Programs & Examples On #Tile engine

move column in pandas dataframe

I use Pokémon database as an example, the columns for my data base are

['Name', '#', 'Type 1', 'Type 2', 'Total', 'HP', 'Attack', 'Defense', 'Sp. Atk', 'Sp. Def', 'Speed', 'Generation', 'Legendary']

Here is the code:

import pandas as pd
    df = pd.read_html('')[0] 
    cols = df.columns.to_list()
    cos_end= ["Name", "Total", "HP", "Defense"]

    for i, j in enumerate(cos_end, start=(len(cols)-len(cos_end))):
        cols.insert(i, cols.pop(cols.index(j)))
    df = df.reindex(columns=cols)


Populating Spring @Value during Unit Test

If possible I would try to write those test without Spring Context. If you create this class in your test without spring, then you have full control over its fields.

To set the @value field you can use Springs ReflectionTestUtils - it has a method setField to set private fields.

@see JavaDoc: ReflectionTestUtils.setField(java.lang.Object, java.lang.String, java.lang.Object)

Checking for #N/A in Excel cell from VBA code

First check for an error (N/A value) and then try the comparisation against cvErr(). You are comparing two different things, a value and an error. This may work, but not always. Simply casting the expression to an error may result in similar problems because it is not a real error only the value of an error which depends on the expression.

If IsError(ActiveWorkbook.Sheets("Publish").Range("G4").offset(offsetCount, 0).Value) Then
  If (ActiveWorkbook.Sheets("Publish").Range("G4").offset(offsetCount, 0).Value <> CVErr(xlErrNA)) Then
    'do something
  End If
End If

How to create a floating action button (FAB) in android, using AppCompat v21?

There are a bunch of libraries out there add a FAB(Floating Action Button) in your app, Here are few of them i Know.

makovkastar's FAB

futuersimple's Composite FAB

Material Design library which includes FAB too

All these libraries are supported on pre-lollipop devices, minimum to api 8

How to obtain image size using standard Python class (without using external library)?

Kurts answer needed to be slightly modified to work for me.

First, on ubuntu: sudo apt-get install python-imaging


from PIL import Image
im.size # (width,height) tuple

Check out the handbook for more info.

Angular 2 Checkbox Two Way Data Binding

In Angular p-checkbox,

Use all attributes of p-checkbox

<p-checkbox name="checkbox" value="isAC" 
    label="All Colors" [(ngModel)]="selectedAllColors" 
    [ngModelOptions]="{standalone: true}" id="al" 

And more importantly, don't forget to include [ngModelOptions]="{standalone: true} as well as it SAVED MY DAY.

How can I change IIS Express port for a site

If you just want to change the port because it is already in use. Follow the following steps.

In Visual studio

  1. Right-click on Project Node and Unload Project
  2. Right-click on Project Node and Edit .csproj file.
  3. Search for the following tags and remove them
  1. press Ctrl + S to save the document
  2. Right-click on Project Node and load Project

It will work by selecting another port randomly.

For further information. please click

Bootstrap Modal Backdrop Remaining

After perform action just trigger the close button.



Why does git status show branch is up-to-date when changes exist upstream?

Let look into a sample git repo to verify if your branch (master) is up to date with origin/master.

Verify that local master is tracking origin/master:

$ git branch -vv
* master a357df1eb [origin/master] This is a commit message

More info about local master branch:

$ git show --summary
commit a357df1eb941beb5cac3601153f063dae7faf5a8 (HEAD -> master, tag: 2.8.0, origin/master, origin/HEAD)
Author: ...
Date:   Tue Dec 11 14:25:52 2018 +0100

    Another commit message

Verify if origin/master is on the same commit:

$ cat .git/packed-refs | grep origin/master
a357df1eb941beb5cac3601153f063dae7faf5a8 refs/remotes/origin/master

We can see the same hash around, and safe to say the branch is in consistency with the remote one, at least in the current git repo.

Are HTTP headers case-sensitive?

officially, headers are case insensitive, however, it is common practice to capitalize the first letter of every word.
but, because it is common practice, certain programs like IE assume the headers are capitalized.
so while the docs say the are case insensitive, bad programmers have basically changed the docs.

How to send a simple email from a Windows batch file?

$emailSmtpServerPort = "587"
$emailSmtpUser = "username"
$emailSmtpPass = 'password'
$emailMessage = New-Object System.Net.Mail.MailMessage
$emailMessage.From = "[From email address]"
$emailMessage.To.Add( "[Send to email address]" )
$emailMessage.Subject = "Testing e-mail"
$emailMessage.IsBodyHtml = $true
$emailMessage.Body = @"
<p>Here is a message that is <strong>HTML formatted</strong>.</p>
<p>From your friendly neighborhood IT guy</p>
$SMTPClient = New-Object System.Net.Mail.SmtpClient( $emailSmtpServer , $emailSmtpServerPort )
$SMTPClient.EnableSsl = $true
$SMTPClient.Credentials = New-Object System.Net.NetworkCredential( $emailSmtpUser , $emailSmtpPass );
$SMTPClient.Send( $emailMessage )

How to retrieve current workspace using Jenkins Pipeline Groovy script?

A quick note for anyone who is using bat in the job and needs to access Workspace:

It won't work.

$WORKSPACE as mentioned here only works with PowerShell. So your code should have powershell for execution

 stage('Verifying Workspace') {
  powershell label: '', script: 'dir $WORKSPACE'

What equivalents are there to TortoiseSVN, on Mac OSX?

My previous version of this answer had links, that kept becoming dead.
So, I've pointed it to the internet archive to preserve the original answer.

Subversion client releases for Windows and Macintosh

Wiki - Subversion clients comparison table

How to simulate a real mouse click using java?

You could create a simple AutoIt Script that does the job for you, compile it as an executable and perform a system call there.

in au3 Script:

; how to use: MouseClick ( "button" [, x, y [, clicks = 1 [, speed = 10]]] )
MouseClick ( "left" , $CmdLine[1], $CmdLine[1] )

Now find aut2exe in your au3 Folder or find 'Compile Script to .exe' in your Start Menu and create an executable.

in your Java class call:

    new String[]{

AutoIt will behave as if it was a human and won't be detected as a machine.

Find AutoIt here:

How to get MAC address of your machine using a C program?

Assuming that c++ code (c++11) is okay as well and the interface is known.

#include <cstdint>
#include <fstream>
#include <streambuf>
#include <regex>

using namespace std;

uint64_t getIFMAC(const string &ifname) {
  ifstream iface("/sys/class/net/" + ifname + "/address");
  string str((istreambuf_iterator<char>(iface)), istreambuf_iterator<char>());
  if (str.length() > 0) {
    string hex = regex_replace(str, std::regex(":"), "");
    return stoull(hex, 0, 16);
  } else {
    return 0;
int main()
  string iface = "eth0";
  printf("%s: mac=%016llX\n", iface.c_str(), getIFMAC(iface));

What is the meaning of polyfills in HTML5?

First off let's clarify what a polyfil is not: A polyfill is not part of the HTML5 Standard. Nor is a polyfill limited to Javascript, even though you often see polyfills being referred to in those contexts.

The term polyfill itself refers to some code that "allows you to have some specific functionality that you expect in current or “modern” browsers to also work in other browsers that do not have the support for that functionality built in. "

Source and example of polyfill here:

How to define unidirectional OneToMany relationship in JPA

My bible for JPA work is the Java Persistence wikibook. It has a section on unidirectional OneToMany which explains how to do this with a @JoinColumn annotation. In your case, i think you would want:

private Set<Text> text;

I've used a Set rather than a List, because the data itself is not ordered.

The above is using a defaulted referencedColumnName, unlike the example in the wikibook. If that doesn't work, try an explicit one:

@JoinColumn(name="TXTHEAD_CODE", referencedColumnName="DATREG_META_CODE")
private Set<Text> text;

Visual Studio Expand/Collapse keyboard shortcuts

Collapse to definitions


Expand all outlining


Expand or collapse everything


This also works with other languages like TypeScript and JavaScript

Enable/Disable a dropdownbox in jquery

I am using JQuery > 1.8 and this works for me...

$('#dropDownId').attr('disabled', true);

notifyDataSetChanged example

I had the same problem and I prefer not to replace the entire ArrayAdapter with a new instance continuously. Thus I have the AdapterHelper do the heavy lifting somewhere else.

Add this where you would normally (try to) call notify

new AdapterHelper().update((ArrayAdapter)adapter, new ArrayList<Object>(yourArrayList));

AdapterHelper class

public class AdapterHelper {
    @SuppressWarnings({ "rawtypes", "unchecked" })
    public void update(ArrayAdapter arrayAdapter, ArrayList<Object> listOfObject){
        for (Object object : listOfObject){

Comparing strings in Java

[EDIT] I made a mistake earlier, because, to get the text, you need to use .getText().toString().

