

Back to previous page after succesfull login, we can use following custom authentication manager as follows:

<!-- enable use-expressions -->
    <http auto-config="true" use-expressions="true">
        <!-- src** matches: src/bar.c src/baz.c src/test/bartest.c-->
        <intercept-url pattern="/problemSolution/home/**" access="hasRole('ROLE_ADMIN')"/>
        <intercept-url pattern="favicon.ico" access="permitAll"/>

        <logout logout-url="/problemSolution/logout"
        <!-- enable csrf protection -->

    <beans:bean id="authenticationSuccessHandler"
        <beans:property name="defaultTargetUrl" value="/problemSolution/home"/>

    <!-- Select users and user_roles from database -->
        <authentication-provider user-service-ref="customUserDetailsService">
            <password-encoder hash="plaintext">

CustomUserDetailsService class

public class CustomUserDetailsService implements UserDetailsService {

        private UserService userService;

        public UserDetails loadUserByUsername(String userName)
                        throws UsernameNotFoundException {
                com.codesenior.telif.local.model.User domainUser = userService.getUser(userName);

                boolean enabled = true;
                boolean accountNonExpired = true;
                boolean credentialsNonExpired = true;
                boolean accountNonLocked = true;

                return new User(

        public Collection<? extends GrantedAuthority> getAuthorities(List<UserRole> userRoleList) {
                return getGrantedAuthorities(getRoles(userRoleList));

        public List<String> getRoles(List<UserRole> userRoleList) {

                List<String> roles = new ArrayList<String>();

                for(UserRole userRole:userRoleList){
                return roles;

        public static List<GrantedAuthority> getGrantedAuthorities(List<String> roles) {
                List<GrantedAuthority> authorities = new ArrayList<GrantedAuthority>();

                for (String role : roles) {
                        authorities.add(new SimpleGrantedAuthority(role));
                return authorities;


User Class

import com.codesenior.telif.local.model.UserRole;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

public class CustomUserDetailsService implements UserDetailsService {

        private UserService userService;

        public UserDetails loadUserByUsername(String userName)
                        throws UsernameNotFoundException {
                com.codesenior.telif.local.model.User domainUser = userService.getUser(userName);

                boolean enabled = true;
                boolean accountNonExpired = true;
                boolean credentialsNonExpired = true;
                boolean accountNonLocked = true;

                return new User(

        public Collection<? extends GrantedAuthority> getAuthorities(List<UserRole> userRoleList) {
                return getGrantedAuthorities(getRoles(userRoleList));

        public List<String> getRoles(List<UserRole> userRoleList) {

                List<String> roles = new ArrayList<String>();

                for(UserRole userRole:userRoleList){
                return roles;

        public static List<GrantedAuthority> getGrantedAuthorities(List<String> roles) {
                List<GrantedAuthority> authorities = new ArrayList<GrantedAuthority>();

                for (String role : roles) {
                        authorities.add(new SimpleGrantedAuthority(role));
                return authorities;


UserRole Class

public class UserRole {
        private Integer userRoleId;

        private String role;

        @ManyToMany(fetch = FetchType.LAZY, mappedBy = "userRoleList")
        private List<User> userList;

        public Integer getUserRoleId() {
                return userRoleId;

        public void setUserRoleId(Integer userRoleId) {
                this.userRoleId= userRoleId;

        public String getRole() {
                return role;

        public void setRole(String role) {
                this.role= role;

        public String toString() {
                return String.valueOf(userRoleId);

        public List<User> getUserList() {
                return userList;

        public void setUserList(List<User> userList) {
                this.userList= userList;

AngularJS - Create a directive that uses ng-model

EDIT: This answer is old and likely out of date. Just a heads up so it doesn't lead folks astray. I no longer use Angular so I'm not in a good position to make improvements.

It's actually pretty good logic but you can simplify things a bit.


var app = angular.module('plunker', []);

app.controller('MainCtrl', function($scope) {
  $scope.model = { name: 'World' };
  $ = "Felipe";

app.directive('myDirective', function($compile) {
  return {
    restrict: 'AE', //attribute or element
    scope: {
      myDirectiveVar: '=',
     //bindAttr: '='
    template: '<div class="some">' +
      '<input ng-model="myDirectiveVar"></div>',
    replace: true,
    //require: 'ngModel',
    link: function($scope, elem, attr, ctrl) {
      //var textField = $('input', elem).attr('ng-model', 'myDirectiveVar');
      // $compile(textField)($scope.$parent);

Html with directive

<body ng-controller="MainCtrl">
  This scope value <input ng-model="name">
  <my-directive my-directive-var="name"></my-directive>


.some {
  border: 1px solid #cacaca;
  padding: 10px;

You can see it in action with this Plunker.

Here's what I see:

  • I understand why you want to use 'ng-model' but in your case it's not necessary. ng-model is to link existing html elements with a value in the scope. Since you're creating a directive yourself you're creating a 'new' html element, so you don't need ng-model.

EDIT As mentioned by Mark in his comment, there's no reason that you can't use ng-model, just to keep with convention.

  • By explicitly creating a scope in your directive (an 'isolated' scope), the directive's scope cannot access the 'name' variable on the parent scope (which is why, I think, you wanted to use ng-model).
  • I removed ngModel from your directive and replaced it with a custom name that you can change to whatever.
  • The thing that makes it all still work is that '=' sign in the scope. Checkout the docs docs under the 'scope' header.

In general, your directives should use the isolated scope (which you did correctly) and use the '=' type scope if you want a value in your directive to always map to a value in the parent scope.

How to implement history.back() in angular.js

Or you can simply use code :



<a class="back" ng-class="icons">
   <img src="../media/icons/right_circular.png" onClick="javascript:history.go(-1);" />

$watch'ing for data changes in an Angular directive

Because if you want to trigger your data with deep of it,you have to pass 3th argument true of your listener.By default it's false and it meens that you function will trigger,only when your variable will change not it's field.

Limit the height of a responsive image with css

I set the below 3 styles to my img tag

max-height: 500px;
height: 70%;
width: auto;

What it does that for desktop screen img doesn't grow beyond 500px but for small mobile screens, it will shrink to 70% of the outer container. Works like a charm.

It also works width property.

cvc-elt.1: Cannot find the declaration of element 'MyElement'

I had this error for my XXX element and it was because my XSD was wrongly formatted according to javax.xml.bind v2.2.11 . I think it's using an older XSD format but I didn't bother to confirm.

My initial wrong XSD was alike the following:

<xs:element name="Document" type="Document"/>
<xs:complexType name="Document">
        <xs:element name="XXX" type="XXX_TYPE"/>

The good XSD format for my migration to succeed was the following:

<xs:element name="Document">
            <xs:element ref="XXX"/>
<xs:element name="XXX" type="XXX_TYPE"/>

And so on for every similar XSD nodes.

Scroll / Jump to id without jQuery

Add the function:

function scrollToForm() {
  document.querySelector('#form').scrollIntoView({behavior: 'smooth'});

Trigger the function:

<a href="javascript: scrollToForm();">Jump to form</a>

Reading RFID with Android phones

I recently worked on a project to read the RFID tags. The project used the Devices from manufacturers like Zebra (we were using RFD8500 ) & TSL.

More devices are from Motorola & other vendors as well!

We have to use the native SDK api's provided by the manufacturer, how it works is by pairing the device by the Bluetooth of the phones and so the data transfer between both devices take place! The programming is based on subscribe pattern where the scan should be read by the device trigger(hardware trigger) or soft trigger (from the application).

The Tag read gives us the tagId & the RSSI which is the distance factor from the RFID tags!

This is the sample app:

We get all the device paired to our Android/iOS phones :

get device list




Reference - What does this error mean in PHP?

Notice: Uninitialized string offset: *

As the name indicates, such type of error occurs, when you are most likely trying to iterate over or find a value from an array with a non-existing key.

Consider you, are trying to show every letter from $string

$string = 'ABCD'; 
for ($i=0, $len = strlen($string); $i <= $len; $i++){
    echo "$string[$i] \n"; 

The above example will generate (online demo):

Notice: Uninitialized string offset: 4 in XXX on line X

And, as soon as the script finishes echoing D you'll get the error, because inside the for() loop, you have told PHP to show you the from first to fifth string character from 'ABCD' Which, exists, but since the loop starts to count from 0 and echoes D by the time it reaches to 4, it will throw an offset error.

Similar Errors:

How to Increase Import Size Limit in phpMyAdmin

Could you also increase post_max_size and see if it helps?

Uploading a file through an HTML form makes the upload treated like any other form element content, that's why increasing post_max_size should be required too.

Update : the final solution involved the command-line:

To export only 1 table you would do

mysqldump -u user_name -p your_password your_database_name your_table_name > dump_file.sql

and to import :

mysql -u your_user -p your_database < dump_file.sql 

'drop table your_tabe_name;' can also be added at the top of the import script if it's not already there, to ensure the table gets deleted before the script creates and fill it

How do I find files with a path length greater than 260 characters in Windows?

TLPD ("too long path directory") is the program that saved me. Very easy to use:

Can you autoplay HTML5 videos on the iPad?

In this Safari HTML5 reference, you can read

To prevent unsolicited downloads over cellular networks at the user’s expense, embedded media cannot be played automatically in Safari on iOS—the user always initiates playback. A controller is automatically supplied on iPhone or iPod touch once playback in initiated, but for iPad you must either set the controls attribute or provide a controller using JavaScript.

Convert double to BigDecimal and set BigDecimal Precision

It prints 47.48000 if you use another MathContext:

BigDecimal b = new BigDecimal(d, MathContext.DECIMAL64);

Just pick the context you need.

How can I stop the browser back button using JavaScript?

Try it with ease:

history.pushState(null, null, document.title);
window.addEventListener('popstate', function () {
    history.pushState(null, null, document.title);

MySQL 1062 - Duplicate entry '0' for key 'PRIMARY'

Run the following query in the mysql console:

SHOW CREATE TABLE momento_distribution

Check for the line that looks something like

CONSTRAINT `momento_distribution_FK_1` FOREIGN KEY (`momento_id`) REFERENCES `momento` (`id`)

It may be different, I just put a guess as to what it could be. If you have a foreign key on both 'momento_id' & 'momento_idmember', you will get two foreign key names. The next step is to delete the foreign keys. Run the following queries:

ALTER TABLE momento_distribution DROP FOREIGN KEY momento_distribution_FK_1
ALTER TABLE momento_distribution DROP FOREIGN KEY momento_distribution_FK_2

Be sure to change the foreign key name to what you got from the CREATE TABLE query. Now you don't have any foreign keys so you can easily remove the primary key. Try the following:

ALTER TABLE  `momento_distribution` DROP PRIMARY KEY

Add the required column as follows:


This query also adds numbers so you won't need to depend on @rowid. Now you need to add the foreign key back to the earlier columns. For that, first make these indexes:

ALTER TABLE  `momento_distribution` ADD INDEX (  `momento_id` )
ALTER TABLE  `momento_distribution` ADD INDEX (  `momento_idmember` )

Now add the foreign keys. Change the Reference Table/column as you need:

ALTER TABLE  `momento_distribution` ADD FOREIGN KEY ( `momento_id`) REFERENCES  `momento` (`id`) ON DELETE RESTRICT ON UPDATE RESTRICT 
ALTER TABLE  `momento_distribution` ADD FOREIGN KEY ( `momento_idmember`) REFERENCES  `member` (`id`) ON DELETE RESTRICT ON UPDATE RESTRICT 

Hope that helps. If you get any errors, please edit the question with the structure of the reference tables & the error code(s) that you are getting.

How to make input type= file Should accept only pdf and xls

You could do so by using the attribute accept and adding allowed mime-types to it. But not all browsers do respect that attribute and it could easily be removed via some code inspector. So in either case you need to check the file type on the server side (your second question).


<input type="file" name="upload" accept="application/pdf,application/" />

To your third question "And when I click the files (PDF/XLS) on webpage it automatically should open.":

You can't achieve that. How a PDF or XLS is opened on the client machine is set by the user.

Global variables in AngularJS

If you just want to store a value, according to the Angular documentation on Providers, you should use the Value recipe:

var myApp = angular.module('myApp', []);
myApp.value('clientId', 'a12345654321x');

Then use it in a controller like this:

myApp.controller('DemoController', ['clientId', function DemoController(clientId) {
    this.clientId = clientId;

The same thing can be achieved using a Provider, Factory, or Service since they are "just syntactic sugar on top of a provider recipe" but using Value will achieve what you want with minimal syntax.

The other option is to use $rootScope, but it's not really an option because you shouldn't use it for the same reasons you shouldn't use global variables in other languages. It's advised to be used sparingly.

Since all scopes inherit from $rootScope, if you have a variable $ and someone forgets that data is already defined and creates $ in a local scope you will run into problems.

If you want to modify this value and have it persist across all your controllers, use an object and modify the properties keeping in mind Javascript is pass by "copy of a reference":

myApp.value('clientId', { value: 'a12345654321x' });
myApp.controller('DemoController', ['clientId', function DemoController(clientId) {
    this.clientId = clientId;
    this.change = function(value) {
        clientId.value = 'something else';

JSFiddle example

How to restrict the selectable date ranges in Bootstrap Datepicker?

i am using v3.1.3 and i had to use data('DateTimePicker') like this

var fromE = $( "#" + fromInput );
var toE = $( "#" + toInput );

$('.form-datepicker').on('change', function(e){
   var isTo = $(this).attr('name') === 'to';

   $( "#" + ( isTo ? fromInput : toInput  ) )
      .data('DateTimePicker')[ isTo ? 'setMaxDate' : 'setMinDate' ](moment($(this).val(), 'DD/MM/YYYY'))

Accessing attributes from an AngularJS directive

See section Attributes from documentation on directives.

observing interpolated attributes: Use $observe to observe the value changes of attributes that contain interpolation (e.g. src="{{bar}}"). Not only is this very efficient but it's also the only way to easily get the actual value because during the linking phase the interpolation hasn't been evaluated yet and so the value is at this time set to undefined.

How do you handle a "cannot instantiate abstract class" error in C++?

Provide implementation for any pure virtual functions that the class has.

Strict Standards: Only variables should be assigned by reference PHP 5.4

You should remove the & (ampersand) symbol, so that line 4 will look like this:

$conn = ADONewConnection($config['db_type']);

This is because ADONewConnection already returns an object by reference. As per documentation, assigning the result of a reference to object by reference results in an E_DEPRECATED message as of PHP 5.3.0

Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '='

Answer is adding to @Sebas' answer - setting the collation of my local environment. Do not try this on production.

ALTER DATABASE databasename CHARACTER SET utf8 COLLATE utf8_unicode_ci;

ALTER TABLE tablename CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;

Source of this solution

How to use HTTP_X_FORWARDED_FOR properly?

You can use this function to get proper client IP:

public function getClientIP(){       
     if (array_key_exists('HTTP_X_FORWARDED_FOR', $_SERVER)){
            return  $_SERVER["HTTP_X_FORWARDED_FOR"];  
     }else if (array_key_exists('REMOTE_ADDR', $_SERVER)) { 
            return $_SERVER["REMOTE_ADDR"]; 
     }else if (array_key_exists('HTTP_CLIENT_IP', $_SERVER)) {
            return $_SERVER["HTTP_CLIENT_IP"]; 

     return '';

How to get the caller class in Java

I know this is an old question but I believed the asker wanted the class, not the class name. I wrote a little method that will get the actual class. It is sort of cheaty and may not always work, but sometimes when you need the actual class, you will have to use this method...

     * Get the caller class.
     * @param level The level of the caller class.
     *              For example: If you are calling this class inside a method and you want to get the caller class of that method,
     *                           you would use level 2. If you want the caller of that class, you would use level 3.
     *              Usually level 2 is the one you want.
     * @return The caller class.
     * @throws ClassNotFoundException We failed to find the caller class.
    public static Class getCallerClass(int level) throws ClassNotFoundException {
        StackTraceElement[] stElements = Thread.currentThread().getStackTrace();
        String rawFQN = stElements[level+1].toString().split("\\(")[0];
        return Class.forName(rawFQN.substring(0, rawFQN.lastIndexOf('.')));

Dataset - Vehicle make/model/year (free)

Apparently there is not much out there. And a lot of doubt that someone would be willing to provide such a repository. So I solved the problem myself, and am sharing my dataset with anyone else who finds themselves facing the same problem.

List of IP Space used by Facebook

# Bloqueio facebook
for ip in `whois -h '!gAS32934' | grep /`
  iptables -A FORWARD -p all -d $ip -j REJECT

Restricting JTextField input to Integers

When you type integer numbers to JtextField1 after key release it will go to inside try , for any other character it will throw NumberFormatException. If you set empty string to jTextField1 inside the catch so the user cannot type any other keys except positive numbers because JTextField1 will be cleared for each bad attempt.

int x;
JTextField jTextField1;

 //Gui Code Here

private void jTextField1KeyReleased(java.awt.event.KeyEvent evt) {                                        
    try {
        x = Integer.parseInt(jTextField1.getText());
    } catch (NumberFormatException nfe) {

restrict edittext to single line

Add this line to your edittext


Error message "Forbidden You don't have permission to access / on this server"

I understand this issue is resolved but I happened to solve this same problem on my own.

The cause of

Forbidden You don't have permission to access / on this server

is actually the default configuration for an apache directory in httpd.conf.

# Each directory to which Apache has access can be configured with respect
# to which services and features are allowed and/or disabled in that
# directory (and its subdirectories). 
# First, we configure the "default" to be a very restrictive set of 
# features.  
<Directory "/">
    Options FollowSymLinks
    AllowOverride None
    Order deny,allow
    Deny from all          # the cause of permission denied

Simply changing Deny from all to Allow from all should solve the permission problem.

Alternatively, a better approach would be to specify individual directory permissions on virtualhost configuration.

<VirtualHost *:80>

    # Set access permission
    <Directory "/path/to/docroot">
        Allow from all


As of Apache-2.4, however, access control is done using the new module mod_authz_host (Upgrading to 2.4 from 2.2). Consequently, the new Require directive should be used.

<VirtualHost *:80>

    # Set access permission
    <Directory "/path/to/docroot">
        Require all granted


Multi-Column Join in Hibernate/JPA Annotations

If this doesn't work I'm out of ideas. This way you get the 4 columns in both tables (as Bar owns them and Foo uses them to reference Bar) and the generated IDs in both entities. The set of 4 columns has to be unique in Bar so the many-to-one relation doesn't become a many-to-many.

public class AnEmbeddedObject
    @Column(name = "column_1")
    private Long column1;
    @Column(name = "column_2")
    private Long column2;
    @Column(name = "column_3")
    private Long column3;
    @Column(name = "column_4")
    private Long column4;

public class Foo
    @Column(name = "id")
    @GeneratedValue(generator = "seqGen")
    @SequenceGenerator(name = "seqGen", sequenceName = "FOO_ID_SEQ", allocationSize = 1)
    private Long id;
    @ManyToOne(fetch = FetchType.LAZY)
        @JoinColumn(name = "column_1", referencedColumnName = "column_1"),
        @JoinColumn(name = "column_2", referencedColumnName = "column_2"),
        @JoinColumn(name = "column_3", referencedColumnName = "column_3"),
        @JoinColumn(name = "column_4", referencedColumnName = "column_4")
    private Bar bar;

@Table(uniqueConstraints = @UniqueConstraint(columnNames = {
public class Bar
    @Column(name = "id")
    @GeneratedValue(generator = "seqGen")
    @SequenceGenerator(name = "seqGen", sequenceName = "BAR_ID_SEQ", allocationSize = 1)
    private Long id;
    private AnEmbeddedObject anEmbeddedObject;

Customizing the template within a Directive

angular.module('formComponents', [])
  .directive('formInput', function() {
    return {
        restrict: 'E',
        compile: function(element, attrs) {
            var type = attrs.type || 'text';
            var required = attrs.hasOwnProperty('required') ? "required='required'" : "";
            var htmlText = '<div class="control-group">' +
                '<label class="control-label" for="' + attrs.formId + '">' + attrs.label + '</label>' +
                    '<div class="controls">' +
                    '<input type="' + type + '" class="input-xlarge" id="' + attrs.formId + '" name="' + attrs.formId + '" ' + required + '>' +
                    '</div>' +

Using ChildActionOnly in MVC

You would use it if you are using RenderAction in any of your views, usually to render a partial view.