Here is a full working example:

package com.psegina.passwordTest01;

import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.Toast;

public class Main extends Activity implements OnClickListener {
    LinearLayout l;
    EditText user;
    EditText pwd;
    Button btn;

    public void onCreate(Bundle savedInstanceState) {

        l = new LinearLayout(this);
        user = new EditText(this);
        pwd = new EditText(this);
        btn = new Button(this);



    public void onClick(View v){
        String u = user.getText().toString();
        String p = pwd.getText().toString();
        if( u.equals( p ) )
            Toast.makeText(getApplicationContext(), "Matches", Toast.LENGTH_SHORT).show();
            Toast.makeText(getApplicationContext(), user.getText()+" != "+pwd.getText(), Toast.LENGTH_SHORT).show();

Original answer (Will not work because of the lack of toString())

Try using .getText() instead of .toString().

if( passw1.getText() == passw2.getText() )
#do something

.toString() returns a String representation of the whole object, meaning it won't return the text you entered in the field (see for yourself by adding a Toast which will show the output of .toString())

Ruby on Rails generates model field:type - what are the options for field:type?

:primary_key, :string, :text, :integer, :float, :decimal, :datetime, :timestamp,
:time, :date, :binary, :boolean, :references

See the table definitions section.

How do I initialize a dictionary of empty lists in Python?

You are populating your dictionaries with references to a single list so when you update it, the update is reflected across all the references. Try a dictionary comprehension instead. See Create a dictionary with list comprehension in Python

d = {k : v for k in blah blah blah}

Python error "ImportError: No module named"

Yup. You need the directory to contain the file, which is the file that initializes the package. Here, have a look at this.

The files are required to make Python treat the directories as containing packages; this is done to prevent directories with a common name, such as string, from unintentionally hiding valid modules that occur later on the module search path. In the simplest case, can just be an empty file, but it can also execute initialization code for the package or set the __all__ variable, described later.

Accessing clicked element in angularjs

While AngularJS allows you to get a hand on a click event (and thus a target of it) with the following syntax (note the $event argument to the setMaster function; documentation here:

function AdminController($scope) {    
  $scope.setMaster = function(obj, $event){

this is not very angular-way of solving this problem. With AngularJS the focus is on the model manipulation. One would mutate a model and let AngularJS figure out rendering.

The AngularJS-way of solving this problem (without using jQuery and without the need to pass the $event argument) would be:

<div ng-controller="AdminController">
    <ul class="list-holder">
        <li ng-repeat="section in sections" ng-class="{active : isSelected(section)}">
            <a ng-click="setMaster(section)">{{}}</a>
    {{selected | json}}

where methods in the controller would look like this:

$scope.setMaster = function(section) {
    $scope.selected = section;

$scope.isSelected = function(section) {
    return $scope.selected === section;

Here is the complete jsFiddle:

Best way to generate xml?

Using lxml:

from lxml import etree

# create XML 
root = etree.Element('root')
# another child with text
child = etree.Element('child')
child.text = 'some text'

# pretty string
s = etree.tostring(root, pretty_print=True)
print s


  <child>some text</child>

See the tutorial for more information.

How to install maven on redhat linux

Go to and check what is the latest tar.gz file

Supposing it is e.g. apache-maven-3.2.1-bin.tar.gz, from the command line; you should be able to simply do:


And then proceed to install it.

UPDATE: Adding complete instructions (copied from the comment below)

  1. Run command above from the dir you want to extract maven to (e.g. /usr/local/apache-maven)
  2. run the following to extract the tar:

    tar xvf apache-maven-3.2.1-bin.tar.gz
  3. Next add the env varibles such as

    export M2_HOME=/usr/local/apache-maven/apache-maven-3.2.1

    export M2=$M2_HOME/bin

    export PATH=$M2:$PATH

  4. Verify

    mvn -version

What is the difference between max-device-width and max-width for mobile web?

If you are making a cross-platform app (eg. using phonegap/cordova) then,

Don't use device-width or device-height. Rather use width or height in CSS media queries because Android device will give problems in device-width or device-height. For iOS it works fine. Only android devices doesn't support device-width/device-height.

Spring AMQP + RabbitMQ 3.3.5 ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN

The error

ACCESS_REFUSED - Login was refused using authentication mechanism PLAIN. For details see the broker logfile.

can occur if the credentials that your application is trying to use to connect to RabbitMQ are incorrect or missing.

I had this happen when the RabbitMQ credentials stored in my ASP.NET application's web.config file had a value of "" for the password instead of the actual password string value.

Javascript array search and remove string?

I'm actually updating this thread with a more recent 1-line solution:

let arr = ['A', 'B', 'C'];
arr = arr.filter(e => e !== 'B'); // will return ['A', 'C']

The idea is basically to filter the array by selecting all elements different to the element you want to remove.

Note: will remove all occurrences.


If you want to remove only the first occurence:

t = ['A', 'B', 'C', 'B'];
t.splice(t.indexOf('B'), 1); // will return ['B'] and t is now equal to ['A', 'C', 'B']


Update to the answer

if you want multiple columns, that can be achived like this:

update file1
  (firstfield, secondfield) = (
        select 'stuff' concat 'something from file2', 
               'some secondfield value' 
        from file2
        where substr(file1.field1, 10, 20) = substr(,1,10) )
where like 'BLAH%'


Why is the GETDATE() an invalid identifier

getdate() for MS-SQL, sysdate for Oracle server

jQuery won't parse my JSON from AJAX query

I had a similar problem to this where Firefox 3.5 worked fine and parsed my JSON data but Firefox 3.0.6 returned a parseerror. Turned out it was a blank space at the start of the JSON that caused Firefox 3.0.6 to throw an error. Removing the blank space fixed it

How to update npm

if user3223763's answer doesn't works, you can try this:

sudo apt-get remove nodejs ^node-* nodejs-*
sudo apt-get autoremove
sudo apt-get clean
curl -sL | sudo -E bash -
sudo apt-get install nodejs

Then :

curl | sh

After this, open a new terminal and check the npm version:

npm --version


Today the last nvm version is :

Thus the CURL command is: v0.25.4 instead of v0.13.1

curl | sh

You can check to use the correct version for further upgrades

Add element to a JSON file?

You can do this.

data[0]['f'] = var

Visual Studio replace tab with 4 spaces?

For VS2010 and above (VS2010 needs a plugin). If you have checked/set the options of the tab size in Visual Studio but it still won't work. Then check if you have a .editorconfig file in your project! This will override the Visual Studio settings. Edit the tab-size in that file.

This can happen if you install an Angular application in your project with the Angular-Cli.

See MSDN blog

How to get the ASCII value in JavaScript for the characters

Here is the example:

var charCode = "a".charCodeAt(0);_x000D_

Or if you have longer strings:

var string = "Some string";_x000D_
for (var i = 0; i < string.length; i++) {_x000D_

String.charCodeAt(x) method will return ASCII character code at a given position.

C++ Object Instantiation

I've seen this anti-pattern from people who don't quite get the & address-of operator. If they need to call a function with a pointer, they'll always allocate on the heap so they get a pointer.

void FeedTheDog(Dog* hungryDog);

Dog* badDog = new Dog;
delete badDog;

Dog goodDog;

How to loop over files in directory and change path and add suffix to filename

A couple of notes first: when you use Data/data1.txt as an argument, should it really be /Data/data1.txt (with a leading slash)? Also, should the outer loop scan only for .txt files, or all files in /Data? Here's an answer, assuming /Data/data1.txt and .txt files only:

for filename in /Data/*.txt; do
    for ((i=0; i<=3; i++)); do
        ./MyProgram.exe "$filename" "Logs/$(basename "$filename" .txt)_Log$i.txt"


  • /Data/*.txt expands to the paths of the text files in /Data (including the /Data/ part)
  • $( ... ) runs a shell command and inserts its output at that point in the command line
  • basename somepath .txt outputs the base part of somepath, with .txt removed from the end (e.g. /Data/file.txt -> file)

If you needed to run MyProgram with Data/file.txt instead of /Data/file.txt, use "${filename#/}" to remove the leading slash. On the other hand, if it's really Data not /Data you want to scan, just use for filename in Data/*.txt.

pip issue installing almost any library

If you're connecting through a proxy, execute export https_proxy=<your_proxy> (on Unix or Git Bash) and then retry installation.

If you're using Windows cmd, this changes to set https_proxy=<your_proxy>.

ValueError: unsupported pickle protocol: 3, python2 pickle can not load the file dumped by python 3 pickle?

Pickle uses different protocols to convert your data to a binary stream.

You must specify in python 3 a protocol lower than 3 in order to be able to load the data in python 2. You can specify the protocol parameter when invoking pickle.dump.

MySQL Alter Table Add Field Before or After a field already present

$query = "ALTER TABLE `" . $table_prefix . "posts_to_bookmark` 
          ADD COLUMN `ping_status` INT(1) NOT NULL 

I believe you need to have ADD COLUMN and use AFTER, not BEFORE.

In case you want to place column at the beginning of a table, use the FIRST statement:

$query = "ALTER TABLE `" . $table_prefix . "posts_to_bookmark`
          ADD COLUMN `ping_status` INT(1) NOT NULL 

Angularjs if-then-else construction in expression

You can easily use ng-show such as :

    <div ng-repeater="item in items">
        <div ng-show="isExists(item)">available</div>
        <div ng-show="!isExists(item)">oh no, you don't have it</div>

For more complex tests, you can use ng-switch statements :

    <div ng-repeater="item in items">
        <div ng-switch on="isExists(item)">
            <span ng-switch-when="true">Available</span>
            <span ng-switch-default>oh no, you don't have it</span>

Post request with Wget?

Wget currently only supports x-www-form-urlencoded data. --post-file is not for transmitting files as form attachments, it expects data with the form: key=value&otherkey=example.