The reason for marking it with [ChildActionOnly] is that you need the controller method to be public so you can call it with RenderAction but you don't want someone to be able to navigate to a URL (e.g. /Controller/SomeChildAction) and see the results of that action directly.

X-Frame-Options Allow-From multiple domains

X-Frame-Options is deprecated. From MDN:

This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Do not use it in old or new projects. Pages or Web apps using it may break at any time.

The modern alternative is the Content-Security-Policy header, which along many other policies can white-list what URLs are allowed to host your page in a frame, using the frame-ancestors directive.
frame-ancestors supports multiple domains and even wildcards, for example:

Content-Security-Policy: frame-ancestors 'self' * ;

Unfortunately, for now, Internet Explorer does not fully support Content-Security-Policy.

UPDATE: MDN has removed their deprecation comment. Here's a similar comment from W3C's Content Security Policy Level

The frame-ancestors directive obsoletes the X-Frame-Options header. If a resource has both policies, the frame-ancestors policy SHOULD be enforced and the X-Frame-Options policy SHOULD be ignored.

Allow only numbers and dot in script

function isNumber(evt) {
    evt = (evt) ? evt : window.event;
    var charCode = (evt.which) ? evt.which : evt.keyCode;
    if (charCode > 31 && (charCode < 46 || charCode > 57)) {
        return false;
    return true;

you should use this function and write the properties of this element ;

HTML Code:

<input id="deneme" data-mini="true" onKeyPress="return isNumber(event)" type="text"/>`

Why is my locally-created script not allowed to run under the RemoteSigned execution policy?

Run below 2 commands in PowerShell window

  1. Set-ExecutionPolicy unrestricted

  2. Unblock-File -Path D:\PowerShell\Script.ps1

html select only one checkbox in a group

And without jQuery, for a checkbox structure like this:

<input type="checkbox" id="mytrackers_1" name="blubb_1" value="">--- Bitte ausw&#228;hlen ---
<input type="checkbox" id="mytrackers_2" name="blubb_2" value="7">Testtracker
<input type="checkbox" id="mytrackers_3" name="blubb_3" value="3">Kundenanfrage
<input type="checkbox" id="mytrackers_4" name="blubb_4" value="2">Anpassung
<input type="checkbox" id="mytrackers_5" name="blubb_5" value="1" checked="checked" >Fehler
<input type="checkbox" id="mytrackers_6" name="blubb_6" value="4">Bedienung
<input type="checkbox" id="mytrackers_7" name="blubb_7" value="5">Internes
<input type="checkbox" id="mytrackers_8" name="blubb_8" value="6">&#196;nderungswunsch

you would do it like this:

    /// attach an event handler, now or in the future, 
    /// for all elements which match childselector,
    /// within the child tree of the element maching parentSelector.
    function subscribeEvent(parentSelector, eventName, childSelector, eventCallback) {
        if (parentSelector == null)
            throw new ReferenceError("Parameter parentSelector is NULL");
        if (childSelector == null)
            throw new ReferenceError("Parameter childSelector is NULL");
        // nodeToObserve: the node that will be observed for mutations
        var nodeToObserve = parentSelector;
        if (typeof (parentSelector) === 'string')
            nodeToObserve = document.querySelector(parentSelector);
        var eligibleChildren = nodeToObserve.querySelectorAll(childSelector);
        for (var i = 0; i < eligibleChildren.length; ++i) {
            eligibleChildren[i].addEventListener(eventName, eventCallback, false);
        } // Next i 
        function allDescendants(node) {
            if (node == null)
            for (var i = 0; i < node.childNodes.length; i++) {
                var child = node.childNodes[i];
            } // Next i 
            // IE 11 Polyfill 
            if (!Element.prototype.matches)
                Element.prototype.matches = Element.prototype.msMatchesSelector;
            if (node.matches) {
                if (node.matches(childSelector)) {
                    // console.log("match");
                    node.addEventListener(eventName, eventCallback, false);
                } // End if ((<Element>node).matches(childSelector))
                // else console.log("no match");
            } // End if ((<Element>node).matches) 
            // else console.log("no matchfunction");
        } // End Function allDescendants 
        // Callback function to execute when mutations are observed
        var callback = function (mutationsList, observer) {
            for (var _i = 0, mutationsList_1 = mutationsList; _i < mutationsList_1.length; _i++) {
                var mutation = mutationsList_1[_i];
                // console.log("mutation.type", mutation.type);
                // console.log("mutation", mutation);
                if (mutation.type == 'childList') {
                    for (var i = 0; i < mutation.addedNodes.length; ++i) {
                        var thisNode = mutation.addedNodes[i];
                    } // Next i 
                } // End if (mutation.type == 'childList') 
                // else if (mutation.type == 'attributes') { console.log('The ' + mutation.attributeName + ' attribute was modified.');
            } // Next mutation 
        }; // End Function callback 
        // Options for the observer (which mutations to observe)
        var config = { attributes: false, childList: true, subtree: true };
        // Create an observer instance linked to the callback function
        var observer = new MutationObserver(callback);
        // Start observing the target node for configured mutations
        observer.observe(nodeToObserve, config);
    } // End Function subscribeEvent 

    function radioCheckbox_onClick() 
        // console.log("click", this);
        let box = this;
        if (box.checked) 
            let name = box.getAttribute("name");
            let pos = name.lastIndexOf("_");
            if (pos !== -1) name = name.substr(0, pos);

            let group = 'input[type="checkbox"][name^="' + name + '"]';
            // console.log(group);
            let eles = document.querySelectorAll(group);
            // console.log(eles);
            for (let j = 0; j < eles.length; ++j) 
                eles[j].checked = false;
            box.checked = true;
            box.checked = false;

    function radioCheckbox()
        // on instead of document...
        let elements = document.querySelectorAll('input[type="checkbox"]')

        for (let i = 0; i < elements.length; ++i)
            // console.log(elements[i]);
            elements[i].addEventListener("click", radioCheckbox_onClick, false);

        } // Next i 

    } // End Function radioCheckbox 

    function onDomReady()
        console.log("dom ready");
        subscribeEvent(document, "click", 

        // radioCheckbox();

    if (document.addEventListener) document.addEventListener("DOMContentLoaded", onDomReady, false);
    else if (document.attachEvent) document.attachEvent("onreadystatechange", onDomReady);
    else window.onload = onDomReady;

    function onPageLoaded() {
        console.log("page loaded");

    if (window.addEventListener) window.addEventListener("load", onPageLoaded, false);
    else if (window.attachEvent) window.attachEvent("onload", onPageLoaded);
    else window.onload = onPageLoaded;

Access restriction: Is not accessible due to restriction on required library ..\jre\lib\rt.jar

Go to Buildpath

Remove Existing JRE and add new JRE library which contain Jdk1.6 and finish Now clean all project and build again

I think this way you can resolved your error

How to draw border on just one side of a linear layout?

it is also possible to implement what you want using a single layer

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="" >

        <shape android:shape="rectangle" >
            <solid android:color="@color/color_of_the_background" />

                android:color="@color/color_of_the_border" />


this way only left border is visible but you can achieve any combination you want by playing with bottom, left, right and top attributes of the item element

Bloomberg Open API

This API has been available for a long time and enables to get access to market data (including live) if you are running a Bloomberg Terminal or have access to a Bloomberg Server, which is chargeable.

The only difference is that the API (not its code) has been open sourced, so it can now be used as a dependency in an open source project for example, without any copyrights issues, which was not the case before.

How to filter input type="file" dialog by specific file type?

You can use the accept attribute along with the . It doesn't work in IE and Safari.

Depending on your project scale and extensibility, you could use Struts. Struts offers two ways to limit the uploaded file type, declaratively and programmatically.

For more information:

XML Schema How to Restrict Attribute by Enumeration

you need to create a type and make the attribute of that type:

<xs:simpleType name="curr">
  <xs:restriction base="xs:string">
    <xs:enumeration value="pounds" />
    <xs:enumeration value="euros" />
    <xs:enumeration value="dollars" />


    <xs:attribute name="currency" type="curr"/>

Number input type that takes only integers?

The integer input would mean that it can only take positive numbers, 0 and negative numbers too. This is how I have been able to achieve this using Javascript keypress.

<input type="number" (keypress)="keypress($event, $" >

keypress(evt, value){
    if (evt.charCode >= 48 && evt.charCode <= 57 || (value=="" && evt.charCode == 45))       
      return true;
    return false;

The given code won't allow user to enter alphabets nor decimal on runtime, just positive and negative integer values.

Hibernate Criteria Join with 3 Tables

The fetch mode only says that the association must be fetched. If you want to add restrictions on an associated entity, you must create an alias, or a subcriteria. I generally prefer using aliases, but YMMV:

Criteria c = session.createCriteria(Dokument.class, "dokument");
c.createAlias("dokument.role", "role"); // inner join by default
c.createAlias("", "contact");
c.add(Restrictions.eq("contact.lastName", "Test"));
return c.list();

This is of course well explained in the Hibernate reference manual, and the javadoc for Criteria even has examples. Read the documentation: it has plenty of useful information.

Limit number of characters allowed in form input text field

<input type="text" name="MobileNumber" id="MobileNumber" maxlength="10" onkeypress="checkNumber(event);"  placeholder="MobileNumber">

function checkNumber(key) {
  var inputNumber = document.querySelector("#MobileNumber").value;
  if(key.key >= 0 && key.key <= 9) {
    inputNumber += key.key;
  else {

Why is JsonRequestBehavior needed?

You do not need it.

If your action has the HttpPost attribute, then you do not need to bother with setting the JsonRequestBehavior and use the overload without it. There is an overload for each method without the JsonRequestBehavior enum. Here they are:

Without JsonRequestBehavior

protected internal JsonResult Json(object data);
protected internal JsonResult Json(object data, string contentType);
protected internal virtual JsonResult Json(object data, string contentType, Encoding contentEncoding);

With JsonRequestBehavior

protected internal JsonResult Json(object data, JsonRequestBehavior behavior);
protected internal JsonResult Json(object data, string contentType, 
                                   JsonRequestBehavior behavior);
protected internal virtual JsonResult Json(object data, string contentType, 
    Encoding contentEncoding, JsonRequestBehavior behavior);

How can I limit possible inputs in a HTML5 "number" element?

I know there's an answer already, but if you want your input to behave exactly like the maxlength attribute or as close as you can, use the following code:

(function($) {
 methods = {
     * addMax will take the applied element and add a javascript behavior
     * that will set the max length
    addMax: function() {
        // set variables
            maxlAttr = $(this).attr("maxlength"),
            maxAttR = $(this).attr("max"),
            x = 0,
            max = "";

        // If the element has maxlength apply the code.
        if (typeof maxlAttr !== typeof undefined && maxlAttr !== false) {

            // create a max equivelant
            if (typeof maxlAttr !== typeof undefined && maxlAttr !== false){
                while (x < maxlAttr) {
                    max += "9";
              maxAttR = max;

            // Permissible Keys that can be used while the input has reached maxlength
            var keys = [
                8, // backspace
                9, // tab
                13, // enter
                46, // delete
                37, 39, 38, 40 // arrow keys<^>v

            // Apply changes to element
                .attr("max", maxAttR) //add existing max or new max
                .keydown(function(event) {
                    // restrict key press on length reached unless key being used is in keys array or there is highlighted text
                    if ($(this).val().length == maxlAttr && $.inArray(event.which, keys) == -1 && methods.isTextSelected() == false) return false;
     * isTextSelected returns true if there is a selection on the page. 
     * This is so that if the user selects text and then presses a number
     * it will behave as normal by replacing the selection with the value
     * of the key pressed.
    isTextSelected: function() {
       // set text variable
        text = "";
        if (window.getSelection) {
            text = window.getSelection().toString();
        } else if (document.selection && document.selection.type != "Control") {
            text = document.selection.createRange().text;
        return (text.length > 0);

$.maxlengthNumber = function(){
     // Get all number inputs that have maxlength$("input[type=number]"));


// Apply it:

Jenkins restrict view of jobs per user

You can install "Extended Read Permission" plug-in. Then in either "Global Settings" or in individual job configuration, you can give the user "Extended Read" permission.

iOS Launching Settings -> Restrictions URL Scheme

Here is something else I found:

  1. After I have the "prefs" URL Scheme defined, "prefs:root=Safari&path=ContentBlockers" is working on Simulator (iOS 9.1 English), but not working on Simulator (Simplified Chinese). It just jump to Safari, but not Content Blockers. If your app is international, be careful.
    Update: Don't know why, now I can't jump into ContentBlockers anymore, the same code, the same version, doesn't work now. :(

  2. On real devcies (mine is iPhone 6S & iPad mini 2), "Safari" should be "SAFARI", "Safari" not working on real device, "SAFARI" now working on simulator:

    #if arch(i386) || arch(x86_64)
        // Simulator
        let url = NSURL(string: "prefs:root=Safari")!
        // Device
        let url = NSURL(string: "prefs:root=SAFARI")!
    if UIApplication.sharedApplication().canOpenURL(url) {
  3. So far, did not find any differences between iPhone and iPad.

Mercurial: how to amend the last commit?

I'm tuning into what krtek has written. More specifically solution 1:


  • you've committed one (!) changeset but have not pushed it yet
  • you want to modify this changeset (e.g. add, remove or change files and/or the commit message)


  • use hg rollback to undo the last commit
  • commit again with the new changes in place

The rollback really undoes the last operation. Its way of working is quite simple: normal operations in HG will only append to files; this includes a commit. Mercurial keeps track of the file lengths of the last transaction and can therefore completely undo one step by truncating the files back to their old lengths.

Hibernate Criteria Restrictions AND / OR combination

think works

Criteria criteria = getSession().createCriteria(clazz); 
Criterion rest1= Restrictions.and(Restrictions.eq(A, "X"), 
 "B", Arrays.asList("X",Y)));
Criterion rest2= Restrictions.and(Restrictions.eq(A, "Y"), 
           Restrictions.eq(B, "Z"));
criteria.add(Restrictions.or(rest1, rest2));

How do I add multiple "NOT LIKE '%?%' in the WHERE clause of sqlite3?

this is a select command

    application_key = 'dsfdsfdjsfdsf'
        AND email NOT LIKE ''
        AND email NOT LIKE ''
        AND email NOT LIKE '';

this update command

 UPDATE user
    SET email = null
    WHERE application_key='dsfdsfdjsfdsf' and  email not like '' 
    and email not like ''  and email not like '';

MongoDB running but can't connect using shell

You may want to check your config to see if the bind_ip is set


If it is then this permits only local logins. Comment this out and restart mongo, this may help.

Call to getLayoutInflater() in places not in activity

Using context object you can get LayoutInflater from following code

LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

Problem in running .net framework 4.0 website on iis 7.0

If you look in the ISAPI And CGI Restrictions, and everything is already set to Allowed, and the ASP.NET installed is v4.0.30319, then in the right, at the "Actions" panel click in the "Edit Feature Settings..." and check both boxes. In my case, they were not.

jQuery Ajax requests are getting cancelled without being sent

If anyone else runs into this, the issue we had was that we were making the ajax request from a link, and not preventing the link from being followed. So if you are doing this in an onclick attribute, make sure to return false; as well.

What is the recommended way to make a numeric TextField in JavaFX?

Update Apr 2016

This answer was created some years ago and the original answer is largely obsolete now.

Since Java 8u40, Java has a TextFormatter which is usually best for enforcing input of specific formats such as numerics on JavaFX TextFields:

See also other answers to this question which specifically mention TextFormatter.

Original Answer

There are some examples of this in this gist, I have duplicated one of the examples below:

// helper text field subclass which restricts text input to a given range of natural int numbers
// and exposes the current numeric int value of the edit box as a value property.
class IntField extends TextField {
  final private IntegerProperty value;
  final private int minValue;
  final private int maxValue;

  // expose an integer value property for the text field.
  public int  getValue()                 { return value.getValue(); }
  public void setValue(int newValue)     { value.setValue(newValue); }
  public IntegerProperty valueProperty() { return value; }

  IntField(int minValue, int maxValue, int initialValue) {
    if (minValue > maxValue) 
      throw new IllegalArgumentException(
        "IntField min value " + minValue + " greater than max value " + maxValue
    if (maxValue < minValue) 
      throw new IllegalArgumentException(
        "IntField max value " + minValue + " less than min value " + maxValue
    if (!((minValue <= initialValue) && (initialValue <= maxValue))) 
      throw new IllegalArgumentException(
        "IntField initialValue " + initialValue + " not between " + minValue + " and " + maxValue

    // initialize the field values.
    this.minValue = minValue;
    this.maxValue = maxValue;
    value = new SimpleIntegerProperty(initialValue);
    setText(initialValue + "");

    final IntField intField = this;

    // make sure the value property is clamped to the required range
    // and update the field's text to be in sync with the value.
    value.addListener(new ChangeListener<Number>() {
      @Override public void changed(ObservableValue<? extends Number> observableValue, Number oldValue, Number newValue) {
        if (newValue == null) {
        } else {
          if (newValue.intValue() < intField.minValue) {

          if (newValue.intValue() > intField.maxValue) {

          if (newValue.intValue() == 0 && (textProperty().get() == null || "".equals(textProperty().get()))) {
            // no action required, text property is already blank, we don't need to set it to 0.
          } else {

    // restrict key input to numerals.
    this.addEventFilter(KeyEvent.KEY_TYPED, new EventHandler<KeyEvent>() {
      @Override public void handle(KeyEvent keyEvent) {
        if(intField.minValue<0) {
                if (!"-0123456789".contains(keyEvent.getCharacter())) {
            else {
                if (!"0123456789".contains(keyEvent.getCharacter())) {

    // ensure any entered values lie inside the required range.
    this.textProperty().addListener(new ChangeListener<String>() {
      @Override public void changed(ObservableValue<? extends String> observableValue, String oldValue, String newValue) {
        if (newValue == null || "".equals(newValue) || (intField.minValue<0 && "-".equals(newValue))) {

        final int intValue = Integer.parseInt(newValue);

        if (intField.minValue > intValue || intValue > intField.maxValue) {


Script to kill all connections to a database (More than RESTRICTED_USER ROLLBACK)

@AlexK wrote a great answer. I just want to add my two cents. The code below is entirely based on @AlexK's answer, the difference is that you can specify the user and a time since the last batch was executed (note that the code uses sys.dm_exec_sessions instead of master..sysprocess):

DECLARE @kill varchar(8000);
set @kill =''
select @kill = @kill + 'kill ' +  CONVERT(varchar(5), session_id) + ';' from sys.dm_exec_sessions 
where login_name = 'usrDBTest'
and datediff(hh,login_time,getdate()) > 1
--and session_id in (311,266)    

In this example only the process of the user usrDBTest which the last batch was executed more than 1 hour ago will be killed.

How to automatically allow blocked content in IE?

If you are to use the

<!-- saved from url=(0014)about:internet -->


<!-- saved from url=(0016)http://localhost -->

make sure the HTML file is saved in windows/dos format with "\r\n" as line breaks after the statement. Otherwise I couldn't make it work.

How do I restrict my EditText input to numerical (possibly decimal and signed) input?

use setRawInputType and setKeyListener

editTextNumberPicker.setRawInputType(InputType.TYPE_CLASS_NUMBER | 
                   InputType.TYPE_NUMBER_FLAG_DECIMAL|InputType.TYPE_NUMBER_FLAG_SIGNED );
editTextNumberPicker.setKeyListener(DigitsKeyListener.getInstance(false,true));//set decimals and positive numbers. 

How to run script as another user without password?

try running:

su -c "Your command right here" -s /bin/sh username

This will run the command as username given that you have permissions to sudo as that user.

Foreign key constraints: When to use ON UPDATE and ON DELETE

Addition to @MarkR answer - one thing to note would be that many PHP frameworks with ORMs would not recognize or use advanced DB setup (foreign keys, cascading delete, unique constraints), and this may result in unexpected behaviour.

For example if you delete a record using ORM, and your DELETE CASCADE will delete records in related tables, ORM's attempt to delete these related records (often automatic) will result in error.

How does Zalgo text work?

The text uses combining characters, also known as combining marks. See section 2.11 of Combining Characters in the Unicode Standard (PDF).

In Unicode, character rendering does not use a simple character cell model where each glyph fits into a box with given height. Combining marks may be rendered above, below, or inside a base character

So you can easily construct a character sequence, consisting of a base character and “combining above” marks, of any length, to reach any desired visual height, assuming that the rendering software conforms to the Unicode rendering model. Such a sequence has no meaning of course, and even a monkey could produce it (e.g., given a keyboard with suitable driver).

And you can mix “combining above” and “combining below” marks.

The sample text in the question starts with:

Hexadecimal to Integer in Java

Try this

public static long Hextonumber(String hexval)
//      String decimal="0x00000bb9";
        Long number = Long.decode(hexval);
//.......       System.out.println("String [" + hexval + "] = " + number);
        return number;

Hibernate Criteria for Dates

try this,

    String dateStr = "17-April-2011 19:20:23.707000000 ";
    Date dateForm = new SimpleDateFormat("dd-MMMM-yyyy HH:mm:ss").parse(dateStr);
    SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");  

    String newDate = format.format(dateForm);  

    Calendar today = Calendar.getInstance();
    Date fromDate = format.parse(newDate);
    today.add(Calendar.DAY_OF_YEAR, 1);
    Date toDate= new SimpleDateFormat("dd-MM-yyyy").parse(format.format(today.getTime()));

    Criteria crit = sessionFactory.getCurrentSession().createCriteria(Model.class);
    crit.add("dateFieldName", fromDate));
    crit.add(Restrictions.le("dateFieldName", toDate));
    return crit.list();

Make DateTimePicker work as TimePicker only in WinForms

You want to set its 'Format' property to be time and add a spin button control to it:

yourDateTimeControl.Format = DateTimePickerFormat.Time;
yourDateTimeControl.ShowUpDown = true;

import sun.misc.BASE64Encoder results in error compiled in Eclipse

This error (or warning in later versions) occurs because you are compiling against a Java Execution Environment. This shows up as JRE System library [CDC-1.0/Foundation-1.0] in the Build path of your Eclipse Java project. Such environments only expose the Java standard API instead of all the classes within the runtime. This means that the classes used to implement the Java standard API are not exposed.

You can allow access to these particular classes using access rules, you could configure Eclipse to use the JDK directly or you could disable the error. You would however be hiding a serious error as Sun internal classes shouldn't be used (see below for a short explanation).

Java contains a Base64 class in the standard API since Java 1.8. See below for an example how to use it:

Java 8 import statement:

import java.util.Base64;

Java 8 example code:

// create a byte array containing data (test)
byte[] binaryData = new byte[] { 0x64, 0x61, 0x74, 0x61 };
// create and configure encoder (using method chaining) 
Base64.Encoder base64Encoder = Base64.getEncoder().withoutPadding();
// encode to string (instead of a byte array containing ASCII)
String base64EncodedData = base64Encoder.encodeToString(binaryData);

// decode using a single statement (no reuse of decoder)
// NOTE the decoder won't fail because the padding is missing
byte[] base64DecodedData = Base64.getDecoder().decode(base64EncodedData);

If Java 8 is not available a library such as Apache Commons Codec or Guava should be used.

Sun internal classes shouldn't be used. Those classes are used to implement Java. They have got public methods to allow instantiation from other packages. A good build environment however should protect you from using them.

Using internal classes may break compatibility with future Java SE runtimes; the implementation and location of these classes can change at any time. It should be strongly discouraged to disable the error or warning (but the disabling of the error is suggested in previous answers, including the two top voted ones).

failed to lazily initialize a collection of role

Try swich fetchType from LAZY to EAGER

private Set<NodeValue> nodeValues;

But in this case your app will fetch data from DB anyway. If this query very hard - this may impact on performance. More here:

==> 73

how to properly display an iFrame in mobile safari

Yeah, you can't constrain the iframe itself with height and width. You should put a div around it. If you control the content in the iframe, you can put some JS within the iframe content that will tell the parent to scroll the div when the touch event is received.

like this:

The JS:

setTimeout(function () {
var startY = 0;
var startX = 0;
var b = document.body;
b.addEventListener('touchstart', function (event) {
    parent.window.scrollTo(0, 1);
    startY = event.targetTouches[0].pageY;
    startX = event.targetTouches[0].pageX;
b.addEventListener('touchmove', function (event) {
    var posy = event.targetTouches[0].pageY;
    var h = parent.document.getElementById("scroller");
    var sty = h.scrollTop;

    var posx = event.targetTouches[0].pageX;
    var stx = h.scrollLeft;
    h.scrollTop = sty - (posy - startY);
    h.scrollLeft = stx - (posx - startX);
    startY = posy;
    startX = posx;
}, 1000);


<div id="scroller" style="height: 400px; width: 100%; overflow: auto;">
<iframe height="100%" id="iframe" scrolling="no" width="100%" id="iframe" src="url" />

If you don't control the iframe content, you can use an overlay over the iframe in a similar manner, but then you can't interact with the iframe contents other than to scroll it - so you can't, for example, click links in the iframe.

It used to be that you could use two fingers to scroll within an iframe, but that doesn't work anymore.

Update: iOS 6 broke this solution for us. I've been attempting to get a new fix for it, but nothing has worked yet. In addition, it is no longer possible to debug javascript on the device since they introduced Remote Web Inspector, which requires a Mac to use.

How to get a complete list of ticker symbols from Yahoo Finance?

There is a nice C# wrapper for the Yahoo.Finance API at that will get you there. Unfortunately there is no direct way to download the ticker list but the following creates the list by iterating through the alphabetical groups:

        AlphabeticIDIndexDownload dl1 = new AlphabeticIDIndexDownload();
        dl1.Settings.TopIndex = null;
        Response<AlphabeticIDIndexResult> resp1 = dl1.Download();


        foreach (var alphabeticalIndex in resp1.Result.Items)
            AlphabeticalTopIndex topIndex = (AlphabeticalTopIndex) alphabeticalIndex;
            dl1.Settings.TopIndex = topIndex;
            Response<AlphabeticIDIndexResult> resp2 = dl1.Download();

            foreach (var index in resp2.Result.Items)
                IDSearchDownload dl2 = new IDSearchDownload();
                Response<IDSearchResult> resp3 = dl2.Download(index);

                int i = 0;
                foreach (var item in resp3.Result.Items)
                    writeStream.WriteLine(item.ID + "|" + item.ISIN + "|" + item.Name + "|" + item.Exchange + "|" + item.Type + "|" + item.Industry);


It gave me a list of about 75,000 securities in about 4 mins.

How to display with n decimal places in Matlab

i use like tim say sprintf('%0.6f', x), it's a string then i change it to number by using command str2double(x).

nginx upload client_max_body_size issue

From the documentation:

It is necessary to keep in mind that the browsers do not know how to correctly show this error.

I suspect this is what's happening, if you inspect the HTTP to-and-fro using tools such as Firebug or Live HTTP Headers (both Firefox extensions) you'll be able to see what's really going on.

Use of "global" keyword in Python

While you can access global variables without the global keyword, if you want to modify them you have to use the global keyword. For example:

foo = 1
def test():
    foo = 2 # new local foo

def blub():
    global foo
    foo = 3 # changes the value of the global foo

In your case, you're just accessing the list sub.

php mail setup in xampp

My favorite smtp server is hMailServer.

It has a nice windows friendly installer and wizard. Hands down the easiest mail server I've ever setup.

It can proxy through your gmail/yahoo/etc account or send email directly.

Once it is installed, email in xampp just works with no config changes.

PowerShell on Windows 7: Set-ExecutionPolicy for regular users

If you (or a helpful admin) runs Set-ExecutionPolicy as administrator, the policy will be set for all users. (I would suggest "remoteSigned" rather than "unrestricted" as a safety measure.)

NB.: On a 64-bit OS you need to run Set-ExecutionPolicy for 32-bit and 64-bit PowerShell separately.

You can't specify target table for update in FROM clause

Just as reference, you can also use Mysql Variables to save temporary results, e.g.:

SET @v1 := (SELECT ... );
UPDATE ... SET ... WHERE x=@v1;

How to do sed like text replace with python?

If you are using Python3 the following module will help you:


Place the module file into your Python3 modules path, then:

import pysed
pysed.replace(<Old string>, <Replacement String>, <Text File>)
pysed.rmlinematch(<Unwanted string>, <Text File>)
pysed.rmlinenumber(<Unwanted Line Number>, <Text File>)

Limit file format when using <input type="file">?

You can use the change event to monitor what the user selects and notify them at that point that the file is not acceptable. It does not limit the actual list of files displayed, but it is the closest you can do client-side, besides the poorly supported accept attribute.

var file = document.getElementById('someId');_x000D_
file.onchange = function(e) {_x000D_
  var ext = this.value.match(/\.([^\.]+)$/)[1];_x000D_
  switch (ext) {_x000D_
    case 'jpg':_x000D_
    case 'bmp':_x000D_
    case 'png':_x000D_
    case 'tif':_x000D_
      alert('Not allowed');_x000D_
      this.value = '';_x000D_
<input type="file" id="someId" />


Why does Eclipse automatically add appcompat v7 library support whenever I create a new project?

According to

The ActionBar APIs were first added in Android 3.0 (API level 11) but they are also available in the Support Library for compatibility with Android 2.1 (API level 7) and above.

In short, that auto-generated project you're seeing modularizes the process of adding the ActionBar to APIs 7-10.

Example of ActionBar on Froyo

See for a simplified explanation and tutorial on the topic.

Pandas groupby month and year

You can also do it by creating a string column with the year and month as follows:

df['date'] = df.index
df['year-month'] = df['date'].apply(lambda x: str(x.year) + ' ' + str(x.month))
grouped = df.groupby('year-month')

However this doesn't preserve the order when you loop over the groups, e.g.

for name, group in grouped:

Will give:

2007 11
2007 12
2008 1
2008 10
2008 11
2008 12
2008 2
2008 3
2008 4
2008 5
2008 6
2008 7
2008 8
2008 9
2009 1
2009 10

So then, if you want to preserve the order, you must do as suggested by @Q-man above:

grouped = df.groupby([df.index.year, df.index.month])

This will preserve the order in the above loop:

(2007, 11)
(2007, 12)
(2008, 1)
(2008, 2)
(2008, 3)
(2008, 4)
(2008, 5)
(2008, 6)
(2008, 7)
(2008, 8)
(2008, 9)
(2008, 10)

accessing a file using [NSBundle mainBundle] pathForResource: ofType:inDirectory:

Try this, it's working for me.

NSString *str = [[[NSBundle mainBundle] resourcePath] stringByAppendingPathComponent:@"paylines.txt"];  

For simulator

NSURL *rtfUrl = [[NSBundle mainBundle] URLForResource:@"paylines" withExtension:@".txt"];

Egit rejected non-fast-forward

I have found that you must be on the latest commit of the git. So these are the steps to take: 1) make sure you have not been working on the same files, otherwise you will run into a DITY_WORK_TREE error. 2) pull the latest changes. 3) commit your updates.

Hope this helps.

Is there a typical state machine implementation pattern?

You might have seen my answer to another C question where I mentioned FSM! Here is how I do it:

  STATE(x) {

  STATE(y) {
    if (x == 0) 

With the following macros defined

#define FSM
#define STATE(x)      s_##x :
#define NEXTSTATE(x)  goto s_##x

This can be modified to suit the specific case. For example, you may have a file FSMFILE that you want to drive your FSM, so you could incorporate the action of reading next char into the the macro itself:

#define FSM
#define STATE(x)         s_##x : FSMCHR = fgetc(FSMFILE); sn_##x :
#define NEXTSTATE(x)     goto s_##x
#define NEXTSTATE_NR(x)  goto sn_##x

now you have two types of transitions: one goes to a state and read a new character, the other goes to a state without consuming any input.

You can also automate the handling of EOF with something like:

#define STATE(x)  s_##x  : if ((FSMCHR = fgetc(FSMFILE) == EOF)\
                             goto sx_endfsm;\
                  sn_##x :

#define ENDFSM    sx_endfsm:

The good thing of this approach is that you can directly translate a state diagram you draw into working code and, conversely, you can easily draw a state diagram from the code.

In other techniques for implementing FSM the structure of the transitions is buried in control structures (while, if, switch ...) and controlled by variables value (tipically a state variable) and it may be a complex task to relate the nice diagram to a convoluted code.

I learned this technique from an article appeared on the great "Computer Language" magazine that, unfortunately, is no longer published.

Responsive design with media query : screen size?

i will provide mine because @muni s solution was a bit overkill for me

note: if you want to add custom definitions for several resolutions together, say something like this:

//mobile generally   
 @media screen and (max-width: 1199)  {

        display: none;

        display: initial;


Be sure to add those definitions on top of the accurate definitions, so it cascades correctly (e.g. 'smartphone portrait' must win versus 'mobile generally')

//here all definitions to apply globally

@media only screen
and (min-width : 1200) {


//tablet landscape
@media screen and (min-width: 1024px) and (max-width: 1600px)  {

} // end media query

//tablet portrait
@media screen and (min-width: 768px) and (max-width: 1023px)  {

}//end media definition

//smartphone landscape
@media screen and (min-width: 480px) and (max-width: 767px)  {

}//end media query

//smartphone portrait
@media screen /*and (min-width: 320px)*/
and (max-width: 479px) {


//end media query

How to enable named/bind/DNS full logging?

Run command rndc querylog on or add querylog yes; to options{}; section in named.conf to activate that channel.

Also make sure you’re checking correct directory if your bind is chrooted.

jQuery validation plugin: accept only alphabetical characters?

If you include the additional methods file, here's the current file for 1.7:

You can use the lettersonly rule :) The additional methods are part of the zip you download, you can always find the latest here.

Here's an example:

  rules: {
    myField: { lettersonly: true }

It's worth noting, each additional method is independent, you can include that specific one, just place this before your .validate() call:

jQuery.validator.addMethod("lettersonly", function(value, element) {
  return this.optional(element) || /^[a-z]+$/i.test(value);
}, "Letters only please"); 

Numpy - Replace a number with NaN


A==NDV will produce a boolean array that can be used as an index for A

In Excel how to get the left 5 characters of each cell in a specified column and put them into a new column

I find, if the data is imported, you may need to use the trim command on top of it, to get your details. =LEFT(TRIM(B2),8) In my case, I was using it to find a IP range. with mask, so response is: 10.3.44 Kind of handy.

How to use variables in SQL statement in Python?

Be careful when you simply append values of variables to your statements: Imagine a user naming himself ';DROP TABLE Users;' -- That's why you need to use sql escaping, which Python provides for you when you use the cursor.execute in a decent manner. Example in the url is:

cursor.execute("insert into Attendees values (?, ?, ?)", (name,
seminar, paid) )

Using colors with printf

Rather than using archaic terminal codes, may I suggest the following alternative. Not only does it provide more readable code, but it also allows you to keep the color information separate from the format specifiers just as you originally intended.

blue=$(tput setaf 4)
normal=$(tput sgr0)

printf "%40s\n" "${blue}This text is blue${normal}"

See my answer HERE for additional colors

"401 Unauthorized" on a directory

You do not have permision to view this directory or page using the credentials that you supplied.

This happened despite the fact the user is already authenticated via Active Directory.

There can be many causes to Access Denied error, but if you think you’ve already configured everything correctly from your web application, there might be a little detail that’s forgotten. Make sure you give the proper permission to Authenticated Users to access your web application directory.

Here are the steps I took to solve this issue.

  1. Right-click on the directory where the web application is stored and select Properties and click on Security tab.

  2. Click on Click on Edit…, then Add… button. Type in Authenticated Users in the Enter the object names to select., then Add button. Type in Authenticated Users in the Enter the object names to select.

  3. Click OK and you should see Authenticated Users as one of the user names. Give proper permissions on the Permissions for Authenticated Users box on the lower end if they’re not checked already.

  4. Click OK twice to close the dialog box. It should take effect immediately, but if you want to be sure, you can restart IIS for your web application.

Refresh your browser and it should display the web page now.

Hope this helps!

Are 2 dimensional Lists possible in c#?

I used:

List<List<String>> List1 = new List<List<String>>
var List<int> = new List<int>();
var List<int> = new List<int>();

that equals:

[0] => List2 // List1[0][x]
        [0] => Test  // List[0][0] etc.
        [1] => Test2

[1] => List2
        [0] => Test3

How can I loop through all rows of a table? (MySQL)

Mr Purple's example I used in mysql trigger like that,

Select COUNT(*) from user where deleted_at is null INTO n;
SET i=0;
  INSERT INTO user_notification(notification_id,status,userId)values(new.notification_id,1,(Select userId FROM user LIMIT i,1)) ;
  SET i = i + 1;

How can I add some small utility functions to my AngularJS application?

EDIT 7/1/15:

I wrote this answer a pretty long time ago and haven't been keeping up a lot with angular for a while, but it seems as though this answer is still relatively popular, so I wanted to point out that a couple of the point @nicolas makes below are good. For one, injecting $rootScope and attaching the helpers there will keep you from having to add them for every controller. Also - I agree that if what you're adding should be thought of as Angular services OR filters, they should be adopted into the code in that manner.

Also, as of the current version 1.4.2, Angular exposes a "Provider" API, which is allowed to be injected into config blocks. See these resources for more:

AngularJS dependency injection of value inside of module.config

I don't think I'm going to update the actual code blocks below, because I'm not really actively using Angular these days and I don't really want to hazard a new answer without feeling comfortable that it's actually conforming to new best practices. If someone else feels up to it, by all means go for it.

EDIT 2/3/14:

After thinking about this and reading some of the other answers, I actually think I prefer a variation of the method brought up by @Brent Washburne and @Amogh Talpallikar. Especially if you're looking for utilities like isNotString() or similar. One of the clear advantages here is that you can re-use them outside of your angular code and you can use them inside of your config function (which you can't do with services).

That being said, if you're looking for a generic way to re-use what should properly be services, the old answer I think is still a good one.

What I would do now is:


var MyNamespace = MyNamespace || {};

 MyNamespace.helpers = {
   isNotString: function(str) {
     return (typeof str !== "string");

 angular.module('app', ['app.controllers', '']).                             
   config(['$routeProvider', function($routeProvider) {
     // Routing stuff here...


angular.module('app.controllers', []).                                                                                                                                                                                  
  controller('firstCtrl', ['$scope', function($scope) {
    $scope.helpers = MyNamespace.helpers;

Then in your partial you can use:

<button data-ng-click="console.log(helpers.isNotString('this is a string'))">Log String Test</button>

Old answer below:

It might be best to include them as a service. If you're going to re-use them across multiple controllers, including them as a service will keep you from having to repeat code.

If you'd like to use the service functions in your html partial, then you should add them to that controller's scope:

$scope.doSomething = ServiceName.functionName;

Then in your partial you can use:

<button data-ng-click="doSomething()">Do Something</button>

Here's a way you might keep this all organized and free from too much hassle:

Separate your controller, service and routing code/config into three files: controllers.js, services.js, and app.js. The top layer module is "app", which has app.controllers and as dependencies. Then app.controllers and can be declared as modules in their own files. This organizational structure is just taken from Angular Seed:


 angular.module('app', ['app.controllers', '']).                             
   config(['$routeProvider', function($routeProvider) {
     // Routing stuff here...


 /* Generic Services */                                                                                                                                                                                                    
 angular.module('', [])                                                                                                                                                                        
   .factory("genericServices", function() {                                                                                                                                                   
     return {                                                                                                                                                                                                              
       doSomething: function() {   
         //Do something here
       doSomethingElse: function() {
         //Do something else here


angular.module('app.controllers', []).                                                                                                                                                                                  
  controller('firstCtrl', ['$scope', 'genericServices', function($scope, genericServices) {
    $scope.genericServices = genericServices;

Then in your partial you can use:

<button data-ng-click="genericServices.doSomething()">Do Something</button>
<button data-ng-click="genericServices.doSomethingElse()">Do Something Else</button>

That way you only add one line of code to each controller and are able to access any of the services functions wherever that scope is accessible.