--post-data and --post-file work the same way: the only difference is that --post-data allows you to specify the data in the command line, while --post-file allows you to specify the path of the file that contain the data to send.

Here's the documentation:

           Use POST as the method for all HTTP requests and send the specified data
           in the request body.  --post-data sends string as data, whereas
           --post-file sends the contents of file.  Other than that, they work in
           exactly the same way. In particular, they both expect content of the
           form "key1=value1&key2=value2", with percent-encoding for special
           characters; the only difference is that one expects its content as a
           command-line parameter and the other accepts its content from a file. In
           particular, --post-file is not for transmitting files as form
           attachments: those must appear as "key=value" data (with appropriate
           percent-coding) just like everything else. Wget does not currently
           support "multipart/form-data" for transmitting POST data; only
           "application/x-www-form-urlencoded". Only one of --post-data and
           --post-file should be specified.

Regarding your authentication token, it should either be provided in the header, in the path of the url, or in the data itself. This must be indicated somewhere in the documentation of the service you use. In a POST request, as in a GET request, you must specify the data using keys and values. This way the server will be able to receive multiple information with specific names. It's similar with variables.

Hence, you can't just send a magic token to the server, you also need to specify the name of the key. If the key is "token", then it should be token=YOUR_TOKEN.

wget --post-data 'user=foo&password=bar'

Also, you should consider using curl if you can because it is easier to send files using it. There are many examples on the Internet for that.

in python how do I convert a single digit number into a double digits string?

df["col_name"].str.rjust(4,'0')#(length of string,'value') --> ValueXXX --> 0XXX  
df["col_name"].str.ljust(4,'0')#(length of string,'value') --> XXXValue --> XXX0

How to obtain the number of CPUs/cores in Linux from the command line?

It is very simple. Just use this command:


Convert pyspark string to date format

Try this:

df = spark.createDataFrame([('2018-07-27 10:30:00',)], ['Date_col']), 'yyyy-MM-dd HH:mm:ss')).alias('dt_col'))
|           Date_col|  
|2018-07-27 10:30:00|  

How can I introduce multiple conditions in LIKE operator?

I also had the same requirement where I didn't have choice to pass like operator multiple times by either doing an OR or writing union query.

This worked for me in Oracle 11g:

REGEXP_LIKE (column, 'ABC.*|XYZ.*|PQR.*'); 

Download file from an ASP.NET Web API method using AngularJS

C# WebApi PDF download all working with Angular JS Authentication

Web Api Controller

    public HttpResponseMessage OpenFile(int QRFileId)
        QRFileRepository _repo = new QRFileRepository();
        var QRFile = _repo.GetQRFileById(QRFileId);
        if (QRFile == null)
            return new HttpResponseMessage(HttpStatusCode.BadRequest);
        string path = ConfigurationManager.AppSettings["QRFolder"] + + QRFile.QRId + @"\" + QRFile.FileName;
        if (!File.Exists(path))
            return new HttpResponseMessage(HttpStatusCode.BadRequest);

        HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
        //response.Content = new StreamContent(new FileStream(localFilePath, FileMode.Open, FileAccess.Read));
        Byte[] bytes = File.ReadAllBytes(path);
        //String file = Convert.ToBase64String(bytes);
        response.Content = new ByteArrayContent(bytes);
        response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
        response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/pdf");
        response.Content.Headers.ContentDisposition.FileName = QRFile.FileName;

        return response;

Angular JS Service

this.getPDF = function (apiUrl) {
            var headers = {};
            headers.Authorization = 'Bearer ' + sessionStorage.tokenKey;
            var deferred = $q.defer();
                hostApiUrl + apiUrl,
                    responseType: 'arraybuffer',
                    headers: headers
            .success(function (result, status, headers) {
             .error(function (data, status) {
                 console.log("Request failed with status: " + status);
            return deferred.promise;

        this.getPDF2 = function (apiUrl) {
            var promise = $http({
                method: 'GET',
                url: hostApiUrl + apiUrl,
                headers: { 'Authorization': 'Bearer ' + sessionStorage.tokenKey },
                responseType: 'arraybuffer'
            promise.success(function (data) {
                return data;
            }).error(function (data, status) {
                console.log("Request failed with status: " + status);
            return promise;

Either one will do

Angular JS Controller calling the service

vm.open3 = function () {
        var downloadedData = crudService.getPDF('ClientQRDetails/openfile/29');
        downloadedData.then(function (result) {
            var file = new Blob([result], { type: 'application/pdf;base64' });
            var fileURL = window.URL.createObjectURL(file);
            var seconds = new Date().getTime() / 1000;
            var fileName = "cert" + parseInt(seconds) + ".pdf";
            var a = document.createElement("a");
   = "display: none";
            a.href = fileURL;
   = fileName;

And last the HTML page

<a class="btn btn-primary" ng-click="vm.open3()">FILE Http with crud service (3 getPDF)</a>

This will be refactored just sharing the code now hope it helps someone as it took me a while to get this working.

How to force a script reload and re-execute?

How about adding a new script tag to <head> with the script to (re)load? Something like below:

   function load_js()
      var head= document.getElementsByTagName('head')[0];
      var script= document.createElement('script');
      script.src= 'source_file.js';

The main point is inserting a new script tag -- you can remove the old one without consequence. You may need to add a timestamp to the query string if you have caching issues.

How to remove an element from an array in Swift

extension to remove String object

extension Array {
    mutating func delete(element: String) {
        self = self.filter() { $0 as! String != element }

How to Display Selected Item in Bootstrap Button Dropdown Title

Here is my version of this which I hope can save some of your time :)

enter image description here jQuery PART:

$(".dropdown-menu").on('click', 'li a', function(){
  var selText = $(this).children("h4").html();



<div class="container">
  <div class="btn-group">
    <a class="btn btn-default dropdown-toggle btn-blog " data-toggle="dropdown" href="#" id="dropdownMenu1" style="width:200px;"><span class="selection pull-left">Select an option </span> 
      <span class="pull-right glyphiconglyphicon-chevron-down caret" style="float:right;margin-top:10px;"></span></a>

     <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu1">
       <li><a href="#" class="" data-value=1><p> HER Can you write extra text or <b>HTLM</b></p> <h4> <span class="glyphicon glyphicon-plane"></span>  <span> Your Option 1</span> </h4></a>  </li>
       <li><a href="#" class="" data-value=2><p> HER Can you write extra text or <i>HTLM</i> or some long long long long long long long long long long text </p><h4> <span class="glyphicon glyphicon-briefcase"></span> <span>Your Option 2</span>  </h4></a>
      <li class="divider"></li>
   <li><a href="#" class="" data-value=3><p> HER Can you write extra text or <b>HTLM</b> or some </p><h4> <span class="glyphicon glyphicon-heart text-danger"></span> <span>Your Option 3</span>  </h4></a>
  <input type="text" id="vl" />

How to read and write excel file

For reading data from .xlsx workbooks we need to use XSSFworkbook classes.

XSSFWorkbook xlsxBook = new XSSFWorkbook(fis);

XSSFSheet sheet = xlsxBook.getSheetAt(0); etc.

We need to use Apache-poi 3.9 @

For detailed info with example visit :

entity framework Unable to load the specified metadata resource

Craig Stuntz has written an extensive (in my opinion) blog post on troubleshooting this exact error message, I personally would start there.

The following res: (resource) references need to point to your model.

<add name="Entities" connectionString="metadata=

Make sure each one has the name of your .edmx file after the "*/", with the "edmx" changed to the extension for that res (.csdl, .ssdl, or .msl).

It also may help to specify the assembly rather than using "//*/".

Worst case, you can check everything (a bit slower but should always find the resource) by using

<add name="Entities" connectionString="metadata=
        res://*/;provider= <!-- ... -->

Android Gradle 5.0 Update:Cause: org.jetbrains.plugins.gradle.tooling.util

I have same problem after upgrading to Gradle Wrapper 5.1.rec3. I am back to Gradle 4.6

How to switch activity without animation in Android?

Try this code,

this.startActivity(new Intent(v.getContext(), newactivity.class).addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION));

Clear the value of bootstrap-datepicker

I know its too late to answer, but in my scenario below code was not working.


here is my solution.


I did clear datepicker value first then removed datepicker and again reinitialize datepicker. its resolved my problem.

How do I use raw_input in Python 3

How about the following one? Should allow you to use either raw_input or input in both Python2 and Python3 with the semantics of Python2's raw_input (aka the semantics of Python3's input)

# raw_input isn't defined in Python3.x, whereas input wasn't behaving like raw_input in Python 2.x
# this should make both input and raw_input work in Python 2.x/3.x like the raw_input from Python 2.x 
try: input = raw_input
except NameError: raw_input = input

Laravel Request getting current path with query string

Get the flag parameter from the URL string

public function create(Request $request)
$flag = $request->input('flag');
return view('hf.create', compact('page_title', 'page_description', 'flag'));

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

Run this code in your powershell or cmd

Set-ExecutionPolicy -Scope Process -ExecutionPolicy Bypass

Has anyone gotten HTML emails working with Twitter Bootstrap?

Emails require tables in order to work properly.

Inky (by foundation for emails) is a templating language that converts simple HTML tags into the complex table HTML required for emails.