Preventing HTML and Script injections in Javascript

I use this function htmlentities($string):

$msg = "<script>alert("hello")</script> <h1> Hello World </h1>"
$msg = htmlentities($msg);
echo $msg;

Python Error: unsupported operand type(s) for +: 'int' and 'NoneType'

In your giant elif chain, you skipped 13. You might want to throw an error if you hit the end of the chain without returning anything, to catch numbers you missed and incorrect calls of the function:

elif x == 90:
    return 6
    raise ValueError(x)

MVC 3 file upload and model binding

Your form doesn't contain any input tag other than the file so in your controller action you cannot expect to get anything else than the uploaded file (that's all that's being sent to the server). One way to achieve this would be to include a hidden tag containing the id of the model which will allow you to retrieve it from your datastore inside the controller action you are posting to (use this if the user is not supposed to modify the model but simply attach a file):

@using (Html.BeginForm("Uploadfile", "Containers", FormMethod.Post, new { enctype = "multipart/form-data" }))
    @Html.HiddenFor(x => x.Id)
    <input type="file" name="file" id="file" />
    <input type="submit" value="submit" />

and then in your controller action:

public ActionResult Uploadfile(int id, HttpPostedFileBase file)
    Containers containers = Repository.GetContainers(id);

On the other hand if you wanted to allow the user to modify this model then you will need to include the proper input fields for each field of your model that you want to be sent to the server:

@using (Html.BeginForm("Uploadfile", "Containers", FormMethod.Post, new { enctype = "multipart/form-data" }))
    @Html.TextBoxFor(x => x.Prop1)
    @Html.TextBoxFor(x => x.Prop2)
    @Html.TextBoxFor(x => x.Prop3)
    <input type="file" name="file" id="file" />
    <input type="submit" value="submit" />

and then you will have the default model binder reconstruct this model from the request:

public ActionResult Uploadfile(Container containers, HttpPostedFileBase file)

How to get a jqGrid selected row cells value

First you can get the rowid of the selected row with respect of getGridParam method and 'selrow' as the parameter and then you can use getCell to get the cell value from the corresponding column:

var myGrid = $('#list'),
    selRowId = myGrid.jqGrid ('getGridParam', 'selrow'),
    celValue = myGrid.jqGrid ('getCell', selRowId, 'columnName');

The 'columnName' should be the same name which you use in the 'name' property of the colModel. If you need values from many column of the selected row you can use getRowData instead of getCell.

Best way to get child nodes

firstElementChild might not be available in IE<9 (only firstChild)

on IE<9 firstChild is the firstElementChild because MS DOM (IE<9) is not storing empty text nodes. But if you do so on other browsers they will return empty text nodes...

my solution


this will give the firstchild even on IE<9

Directory.GetFiles: how to get only filename, not full path?


  string[] files =  new DirectoryInfo(dir).GetFiles().Select(o => o.Name).ToArray();

Above line may throw UnauthorizedAccessException. To handle this check out below link

C# Handle System.UnauthorizedAccessException in LINQ

Reliable method to get machine's MAC address in C#

We use WMI to get the mac address of the interface with the lowest metric, e.g. the interface windows will prefer to use, like this:

public static string GetMACAddress()
    ManagementObjectSearcher searcher = new ManagementObjectSearcher("SELECT * FROM Win32_NetworkAdapterConfiguration where IPEnabled=true");
    IEnumerable<ManagementObject> objects = searcher.Get().Cast<ManagementObject>();
    string mac = (from o in objects orderby o["IPConnectionMetric"] select o["MACAddress"].ToString()).FirstOrDefault();
    return mac;

Or in Silverlight (needs elevated trust):

public static string GetMACAddress()
    string mac = null;
    if ((Application.Current.IsRunningOutOfBrowser) && (Application.Current.HasElevatedPermissions) && (AutomationFactory.IsAvailable))
        dynamic sWbemLocator = AutomationFactory.CreateObject("WbemScripting.SWBemLocator");
        dynamic sWbemServices = sWbemLocator.ConnectServer(".");
        sWbemServices.Security_.ImpersonationLevel = 3; //impersonate

        string query = "SELECT * FROM Win32_NetworkAdapterConfiguration where IPEnabled=true";
        dynamic results = sWbemServices.ExecQuery(query);

        int mtu = int.MaxValue;
        foreach (dynamic result in results)
            if (result.IPConnectionMetric < mtu)
                mtu = result.IPConnectionMetric;
                mac = result.MACAddress;
    return mac;

Android Studio don't generate for my import project

I had a similar problem in a large multi-module project with many dependencies among the modules. What worked for me, was to attempt to build separately from command line all the modules that failed to build within Android Studio. That gave me indications on resources missing in each project. From the project level in my console I did:

$ cd moduleName
$ ../gradlew assembleDebug

This provided me with a number of 'No resource found that matches the given name' errors, that weren't shown before, when I build the project as a whole.

Show Current Location and Update Location in MKMapView in Swift

you have to override CLLocationManager.didUpdateLocations

 func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {

    let userLocation:CLLocation = locations[0] as CLLocation

    let location = CLLocationCoordinate2D(latitude: userLocation.coordinate.latitude, longitude: userLocation.coordinate.longitude)

    let span = MKCoordinateSpanMake(0.5, 0.5)

    let region = MKCoordinateRegion (center:  location,span: span)

    mapView.setRegion(region, animated: true)

you also have to add NSLocationWhenInUseUsageDescription and NSLocationAlwaysUsageDescription to your plist setting Result as value

Find files with size in Unix

find . -size +10000k -exec ls -sd {} +

If your version of find won't accept the + notation (which acts rather like xargs does), then you might use (GNU find and xargs, so find probably supports + anyway):

find . -size +10000k -print0 | xargs -0 ls -sd

or you might replace the + with \; (and live with the relative inefficiency of this), or you might live with problems caused by spaces in names and use the portable:

find . -size +10000k -print | xargs ls -sd

The -d on the ls commands ensures that if a directory is ever found (unlikely, but...), then the directory information will be printed, not the files in the directory. And, if you're looking for files more than 1 MB (as a now-deleted comment suggested), you need to adjust the +10000k to 1000k or maybe +1024k, or +2048 (for 512-byte blocks, the default unit for -size). This will list the size and then the file name. You could avoid the need for -d by adding -type f to the find command, of course.

Entity Framework Code First - two Foreign Keys from same table

InverseProperty in EF Core makes the solution easy and clean.


So the desired solution would be:

public class Team
    public int TeamId { get; set;} 
    public string Name { get; set; }

    public ICollection<Match> HomeMatches{ get; set; }

    public ICollection<Match> AwayMatches{ get; set; }

public class Match
    public int MatchId { get; set; }

    [ForeignKey(nameof(HomeTeam)), Column(Order = 0)]
    public int HomeTeamId { get; set; }
    [ForeignKey(nameof(GuestTeam)), Column(Order = 1)]
    public int GuestTeamId { get; set; }

    public float HomePoints { get; set; }
    public float GuestPoints { get; set; }
    public DateTime Date { get; set; }

    public Team HomeTeam { get; set; }
    public Team GuestTeam { get; set; }

How to increase time in web.config for executing sql query

You should add the httpRuntime block and deal with executionTimeout (in seconds).

<?xml version="1.0" encoding="utf-8" ?>
   <httpRuntime executionTimeout="90" maxRequestLength="4096"
    appRequestQueueLimit="100" />

For more information, please, see msdn page.

How do I find the time difference between two datetime objects in python?

Just thought it might be useful to mention formatting as well in regards to timedelta. strptime() parses a string representing a time according to a format.

from datetime import datetime

datetimeFormat = '%Y/%m/%d %H:%M:%S.%f'    
time1 = '2016/03/16 10:01:28.585'
time2 = '2016/03/16 09:56:28.067'  
time_dif = datetime.strptime(time1, datetimeFormat) - datetime.strptime(time2,datetimeFormat)

This will output: 0:05:00.518000

How to search a Git repository by commit message?


git log --oneline --grep='Searched phrase'

or this:

git log --oneline --name-status --grep='Searched phrase'

commands work best for me.

Subtract days from a DateTime

You can use the following code:

dateForButton = dateForButton.Subtract(TimeSpan.FromDays(1));

Background blur with CSS

Use an empty element sized for the content as the background, and position the content over the blurred element.


  position: absolute;
  top: 40%;
  left: 50%;
  z-index: 50;
  margin-left: -200px;
  height: 200px;
  width: 400px;


  background: transparent;
  position: absolute;
  top: 40%;
  left: 50%;
  margin-left -200px;
  overflow: hidden;
  z-index: 51;

The background element can be inside of the content element, but not the other way around.

<div id='dialog_base'></div>
<div id='dialog_content'>
    Some Content
    <!-- Alternatively with z-index: <div id='dialog_base'></div> -->

This is not easy if the content is not always consistently sized, but it works.

How to do a Jquery Callback after form submit?

For MVC here was an even easier approach. You need to use the Ajax form and set the AjaxOptions

@using (Ajax.BeginForm("UploadTrainingMedia", "CreateTest", new AjaxOptions() { HttpMethod = "POST", OnComplete = "displayUploadMediaMsg" }, new { enctype = "multipart/form-data", id = "frmUploadTrainingMedia" }))
  ... html for form

here is the submission code, this is in the document ready section and ties the onclick event of the button to to submit the form


here is the callback referenced in the AjaxOptions

function displayUploadMediaMsg(d){
    var rslt = $.parseJSON(d.responseText);
    if (rslt.statusCode == 200){
        $().toastmessage("showSuccessToast", rslt.status);
        $().toastmessage("showErrorToast", rslt.status);

in the controller method for MVC it looks like this

public JsonResult UploadTrainingMedia(IEnumerable<HttpPostedFileBase> files)
    if (files != null)
        foreach (var file in files)
            // there is only one file  ... do something with it
        return Json(new
            statusCode = 200,
            status = "File uploaded",
            file = "",
        }, "text/html");
        return Json(new
            statusCode = 400,
            status = "Unable to upload file",
            file = "",
        }, "text/html");

Checking if a string is empty or null in Java


if(!Strings.isNullOrEmpty(String str)) {
   // Do your stuff here 

SQL: Two select statements in one query

You can do something like this:

    name, games, goals
    FROM tblMadrid WHERE name = 'ronaldo')
    name, games, goals
    FROM tblBarcelona WHERE name = 'messi')
ORDER BY goals;

See, for example:

Rank function in MySQL

A tweak of Daniel's version to calculate percentile along with rank. Also two people with same marks will get the same rank.

set @totalStudents = 0;
select count(*) into @totalStudents from marksheets;
SELECT id, score, @curRank := IF(@prevVal=score, @curRank, @studentNumber) AS rank, 
@percentile := IF(@prevVal=score, @percentile, (@totalStudents - @studentNumber + 1)/(@totalStudents)*100),
@studentNumber := @studentNumber + 1 as studentNumber, 
FROM marksheets, (
SELECT @curRank :=0, @prevVal:=null, @studentNumber:=1, @percentile:=100
) r

Results of the query for a sample data -

| id | score | rank | percentile    | studentNumber | @prevVal:=score |
| 10 |    98 |    1 | 100.000000000 |             2 |              98 |
|  5 |    95 |    2 |  90.000000000 |             3 |              95 |
|  6 |    91 |    3 |  80.000000000 |             4 |              91 |
|  2 |    91 |    3 |  80.000000000 |             5 |              91 |
|  8 |    90 |    5 |  60.000000000 |             6 |              90 |
|  1 |    90 |    5 |  60.000000000 |             7 |              90 |
|  9 |    84 |    7 |  40.000000000 |             8 |              84 |
|  3 |    83 |    8 |  30.000000000 |             9 |              83 |
|  4 |    72 |    9 |  20.000000000 |            10 |              72 |
|  7 |    60 |   10 |  10.000000000 |            11 |              60 |

java.math.BigInteger cannot be cast to java.lang.Long

Your error might be in this line:

List<Long> result = query.list();

where query.list() is returning a BigInteger List instead of Long list. Try to change it to.

List<BigInteger> result = query.list();

Assignment inside lambda expression in Python

The pythonic way to track state during iteration is with generators. The itertools way is quite hard to understand IMHO and trying to hack lambdas to do this is plain silly. I'd try:

def keep_last_empty(input):
    last = None
    for item in iter(input):
        if yield item
        else: last = item
    if last is not None: yield last

output = list(keep_last_empty(input))

Overall, readability trumps compactness every time.

Spring: How to get parameters from POST body?

You can get param from request.

public ResponseEntity<Boolean> saveData(HttpServletRequest request,
            HttpServletResponse response, Model model){
   String jsonString = request.getParameter("json");

Java Delegates?

No, but it has similar behavior, internally.

In C# delegates are used to creates a separate entry point and they work much like a function pointer.

In java there is no thing as function pointer (on a upper look) but internally Java needs to do the same thing in order to achieve these objectives.

For example, creating threads in Java requires a class extending Thread or implementing Runnable, because a class object variable can be used a memory location pointer.

Fast and simple String encrypt/decrypt in JAVA

Java - encrypt / decrypt user name and password from a configuration file

Code from above link

DESKeySpec keySpec = new DESKeySpec("Your secret Key phrase".getBytes("UTF8"));
SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
SecretKey key = keyFactory.generateSecret(keySpec);
sun.misc.BASE64Encoder base64encoder = new BASE64Encoder();
sun.misc.BASE64Decoder base64decoder = new BASE64Decoder();

// ENCODE plainTextPassword String
byte[] cleartext = plainTextPassword.getBytes("UTF8");      

Cipher cipher = Cipher.getInstance("DES"); // cipher is not thread safe
cipher.init(Cipher.ENCRYPT_MODE, key);
String encryptedPwd = base64encoder.encode(cipher.doFinal(cleartext));
// now you can store it 

// DECODE encryptedPwd String
byte[] encrypedPwdBytes = base64decoder.decodeBuffer(encryptedPwd);

Cipher cipher = Cipher.getInstance("DES");// cipher is not thread safe
cipher.init(Cipher.DECRYPT_MODE, key);
byte[] plainTextPwdBytes = (cipher.doFinal(encrypedPwdBytes));

Save each sheet in a workbook to separate CSV files

And here's my solution should work with Excel > 2000, but tested only on 2007:

Private Sub SaveAllSheetsAsCSV()
On Error GoTo Heaven

' each sheet reference
Dim Sheet As Worksheet
' path to output to
Dim OutputPath As String
' name of each csv
Dim OutputFile As String

Application.ScreenUpdating = False
Application.DisplayAlerts = False
Application.EnableEvents = False

' ask the user where to save
OutputPath = InputBox("Enter a directory to save to", "Save to directory", Path)

If OutputPath <> "" Then

    ' save for each sheet
    For Each Sheet In Sheets

        OutputFile = OutputPath & "\" & Sheet.Name & ".csv"

        ' make a copy to create a new book with this sheet
        ' otherwise you will always only get the first sheet
        ' this copy will now become active
        ActiveWorkbook.SaveAs FileName:=OutputFile, FileFormat:=xlCSV, CreateBackup:=False

End If

Application.ScreenUpdating = True
Application.DisplayAlerts = True
Application.EnableEvents = True

Exit Sub

MsgBox "Couldn't save all sheets to CSV." & vbCrLf & _
        "Source: " & Err.Source & " " & vbCrLf & _
        "Number: " & Err.Number & " " & vbCrLf & _
        "Description: " & Err.Description & " " & vbCrLf

GoTo Finally
End Sub

(OT: I wonder if SO will replace some of my minor blogging)

How can query string parameters be forwarded through a proxy_pass with nginx?

github gist

#set $token "?"; # deprecated

set $token ""; # declar token is ""(empty str) for original request without args,because $is_args concat any var will be `?`

if ($is_args) { # if the request has args update token to "&"
    set $token "&";

location /test {
    set $args "${args}${token}k1=v1&k2=v2"; # update original append custom params with $token
    # if no args $is_args is empty str,else it's "?"
    # http is scheme
    # service is upstream server
    #proxy_pass http://service/$uri$is_args$args; # deprecated remove `/`
    proxy_pass http://service$uri$is_args$args; # proxy pass

#http://localhost/test?foo=bar ==> http://service/test?foo=bar&k1=v1&k2=v2

#http://localhost/test/ ==> http://service/test?k1=v1&k2=v2

Mocking a function to raise an Exception to test an except block

Your mock is raising the exception just fine, but the error.resp.status value is missing. Rather than use return_value, just tell Mock that status is an attribute:

barMock.side_effect = HttpError(mock.Mock(status=404), 'not found')

Additional keyword arguments to Mock() are set as attributes on the resulting object.

I put your foo and bar definitions in a my_tests module, added in the HttpError class so I could use it too, and your test then can be ran to success:

>>> from my_tests import foo, HttpError
>>> import mock
>>> with mock.patch('') as barMock:
...     barMock.side_effect = HttpError(mock.Mock(status=404), 'not found')
...     result =
404 - 
>>> result is None

You can even see the print '404 - %s' % error.message line run, but I think you wanted to use error.content there instead; that's the attribute HttpError() sets from the second argument, at any rate.

How to use Checkbox inside Select Option

Only add class create div and add class form-control. iam use JSP,boostrap4. Ignore c:foreach.

<div class="multi-select form-control" style="height:107.292px;">
        <div class="checkbox" id="checkbox-expedientes">
            <c:forEach var="item" items="${postulantes}">
                <label class="form-check-label">
                    <input id="options" class="postulantes" type="checkbox" value="1">Option 1</label>

How to extend / inherit components?

You can inherit @Input, @Output, @ViewChild, etc. Look at the sample:

    template: ''
export class BaseComponent {
    @Input() someInput: any = 'something';

    @Output() someOutput: EventEmitter<void> = new EventEmitter<void>();


    selector: 'app-derived',
    template: '<div (click)="someOutput.emit()">{{someInput}}</div>',
    providers: [
        { provide: BaseComponent, useExisting: DerivedComponent }
export class DerivedComponent {


Iterator Loop vs index loop

Iterators make your code more generic.
Every standard library container provides an iterator hence if you change your container class in future the loop wont be affected.

Remove a file from the list that will be committed

git rm --cached will remove it from the commit set ("un-adding" it); that sounds like what you want.

Selecting multiple items in ListView

You have to select the option in ArrayAdapter:

ArrayAdapter<String> adapter = new ArrayAdapter<String>
    (this, android.R.layout.simple_list_item_single_choice, countries);

Getting RSA private key from PEM BASE64 Encoded private key file

You will find below some code for reading unencrypted RSA keys encoded in the following formats:

  • PKCS#8 PEM (-----BEGIN PRIVATE KEY-----)
  • PKCS#8 DER (binary)

It works with Java 7+ (and after 9) and doesn't use third-party libraries (like BouncyCastle) or internal Java APIs (like DerInputStream or DerValue).

private static final String PKCS_1_PEM_HEADER = "-----BEGIN RSA PRIVATE KEY-----";
private static final String PKCS_1_PEM_FOOTER = "-----END RSA PRIVATE KEY-----";
private static final String PKCS_8_PEM_HEADER = "-----BEGIN PRIVATE KEY-----";
private static final String PKCS_8_PEM_FOOTER = "-----END PRIVATE KEY-----";

public static PrivateKey loadKey(String keyFilePath) throws GeneralSecurityException, IOException {
    byte[] keyDataBytes = Files.readAllBytes(Paths.get(keyFilePath));
    String keyDataString = new String(keyDataBytes, StandardCharsets.UTF_8);

    if (keyDataString.contains(PKCS_1_PEM_HEADER)) {
        // OpenSSL / PKCS#1 Base64 PEM encoded file
        keyDataString = keyDataString.replace(PKCS_1_PEM_HEADER, "");
        keyDataString = keyDataString.replace(PKCS_1_PEM_FOOTER, "");
        return readPkcs1PrivateKey(Base64.decodeBase64(keyDataString));

    if (keyDataString.contains(PKCS_8_PEM_HEADER)) {
        // PKCS#8 Base64 PEM encoded file
        keyDataString = keyDataString.replace(PKCS_8_PEM_HEADER, "");
        keyDataString = keyDataString.replace(PKCS_8_PEM_FOOTER, "");
        return readPkcs8PrivateKey(Base64.decodeBase64(keyDataString));

    // We assume it's a PKCS#8 DER encoded binary file
    return readPkcs8PrivateKey(Files.readAllBytes(Paths.get(keyFilePath)));

private static PrivateKey readPkcs8PrivateKey(byte[] pkcs8Bytes) throws GeneralSecurityException {
    KeyFactory keyFactory = KeyFactory.getInstance("RSA", "SunRsaSign");
    PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(pkcs8Bytes);
    try {
        return keyFactory.generatePrivate(keySpec);
    } catch (InvalidKeySpecException e) {
        throw new IllegalArgumentException("Unexpected key format!", e);

private static PrivateKey readPkcs1PrivateKey(byte[] pkcs1Bytes) throws GeneralSecurityException {
    // We can't use Java internal APIs to parse ASN.1 structures, so we build a PKCS#8 key Java can understand
    int pkcs1Length = pkcs1Bytes.length;
    int totalLength = pkcs1Length + 22;
    byte[] pkcs8Header = new byte[] {
            0x30, (byte) 0x82, (byte) ((totalLength >> 8) & 0xff), (byte) (totalLength & 0xff), // Sequence + total length
            0x2, 0x1, 0x0, // Integer (0)
            0x30, 0xD, 0x6, 0x9, 0x2A, (byte) 0x86, 0x48, (byte) 0x86, (byte) 0xF7, 0xD, 0x1, 0x1, 0x1, 0x5, 0x0, // Sequence: 1.2.840.113549.1.1.1, NULL
            0x4, (byte) 0x82, (byte) ((pkcs1Length >> 8) & 0xff), (byte) (pkcs1Length & 0xff) // Octet string + length
    byte[] pkcs8bytes = join(pkcs8Header, pkcs1Bytes);
    return readPkcs8PrivateKey(pkcs8bytes);

private static byte[] join(byte[] byteArray1, byte[] byteArray2){
    byte[] bytes = new byte[byteArray1.length + byteArray2.length];
    System.arraycopy(byteArray1, 0, bytes, 0, byteArray1.length);
    System.arraycopy(byteArray2, 0, bytes, byteArray1.length, byteArray2.length);
    return bytes;


How to check whether particular port is open or closed on UNIX?

Try (maybe as root)

lsof -i -P

and grep the output for the port you are looking for.

For example to check for port 80 do

lsof -i -P | grep :80

@font-face not working

I was having this same issue and I thought I'd share my solution as I didn't see anyone address this problem specifically.

The problem was I wasn't using the correct path. My CSS looked like this:

@font-face {
font-family: 'sonhoregular';
src: url('fonts/vtkssonho-webfont.eot');
src: url('fonts/vtkssonho-webfont.eot?') format('embedded-opentype'),
     url('fonts/vtkssonho-webfont.woff2') format('woff2'),
     url('fonts/vtkssonho-webfont.woff') format('woff'),
     url('fonts/vtkssonho-webfont.ttf') format('truetype'),
     url('fonts/vtkssonho-webfont.svg#vtks_sonhoregular') format('svg');
font-weight: normal;
font-style: normal;

The problem with the path is that I am referring to the font from my CSS file, which is in my CSS folder. I needed to come up a level first, then into the fonts folder. This is what it looks like now, and works great.

@font-face {
font-family: 'sonhoregular';
src: url('../fonts/vtkssonho-webfont.eot');
src: url('../fonts/vtkssonho-webfont.eot?') format('embedded-opentype'),
     url('../fonts/vtkssonho-webfont.woff2') format('woff2'),
     url('../fonts/vtkssonho-webfont.woff') format('woff'),
     url('../fonts/vtkssonho-webfont.ttf') format('truetype'),
     url('../fonts/vtkssonho-webfont.svg#vtks_sonhoregular') format('svg');
font-weight: normal;
font-style: normal;

I hope this helps someone out!

How can I rename a project folder from within Visual Studio?

For those using Visual Studio + Git and wanting to keep the file history (works renaming both projects and/or solutions):

  1. Close Visual Studio

  2. In the .gitignore file, duplicate all ignore paths of the project you want to rename with renamed versions of those paths.

  3. Use the Git move command like this:

    git mv <old_folder_name> <new_folder_name>

    See documentation for additional options:

  4. In your .sln file: Find the line defining your project and change the folder name in path. The line should look something like:

    Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "<Project name>", "<path-to-project>\<project>.csproj"
  5. Open Visual Studio, and right click on project → Rename

  6. Afterwards, rename the namespaces.

    I read that ReSharper has some options for this. But simple find/replace did the job for me.

  7. Remove old .gitignore paths.

Swift alert view with OK and Cancel: which button tapped?

var refreshAlert = UIAlertController(title: "Log Out", message: "Are You Sure to Log Out ? ", preferredStyle: UIAlertControllerStyle.Alert)

refreshAlert.addAction(UIAlertAction(title: "Confirm", style: .Default, handler: { (action: UIAlertAction!) in

refreshAlert.addAction(UIAlertAction(title: "Cancel", style: .Default, handler: { (action: UIAlertAction!) in

    refreshAlert .dismissViewControllerAnimated(true, completion: nil)


presentViewController(refreshAlert, animated: true, completion: nil)

failed to lazily initialize a collection of role

as suggested here solving the famous LazyInitializationException is one of the following methods:

(1) Use Hibernate.initialize



You can use the JOIN FETCH syntax in your JPQL to explicitly fetch the child collection out. This is somehow like EAGER fetching.

(3) Use OpenSessionInViewFilter

LazyInitializationException often occurs in the view layer. If you use Spring framework, you can use OpenSessionInViewFilter. However, I do not suggest you to do so. It may leads to a performance issue if not used correctly.

Get unique values from a list in python

Try this function, it's similar to your code but it's a dynamic range.

def unique(a):

    while k < len(a):
        if a[k] in a[k+1:]:

    return a

Return datetime object of previous month

I think this answer is quite readable:

def month_delta(dt, delta):
    year_delta, month = divmod(dt.month + delta, 12)

    if month == 0:
        # convert a 0 to december
        month = 12
        if delta < 0:
            # if moving backwards, then it's december of last year
            year_delta -= 1

    year = dt.year + year_delta

    return dt.replace(month=month, year=year)

for delta in range(-20, 21):
    print(delta, "->", month_delta(datetime(2011, 1, 1), delta))

-20 -> 2009-05-01 00:00:00
-19 -> 2009-06-01 00:00:00
-18 -> 2009-07-01 00:00:00
-17 -> 2009-08-01 00:00:00
-16 -> 2009-09-01 00:00:00
-15 -> 2009-10-01 00:00:00
-14 -> 2009-11-01 00:00:00
-13 -> 2009-12-01 00:00:00
-12 -> 2010-01-01 00:00:00
-11 -> 2010-02-01 00:00:00
-10 -> 2010-03-01 00:00:00
-9 -> 2010-04-01 00:00:00
-8 -> 2010-05-01 00:00:00
-7 -> 2010-06-01 00:00:00
-6 -> 2010-07-01 00:00:00
-5 -> 2010-08-01 00:00:00
-4 -> 2010-09-01 00:00:00
-3 -> 2010-10-01 00:00:00
-2 -> 2010-11-01 00:00:00
-1 -> 2010-12-01 00:00:00
0 -> 2011-01-01 00:00:00
1 -> 2011-02-01 00:00:00
2 -> 2011-03-01 00:00:00
3 -> 2011-04-01 00:00:00
4 -> 2011-05-01 00:00:00
5 -> 2011-06-01 00:00:00
6 -> 2011-07-01 00:00:00
7 -> 2011-08-01 00:00:00
8 -> 2011-09-01 00:00:00
9 -> 2011-10-01 00:00:00
10 -> 2011-11-01 00:00:00
11 -> 2012-12-01 00:00:00
12 -> 2012-01-01 00:00:00
13 -> 2012-02-01 00:00:00
14 -> 2012-03-01 00:00:00
15 -> 2012-04-01 00:00:00
16 -> 2012-05-01 00:00:00
17 -> 2012-06-01 00:00:00
18 -> 2012-07-01 00:00:00
19 -> 2012-08-01 00:00:00
20 -> 2012-09-01 00:00:00

Print array elements on separate lines in Bash?

Just quote the argument to echo:

( IFS=$'\n'; echo "${my_array[*]}" )

the sub shell helps restoring the IFS after use

How to send post request with x-www-form-urlencoded body

string urlParameters = "param1=value1&param2=value2";
string _endPointName = "your url post api";

var httpWebRequest = (HttpWebRequest)WebRequest.Create(_endPointName);

httpWebRequest.ContentType = "application/x-www-form-urlencoded";
httpWebRequest.Method = "POST";
httpWebRequest.Headers["ContentType"] = "application/x-www-form-urlencoded";

System.Net.ServicePointManager.ServerCertificateValidationCallback +=
                                                  (se, cert, chain, sslerror) =>
                                                      return true;

using (var streamWriter = new StreamWriter(httpWebRequest.GetRequestStream()))
var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();

using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
                    var result = streamReader.ReadToEnd();

Distribution certificate / private key not installed

EDIT: I thought that the other computer is dead so I'm fixing my answer:

You should export the certificate from the first computer with it's private key and import it in the new computer.

I prefer the iCloud way, backup to iCloud and get it in the new computer.

If you can't do it with some reason, you can revoke the certificate in Apple developers site, then let Xcode to create a new one for you, it'll also create a fresh new private key and store it in your Keychain, just be sure to back it up in your preferred way

How do I get an animated gif to work in WPF?

I am not sure if this has been solved but the best way is to use the WpfAnimatedGid library. It is very easy, simple and straight forward to use. It only requires 2lines of XAML code and about 5 lines of C# Code in the code behind.

You will see all the necessary details of how this can be used there. This is what I also used instead of re-inventing the wheel

Bootstrap col-md-offset-* not working

<div class="jumbotron">
        <div class="container">
            <div class="row">
                    <h2 class="col-md-4 offset-md-4">Browse.</h2>
                    <h2 class="col-md-4 offset-md-4">create.</h2>
                    <h2 class="col-md-4 offset-md-4">share.</h2>

You can try this.

Convert python datetime to epoch with strftime

In Python 3.7

Return a datetime corresponding to a date_string in one of the formats emitted by date.isoformat() and datetime.isoformat(). Specifically, this function supports strings in the format(s) YYYY-MM-DD[*HH[:MM[:SS[.fff[fff]]]][+HH:MM[:SS[.ffffff]]]], where * can match any single character.

Stopping a CSS3 Animation on last frame

If you want to add this behaviour to a shorthand animation property definition, the order of sub-properties is as follows

animation-name - default none

animation-duration - default 0s

animation-timing-function - default ease

animation-delay - default 0s

animation-iteration-count - default 1

animation-direction - default normal

animation-fill-mode - you need to set this to forwards

animation-play-state - default running

Therefore in the most common case, the result will be something like this

animation: colorchange 1s ease 0s 1 normal forwards;

See the MDN documentation here

Is background-color:none valid CSS?

The answer is no.


.class {
    background-color: none; /* do not do this */


.class {
    background-color: transparent;

background-color: transparent accomplishes the same thing what you wanted to do with background-color: none.

Calling onclick on a radiobutton list using javascript

Hi, I think all of the above might work. In case what you need is simple, I used:_x000D_
    <div class="radio-buttons-choice" id="container-3-radio-buttons-choice">_x000D_
        <input type="radio" name="one" id="one-variable-equations" onclick="checkRadio(name)"><label>Only one</label><br>_x000D_
        <input type="radio" name="multiple" id="multiple-variable-equations" onclick="checkRadio(name)"><label>I have multiple</label>_x000D_
function checkRadio(name) {_x000D_
    if(name == "one"){_x000D_
    console.log("Choice: ", name);_x000D_
        document.getElementById("one-variable-equations").checked = true;_x000D_
        document.getElementById("multiple-variable-equations").checked = false;_x000D_
    } else if (name == "multiple"){_x000D_
        console.log("Choice: ", name);_x000D_
        document.getElementById("multiple-variable-equations").checked = true;_x000D_
        document.getElementById("one-variable-equations").checked = false;_x000D_

TypeError: got multiple values for argument

I was brought here for a reason not explicitly mentioned in the answers so far, so to save others the trouble:

The error also occurs if the function arguments have changed order - for the same reason as in the accepted answer: the positional arguments clash with the keyword arguments.

In my case it was because the argument order of the Pandas set_axis function changed between 0.20 and 0.22:

0.20: DataFrame.set_axis(axis, labels)
0.22: DataFrame.set_axis(labels, axis=0, inplace=None)

Using the commonly found examples for set_axis results in this confusing error, since when you call:

df.set_axis(['a', 'b', 'c'], axis=1)

prior to 0.22, ['a', 'b', 'c'] is assigned to axis because it's the first argument, and then the positional argument provides "multiple values".

Adding up BigDecimals using Streams

If you don't mind a third party dependency, there is a class named Collectors2 in Eclipse Collections which contains methods returning Collectors for summing and summarizing BigDecimal and BigInteger. These methods take a Function as a parameter so you can extract a BigDecimal or BigInteger value from an object.

List<BigDecimal> list = mList(

BigDecimal sum = -> e));
Assert.assertEquals(BigDecimal.valueOf(3.4), sum);

BigDecimalSummaryStatistics statistics = -> e));
Assert.assertEquals(BigDecimal.valueOf(3.4), statistics.getSum());
Assert.assertEquals(BigDecimal.valueOf(0.1), statistics.getMin());
Assert.assertEquals(BigDecimal.valueOf(2.1), statistics.getMax());
Assert.assertEquals(BigDecimal.valueOf(0.85), statistics.getAverage());

Note: I am a committer for Eclipse Collections.

Possible to make labels appear when hovering over a point in matplotlib?

A slight edit on an example provided in

import numpy as np
import matplotlib.pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)
ax.set_title('click on points')

line, = ax.plot(np.random.rand(100), '-', picker=5)  # 5 points tolerance

def onpick(event):
    thisline = event.artist
    xdata = thisline.get_xdata()
    ydata = thisline.get_ydata()
    ind = event.ind
    print('onpick points:', *zip(xdata[ind], ydata[ind]))

fig.canvas.mpl_connect('pick_event', onpick)

This plots a straight line plot, as Sohaib was asking

postgresql - replace all instances of a string within text field

Here is an example that replaces all instances of 1 or more white space characters in a column with an underscore using regular expression -

select distinct on (pd)
regexp_replace(rndc.pd, '\\s+', '_','g') as pd
from rndc14_ndc_mstr rndc;

Can I set an unlimited length for maxJsonLength in web.config?

You can configure the max length for json requests in your web.config file:

                <jsonSerialization maxJsonLength="....">

The default value for maxJsonLength is 102400. For more details, see this MSDN page:

What is the "__v" field in Mongoose

It is the version key.It gets updated whenever a new update is made. I personally don't like to disable it .

Read this solution if you want to know more [1]: Mongoose versioning: when is it safe to disable it?

How to sort an STL vector?

Overload less than operator, then sort. This is an example I found off the web...

class MyData
  int m_iData;
  string m_strSomeOtherData;
  bool operator<(const MyData &rhs) const { return m_iData < rhs.m_iData; }

std::sort(myvector.begin(), myvector.end());

Source: here

Hiding and Showing TabPages in tabControl

I've been using the same approach of saving the hidden TabPages in a private list, but the problem is that when I want to show the TabPage again, they doesn't appears in the original position (order). So, finally, I wrote a class in VB to add the TabControl with two methods: HideTabPageByName and ShowTabPageByName. You can just call the methods passing the name (not the TabPage instance).

Public Class CS_Control_TabControl
    Inherits System.Windows.Forms.TabControl

    Private mTabPagesHidden As New Dictionary(Of String, System.Windows.Forms.TabPage)
    Private mTabPagesOrder As List(Of String)

    Public Sub HideTabPageByName(ByVal TabPageName As String)
        If mTabPagesOrder Is Nothing Then
            ' The first time the Hide method is called, save the original order of the TabPages
            mTabPagesOrder = New List(Of String)
            For Each TabPageCurrent As TabPage In Me.TabPages
        End If

        If Me.TabPages.ContainsKey(TabPageName) Then
            Dim TabPageToHide As TabPage

            ' Get the TabPage object
            TabPageToHide = TabPages(TabPageName)
            ' Add the TabPage to the internal List
            mTabPagesHidden.Add(TabPageName, TabPageToHide)
            ' Remove the TabPage from the TabPages collection of the TabControl
        End If
    End Sub

    Public Sub ShowTabPageByName(ByVal TabPageName As String)
        If mTabPagesHidden.ContainsKey(TabPageName) Then
            Dim TabPageToShow As TabPage

            ' Get the TabPage object
            TabPageToShow = mTabPagesHidden(TabPageName)
            ' Add the TabPage to the TabPages collection of the TabControl
            Me.TabPages.Insert(GetTabPageInsertionPoint(TabPageName), TabPageToShow)
            ' Remove the TabPage from the internal List
        End If
    End Sub

    Private Function GetTabPageInsertionPoint(ByVal TabPageName As String) As Integer
        Dim TabPageIndex As Integer
        Dim TabPageCurrent As TabPage
        Dim TabNameIndex As Integer
        Dim TabNameCurrent As String

        For TabPageIndex = 0 To Me.TabPages.Count - 1
            TabPageCurrent = Me.TabPages(TabPageIndex)
            For TabNameIndex = TabPageIndex To mTabPagesOrder.Count - 1
                TabNameCurrent = mTabPagesOrder(TabNameIndex)
                If TabNameCurrent = TabPageCurrent.Name Then
                    Exit For
                End If
                If TabNameCurrent = TabPageName Then
                    Return TabPageIndex
                End If
        Return TabPageIndex
    End Function

    Protected Overrides Sub Finalize()
        mTabPagesHidden = Nothing
        mTabPagesOrder = Nothing
    End Sub
End Class

PHP, MySQL error: Column count doesn't match value count at row 1

The number of column parameters in your insert query is 9, but you've only provided 8 values.

INSERT INTO dbname (id, Name, Description, shortDescription, Ingredients, Method, Length, dateAdded, Username) VALUES ('', '%s', '%s', '%s', '%s', '%s', '%s', '%s')

The query should omit the "id" parameter, because it is auto-generated (or should be anyway):

INSERT INTO dbname (Name, Description, shortDescription, Ingredients, Method, Length, dateAdded, Username) VALUES ('', '%s', '%s', '%s', '%s', '%s', '%s', '%s')

Python unittest - opposite of assertRaises?

I am the original poster and I accepted the above answer by DGH without having first used it in the code.

Once I did use I realised that it needed a little tweaking to actually do what I needed it to do (to be fair to DGH he/she did say "or something similar" !).

I thought it was worth posting the tweak here for the benefit of others:

        a = Application("abcdef", "")
    except pySourceAidExceptions.PathIsNotAValidOne:

What I was attempting to do here was to ensure that if an attempt was made to instantiate an Application object with a second argument of spaces the pySourceAidExceptions.PathIsNotAValidOne would be raised.

I believe that using the above code (based heavily on DGH's answer) will do that.

Create a new RGB OpenCV image using Python?

The new cv2 interface for Python integrates numpy arrays into the OpenCV framework, which makes operations much simpler as they are represented with simple multidimensional arrays. For example, your question would be answered with:

import cv2  # Not actually necessary if you just want to create an image.
import numpy as np
blank_image = np.zeros((height,width,3), np.uint8)

This initialises an RGB-image that is just black. Now, for example, if you wanted to set the left half of the image to blue and the right half to green , you could do so easily:

blank_image[:,0:width//2] = (255,0,0)      # (B, G, R)
blank_image[:,width//2:width] = (0,255,0)

If you want to save yourself a lot of trouble in future, as well as having to ask questions such as this one, I would strongly recommend using the cv2 interface rather than the older cv one. I made the change recently and have never looked back. You can read more about cv2 at the OpenCV Change Logs.

Illegal Character when trying to compile java code

That's a byte order mark, as everyone says.

javac does not understand the BOM, not even when you try something like

javac -encoding UTF8

You need to strip the BOM or convert your source file to another encoding. Notepad++ can convert a single files encoding, I'm not aware of a batch utility on the Windows platform for this.

The java compiler will assume the file is in your platform default encoding, so if you use this, you don't have to specify the encoding.

How to view UTF-8 Characters in VIM or Gvim

Is this problem solved meanwhile?

I had the problem that gvim didn't display all unicode characters (but only a subset, including the umlauts and accented characters), while :set guifont? was empty; see my question. After reading here, setting the guifont to a sensible value fixed it for me. However, I don't need characters beyond 2 bytes.