  <table align="center" class="container">
          <table class="row">
                <th class="small-12 large-12 columns first last">
                        <th>Put content in me!</th>
                        <th class="expander"></th>


Will produce this:

enter image description here

DateTime vs DateTimeOffset

This piece of code from Microsoft explains everything:

// Find difference between Date.Now and Date.UtcNow
  date1 = DateTime.Now;
  date2 = DateTime.UtcNow;
  difference = date1 - date2;
  Console.WriteLine("{0} - {1} = {2}", date1, date2, difference);

  // Find difference between Now and UtcNow using DateTimeOffset
  dateOffset1 = DateTimeOffset.Now;
  dateOffset2 = DateTimeOffset.UtcNow;
  difference = dateOffset1 - dateOffset2;
  Console.WriteLine("{0} - {1} = {2}", 
                    dateOffset1, dateOffset2, difference);
  // If run in the Pacific Standard time zone on 4/2/2007, the example
  // displays the following output to the console:
  //    4/2/2007 7:23:57 PM - 4/3/2007 2:23:57 AM = -07:00:00
  //    4/2/2007 7:23:57 PM -07:00 - 4/3/2007 2:23:57 AM +00:00 = 00:00:00

MySQL maximum memory usage

We use these settings:

innodb_buffer_pool_size = 384M
key_buffer = 256M
query_cache_size = 1M
query_cache_limit = 128M
thread_cache_size = 8
max_connections = 400
innodb_lock_wait_timeout = 100

for a server with the following specifications:

Dell Server
CPU cores: Two
Processor(s): 1x Dual Xeon
Clock Speed: >= 2.33GHz
RAM: 2 GBytes
Disks: 1×250 GB SATA

int to hex string

Previous answer is not good for negative numbers. Use a short type instead of int

        short iValue = -1400;
        string sResult = iValue.ToString("X2");
        Console.WriteLine("Value={0} Result={1}", iValue, sResult);

Now result is FA88

How to convert Blob to File in JavaScript

This problem was bugg me for hours. I was using Nextjs and trying to convert canvas to an image file.

I just use the other guy's solution but the created file was empty.

So if this is your problem you should mention the size property in the file object.

new File([Blob], `my_image${new Date()}.jpeg`, {
  type: "image/jpeg",
  lastModified: new Date(),
  size: 2,

just add it, the value it's not important.

Inner join vs Where

No! The same execution plan, look at these two tables:

  id INT,
  name VARCHAR(20)

  id INT,
  name VARCHAR(20)

The execution plan for the query using the inner join:

-- with inner join

SELECT * FROM table1 t1
INNER JOIN table2 t2 ON =;


-- 0 select statement
-- 1 hash join (access("T1"."ID"="T2"."ID"))
-- 2 table access full table1
-- 3 table access full table2

And the execution plan for the query using a WHERE clause.

-- with where clause

SELECT * FROM table1 t1, table2 t2


-- 0 select statement
-- 1 hash join (access("T1"."ID"="T2"."ID"))
-- 2 table access full table1
-- 3 table access full table2

JDK on OSX 10.7 Lion

You can download the 10.7 Lion JDK from

  1. Sign in and click the java section on the right.

  2. The jdk is installed into a different location then previous. This will result in IDEs (such as Eclipse) being unable to locate source code and javadocs.

  3. At the time of writing the JDK ended up here:


  4. Open up eclipse preferences and go to Java --> Installed JREs page

  5. Rather than use the "JVM Contents (MacOS X Default) we will need to use the JDK location

  6. At the time of writing Search is not aware of the new JDK location; we we will need to click on the Add button

  7. From the Add JRE wizard choose "MacOS X VM" for the JRE Type

  8. For the JRE Definition Page we need to fill in the following:

    • JRE Home: /Library/Java/JavaVirtualMachines/1.6.0_26-b03-383.jdk/Contents/Home
  9. The other fields will now auto fill, with the default JRE name being "Home". You can quickly correct this to something more meaningful:

    • JRE name: System JDK
  10. Finish the wizard and return to the Installed JREs page

  11. Choose "System JDK" from the list

  12. You can now develop normally with:

    • javadocs correctly shown for base classes
    • source code correctly shown when debugging

Multiple Errors Installing Visual Studio 2015 Community Edition

Like the rest of you, I've spent days trying to figure this out. I've been down this thread trying every combination of what you have all said, and nothing. I finally went to AppData/Local/Microsoft/VisualStudio and deleted all the folders in there. Then proceeded to turn off everything in my Anti virus and I finally got the basic installation to go all the way through. Frustrating, but hopefully this will help someone else who has tried everything.

Increase number of axis ticks

You can supply a function argument to scale, and ggplot will use that function to calculate the tick locations.

dat <- data.frame(x = rnorm(100), y = rnorm(100))
number_ticks <- function(n) {function(limits) pretty(limits, n)}

ggplot(dat, aes(x,y)) +
  geom_point() +
  scale_x_continuous(breaks=number_ticks(10)) +

iPhone App Icons - Exact Radius?

I see a lot of "px" discussion but no one is talking percentages which is the fixed number you want to calculate by.

22.37% is the key percentage here. Multiply any of the image sizes mentioned above in by 0.2237 and you will get the correct pixel radius for that size.

Before iOS 8, Apple used less rounding, using 15.625%.

EDIT: Thanks @Chris Prince for commenting with the iOS 8/9/10 radius percentage: 22.37%

Best way to store a key=>value array in JavaScript?

I know its late but it might be helpful for those that want other ways. Another way array key=>values can be stored is by using an array method called map(); ( you can use arrow function too

    var countries = ['Canada','Us','France','Italy'];  
// Arrow Function, key) => key+ ' : ' + value );
// Anonomous Function, key){
return key + " : " + value;

How can I capture the result of var_dump to a string?

function return_var_dump(){
    // It works like var_dump, but it returns a string instead of printing it.
    $args = func_get_args(); // For <5.3.0 support ...
    call_user_func_array('var_dump', $args);
    return ob_get_clean();

Run a PostgreSQL .sql file using command line arguments

you could even do it in this way:

sudo -u postgres psql -d myDataBase -a -f myInsertFile

If you have sudo access on machine and it's not recommended for production scripts just for test on your own machine it's the easiest way.

python paramiko ssh

There is something wrong with the accepted answer, it sometimes (randomly) brings a clipped response from server. I do not know why, I did not investigate the faulty cause of the accepted answer because this code worked perfectly for me:

import paramiko

ip='server ip'

cmd='some useful command' 



stdin,stdout,stderr=ssh.exec_command('some really useful command')

How to implement a Keyword Search in MySQL?

You can find another simpler option in a thread here: Match Against.. with a more detail help in 11.9.2. Boolean Full-Text Searches

This is just in case someone need a more compact option. This will require to create an Index FULLTEXT in the table, which can be accomplish easily.

Information on how to create Indexes (MySQL): MySQL FULLTEXT Indexing and Searching

In the FULLTEXT Index you can have more than one column listed, the result would be an SQL Statement with an index named search:

SELECT *,MATCH (`column`) AGAINST('+keyword1* +keyword2* +keyword3*') as relevance  FROM `documents`USE INDEX(search) WHERE MATCH (`column`) AGAINST('+keyword1* +keyword2* +keyword3*' IN BOOLEAN MODE) ORDER BY relevance;

I tried with multiple columns, with no luck. Even though multiple columns are allowed in indexes, you still need an index for each column to use with Match/Against Statement.

Depending in your criterias you can use either options.

Joining Spark dataframes on the key

Let me explain with an example

  1. create emp DataFrame

    import spark.sqlContext.implicits._ val emp = Seq((1,"Smith",-1,"2018","10","M",3000), (2,"Rose",1,"2010","20","M",4000), (3,"Williams",1,"2010","10","M",1000), (4,"Jones",2,"2005","10","F",2000), (5,"Brown",2,"2010","40","",-1), (6,"Brown",2,"2010","50","",-1) ) val empColumns = Seq("emp_id","name","superior_emp_id","year_joined", "emp_dept_id","gender","salary")

    val empDF = emp.toDF(empColumns:_*)

  2. Create dept DataFrame

    val dept = Seq(("Finance",10), ("Marketing",20), ("Sales",30), ("IT",40) )

    val deptColumns = Seq("dept_name","dept_id") val deptDF = dept.toDF(deptColumns:_*)

Now let's join emp.emp_dept_id with dept.dept_id

empDF.join(deptDF,empDF("emp_dept_id") ===  deptDF("dept_id"),"inner")

This results below

|emp_id|name    |superior_emp_id|year_joined|emp_dept_id|gender|salary|dept_name|dept_id|
|1     |Smith   |-1             |2018       |10         |M     |3000  |Finance  |10     |
|2     |Rose    |1              |2010       |20         |M     |4000  |Marketing|20     |
|3     |Williams|1              |2010       |10         |M     |1000  |Finance  |10     |
|4     |Jones   |2              |2005       |10         |F     |2000  |Finance  |10     |
|5     |Brown   |2              |2010       |40         |      |-1    |IT       |40     |

If you are looking in python PySpark Join with example and also find the complete Scala example at Spark Join

pandas resample documentation

There's more to it than this, but you're probably looking for this list:

B   business day frequency
C   custom business day frequency (experimental)
D   calendar day frequency
W   weekly frequency
M   month end frequency
BM  business month end frequency
MS  month start frequency
BMS business month start frequency
Q   quarter end frequency
BQ  business quarter endfrequency
QS  quarter start frequency
BQS business quarter start frequency
A   year end frequency
BA  business year end frequency
AS  year start frequency
BAS business year start frequency
H   hourly frequency
T   minutely frequency
S   secondly frequency
L   milliseconds
U   microseconds


Android Studio - ADB Error - "...device unauthorized. Please check the confirmation dialog on your device."