How to take a first character from the string

Try this:

Dim s = "RAJAN"
Dim firstChar = s(0)

You can even do this:

Dim firstChar = "RAJAN"(0)

Java, How to add library files in netbeans?

In Netbeans 8.2

1. Dowload the binaries from the web source. The Apache Commos are in: [][1] In this case, you must select the "Logging" in the Components menu and follow the link to downloads in the Releases part. Direct URL: [][2] For me, the correct download was the file: from the Binaries.

2. Unzip downloaded content. Now, you can see several jar files inside the directory created from the zip file.

3. Add the library to the project. Right click in the project, select Properties and click in Libraries (in the left side). Click the button "Add Jar/Folder". Go to the previously unzipped contents and select the properly jar file. Clic in "Open" and click in"Ok". The library has been loaded!

converting date time to 24 hour format

import java.text.SimpleDateFormat;

import java.util.Date;

public class DateFormatExample {

public static void main(String args[]) {

    // This is how to get today's date in Java
    Date today = new Date();

    //If you print Date, you will get un formatted output
    System.out.println("Today is : " + today);

    //formatting date in Java using SimpleDateFormat
    SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("dd-MM-yyyy");
    String date = DATE_FORMAT.format(today);
    System.out.println("Today in dd-MM-yyyy format : " + date);

    //Another Example of formatting Date in Java using SimpleDateFormat
    DATE_FORMAT = new SimpleDateFormat("dd/MM/yy");
    date = DATE_FORMAT.format(today);
    System.out.println("Today in dd/MM/yy pattern : " + date);

    //formatting Date with time information
    DATE_FORMAT = new SimpleDateFormat("dd-MM-yy:HH:mm:SS");
    date = DATE_FORMAT.format(today);
    System.out.println("Today in dd-MM-yy:HH:mm:SS : " + date);

    //SimpleDateFormat example - Date with timezone information
    DATE_FORMAT = new SimpleDateFormat("dd-MM-yy:HH:mm:SS Z");
    date = DATE_FORMAT.format(today);
    System.out.println("Today in dd-MM-yy:HH:mm:SSZ : " + date);




Today is : Fri Nov 02 16:11:27 IST 2012

Today in dd-MM-yyyy format : 02-11-2012

Today in dd/MM/yy pattern : 02/11/12

Today in dd-MM-yy:HH:mm:SS : 02-11-12:16:11:316

Today in dd-MM-yy:HH:mm:SSZ : 02-11-12:16:11:316 +0530

Float sum with javascript

Once you read what What Every Computer Scientist Should Know About Floating-Point Arithmetic you could use the .toFixed() function:

var result = parseFloat('2.3') + parseFloat('2.4');

Label encoding across multiple columns in scikit-learn

We don't need a LabelEncoder.

You can convert the columns to categoricals and then get their codes. I used a dictionary comprehension below to apply this process to every column and wrap the result back into a dataframe of the same shape with identical indices and column names.

>>> pd.DataFrame({col: df[col].astype('category') for col in df}, index=df.index)
   location  owner  pets
0         1      1     0
1         0      2     1
2         0      0     0
3         1      1     2
4         1      3     1
5         0      2     1

To create a mapping dictionary, you can just enumerate the categories using a dictionary comprehension:

>>> {col: {n: cat for n, cat in enumerate(df[col].astype('category').cat.categories)} 
     for col in df}

{'location': {0: 'New_York', 1: 'San_Diego'},
 'owner': {0: 'Brick', 1: 'Champ', 2: 'Ron', 3: 'Veronica'},
 'pets': {0: 'cat', 1: 'dog', 2: 'monkey'}}

How to solve error "Missing `secret_key_base` for 'production' environment" (Rails 4.1)

Demi Magus answer worked for me until Rails 5.

On Apache2/Passenger/Ruby (2.4)/Rails (5.1.6), I had to put


from Demi Magus answer in /etc/apache2/envvars, cause /etc/profile seems to be ignored.


Insert HTML with React Variable Statements (JSX)

If anyone else still lands here. With ES6 you can create your html variable like so:

    var thisIsMyCopy = (
        <p>copy copy copy <strong>strong copy</strong></p>

How to Code Double Quotes via HTML Codes

There is no difference, in browsers that you can find in the wild these days (that is, excluding things like Netscape 1 that you might find in a museum). There is no reason to suspect that any of them would be deprecated ever, especially since they are all valid in XML, in HTML 4.01, and in HTML5 CR.

There is no reason to use any of them, as opposite to using the Ascii quotation mark (") directly, except in the very special case where you have an attribute value enclosed in such marks and you would like to use the mark inside the value (e.g., title="Hello &quot;world&quot;"), and even then, there are almost always better options (like title='Hello "word"' or title="Hello “word”".

If you want to use “smart” quotation marks instead, then it’s a different question, and none of the constructs has anything to do with them. Some people expect notations like &quot; to produce “smart” quotes, but it is easy to see that they don’t; the notations unambiguously denote the Ascii quote ("), as used in computer languages.

How can I force component to re-render with hooks in React?

Simple code

const forceUpdate = React.useReducer(bool => !bool)[1];



Targeting .NET Framework 4.5 via Visual Studio 2010

FYI, if you want to create an Installer package in VS2010, unfortunately it only targets .NET 4. To work around this, you have to add NET 4.5 as a launch condition.

Add the following in to the Launch Conditions of the installer (Right click, View, Launch Conditions).

In "Search Target Machine", right click and select "Add Registry Search".

RegKey: Software\Microsoft\NET Framework Setup\NDP\v4\Full
Root: vsdrrHKLM
Value: Release

Add new "Launch Condition":

Condition: REGISTRYVALUE1>="#378389"
Message: Setup requires .NET Framework 4.5 to be installed.


378389 = .NET Framework 4.5

378675 = .NET Framework 4.5.1 installed with Windows 8.1

378758 = .NET Framework 4.5.1 installed on Windows 8, Windows 7 SP1, or Windows Vista SP2

379893 = .NET Framework 4.5.2

Launch condition reference:

Getting list of items inside div using Selenium Webdriver

alternatively, you can try writing a specific element:

    //label[1] is the first element.
    el =  await driver.findElement(By.xpath("//div[@class=\"facetContainerDiv\"]/div/label[1]/input")));

More information can be found here:

What is the difference between "word-break: break-all" versus "word-wrap: break-word" in CSS

word-wrap: break-word recently changed to overflow-wrap: break-word

  • will wrap long words onto the next line.
  • adjusts different words so that they do not break in the middle.

word-break: break-all

  • irrespective of whether it’s a continuous word or many words, breaks them up at the edge of the width limit. (i.e. even within the characters of the same word)

So if you have many fixed-size spans which get content dynamically, you might just prefer using word-wrap: break-word, as that way only the continuous words are broken in between, and in case it’s a sentence comprising many words, the spaces are adjusted to get intact words (no break within a word).

And if it doesn’t matter, go for either.

MongoDB Show all contents from all collections

This will do:

db.getCollectionNames().forEach(c => {
    db[c].find().forEach(d => {

Handling NULL values in Hive

Try to include length > 0 as well.

column1 is not NULL AND column1 <> '' AND length(column1) > 0 

What is the simplest way to convert a Java string from all caps (words separated by underscores) to CamelCase (no word separators)?

protected String toCamelCase(String input) {
    if (input == null) {
        return null;

    if (input.length() == 0) {
        return "";

    // lowercase the first character
    String camelCaseStr = input.substring(0, 1).toLowerCase();

    if (input.length() > 1) {
        boolean isStartOfWord = false;

        for (int i = 1; i < input.length(); i++) {
            char currChar = input.charAt(i);
            if (currChar == '_') {
                // new word. ignore underscore
                isStartOfWord = true;
            } else if (Character.isUpperCase(currChar)) {
                // capital letter. if start of word, keep it
                if (isStartOfWord) {
                    camelCaseStr += currChar;
                } else {
                    camelCaseStr += Character.toLowerCase(currChar);
                isStartOfWord = false;
            } else {
                camelCaseStr += currChar;
                isStartOfWord = false;

    return camelCaseStr;

How can I truncate a string to the first 20 words in PHP?

use PHP tokenizer function strtok() in a loop.

$token = strtok($string, " "); // we assume that words are separated by sapce or tab
$i = 0;
$first20Words = '';
while ($token !== false && $i < 20) {
    $first20Words .= $token;
    $token = strtok(" ");
echo $first20Words;

Compiling a java program into an executable

I use launch4j

ANT Command:

<target name="jar" depends="compile, buildDLLs, copy">
    <jar basedir="${java.bin.dir}" destfile="${build.dir}/Project.jar" manifest="META-INF/MANIFEST.MF" />

<target name="exe" depends="jar">
    <exec executable="cmd" dir="${launch4j.home}">
        <arg line="/c launch4jc.exe ${basedir}/${launch4j.dir}/L4J_ProjectConfig.xml" />

How to call Stored Procedure in Entity Framework 6 (Code-First)?

Take a look to this link that shows how works the mapping of EF 6 with Stored Procedures to make an Insert, Update and Delete:


Here is a great example to call a stored procedure from Code First:

Lets say you have to execute an Stored Procedure with a single parameter, and that Stored Procedure returns a set of data that match with the Entity States, so we will have this:

var countryIso = "AR"; //Argentina

var statesFromArgentina = context.Countries.SqlQuery(
                                      "dbo.GetStatesFromCountry @p0", countryIso

Now lets say that we whant to execute another stored procedure with two parameters:

var countryIso = "AR"; //Argentina
var stateIso = "RN"; //Río Negro

var citiesFromRioNegro = context.States.SqlQuery(
                            "dbo.GetCitiesFromState @p0, @p1", countryIso, stateIso

Notice that we are using index-based naming for parameters. This is because Entity Framework will wrap these parameters up as DbParameter objects fro you to avoid any SQL injection issues.

Hope this example helps!

How to calculate number of days between two dates

Try this Using moment.js (Its quite easy to compute date operations in javascript)

firstDate.diff(secondDate, 'days', false);// true|false for fraction value

Result will give you number of days in integer.

Get a Windows Forms control by name in C#

string name = "the_name_you_know";

Control ctn = this.Controls[name];

ctn.Text = "Example...";

Simulate string split function in Excel formula

Some great worksheet-fu in the other answers but I think they've overlooked that you can define a user-defined function (udf) and call this from the sheet or a formula.

The next problem you have is to decide either to work with a whole array or with element.

For example this UDF function code

Public Function UdfSplit(ByVal sText As String, Optional ByVal sDelimiter As String = " ", Optional ByVal lIndex As Long = -1) As Variant
    Dim vSplit As Variant
    vSplit = VBA.Split(sText, sDelimiter)
    If lIndex > -1 Then
        UdfSplit = vSplit(lIndex)
        UdfSplit = vSplit
    End If
End Function

allows single elements with the following in one cell


or one can use a blocks of cells with


React Js conditionally applying class attributes

Reference to @split fire answer, we can update it with template literals, which is more readable,For reference Checkout javascript template literal

<div className={`btn-group pull-right ${this.props.showBulkActions ? 'show' : 'hidden'}`}>

Can CSS force a line break after each word in an element?

If you want to be able to choose from different solutions, in addition to the given answers...

An alternative method is to give the container a width of 0 and to make sure overflow is visible. Then each word will overflow out of it and will be on its own line.

div {_x000D_
  width: 0;_x000D_
  overflow: visible;_x000D_
<div>Short Word</div>_x000D_
<div>Gargantuan Word</div>

Or you can use one of those newly proposed width values, provided those still exist by the time you read this.

div {_x000D_
  width: min-intrinsic;       /* old Chrome, Safari */_x000D_
  width: -webkit-min-content; /* less old Chrome, Safari */_x000D_
  width: -moz-min-content;    /* current Firefox */_x000D_
  width: min-content;         /* current Chrome, Safari; not IE or Edge */_x000D_
<div>Short Word</div>_x000D_
<div>Gargantuan Word</div>

CSS "color" vs. "font-color"

I know this is an old post but as MisterZimbu stated, the color property is defining the values of other properties, as the border-color and, with CSS3, of currentColor.

currentColor is very handy if you want to use the font color for other elements (as the background or custom checkboxes and radios of inner elements for example).


.element {_x000D_
  color: green;_x000D_
  background: red;_x000D_
  display: block;_x000D_
  width: 200px;_x000D_
  height: 200px;_x000D_
  padding: 0;_x000D_
  margin: 0;_x000D_
.innerElement1 {_x000D_
  border: solid 10px;_x000D_
  display: inline-block;_x000D_
  width: 60px;_x000D_
  height: 100px;_x000D_
  margin: 10px;_x000D_
.innerElement2 {_x000D_
  background: currentColor;_x000D_
  display: inline-block;_x000D_
  width: 60px;_x000D_
  height: 100px;_x000D_
  margin: 10px;_x000D_
<div class="element">_x000D_
  <div class="innerElement1"></div>_x000D_
  <div class="innerElement2"></div>_x000D_

Is there a null-coalescing (Elvis) operator or safe navigation operator in javascript?

This was an interesting solution for the safe navigation operator using some mixin..

  // Assume you have the following data structure
  var companies = {
      orbeon: {
          cfo: "Erik",
          cto: "Alex"

  // Extend Underscore.js
      // Safe navigation
      attr: function(obj, name) { return obj == null ? obj : obj[name]; },
      // So we can chain console.log
      log: function(obj) { console.log(obj); }

  // Shortcut, 'cause I'm lazy
  var C = _(companies).chain();

  // Simple case: returns Erik
  // Simple case too, no CEO in Orbeon, returns undefined
  // IBM unknown, but doesn't lead to an error, returns undefined

Convert alphabet letters to number in Python

>>> [str(ord(string.lower(c)) - ord('a') + 1) for c in string.letters]
['1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17',
'18', '19', '20', '21', '22', '23', '24', '25', '26', '1', '2', '3', '4', '5', '6', '7', '8',
'9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19', '20', '21', '22', '23', '24',
 '25', '26']

How to read a line from a text file in c/c++?

In C, fgets(), and you need to know the maximum size to prevent truncation.

How to sort List of objects by some property

public class ActiveAlarm implements Comparable<ActiveAlarm> {
    public long timeStarted;
    public long timeEnded;
    private String name = "";
    private String description = "";
    private String event;
    private boolean live = false;

    public int compareTo(ActiveAlarm a) {
        if ( this.timeStarted > a.timeStarted )
            return 1;
        else if ( this.timeStarted < a.timeStarted )
            return -1;
        else {
             if ( this.timeEnded > a.timeEnded )
                 return 1;
                 return -1;

That should give you a rough idea. Once that's done, you can call Collections.sort() on the list.

Synchronizing a local Git repository with a remote one

If you are talking about syncing a forked repo then you can follow these steps.

How to sync a fork repository from git

  1. check your current git branch

    git branch

  2. checkout to master if you are not on master

    git checkout master

  3. Fetch the upstream repository if you have correct access rights

    git fetch upstream

  4. If you are getting below error then run

    git remote add upstream [email protected]:upstream_clone_repo_url/xyz.git

    fatal: 'upstream/master' does not appear to be a git repository  
    fatal: Could not read from remote repository.
    Please make sure you have the correct access rights and the repository exists.
  5. Now run the below command.

    git fetch upstream

  6. Now if you are on master then merge the upstream/master into master branch

    git merge upstream/master

    That's it!!

    Crosscheck via git remote command, more specific git remote -v

    If I also have commit rights to the upstream repo, I can create a local upstream branch and do work that will go upstream there.

How to get disk capacity and free space of remote computer

Much simpler solution:

Get-PSDrive C | Select-Object Used,Free

and for remote computers (needs Powershell Remoting)

Invoke-Command -ComputerName SRV2 {Get-PSDrive C} | Select-Object PSComputerName,Used,Free

What's the -practical- difference between a Bare and non-Bare repository?

$ git help repository-layout

A Git repository comes in two different flavours:

  • a .git directory at the root of the working tree;
  • a .git directory that is a bare repository (i.e. without its own working tree), that is typically used for exchanging histories with others by pushing into it and fetching from it.

How to add leading zeros?

Here is another alternative for adding leading to 0s to strings such as CUSIPs which can sometimes look like a number and which many applications such as Excel will corrupt and remove the leading 0s or convert them to scientific notation.

When I tried the answer provided by @metasequoia the vector returned had leading spaces and not 0s. This was the same problem mentioned by @user1816679 -- and removing the quotes around the 0 or changing from %d to %s did not make a difference either. FYI, I am using RStudio Server running on an Ubuntu Server. This little two-step solution worked for me:

gsub(pattern = " ", replacement = "0", x = sprintf(fmt = "%09s", ids[,CUSIP]))

using the %>% pipe function from the magrittr package it could look like this:

sprintf(fmt = "%09s", ids[,CUSIP]) %>% gsub(pattern = " ", replacement = "0", x = .)

I'd prefer a one-function solution, but it works.

How to get the public IP address of a user in C#

just use this..................

public string GetIP()
   string externalIP = "";
   externalIP = (new WebClient()).DownloadString("");
   externalIP = (new Regex(@"\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}")).Matches(externalIP)[0].ToString();
   return externalIP;

CSS disable hover effect

From your question all I can understand is that you already have some hover effect on your button which you want remove. For that either remove that css which causes the hover effect or override it.

For overriding, do this

    //overriding css goes here

For example if your button's background color changes on hover from red to blue. In the overriding css you will make it as red so that it doesnt change.

Also go through all the rules of writing and overriding css. Get familiar with what css will have what priority.

Best of luck.

Warning comparison between pointer and integer

It should be

if (*message == '\0')

In C, simple quotes delimit a single character whereas double quotes are for strings.

Sort an ArrayList based on an object field

Modify the DataNode class so that it implements Comparable interface.

public int compareTo(DataNode o)
     return(degree -;

then just use


json_encode sparse PHP array as JSON array, not JSON object

Array in JSON are indexed array only, so the structure you're trying to get is not valid Json/Javascript.

PHP Associatives array are objects in JSON, so unless you don't need the index, you can't do such conversions.

If you want to get such structure you can do:

$indexedOnly = array();

foreach ($associative as $row) {
    $indexedOnly[] = array_values($row);


Will returns something like:

     [0, "name1", "n1"],
     [1, "name2", "n2"],

Differences between JDK and Java SDK

I think jdk has certain features which can be used along with particular framework. Well call it SDK as a whole.

Like Android or Blackberry both use java along with their framework.

Javascript: 'window' is not defined

Trying to access an undefined variable will throw you a ReferenceError.

A solution to this is to use typeof:

if (typeof window === "undefined") {
  console.log("Oops, `window` is not defined")

or a try catch:

try { window } catch (err) {
  console.log("Oops, `window` is not defined")

While typeof window is probably the cleanest of the two, the try catch can still be useful in some cases.

When does a process get SIGABRT (signal 6)?

In my case, it was due to an input in an array at an index equal to the length of the array.

string x[5];

for(int i=1; i<=5; i++){



x[5] is being accessed which is not present.

Python Matplotlib figure title overlaps axes label when using twiny

I'm not sure whether it is a new feature in later versions of matplotlib, but at least for 1.3.1, this is simply:

plt.title(figure_title, y=1.08)

This also works for plt.suptitle(), but not (yet) for plt.xlabel(), etc.

How can I debug a HTTP POST in Chrome?

It has a tricky situation: If you submit a post form, then Chrome will open a new tab to send the request. It's right until now, but if it triggers an event to download file(s), this tab will close immediately so that you cannot capture this request in the Dev Tool.

Solution: Before submitting the post form, you need to cut off your network, which makes the request cannot send successfully so that the tab will not be closed. And then you can capture the request message in the Chrome Devtool(Refreshing the new tab if necessary)

Java - removing first character of a string

Another solution, you can solve your problem using replaceAll with some regex ^.{1} (regex demo) for example :

String str = "Jamaica";
int nbr = 1;
str = str.replaceAll("^.{" + nbr + "}", "");//Output = amaica

get keys of json-object in JavaScript

[What you have is just an object, not a "json-object". JSON is a textual notation. What you've quoted is JavaScript code using an array initializer and an object initializer (aka, "object literal syntax").]

If you can rely on having ECMAScript5 features available, you can use the Object.keys function to get an array of the keys (property names) in an object. All modern browsers have Object.keys (including IE9+).

Object.keys(jsonData).forEach(function(key) {
    var value = jsonData[key];
    // ...

The rest of this answer was written in 2011. In today's world, A) You don't need to polyfill this unless you need to support IE8 or earlier (!), and B) If you did, you wouldn't do it with a one-off you wrote yourself or grabbed from an SO answer (and probably shouldn't have in 2011, either). You'd use a curated polyfill, possibly from es5-shim or via a transpiler like Babel that can be configured to include polyfills (which may come from es5-shim).

Here's the rest of the answer from 2011:

Note that older browsers won't have it. If not, this is one of the ones you can supply yourself:

if (typeof Object.keys !== "function") {
    (function() {
        var hasOwn = Object.prototype.hasOwnProperty;
        Object.keys = Object_keys;
        function Object_keys(obj) {
            var keys = [], name;
            for (name in obj) {
                if (, name)) {
            return keys;

That uses a loop (more info here) to loop through all of the property names the object has, and uses Object.prototype.hasOwnProperty to check that the property is owned directly by the object rather than being inherited.

(I could have done it without the self-executing function, but I prefer my functions to have names, and to be compatible with IE you can't use named function expressions [well, not without great care]. So the self-executing function is there to avoid having the function declaration create a global symbol.)

How to get character for a given ascii value

Do you mean "A" (a string) or 'A' (a char)?

int unicode = 65;
char character = (char) unicode;
string text = character.ToString();

Note that I've referred to Unicode rather than ASCII as that's C#'s native character encoding; essentially each char is a UTF-16 code point.

Python basics printing 1 to 100

x=1 while x<=100: print(x) x=x+3

Remove all occurrences of char from string

Evaluation of main answers with a performance benchmark which confirms concerns that the current chosen answer makes costly regex operations under the hood

To date the provided answers come in 3 main styles (ignoring the JavaScript answer ;) ):

  • Use String.replace(charsToDelete, ""); which uses regex under the hood
  • Use Lambda
  • Use simple Java implementation

In terms of code size clearly the String.replace is the most terse. The simple Java implementation is slightly smaller and cleaner (IMHO) than the Lambda (don't get me wrong - I use Lambdas often where they are appropriate)

Execution speed was, in order of fastest to slowest: simple Java implementation, Lambda and then String.replace() (that invokes regex).

By far the fastest implementation was the simple Java implementation tuned so that it preallocates the StringBuilder buffer to the max possible result length and then simply appends chars to the buffer that are not in the "chars to delete" string. This avoids any reallocates that would occur for Strings > 16 chars in length (the default allocation for StringBuilder) and it avoids the "slide left" performance hit of deleting characters from a copy of the string that occurs is the Lambda implementation.

The code below runs a simple benchmark test, running each implementation 1,000,000 times and logs the elapsed time.

The exact results vary with each run but the order of performance never changes:

Start simple Java implementation
Time: 157 ms
Start Lambda implementation
Time: 253 ms
Start String.replace implementation
Time: 634 ms

The Lambda implementation (as copied from Kaplan's answer) may be slower because it performs a "shift left by one" of all characters to the right of the character being deleted. This would obviously get worse for longer strings with lots of characters requiring deletion. Also there might be some overhead in the Lambda implementation itself.

The String.replace implementation, uses regex and does a regex "compile" at each call. An optimization of this would be to use regex directly and cache the compiled pattern to avoid the cost of compiling it each time.

package com.sample;

import java.util.function.BiFunction;

public class Main {

    static public String deleteCharsSimple(String fromString, String charsToDelete)
        StringBuilder buf = new StringBuilder(fromString.length()); // Preallocate to max possible result length
        for(int i = 0; i < fromString.length(); i++)
            if (charsToDelete.indexOf(fromString.charAt(i)) < 0)
                buf.append(fromString.charAt(i));   // char not in chars to delete so add it
        return buf.toString();

    static public String deleteCharsLambda(String fromString1, String charsToDelete)
        BiFunction<String, String, String> deleteChars = (fromString, chars) -> {
            StringBuilder buf = new StringBuilder(fromString);
            IntStream.range(0, buf.length()).forEach(i -> {
                while (i < buf.length() && chars.indexOf(buf.charAt(i)) >= 0)
            return (buf.toString());

        return deleteChars.apply(fromString1, charsToDelete);

    static public String deleteCharsReplace(String fromString, String charsToDelete)
        return fromString.replace(charsToDelete, "");

    public static void main(String[] args)
        String str = "XXXTextX XXto modifyX";
        String charsToDelete = "X";  // Should only be one char as per OP's requirement

        long start, end;

        System.out.println("Start simple");
        start = System.currentTimeMillis();

        for (int i = 0; i < 1000000; i++)
            deleteCharsSimple(str, charsToDelete);

        end = System.currentTimeMillis();
        System.out.println("Time: " + (end - start));

        System.out.println("Start lambda");
        start = System.currentTimeMillis();
        for (int i = 0; i < 1000000; i++)
            deleteCharsLambda(str, charsToDelete);

        end = System.currentTimeMillis();
        System.out.println("Time: " + (end - start));

        System.out.println("Start replace");
        start = System.currentTimeMillis();

        for (int i = 0; i < 1000000; i++)
            deleteCharsReplace(str, charsToDelete);

        end = System.currentTimeMillis();
        System.out.println("Time: " + (end - start));

Change label text using JavaScript

Because the script will get executed first.. When the script will get executed, at that time controls are not getting loaded. So after loading controls you write a script.

It will work.

How to check Oracle patches are installed?

I understand the original post is for Oracle 10 but this is for reference by anyone else who finds it via Google.

Under Oracle 12c, I found that that my registry$history is empty. This works instead:

select * from registry$sqlpatch;

How to install Python packages from the tar.gz file without using pip install

Is it possible for you to use sudo apt-get install python-seaborn instead? Basically tar.gz is just a zip file containing a setup, so what you want to do is to unzip it, cd to the place where it is downloaded and use gunzip -c seaborn-0.7.0.tar.gz | tar xf - for linux. Change dictionary into the new seaborn unzipped file and execute python install

Parse large JSON file in Nodejs

Just as I was thinking that it would be fun to write a streaming JSON parser, I also thought that maybe I should do a quick search to see if there's one already available.

Turns out there is.

Since I just found it, I've obviously not used it, so I can't comment on its quality, but I'll be interested to hear if it works.

It does work consider the following Javascript and _.isString:

  .on('data', (d) => {
    console.log(typeof d);
    console.log("isString: " + _.isString(d))

This will log objects as they come in if the stream is an array of objects. Therefore the only thing being buffered is one object at a time.

Module not found: Error: Can't resolve 'core-js/es6'

After Migrated to Angular8, core-js/es6 or core-js/es7 Will not work.

You have to simply replace import core-js/es/

For ex.

import 'core-js/es6/symbol'  


import 'core-js/es/symbol'

This will work properly.

Calculate Age in MySQL (InnoDb)

You can use TIMESTAMPDIFF(unit, datetime_expr1, datetime_expr2) function:



Syntax error near unexpected token 'fi'

The first problem with your script is that you have to put a space after the [.
Type type [ to see what is really happening. It should tell you that [ is an alias to test command, so [ ] in bash is not some special syntax for conditionals, it is just a command on its own. What you should prefer in bash is [[ ]]. This common pitfall is greatly explained here and here.

Another problem is that you didn't quote "$f" which might become a problem later. This is explained here

You can use arithmetic expressions in if, so you don't have to use [ ] or [[ ]] at all in some cases. More info here

Also there's no need to use \n in every echo, because echo places newlines by default. If you want TWO newlines to appear, then use echo -e 'start\n' or echo $'start\n' . This $'' syntax is explained here

To make it completely perfect you should place -- before arbitrary filenames, otherwise rm might treat it as a parameter if the file name starts with dashes. This is explained here.

So here's your script:

echo "start"
for f in *.jpg
    echo "fname is $fname"
    if (( fname % 2 == 1 )); then
        echo "removing $fname"
        rm -- "$f"

Can Mysql Split a column?


substring_index(`column`,',',1) ==> first value
substring_index(substring_index(`column`,',',-2),',',1)=> second value
substring_index(substring_index(`column`,',',-1),',',1)=> third value

in your where clause.

SELECT * FROM `table`

What does .shape[] do in "for i in range(Y.shape[0])"?

shape is a tuple that gives dimensions of the array..

>>> c = arange(20).reshape(5,4)
>>> c
array([[ 0,  1,  2,  3],
       [ 4,  5,  6,  7],
       [ 8,  9, 10, 11],
       [12, 13, 14, 15],
       [16, 17, 18, 19]])


Gives the number of rows


Gives number of columns

How to save the output of a console.log(object) to a file?

Right click on object and saving was not available for me.

The working solution for me is given below

Log as pretty string shown in this answer

console.log('jsonListBeauty', JSON.stringify(jsonList, null, 2));

in Chrome DevTools, Log shows as below


Just press Copy, It will be copied to clipboard with desired spacing level

Paste it on your favorite text editor and save it

image took on 15/02/2021, Google Chrome Version 88.0.4324.150

How to replace plain URLs with links?

Replacing URLs with links (Answer to the General Problem)

The regular expression in the question misses a lot of edge cases. When detecting URLs, it's always better to use a specialized library that handles international domain names, new TLDs like .museum, parentheses and other punctuation within and at the end of the URL, and many other edge cases. See the Jeff Atwood's blog post The Problem With URLs for an explanation of some of the other issues.

The best summary of URL matching libraries is in Dan Dascalescu's Answer +100
(as of Feb 2014)

"Make a regular expression replace more than one match" (Answer to the specific problem)

Add a "g" to the end of the regular expression to enable global matching:


But that only fixes the problem in the question where the regular expression was only replacing the first match. Do not use that code.

What is the Python 3 equivalent of "python -m SimpleHTTPServer"

The equivalent is:

python3 -m http.server

Moment JS - check if a date is today or in the future

Use the simplest one to check for future date

if(moment().diff(yourDate) >=  0)
     alert ("Past or current date");
     alert("It is a future date");

How do you check whether a number is divisible by another number (Python)?

You do this using the modulus operator, %

n % k == 0

evaluates true if and only if n is an exact multiple of k. In elementary maths this is known as the remainder from a division.

In your current approach you perform a division and the result will be either

  • always an integer if you use integer division, or
  • always a float if you use floating point division.

It's just the wrong way to go about testing divisibility.

ImportError: No module named 'django.core.urlresolvers'

To solve this either you down-grade the Django to any version lesser than 2.0. pip install Django==1.11.29.

ImportError: cannot import name NUMPY_MKL

If you look at the line which is causing the error, you'll see this:

from numpy._distributor_init import NUMPY_MKL  # requires numpy+mkl

This line comment states the dependency as numpy+mkl (numpy with Intel Math Kernel Library). This means that you've installed the numpy by pip, but the scipy was installed by precompiled archive, which expects numpy+mkl.

This problem can be easy solved by installation for numpy+mkl from whl file from here.

Twitter Bootstrap add active class to li

The solution is simple and there is no need for server side or ajax, you only need jQuery and Bootstrap. On every page add an id to the body tag. Use that id to find a tag that contains the page name (value of a tag).



<body id="page1">
    <ul class="nav navbar-nav">
        <li><a href="page1.html">Page1</a></li>
        <li><a href="page2.html">Page2</a></li>
    <script src="script.js"></script>


<body id="page2">
    <ul class="nav navbar-nav">
        <li><a href="page1.html">Page1</a></li>
        <li><a href="page2.html">Page2</a></li>
    <script src="script.js"></script>


    $(function () {
        $("#page1 a:contains('Page1')").parent().addClass('active');
        $("#page2 a:contains('Page2')").parent().addClass('active');

Big thanks to Ben! YouTube

Error type 3 Error: Activity class {} does not exist

Got to android/app/build.gradle and search for

 buildTypes {

You might have something like

buildTypes {
    debug {
    release {
    customBuildType {

Chose the buildType you want to start and then start the App the following

react-native run-android --variant=[buildType] --appIdSuffix '[buildType]'


react-native run-android --variant=debug --appIdSuffix 'debug'

JQuery Ajax - How to Detect Network Connection error when making Ajax call

// start snippet
error: function(XMLHttpRequest, textStatus, errorThrown) {
        if (XMLHttpRequest.readyState == 4) {
            // HTTP error (can be checked by XMLHttpRequest.status and XMLHttpRequest.statusText)
        else if (XMLHttpRequest.readyState == 0) {
            // Network error (i.e. connection refused, access denied due to CORS, etc.)
        else {
            // something weird is happening
//end snippet

explicit casting from super class to subclass

The code generates a compilation error because your instance type is an Animal:

Animal animal=new Animal();

Downcasting is not allowed in Java for several reasons. See here for details.

How can I convert an RGB image into grayscale in Python?

The tutorial is cheating because it is starting with a greyscale image encoded in RGB, so they are just slicing a single color channel and treating it as greyscale. The basic steps you need to do are to transform from the RGB colorspace to a colorspace that encodes with something approximating the luma/chroma model, such as YUV/YIQ or HSL/HSV, then slice off the luma-like channel and use that as your greyscale image. matplotlib does not appear to provide a mechanism to convert to YUV/YIQ, but it does let you convert to HSV.

Try using matplotlib.colors.rgb_to_hsv(img) then slicing the last value (V) from the array for your grayscale. It's not quite the same as a luma value, but it means you can do it all in matplotlib.


Alternatively, you could use PIL or the builtin colorsys.rgb_to_yiq() to convert to a colorspace with a true luma value. You could also go all in and roll your own luma-only converter, though that's probably overkill.

How to delete a record by id in Flask-SQLAlchemy

You can do this,



User.query.filter( == 123).delete()

Make sure to commit for delete() to take effect.

How to load external webpage in WebView

try this


<?xml version="1.0" encoding="utf-8"?>
<WebView xmlns:android=""

In your Activity:

WebView webView;
webView = (WebView)findViewById(;


Add webView.setWebViewClient(new WebViewController()); to your Activity.

WebViewController class:

public class WebViewController extends WebViewClient {

    public boolean shouldOverrideUrlLoading(WebView view, String url) {
        return true;

Force DOM redraw/refresh on Chrome/Mac

This is my solution that worked for disappearing content...

<script type = 'text/javascript'>
    var trash_div;

        if (document.body)
            if (!trash_div)
                trash_div = document.createElement('div');

    }, 1000 / 25); //25 fps...

Can iterators be reset in Python?

If you have a csv file named 'blah.csv' That looks like


you know that you can open the file for reading, and create a DictReader with

blah = open('blah.csv', 'r')
reader= csv.DictReader(blah)

Then, you will be able to get the next line with, which should output


using it again will produce


However, at this point if you use, the next time you call you will get



This seems to be the functionality you're looking for. I'm sure there are some tricks associated with this approach that I'm not aware of however. @Brian suggested simply creating another DictReader. This won't work if you're first reader is half way through reading the file, as your new reader will have unexpected keys and values from wherever you are in the file.

What is the difference between concurrent programming and parallel programming?

Just sharing an example that helps to highlight the distinction:

Parallel Programming: Say you want to implement the merge-sort algorithm. Each time that you divide the problem into two sub-problems, you can have two threads that solve them. However, in order to do the merge step you have to wait for these two threads to finish since merging requires both sub-solutions. This "mandatory wait" makes this a parallel program.

Concurrent Program: Say you want to compress n text files and generate a compressed file for each of them. You can have from 2 (up to n) threads that each handle compressing a subset of the files. When each thread is done, it's just done, it doesn't have to wait or do anything else. So, since different tasks are performed in an interleaved manner in "any arbitrary order" the program is concurrent but not parallel.

As someone else mentioned, every parallel program is concurrent (has to be in fact), but not the other way around.

How can I capture the right-click event in JavaScript?

Use the oncontextmenu event.

Here's an example:

<div oncontextmenu="javascript:alert('success!');return false;">
    Lorem Ipsum

And using event listeners (credit to rampion from a comment in 2011):

el.addEventListener('contextmenu', function(ev) {
    return false;
}, false);

Don't forget to return false, otherwise the standard context menu will still pop up.

If you are going to use a function you've written rather than javascript:alert("Success!"), remember to return false in BOTH the function AND the oncontextmenu attribute.

Shortcut for echo "<pre>";print_r($myarray);echo "</pre>";

Both old and accepted, however, I'll just leave this here:

function dump(){
    echo (php_sapi_name() !== 'cli') ? '<pre>' : '';
    foreach(func_get_args() as $arg){
        echo preg_replace('#\n{2,}#', "\n", print_r($arg, true));
    echo (php_sapi_name() !== 'cli') ? '</pre>' : '';

Takes an arbitrary number of arguments, and wraps each in <pre> for CGI requests. In CLI requests it skips the <pre> tag generation for clean output.

dump(array('foo'), array('bar', 'zip'));
CGI request                          CLI request

<pre>                                Array
Array                                (
(                                        [0] => foo
    [0] => foo                       )
)                                    Array
</pre>                               (
<pre>                                    [0] => bar
Array                                    [1] => zip
(                                    )
    [0] => bar
    [0] => zip

How to fetch data from local JSON file on react native?

Use this

import data from './customData.json';

Stop Visual Studio from launching a new browser window when starting debug?

I have solved my problem by following below steps. Go to Tools >> Click on options >> click on projects and solutions >> web projects >> uncheck "Stop debugging when browser is closed" optionenter image description here

How to set an image as a background for Frame in Swing GUI of java?

if you are using netbeans you can add a jlabel to the frame and through properties change its icon to your image and remove the text. then move the jlabel to the bottom of the Jframe or any content pane through navigator

Jetty: HTTP ERROR: 503/ Service Unavailable

None of these answers worked for me.

I had to remove all deployed java web app:

  • Windows/Show View/Other...
  • Go the the Server folder and select "Servers"
  • Right-click on the J2EE Preview at localhost
  • Click to Add and Remove... Click Remove all

Then run the project on the server

The Error is gone!

You will have to stop the server before deploying another project because it will not be found by the server. Otherwise you will get a 404 error

How to quickly edit values in table in SQL Server Management Studio?

In Mgmt Studio, when you are editing the top 200, you can view the SQL pane - either by right clicking in the grid and choosing Pane->SQL or by the button in the upper left. This will allow you to write a custom query to drill down to the row(s) you want to edit.

But ultimately mgmt studio isn't a data entry/update tool which is why this is a little cumbersome.

how to parse JSON file with GSON

In case you need to parse it from a file, I find the best solution to use a HashMap<String, String> to use it inside your java code for better manipultion.

Try out this code:

public HashMap<String, String> myMethodName() throws FileNotFoundException
    String path = "absolute path to your file";
    BufferedReader bufferedReader = new BufferedReader(new FileReader(path));

    Gson gson = new Gson();
    HashMap<String, String> json = gson.fromJson(bufferedReader, HashMap.class);
    return json;

How to change the type of a field?

You can easily convert the string data type to numerical data type.
Don't forget to change collectionName & FieldName.
for ex : CollectionNmae : Users & FieldName : Contactno.

Try this query..

db.collectionName.find().forEach( function (x) {
x.FieldName = parseInt(x.FieldName);;

How can I see the current value of my $PATH variable on OS X?

By entering $PATH on its own at the command prompt, you're trying to run it. This isn't like Windows where you can get your path output by simply typing path.

If you want to see what the path is, simply echo it:

echo $PATH

Convert Uppercase Letter to Lowercase and First Uppercase in Sentence using CSS

I know the OP is asking for a CSS-only solution. But in case anyone landing here from the Magic Google ends up requiring a JavaScript solution, here's a one-liner:

capitalize = str => str[0].toUpperCase() + str.substr(1);


capitalize('foo bar baz'); // -> 'Foo bar baz'

fatal: 'origin' does not appear to be a git repository

This does not answer your question, but I faced a similar error message but due to a different reason. Allow me to make my post for the sake of information collection.

I have a git repo on a network drive. Let's call this network drive RAID. I cloned this repo on my local machine (LOCAL) and on my number crunching cluster (CRUNCHER). For convenience I mounted the user directory of my account on CRUNCHER on my local machine. So, I can manipulate files on CRUNCHER without the need to do the work in an SSH terminal.