Please check this.

I faced the same issue. Could notice that the "adb integration" was disabled. Please enable it at your IDE (Tools | Android)

How to set Internet options for Android emulator?

I've seen various suggestions how code can find out whether it runs on the emulator, but none are quite satisfactory, or "future-proof". For the time being I've settled on reading the device ID, which is all zeros for the emulator:

TelephonyManager telmgr = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE); boolean isEmulator = "000000000000000".equals(telmgr.getDeviceId());

But on a deployed app that requires the READ_PHONE_STATE permission

What datatype should be used for storing phone numbers in SQL Server 2005?

Use CHAR(10) if you are storing US Phone numbers only. Remove everything but the digits.

Entity Framework Timeouts

If you are using Entity Framework like me, you should define Time out on Startup class as follows:

 services.AddDbContext<ApplicationDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection"), o => o.CommandTimeout(180)));

Bootstrap 3 Align Text To Bottom of Div

I collected some ideas from other SO question (largely from here and this css page)


The idea is to use relative and absolute positioning to move your line to the bottom:

@media (min-width: 768px ) {
.row {
    position: relative;

#bottom-align-text {
    position: absolute;
    bottom: 0;
    right: 0;

The display:flex option is at the moment a solution to make the div get the same size as its parent. This breaks on the other hand the bootstrap possibilities to auto-linebreak on small devices by adding col-sx-12 class. (This is why the media query is needed)

Content is not allowed in Prolog SAXParserException

This error can come if there is validation error either in your wsdl or xsd file. For instance I too got the same issue while running wsdl2java to convert my wsdl file to generate the client. In one of my xsd it was defined as below

<xs:import schemaLocation="" namespace="http://MultiChoice.PaymentService/DataContracts" />

Where the schemaLocation was empty. By providing the proper data in schemaLocation resolved my problem.

<xs:import schemaLocation="multichoice.paymentservice.DataContracts.xsd" namespace="http://MultiChoice.PaymentService/DataContracts" />

Comparing two java.util.Dates to see if they are in the same day

Convert dates to Java 8 java.time.LocalDate as seen here.

LocalDate localDate1 = date1.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
LocalDate localDate2 = date2.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();

// compare dates
assertTrue("Not on the same day", localDate1.equals(localDate2));

Setting PATH environment variable in OSX permanently

For a new path to be added to PATH environment variable in MacOS just create a new file under /etc/paths.d directory and add write path to be set in the file. Restart the terminal. You can check with echo $PATH at the prompt to confirm if the path was added to the environment variable.

For example: to add a new path /usr/local/sbin to the PATH variable:

cd /etc/paths.d
sudo vi newfile

Add the path to the newfile and save it.

Restart the terminal and type echo $PATH to confirm

Missing Microsoft RDLC Report Designer in Visual Studio

Update: The way RDLC Report Designer is installed has changed with Visual Studio 2017 and newer. See other answers for details. Besides that, the ReportViewer Control is now available through NuGet, see here.

original answer below

The Report Designer is part of the Microsoft SQL Server Data Tools.

You can add it using the Visual Studio setup (Programs and Features > Visual Studio 2015 > Change)


Stylesheet not updating

If it is cached on the server, there is nothing you can do in the browser to fix this. You have to wait for the server to reload the file. You can't even delete the file and re-upload it. This could take even longer if you are using a caching server like Cloudflare (it will even survive a server reboot). You could rename it and load a copy.

see if two files have the same content in python

I'm not sure if you want to find duplicate files or just compare two single files. If the latter, the above approach (filecmp) is better, if the former, the following approach is better.

There are lots of duplicate files detection questions here. Assuming they are not very small and that performance is important, you can

  • Compare file sizes first, discarding all which doesn't match
  • If file sizes match, compare using the biggest hash you can handle, hashing chunks of files to avoid reading the whole big file

Here's is an answer with Python implementations (I prefer the one by nosklo, BTW)

Convert image from PIL to openCV format

The code commented works as well, just choose which do you prefer

import numpy as np
from PIL import Image

def convert_from_cv2_to_image(img: np.ndarray) -> Image:
    # return Image.fromarray(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))
    return Image.fromarray(img)

def convert_from_image_to_cv2(img: Image) -> np.ndarray:
    # return cv2.cvtColor(numpy.array(img), cv2.COLOR_RGB2BGR)
    return np.asarray(img)

How can I get table names from an MS Access Database?

Schema information which is designed to be very close to that of the SQL-92 INFORMATION_SCHEMA may be obtained for the Jet/ACE engine (which is what I assume you mean by 'access') via the OLE DB providers.


OpenSchema Method (ADO)

Supported Schema Rowsets

Finding a branch point with Git?

Given that so many of the answers in this thread do not give the answer the question was asking for, here is a summary of the results of each solution, along with the script I used to replicate the repository given in the question.

The log

Creating a repository with the structure given, we get the git log of:

$ git --no-pager log --graph --oneline --all --decorate
* b80b645 (HEAD, branch_A) J - Work in branch_A branch
| *   3bd4054 (master) F - Merge branch_A into branch master
| |\  
| |/  
* |   a06711b I - Merge master into branch_A
|\ \  
* | | bcad6a3 H - Work in branch_A
| | * b46632a D - Work in branch master
| |/  
| *   413851d C - Merge branch_A into branch master
| |\  
| |/  
* | 6e343aa G - Work in branch_A
| * 89655bb B - Work in branch master
* 74c6405 (tag: branch_A_tag) A - Work in branch master
* 7a1c939 X - Work in branch master

My only addition, is the tag which makes it explicit about the point at which we created the branch and thus the commit we wish to find.

The solution which works

The only solution which works is the one provided by lindes correctly returns A:

$ diff -u <(git rev-list --first-parent branch_A) \
          <(git rev-list --first-parent master) | \
      sed -ne 's/^ //p' | head -1

As Charles Bailey points out though, this solution is very brittle.

If you branch_A into master and then merge master into branch_A without intervening commits then lindes' solution only gives you the most recent first divergance.

That means that for my workflow, I think I'm going to have to stick with tagging the branch point of long running branches, since I can't guarantee that they can be reliably be found later.

This really all boils down to gits lack of what hg calls named branches. The blogger jhw calls these lineages vs. families in his article Why I Like Mercurial More Than Git and his follow-up article More On Mercurial vs. Git (with Graphs!). I would recommend people read them to see why some mercurial converts miss not having named branches in git.

The solutions which don't work

The solution provided by mipadi returns two answers, I and C:

$ git rev-list --boundary branch_A...master | grep ^- | cut -c2-

The solution provided by Greg Hewgill return I

$ git merge-base master branch_A
$ git merge-base --all master branch_A

The solution provided by Karl returns X:

$ diff -u <(git log --pretty=oneline branch_A) \
          <(git log --pretty=oneline master) | \
       tail -1 | cut -c 2-42

The script

mkdir $1
cd $1
git init
git commit --allow-empty -m "X - Work in branch master"
git commit --allow-empty -m "A - Work in branch master"
git branch branch_A
git tag branch_A_tag     -m "Tag branch point of branch_A"
git commit --allow-empty -m "B - Work in branch master"
git checkout branch_A
git commit --allow-empty -m "G - Work in branch_A"
git checkout master
git merge branch_A       -m "C - Merge branch_A into branch master"
git checkout branch_A
git commit --allow-empty -m "H - Work in branch_A"
git merge master         -m "I - Merge master into branch_A"
git checkout master
git commit --allow-empty -m "D - Work in branch master"
git merge branch_A       -m "F - Merge branch_A into branch master"
git checkout branch_A
git commit --allow-empty -m "J - Work in branch_A branch"

I doubt the git version makes much difference to this, but:

$ git --version
git version 1.7.1

Thanks to Charles Bailey for showing me a more compact way to script the example repository.

WPF chart controls

aM Charts are also making WPF Chart controls. Currently they only show off a pie chart, but they are set to provide new ones in short term.

How can I delete using INNER JOIN with SQL Server?

It should be:

DELETE zpost 
FROM zpost 
INNER JOIN zcomment ON (zpost.zpostid = zcomment.zpostid)
WHERE zcomment.icomment = "first"       

jquery change class name

$('.btn').click(function() {


$('.btn').click(function() {

Webdriver findElements By xpath

Your questions:

Q 1.) I would like to know why it returns all the texts that following the div?
It should not and I think in will not. It returns all div with 'id' attribute value equal 'containter' (and all children of this). But you are printing the results with ele.getText() Where getText will return all text content of all children of your result.

Get the visible (i.e. not hidden by CSS) innerText of this element, including sub-elements, without any leading or trailing whitespace.
The innerText of this element.

Q 2.) how should I modify the code so it just return first or first few nodes that follow the parent note
This is not really clear what you are looking for. Example:

<p1> <div/> </p1 <p2/> 

The following to parent of the div is p2. This would be:


or shorter


If you are only looking for the first one extent the expression with an "predicate" (e.g [1] - for the first one. or [position() &lt; 4]for the first three)

If your are looking for the first child of the first div:


If there is only one div with id an you are looking for the first child:


and so on.