Today, I was modifying files in the repo on CRUNCHER via my local machine. At some point I decided to commit the files, so a did a commit. Adding the modified files and doing the commit worked as I expected, but when I called git push I got an error message similar to the one posted in the question.

The reason was, that I called push from within the repo on CRUNCHER on LOCAL. So, all paths in the config file were plain wrong.

When I realized my fault, I logged onto CRUNCHER via Terminal and was able to push the commit.

Feel free to comment if my explanation can't be understood, or you find my post superfluous.

Make a phone call programmatically

To go back to original app you can use telprompt:// instead of tel:// - The tell prompt will prompt the user first, but when the call is finished it will go back to your app:

NSString *phoneNumber = [@"telprompt://" stringByAppendingString:mymobileNO.titleLabel.text];
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:phoneNumber]];

Get week of year in JavaScript like in PHP

Not ISO-8601 week number but if the search engine pointed you here anyways.

As said above but without a class:

let now = new Date();
let onejan = new Date(now.getFullYear(), 0, 1);
let week = Math.ceil( (((now.getTime() - onejan.getTime()) / 86400000) + onejan.getDay() + 1) / 7 );

textarea's rows, and cols attribute in CSS

width and height are used when going the css route.

<!DOCTYPE html>
        <title>Setting Width and Height on Textareas</title>
            .comments { width: 300px; height: 75px }
        <textarea class="comments"></textarea>

How do I choose grid and block dimensions for CUDA kernels?

The answers above point out how the block size can impact performance and suggest a common heuristic for its choice based on occupancy maximization. Without wanting to provide the criterion to choose the block size, it would be worth mentioning that CUDA 6.5 (now in Release Candidate version) includes several new runtime functions to aid in occupancy calculations and launch configuration, see

CUDA Pro Tip: Occupancy API Simplifies Launch Configuration

One of the useful functions is cudaOccupancyMaxPotentialBlockSize which heuristically calculates a block size that achieves the maximum occupancy. The values provided by that function could be then used as the starting point of a manual optimization of the launch parameters. Below is a little example.

#include <stdio.h>

__global__ void MyKernel(int *a, int *b, int *c, int N) 
    int idx = threadIdx.x + blockIdx.x * blockDim.x; 

    if (idx < N) { c[idx] = a[idx] + b[idx]; } 

/* MAIN */
void main() 
    const int N = 1000000;

    int blockSize;      // The launch configurator returned block size 
    int minGridSize;    // The minimum grid size needed to achieve the maximum occupancy for a full device launch 
    int gridSize;       // The actual grid size needed, based on input size 

    int* h_vec1 = (int*) malloc(N*sizeof(int));
    int* h_vec2 = (int*) malloc(N*sizeof(int));
    int* h_vec3 = (int*) malloc(N*sizeof(int));
    int* h_vec4 = (int*) malloc(N*sizeof(int));

    int* d_vec1; cudaMalloc((void**)&d_vec1, N*sizeof(int));
    int* d_vec2; cudaMalloc((void**)&d_vec2, N*sizeof(int));
    int* d_vec3; cudaMalloc((void**)&d_vec3, N*sizeof(int));

    for (int i=0; i<N; i++) {
        h_vec1[i] = 10;
        h_vec2[i] = 20;
        h_vec4[i] = h_vec1[i] + h_vec2[i];

    cudaMemcpy(d_vec1, h_vec1, N*sizeof(int), cudaMemcpyHostToDevice);
    cudaMemcpy(d_vec2, h_vec2, N*sizeof(int), cudaMemcpyHostToDevice);

    float time;
    cudaEvent_t start, stop;
    cudaEventRecord(start, 0);

    cudaOccupancyMaxPotentialBlockSize(&minGridSize, &blockSize, MyKernel, 0, N); 

    // Round up according to array size 
    gridSize = (N + blockSize - 1) / blockSize; 

    cudaEventRecord(stop, 0);
    cudaEventElapsedTime(&time, start, stop);
    printf("Occupancy calculator elapsed time:  %3.3f ms \n", time);

    cudaEventRecord(start, 0);

    MyKernel<<<gridSize, blockSize>>>(d_vec1, d_vec2, d_vec3, N); 

    cudaEventRecord(stop, 0);
    cudaEventElapsedTime(&time, start, stop);
    printf("Kernel elapsed time:  %3.3f ms \n", time);

    printf("Blocksize %i\n", blockSize);

    cudaMemcpy(h_vec3, d_vec3, N*sizeof(int), cudaMemcpyDeviceToHost);

    for (int i=0; i<N; i++) {
        if (h_vec3[i] != h_vec4[i]) { printf("Error at i = %i! Host = %i; Device = %i\n", i, h_vec4[i], h_vec3[i]); return; };

    printf("Test passed\n");



The cudaOccupancyMaxPotentialBlockSize is defined in the cuda_runtime.h file and is defined as follows:

template<class T>
__inline__ __host__ CUDART_DEVICE cudaError_t cudaOccupancyMaxPotentialBlockSize(
    int    *minGridSize,
    int    *blockSize,
    T       func,
    size_t  dynamicSMemSize = 0,
    int     blockSizeLimit = 0)
    return cudaOccupancyMaxPotentialBlockSizeVariableSMem(minGridSize, blockSize, func, __cudaOccupancyB2DHelper(dynamicSMemSize), blockSizeLimit);

The meanings for the parameters is the following

minGridSize     = Suggested min grid size to achieve a full machine launch.
blockSize       = Suggested block size to achieve maximum occupancy.
func            = Kernel function.
dynamicSMemSize = Size of dynamically allocated shared memory. Of course, it is known at runtime before any kernel launch. The size of the statically allocated shared memory is not needed as it is inferred by the properties of func.
blockSizeLimit  = Maximum size for each block. In the case of 1D kernels, it can coincide with the number of input elements.

Note that, as of CUDA 6.5, one needs to compute one's own 2D/3D block dimensions from the 1D block size suggested by the API.

Note also that the CUDA driver API contains functionally equivalent APIs for occupancy calculation, so it is possible to use cuOccupancyMaxPotentialBlockSize in driver API code in the same way shown for the runtime API in the example above.

javascript filter array multiple conditions

Can also be done this way:

    this.users = this.users.filter((item) => {
                return ( > -1 ||
                item.address.toLowerCase().indexOf(val.toLowerCase()) > -1 ||
                item.age.toLowerCase().indexOf(val.toLowerCase()) > -1 ||
       > -1);

Convert array of strings to List<string>

From .Net 3.5 you can use LINQ extension method that (sometimes) makes code flow a bit better.

Usage looks like this:

using System.Linq; 

// ...

public void My()
    var myArray = new[] { "abc", "123", "zyx" };
    List<string> myList = myArray.ToList();

PS. There's also ToArray() method that works in other way.

Android M Permissions: onRequestPermissionsResult() not being called

I ran into the same issue and I just found the solution. When using the Support library, you have to use the correct method calls. For example:

  • When in AppCompatActivity, you should use ActivityCompat.requestPermissions;
  • When in, you should use simply requestPermissions (this is an instance method of

If you call ActivityCompat.requestPermissions in a fragment, the onRequestPermissionsResult callback is called on the activity and not the fragment.

Hope this helps!

Is there a way to make Firefox ignore invalid ssl-certificates?

Go to Tools > Options > Advanced "Tab"(?) > Encryption Tab

Click the "Validation" button, and uncheck the checkbox for checking validity

Be advised though that this is pretty unsecure as it leaves you wide open to accept any invalid certificate. I'd only do this if using the browser on an Intranet where the validity of the cert isn't a concern to you, or you aren't concerned in general.

Why use Optional.of over Optional.ofNullable?

Optional should mainly be used for results of Services anyway. In the service you know what you have at hand and return Optional.of(someValue) if you have a result and return Optional.empty() if you don't. In this case, someValue should never be null and still, you return an Optional.

How to create a DataFrame from a text file in Spark

If you want to use the toDF method, you have to convert your RDD of Array[String] into a RDD of a case class. For example, you have to do:

case class Test(id:String,filed2:String)
val myFile = sc.textFile("file.txt")
val df= x => x.split(";") ).map( x=> Test(x(0),x(1)) ).toDF()

how to check for null with a ng-if values in a view with angularjs?

You should check for !test, here is a fiddle showing that.

<span ng-if="!test">null</span>

Remove Backslashes from Json Data in JavaScript

You need to deserialize the JSON once before returning it as response. Please refer below code. This works for me:

JavaScriptSerializer jss = new JavaScriptSerializer();
Object finalData = jss.DeserializeObject(str);

How to read/write arbitrary bits in C/C++

just use this and feelfree:

#define BitVal(data,y) ( (data>>y) & 1)      /** Return Data.Y value   **/
#define SetBit(data,y)    data |= (1 << y)    /** Set Data.Y   to 1    **/
#define ClearBit(data,y)  data &= ~(1 << y)   /** Clear Data.Y to 0    **/
#define TogleBit(data,y)     (data ^=BitVal(y))     /** Togle Data.Y  value  **/
#define Togle(data)   (data =~data )         /** Togle Data value     **/

for example:

uint8_t number = 0x05; //0b00000101
uint8_t bit_2 = BitVal(number,2); // bit_2 = 1
uint8_t bit_1 = BitVal(number,1); // bit_1 = 0

SetBit(number,1); // number =  0x07 => 0b00000111
ClearBit(number,2); // number =0x03 => 0b0000011

Which port(s) does XMPP use?

According to Extensible Messaging and Presence Protocol (Wikipedia), the standard TCP port for the server is 5222.

The client would presumably use the same ports as the messaging protocol, but can also use http (port 80) and https (port 443) for message delivery. These have the advantage of working for users behind firewalls, so your network admin should not need to get involved.

Fragment pressing back button

This worked for me.

-Add .addToBackStack(null) when you call the new fragment from activity.

    FragmentTransaction mFragmentTransaction = getFragmentManager()

-Add onBackPressed() to your activity

public void onBackPressed() {
    if (getFragmentManager().getBackStackEntryCount() == 0) {
    } else {

python ignore certificate validation urllib2

In the meantime urllib2 seems to verify server certificates by default. The warning, that was shown in the past disappeared for 2.7.9 and I currently ran into this problem in a test environment with a self signed certificate (and Python 2.7.9).

My evil workaround (don't do this in production!):

import urllib2
import ssl

ctx = ssl.create_default_context()
ctx.check_hostname = False
ctx.verify_mode = ssl.CERT_NONE

urllib2.urlopen("https://your-test-server.local", context=ctx)

According to docs calling SSLContext constructor directly should work, too. I haven't tried that.

Returning a regex match in VBA (excel)

You need to access the matches in order to get at the SDI number. Here is a function that will do it (assuming there is only 1 SDI number per cell).

For the regex, I used "sdi followed by a space and one or more numbers". You had "sdi followed by a space and zero or more numbers". You can simply change the + to * in my pattern to go back to what you had.

Function ExtractSDI(ByVal text As String) As String

Dim result As String
Dim allMatches As Object
Dim RE As Object
Set RE = CreateObject("vbscript.regexp")

RE.pattern = "(sdi \d+)"
RE.Global = True
RE.IgnoreCase = True
Set allMatches = RE.Execute(text)

If allMatches.count <> 0 Then
    result = allMatches.Item(0).submatches.Item(0)
End If

ExtractSDI = result

End Function

If a cell may have more than one SDI number you want to extract, here is my RegexExtract function. You can pass in a third paramter to seperate each match (like comma-seperate them), and you manually enter the pattern in the actual function call:

Ex) =RegexExtract(A1, "(sdi \d+)", ", ")

Here is:

Function RegexExtract(ByVal text As String, _
                      ByVal extract_what As String, _
                      Optional seperator As String = "") As String

Dim i As Long, j As Long
Dim result As String
Dim allMatches As Object
Dim RE As Object
Set RE = CreateObject("vbscript.regexp")

RE.pattern = extract_what
RE.Global = True
Set allMatches = RE.Execute(text)

For i = 0 To allMatches.count - 1
    For j = 0 To allMatches.Item(i).submatches.count - 1
        result = result & seperator & allMatches.Item(i).submatches.Item(j)

If Len(result) <> 0 Then
    result = Right(result, Len(result) - Len(seperator))
End If

RegexExtract = result

End Function

*Please note that I have taken "RE.IgnoreCase = True" out of my RegexExtract, but you could add it back in, or even add it as an optional 4th parameter if you like.

pip or pip3 to install packages for Python 3?

This is a tricky subject. In the end, if you invoke pip it will invoke either pip2 or pip3, depending on how you set your system up.

How to check for valid email address?

Email addresses are not as simple as they seem! For example, Bob_O'[email protected], is a valid email address.

I've had some luck with the lepl package ( It can validate email addresses as indicated in RFC 3696:

Found some old code:

import lepl.apps.rfc3696
email_validator = lepl.apps.rfc3696.Email()
if not email_validator("[email protected]"):
    print "Invalid email"

Right click to select a row in a Datagridview and show a menu to delete it

private void dataGridView1_CellContextMenuStripNeeded(object sender, 
DataGridViewCellContextMenuStripNeededEventArgs e)
    if (e.RowIndex != -1)
        this.dataGridView1.Rows[e.RowIndex].Selected = true;
        e.ContextMenuStrip = contextMenuStrip1;

Escape double quote in grep

The problem is that you aren't correctly escaping the input string, try:

echo "\"member\":\"time\"" | grep -e "member\""

Alternatively, you can use unescaped double quotes within single quotes:

echo '"member":"time"' | grep -e 'member"'

It's a matter of preference which you find clearer, although the second approach prevents you from nesting your command within another set of single quotes (e.g. ssh 'cmd').

Reverse HashMap keys and values in Java

Tested with below sample snippet, tried with MapUtils, and Java8 Stream feature. It worked with both cases.

public static void main(String[] args) {
    Map<String, String> test = new HashMap<String, String>();
    test.put("a", "1");
    test.put("d", "1");
    test.put("b", "2");
    test.put("c", "3");
    test.put("d", "4");
    test.put("d", "41");


    Map<String, String> test1 = MapUtils.invertMap(test);


    Map<String, String> mapInversed = 
               .collect(Collectors.toMap(Map.Entry::getValue, Map.Entry::getKey));


{a=1, b=2, c=3, d=41}
{1=a, 2=b, 3=c, 41=d}
{1=a, 2=b, 3=c, 41=d}

How to solve "Kernel panic - not syncing - Attempted to kill init" -- without erasing any user data

Mount remount the /

  1. mount -o remount,rw /dev/xyz /
  2. sed -i 's/1 1/0 0/' /etc/fstab
  3. sed -i 's/1 2/0 0/' /etc/fstab
  4. reboot

Is there a way to get version from package.json in nodejs code?

Or in plain old shell:

$ node -e "console.log(require('./package.json').version);"

This can be shortened to

$ node -p "require('./package.json').version"

Android: Quit application when press back button

try this

Intent a = new Intent(Intent.ACTION_MAIN);

How to connect to a secure website using SSL in Java with a pkcs12 file?

I realise that this article may be outdated but still I would like to ask smithsv to correct his source code, it contains many mistakes, I managed to correct most of them but still don't know what kind of object x509 could be.Here is the source code as I think is should be:

import java.util.Enumeration;


public class Connection2 {
    public void connect() {
         * This is an example to use ONLY p12 file it's not optimazed but it
         * work. The pkcs12 file where generated by OpenSSL by me. Example how
         * to load p12 file and build Trust zone from it... It outputs
         * certificates from p12 file and add good certs to TrustStore
        KeyStore ks = KeyStore.getInstance( "pkcs12" );
        ks.load( new FileInputStream( cert.pfx ), "passwrd".toCharArray() );

        KeyStore jks = KeyStore.getInstance( "JKS" );
        jks.load( null );

        for( Enumeration t = ks.aliases(); t.hasMoreElements(); ) {
            String alias = (String )t.nextElement();
            System.out.println( "@:" + alias );
            if( ks.isKeyEntry( alias ) ) {
                Certificate[] a = ks.getCertificateChain( alias );
                for( int i = 0; i == 0; )
                    jks.setCertificateEntry( x509Cert.getSubjectDN().toString(), x509 );

                System.out.println( ks.getCertificateAlias( x509 ) );
                System.out.println( "ok" );

        System.out.println( "init Stores..." );

        KeyManagerFactory kmf = KeyManagerFactory.getInstance( "SunX509" );
        kmf.init( ks, "c1".toCharArray() );

        TrustManagerFactory tmf = TrustManagerFactory.getInstance( "SunX509" );
        tmf.init( jks );

        SSLContext ctx = SSLContext.getInstance( "TLS" );
        ctx.init( kmf.getKeyManagers(), tmf.getTrustManagers(), null );

multiple figure in latex with captions

Look at the Subfloats section of,_Figures_and_Captions.


  \subfloat[Subcaption 1]{\label{figur:1}\includegraphics[width=60mm]{explicit3185.eps}}
  \subfloat[Subcaption 2]{\label{figur:2}\includegraphics[width=60mm]{explicit3183.eps}}
  \subfloat[Subcaption 3]{\label{figur:3}\includegraphics[width=60mm]{explicit1501.eps}}
  \subfloat[Subcaption 4]{\label{figur:4}\includegraphics[width=60mm]{explicit23185.eps}}
  \subfloat[Subcaption 5]{\label{figur:5}\includegraphics[width=60mm]{explicit23183.eps}}
  \subfloat[Subcaption 6]{\label{figur:6}\includegraphics[width=60mm]{explicit21501.eps}}


How to Remove the last char of String in C#?

newString = yourString.Substring(0, yourString.length -1);

Your project contains error(s), please fix it before running it

If none of the above solution work, you should check the READ ONLY property of the Project folder, if it is Read-Only, the compiler will not be able to overwrite the resources, and other dex APK etc files and hence this will occur.. This happened to me and I fixed after a long struggle.. Happy Programming.

How to get a .csv file into R?

You mention that you will call on each vertical column so that you can perform calculations. I assume that you just want to examine each single variable. This can be done through the following.

df <- read.csv("myRandomFile.csv", header=TRUE)




Might be helpful just to assign the data to a variable.

var3 <- df$GPA

How do I protect javascript files?

Good question with a simple answer: you can't!

Javascript is a client-side programming language, therefore it works on the client's machine, so you can't actually hide anything from the client.
Obfuscating your code is a good solution, but it's not enough, because, although it is hard, someone could decipher your code and "steal" your script.
There are a few ways of making your code hard to be stolen, but as i said nothing is bullet-proof.

Off the top of my head, one idea is to restrict access to your external js files from outside the page you embed your code in. In that case, if you have

<script type="text/javascript" src="myJs.js"></script>

and someone tries to access the myJs.js file in browser, he shouldn't be granted any access to the script source.
For example, if your page is written in php, you can include the script via the include function and let the script decide if it's safe" to return it's source.
In this example, you'll need the external "js" (written in php) file myJs.php :

    if ($URL != "")
    die("/\*sry, no acces rights\*/");
// your obfuscated script goes here

that would be included in your main page my-page.php :

<script type="text/javascript">
    <?php include "myJs.php"; ?>;

This way, only the browser could see the js file contents.

Another interesting idea is that at the end of your script, you delete the contents of your dom script element, so that after the browser evaluates your code, the code disappears :

<script id="erasable" type="text/javascript">
    //your code goes here
    document.getElementById('erasable').innerHTML = "";

These are all just simple hacks that cannot, and I can't stress this enough : cannot, fully protect your js code, but they can sure piss off someone who is trying to "steal" your code.


I recently came across a very interesting article written by Patrick Weid on how to hide your js code, and he reveals a different approach: you can encode your source code into an image! Sure, that's not bullet proof either, but it's another fence that you could build around your code.
The idea behind this approach is that most browsers can use the canvas element to do pixel manipulation on images. And since the canvas pixel is represented by 4 values (rgba), each pixel can have a value in the range of 0-255. That means that you can store a character (actual it's ascii code) in every pixel. The rest of the encoding/decoding is trivial.
Thanks, Patrick!

Where is my m2 folder on Mac OS X Mavericks

If you have used brew to install maven, create .m2 directory and then copy settings.xml in .m2 directory.

mkdir ~/.m2
cp /usr/local/Cellar/maven32/3.2.5/libexec/conf/settings.xml ~/.m2

You may need to change the maven version in the path, mine is 3.2.5