Javascript - check array for value

Try this:

// this will fix old browsers
if (!Array.prototype.indexOf) {
  Array.prototype.indexOf = function(value) {
    for (var i = 0; i < this.length; i++) {
      if (this[i] === value) {
        return i;

    return -1;

// example
if ([1, 2, 3].indexOf(2) != -1) {
  // yay!

Import MySQL database into a MS SQL Server

If you do an export with PhpMyAdmin, you can switch sql compatibility mode to 'MSSQL'. That way you just run the exported script against your MS SQL database and you're done.

If you cannot or don't want to use PhpMyAdmin, there's also a compatibility option in mysqldump, but personally I'd rather have PhpMyAdmin do it for me.

'module' object has no attribute 'DataFrame'

For me he problem was that my script was called in the folder pandas which obviously messed up my imports.

How to parse a date?

The problem is that you have a date formatted like this:

Thu Jun 18 20:56:02 EDT 2009

But are using a SimpleDateFormat that is:


The two formats don't agree. You need to construct a SimpleDateFormat that matches the layout of the string you're trying to parse into a Date. Lining things up to make it easy to see, you want a SimpleDateFormat like this:

EEE MMM dd HH:mm:ss zzz yyyy
Thu Jun 18 20:56:02 EDT 2009

Check the JavaDoc page I linked to and see how the characters are used.

Can't install APK from browser downloads

I had this problem. Couldn't install apk via the Downloads app. However opening the apk in a file manager app allowed me to install it fine. Using OI File Manager on stock Nexus 7 4.2.1

Difference between StringBuilder and StringBuffer

Difference between StringBuffer and StringBuilder Source:

enter image description here

Filter Linq EXCEPT on properties

ColinE's answer is simple and elegant. If your lists are larger and provided that the excluded apps list is sorted, BinarySearch<T> may prove faster than Contains.


unfilteredApps.Where(i => excludedAppIds.BinarySearch(i.Id) < 0);

How do you connect to a MySQL database using Oracle SQL Developer?

Here's another extremely detailed walkthrough that also shows you the entire process, including what values to put in the connection dialogue after the JDBC driver is installed:

How to execute multiple SQL statements from java

I'm not sure that you want to send two SELECT statements in one request statement because you may not be able to access both ResultSets. The database may only return the last result set.

Multiple ResultSets

However, if you're calling a stored procedure that you know can return multiple resultsets something like this will work

CallableStatement stmt = con.prepareCall(...);
try {

boolean results = stmt.execute();

while (results) {
    ResultSet rs = stmt.getResultSet();
    try {
    while ( {
        // read the data
    } finally {
        try { rs.close(); } catch (Throwable ignore) {}

    // are there anymore result sets?
    results = stmt.getMoreResults();
} finally {
    try { stmt.close(); } catch (Throwable ignore) {}

Multiple SQL Statements

If you're talking about multiple SQL statements and only one SELECT then your database should be able to support the one String of SQL. For example I have used something like this on Sybase

StringBuffer sql = new StringBuffer( "SET rowcount 100" );
sql.append( " SELECT * FROM tbl_books ..." );
sql.append( " SET rowcount 0" );

stmt = conn.prepareStatement( sql.toString() );

This will depend on the syntax supported by your database. In this example note the addtional spaces padding the statements so that there is white space between the staments.

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

One of the reasons for this error is the use of the jaxb implementation from the jdk. I am not sure why such a problem can appear in pretty simple xml parsing situations. You may use the latest version of the jaxb library from a public maven repository:


How can I append a string to an existing field in MySQL?

You need to use the CONCAT() function in MySQL for string concatenation:

UPDATE categories SET code = CONCAT(code, '_standard') WHERE id = 1;

Can a JSON value contain a multiline string

I'm not sure of your exact requirement but one possible solution to improve 'readability' is to store it as an array.

  "testCases" :
    "case.1" :
      "scenario" : "this the case 1.",
      "result" : ["this is a very long line which is not easily readble.",
                  "so i would like to write it in multiple lines.",
                  "but, i do NOT require any new lines in the output."]


The join in back again whenever required with

result.join(" ")

if (boolean == false) vs. if (!boolean)

Apart from "readability", no. They're functionally equivalent.

("Readability" is in quotes because I hate == false and find ! much more readable. But others don't.)

How can I convert a zero-terminated byte array to string?

Simplistic solution:

str := fmt.Sprintf("%s", byteArray)

I'm not sure how performant this is though.

JAXB Exception: Class not known to this context

Your ProfileDto class is not referenced in SearchResultDto. Try adding @XmlSeeAlso(ProfileDto.class) to SearchResultDto.

ExpressionChangedAfterItHasBeenCheckedError Explained

Angular runs change detection and when it finds that some values which has been passed to the child component have been changed, Angular throws the following error:

ExpressionChangedAfterItHasBeenCheckedError click for more

In order to correct this we can use the AfterContentChecked life cycle hook and

import { ChangeDetectorRef, AfterContentChecked} from '@angular/core';

  private cdref: ChangeDetectorRef) { }

  ngAfterContentChecked() {



Passing 'this' to an onclick event

In JavaScript this always refers to the “owner” of the function we're executing, or rather, to the object that a function is a method of. When we define our faithful function doSomething() in a page, its owner is the page, or rather, the window object (or global object) of JavaScript.

How does the "this" keyword work?

How do the likely/unlikely macros in the Linux kernel work and what is their benefit?

These are macros that give hints to the compiler about which way a branch may go. The macros expand to GCC specific extensions, if they're available.

GCC uses these to to optimize for branch prediction. For example, if you have something like the following

if (unlikely(x)) {

return x;

Then it can restructure this code to be something more like:

if (!x) {
  return x;

return x;

The benefit of this is that when the processor takes a branch the first time, there is significant overhead, because it may have been speculatively loading and executing code further ahead. When it determines it will take the branch, then it has to invalidate that, and start at the branch target.

Most modern processors now have some sort of branch prediction, but that only assists when you've been through the branch before, and the branch is still in the branch prediction cache.

There are a number of other strategies that the compiler and processor can use in these scenarios. You can find more details on how branch predictors work at Wikipedia:

sys.path different in Jupyter and Python - how to import own modules in Jupyter?

You can use absolute imports:


# In the file.ipynb importing the file
from import config

Operation must use an updatable query. (Error 3073) Microsoft Access

Since Jet 4, all queries that have a join to a SQL statement that summarizes data will be non-updatable. You aren't using a JOIN, but the WHERE clause is exactly equivalent to a join, and thus, the Jet query optimizer treats it the same way it treats a join.

I'm afraid you're out of luck without a temp table, though maybe somebody with greater Jet SQL knowledge than I can come up with a workaround.

BTW, it might have been updatable in Jet 3.5 (Access 97), as a whole lot of queries were updatable then that became non-updatable when upgraded to Jet 4.


Using CRON jobs to visit url?

* * * * * wget --quiet --output-document=/dev/null

I find --quiet clearer than -q, and --output-document=/dev/null clearer than -O - > /dev/null

How to emulate GPS location in the Android Emulator?

In Mac, Linux or Cygwin:

echo 'geo fix -99.133333 19.43333 2202' | nc localhost 5554

That will put you in Mexico City. Change your longitude/latitude/altitude accordingly. That should be enough if you are not interested in nmea.

Javascript "Uncaught TypeError: object is not a function" associativity question

I was getting this same error and spent a day and a half trying to find a solution. Naomi's answer lead me to the solution I needed.

My input (type=button) had an attribute name that was identical to a function name that was being called by the onClick event. Once I changed the attribute name everything worked.

<input type="button" name="clearEmployer" onClick="clearEmployer();">

changed to:

<input type="button" name="clearEmployerBtn" onClick="clearEmployer();">

Convert string with comma to integer

You may also want to make sure that your code localizes correctly, or make sure the users are used to the "international" notation. For example, "1,112" actually means different numbers across different countries. In Germany it means the number a little over one, instead of one thousand and something.

Corresponding Wikipedia article is at It seems to be poorly written at this time though. For example as a Chinese I'm not sure where does these description about thousand separator in China come from.

How to write macro for Notepad++?

I just did this in v5.9.1. Just go to the Macro Menu, click "Start Recording", perform your 3 replace all commands, then stop recording. You can then select "Save Current Recorded Macro", and play it back as often as you like, and it will perform the replaces as you expect.

javac option to compile all java files under a given directory recursively

find . -name "*.java" -print | xargs javac 

Kinda brutal, but works like hell. (Use only on small programs, it's absolutely not efficient)

Is it necessary to use # for creating temp tables in SQL server?

The difference between this two tables ItemBack1 and #ItemBack1 is that the first on is persistent (permanent) where as the other is temporary.

Now if take a look at your question again

Is it necessary to Use # for creating temp table in sql server?

The answer is Yes, because without this preceding # the table will not be a temporary table, it will be independent of all sessions and scopes.

Spring MVC: Error 400 The request sent by the client was syntactically incorrect

Another possible cause is to have the wrong order of RequestMapping attributes. As spring doc says:

An @RequestMapping handler method can have a very flexible signatures. The supported method arguments and return values are described in the following section. Most arguments can be used in arbitrary order with the only exception of BindingResult arguments. This is described in the next section.

If you scroll down the doc, you will see that the BindingResult has to be immediatelly after the model attribute, since we can have multiple model objects per request and thus multiple bindings

The Errors or BindingResult parameters have to follow the model object that is being bound immediately as the method signature might have more than one model object and Spring will create a separate BindingResult instance for each of them so the following sample won’t work:

Here are two examples:

Invalid ordering of BindingResult and @ModelAttribute.

@RequestMapping(method = RequestMethod.POST) public String processSubmit(@ModelAttribute("pet") Pet pet, Model model, BindingResult result) { ... } Note, that there is a Model parameter in between Pet and BindingResult. To get this working you have to reorder the parameters as follows:

@RequestMapping(method = RequestMethod.POST) public String processSubmit(@ModelAttribute("pet") Pet pet, BindingResult result, Model model) { ... }

How to change maven java home

If you are dealing with multiple projects needing different Java versions to build, there is no need to set a new JAVA_HOME environment variable value for each build. Instead execute Maven like:

JAVA_HOME=/path/to/your/jdk mvn clean install

It will build using the specified JDK, but it won't change your environment variable.


$ mvn -v
Apache Maven 3.6.0
Maven home: /usr/share/maven
Java version: 11.0.6, vendor: Ubuntu, runtime: /usr/lib/jvm/java-11-openjdk-amd64
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "4.15.0-72-generic", arch: "amd64", family: "unix"

$ JAVA_HOME=/opt/jdk1.8.0_201 mvn -v
Apache Maven 3.6.0
Maven home: /usr/share/maven
Java version: 1.8.0_201, vendor: Oracle Corporation, runtime: /opt/jdk1.8.0_201/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "4.15.0-72-generic", arch: "amd64", family: "unix"

$ export | grep JAVA_HOME
declare -x JAVA_HOME="/usr/lib/jvm/java-11-openjdk-amd64"

Position DIV relative to another DIV?

you can use position:relative; inside #one div and position:absolute inside #two div. you can see it

Using other keys for the waitKey() function of opencv

The keycodes returned by waitKey seem platform dependent. However, it may be very educative, to see what the keys return (and by the way, on my platform, Esc does not return 27...)

The integers thay Abid's answer lists are mosty useless to the human mind (unless you're a prodigy savant...). However, if you examine them in hex, or take a look at the Least Significant Byte, you may notice patterns...

My script for examining the return values from waitKey is below:

#!/usr/bin/env python

import cv2
import sys

cv2.imshow(sys.argv[1], cv2.imread(sys.argv[1]))
res = cv2.waitKey(0)
print('You pressed %d (0x%x), LSB: %d (%s)' % (res, res, res % 256,
    repr(chr(res%256)) if res%256 < 128 else '?'))

You can use it as a minimal, command-line image viewer.

Some results, which I got:

  • q letter:

    You pressed 1048689 (0x100071), LSB: 113 ('q')

  • Escape key (traditionally, ASCII 27):

    You pressed 1048603 (0x10001b), LSB: 27 ('\x1b')

  • Space:

    You pressed 1048608 (0x100020), LSB: 32 (' ')

This list could go on, however you see the way to go, when you get 'strange' results.

BTW, if you want to put it in a loop, you can just waitKey(0) (wait forever), instead of ignoring the -1 return value.

EDIT: There's more to these high bits than meets the eye - please see Andrew C's answer (hint: it has to do with keyboard modifiers like all the "Locks" e.g. NumLock).

My recent experience shows however, that there is a platform dependence - e.g. OpenCV 4.1.0 from Anaconda on Python 3.6 on Windows doesn't produce these bits, and for some (important) keys is returns 0 from waitKey() (arrows, Home, End, PageDn, PageUp, even Del and Ins). At least Backspace returns 8 (but... why not Del?).

So, for a cross platform UI you're probably restricted to W, A, S, D, letters, digits, Esc, Space and Backspace ;)

Difference and uses of onCreate(), onCreateView() and onActivityCreated() in fragments

onActivityCreated() - Deprecated

onActivityCreated() is now deprecated as Fragments Version 1.3.0-alpha02

The onActivityCreated() method is now deprecated. Code touching the fragment's view should be done in onViewCreated() (which is called immediately before onActivityCreated()) and other initialization code should be in onCreate(). To receive a callback specifically when the activity's onCreate() is complete, a LifeCycleObserver should be registered on the activity's Lifecycle in onAttach(), and removed once the onCreate() callback is received.

Detailed information can be found here

How to set max width of an image in CSS

Given your container width 600px.

If you want only bigger images than that to fit inside, add: CSS:

#ImageContainer img {
    max-width: 600px;

If you want ALL images to take the avaiable (600px) space:

#ImageContainer img {
    width: 600px;

How do I make a simple makefile for gcc on Linux?

Depending on the number of headers and your development habits, you may want to investigate gccmakedep. This program examines your current directory and adds to the end of the makefile the header dependencies for each .c/cpp file. This is overkill when you have 2 headers and one program file. However, if you have 5+ little test programs and you are editing one of 10 headers, you can then trust make to rebuild exactly those programs which were changed by your modifications.

How do I set Tomcat Manager Application User Name and Password for NetBeans?

I case of tomcat 7 the role has changed from manager to manager-gui so set it as below in the tomcat-user.xml file.

enter image description here

how to convert a string to date in mysql?

The following illustrates the syntax of the STR_TO_DATE() function:


The STR_TO_DATE() converts the str string into a date value based on the fmt format string. The STR_TO_DATE() function may return a DATE , TIME, or DATETIME value based on the input and format strings. If the input string is illegal, the STR_TO_DATE() function returns NULL.

The following statement converts a string into a DATE value.

SELECT STR_TO_DATE('21,5,2013','%d,%m,%Y');

enter image description here

Based on the format string ‘%d, %m, %Y’, the STR_TO_DATE() function scans the ‘21,5,2013’ input string.

  • First, it attempts to find a match for the %d format specifier, which is a day of the month (01…31), in the input string. Because the number 21 matches with the %d specifier, the function takes 21 as the day value.
  • Second, because the comma (,) literal character in the format string matches with the comma in the input string, the function continues to check the second format specifier %m , which is a month (01…12), and finds that the number 5 matches with the %m format specifier. It takes the number 5 as the month value.
  • Third, after matching the second comma (,), the STR_TO_DATE() function keeps finding a match for the third format specifier %Y , which is four-digit year e.g., 2012,2013, etc., and it takes the number 2013 as the year value.

The STR_TO_DATE() function ignores extra characters at the end of the input string when it parses the input string based on the format string. See the following example:

SELECT STR_TO_DATE('21,5,2013 extra characters','%d,%m,%Y');

enter image description here

More Details : Reference

Java array reflection: isArray vs. instanceof

There is no difference in behavior that I can find between the two (other than the obvious null-case). As for which version to prefer, I would go with the second. It is the standard way of doing this in Java.

If it confuses readers of your code (because String[] instanceof Object[] is true), you may want to use the first to be more explicit if code reviewers keep asking about it.

How to check whether a file is empty or not?

import os    
os.path.getsize(fullpathhere) > 0

Create a batch file to copy and rename file

type C:\temp\test.bat>C:\temp\test.log

Detecting input change in jQuery?

There are jQuery events like keyup and keypress which you can use with input HTML Elements. You could additionally use the blur() event.

Constantly print Subprocess output while process is running


tried your code and corrected it for 3.4 and windows dir.cmd is a simple dir command, saved as cmd-file

import subprocess
c = "dir.cmd"

def execute(command):
    popen = subprocess.Popen(command, stdout=subprocess.PIPE,bufsize=1)
    lines_iterator = iter(popen.stdout.readline, b"")
    while popen.poll() is None:
        for line in lines_iterator:
            nline = line.rstrip()
            print(nline.decode("latin"), end = "\r\n",flush =True) # yield line


How to get first object out from List<Object> using Linq

Try this to get all the list at first, then your desired element (say the First in your case):

var desiredElementCompoundValueList = new List<YourType>();
dic.Values.ToList().ForEach( elem => 
var x = desiredElementCompoundValueList.FirstOrDefault();

To get directly the first element value without a lot of foreach iteration and variable assignment:

var desiredCompoundValue = dic.Values.ToList().Select( elem => elem.CompoundValue("Dep")).FirstOrDefault();

See the difference between the two approaches: in the first one you get the list through a ForEach, then your element. In the second you can get your value in a straight way.

Same result, different computation ;)

Using Jquery Ajax to retrieve data from Mysql

For retrieving data using Ajax + jQuery, you should write the following code:

 <script type="text/javascript" src="jquery-1.3.2.js"> </script>

 <script type="text/javascript">

 $(document).ready(function() {

    $("#display").click(function() {                

      $.ajax({    //create an ajax request to display.php
        type: "GET",
        url: "display.php",             
        dataType: "html",   //expect html to be returned                
        success: function(response){                    



<h3 align="center">Manage Student Details</h3>
<table border="1" align="center">
       <td> <input type="button" id="display" value="Display All Data" /> </td>
<div id="responsecontainer" align="center">


For mysqli connection, write this:


For displaying the data from database, you should write this :

$result=mysqli_query("select * from student",$con);

echo "<table border='1' >
<td align=center> <b>Roll No</b></td>
<td align=center><b>Name</b></td>
<td align=center><b>Address</b></td>
<td align=center><b>Stream</b></td></td>
<td align=center><b>Status</b></td>";

while($data = mysqli_fetch_row($result))
    echo "<tr>";
    echo "<td align=center>$data[0]</td>";
    echo "<td align=center>$data[1]</td>";
    echo "<td align=center>$data[2]</td>";
    echo "<td align=center>$data[3]</td>";
    echo "<td align=center>$data[4]</td>";
    echo "</tr>";
echo "</table>";

How to determine equality for two JavaScript objects?

I'd advise against hashing or serialization (as the JSON solution suggest). If you need to test if two objects are equal, then you need to define what equals means. It could be that all data members in both objects match, or it could be that must the memory locations match (meaning both variables reference the same object in memory), or may be that only one data member in each object must match.

Recently I developed an object whose constructor creates a new id (starting from 1 and incrementing by 1) each time an instance is created. This object has an isEqual function that compares that id value with the id value of another object and returns true if they match.

In that case I defined "equal" as meaning the the id values match. Given that each instance has a unique id this could be used to enforce the idea that matching objects also occupy the same memory location. Although that is not necessary.

javascript scroll event for iPhone/iPad?

The iPhoneOS does capture onscroll events, except not the way you may expect.

One-finger panning doesn’t generate any events until the user stops panning—an onscroll event is generated when the page stops moving and redraws—as shown in Figure 6-1.

Similarly, scroll with 2 fingers fires onscroll only after you've stopped scrolling.

The usual way of installing the handler works e.g.

window.addEventListener('scroll', function() { alert("Scrolled"); });
// or
$(window).scroll(function() { alert("Scrolled"); });
// or
window.onscroll = function() { alert("Scrolled"); };
// etc 

(See also

What is the main difference between Inheritance and Polymorphism?

Polymorphism is an effect of inheritance. It can only happen in classes that extend one another. It allows you to call methods of a class without knowing the exact type of the class. Also, polymorphism does happen at run time.

For example, Java polymorphism example:

enter image description here

Inheritance lets derived classes share interfaces and code of their base classes. It happens at compile time.

For example, All Classes in the Java Platform are Descendants of Object (image courtesy Oracle):

enter image description here

To learn more about Java inheritance and Java polymorphism

Non-resolvable parent POM for Could not find artifact and 'parent.relativePath' points at wrong local POM

I encountered an issue like this using the Maven Release Plugin. Resolving using relative paths (i.e. for the parent pom in the child module ../parent/pom.xml) did not seem to work in this scenario, it keeps looking for the released parent pom in the Nexus repository. Moving the parent pom to the parent folder of the module resolved this.

How to save a Seaborn plot into a file

The suggested solutions are incompatible with Seaborn 0.8.1

giving the following errors because the Seaborn interface has changed:

AttributeError: 'AxesSubplot' object has no attribute 'fig'
When trying to access the figure

AttributeError: 'AxesSubplot' object has no attribute 'savefig'
when trying to use the savefig directly as a function

The following calls allow you to access the figure (Seaborn 0.8.1 compatible):

swarm_plot = sns.swarmplot(...)
fig = swarm_plot.get_figure()

as seen previously in this answer.

UPDATE: I have recently used PairGrid object from seaborn to generate a plot similar to the one in this example. In this case, since GridPlot is not a plot object like, for example, sns.swarmplot, it has no get_figure() function. It is possible to directly access the matplotlib figure by

fig = myGridPlotObject.fig

Like previously suggested in other posts in this thread.

BeautifulSoup Grab Visible Webpage Text

Try this:

from bs4 import BeautifulSoup
from bs4.element import Comment
import urllib.request

def tag_visible(element):
    if in ['style', 'script', 'head', 'title', 'meta', '[document]']:
        return False
    if isinstance(element, Comment):
        return False
    return True

def text_from_html(body):
    soup = BeautifulSoup(body, 'html.parser')
    texts = soup.findAll(text=True)
    visible_texts = filter(tag_visible, texts)  
    return u" ".join(t.strip() for t in visible_texts)

html = urllib.request.urlopen('').read()

How to remove MySQL root password

You need to set the password for root@localhost to be blank. There are two ways:

  1. The MySQL SET PASSWORD command:

    SET PASSWORD FOR root@localhost=PASSWORD('');
  2. Using the command-line mysqladmin tool:

    mysqladmin -u root -pType_in_your_current_password_here password ''

How to call loading function with React useEffect only once

If you only want to run the function given to useEffect after the initial render, you can give it an empty array as second argument.

function MyComponent() {
  useEffect(() => {
  }, []);

  return <div> {/* ... */} </div>;

Getting the index of the returned max or min item using max()/min() on a list

Just a minor addition to what has already been said. values.index(min(values)) seems to return the smallest index of min. The following gets the largest index:

    (values.index(min(values)) + len(values) - 1) % len(values)

The last line can be left out if the side effect of reversing in place does not matter.

To iterate through all occurrences

    indices = []
    i = -1
    for _ in range(values.count(min(values))):
      i = values[i + 1:].index(min(values)) + i + 1

For the sake of brevity. It is probably a better idea to cache min(values), values.count(min) outside the loop.

How to check if a particular service is running on Ubuntu

To check the status of a service on linux operating system :

//in case of super user(admin) requires    
sudo service {service_name} status 
// in case of normal user
service {service_name} status 

To stop or start service

// in case of admin requires
sudo service {service_name} start/stop
// in case of normal user
service {service_name} start/stop 

To get the list of all services along with PID :

sudo service --status-all

You can use systemctl instead of directly calling service :

systemctl status/start/stop {service_name}

Detecting IE11 using CSS Capability/Feature Detection

Detecting IE and its versions actually is extremely easy, at least extremely intuitive:

var uA = navigator.userAgent;
var browser = null;
var ieVersion = null;

if (uA.indexOf('MSIE 6') >= 0) {
    browser = 'IE';
    ieVersion = 6;
if (uA.indexOf('MSIE 7') >= 0) {
    browser = 'IE';
    ieVersion = 7;
if (document.documentMode) { // as of IE8
    browser = 'IE';
    ieVersion = document.documentMode;


This way, ou're also catching high IE versions in Compatibility Mode/View. Next, its a matter of assigning conditional classes:

var htmlTag = document.documentElement;
if (browser == 'IE' && ieVersion <= 11)
    htmlTag.className += ' ie11-';

Using $_POST to get select option value from HTML

<select name="taskOption">
      <option value="first">First</option>
      <option value="second">Second</option>
      <option value="third">Third</option>

$var = $_POST['taskOption'];

Angular Material: mat-select not selecting default

I did it just like in these examples. Tried to set the value of the mat-select to the value of one of the mat-options. But failed.

My mistake was to do [(value)]="someNumberVariable" to a numeric type variable while the ones in mat-options were strings. Even if they looked the same in the template it would not select that option.

Once I parsed the someNumberVariable to a string everything was totally fine.

So it seems you need to have the mat-select and the mat-option values not only be the same number (if you are presenting numbers) but also let them be of type string.

change image opacity using javascript

I'm not sure if you can do this in every browser but you can set the css property of the specified img.
Try to work with jQuery which allows you to make css changes much faster and efficiently.
in jQuery you will have the options of using .animate(),.fadeTo(),.fadeIn(),.hide("slow"),.show("slow") for example.
I mean this CSS snippet should do the work for you:

filter:alpha(opacity=40); /* For IE8 and earlier */

Also check out this website where everything further is explained:

Get record counts for all tables in MySQL database

     WHERE TABLE_SCHEMA = '{your_db}';

Note from the docs though: For InnoDB tables, the row count is only a rough estimate used in SQL optimization. You'll need to use COUNT(*) for exact counts (which is more expensive).

Convert timestamp to date in MySQL query

Convert timestamp to date in MYSQL

Make the table with an integer timestamp:

mysql> create table foo(id INT, mytimestamp INT(11));
Query OK, 0 rows affected (0.02 sec)

Insert some values

mysql> insert into foo values(1, 1381262848);
Query OK, 1 row affected (0.01 sec)

Take a look

mysql> select * from foo;
| id   | mytimestamp |
|    1 |  1381262848 |
1 row in set (0.00 sec)

Convert the number to a timestamp:

mysql> select id, from_unixtime(mytimestamp) from foo;
| id   | from_unixtime(mytimestamp) |
|    1 | 2013-10-08 16:07:28        |
1 row in set (0.00 sec)

Convert it into a readable format:

mysql> select id, from_unixtime(mytimestamp, '%Y %D %M %H:%i:%s') from foo;
| id   | from_unixtime(mytimestamp, '%Y %D %M %H:%i:%s') |
|    1 | 2013 8th October 04:07:28                       |
1 row in set (0.00 sec)

Working copy locked error in tortoise svn while committing

No problem... try this:

  • Go to top level SVN folder.
  • Right click on folder (that has your svn files) > TortoiseSVN > CleanUp

This will surely solve your problem. I did this lots of time... :)

Note. Make sure "Break locks" option is selected in the Cleanup dialog.

How to clear the JTextField by clicking JButton

Looking for EventHandling, ActionListener?

or code?

JButton b = new JButton("Clear");
b.addActionListener(new ActionListener(){
    public void actionPerformed(ActionEvent e){
        //textfield.setText(null); //or use this

Also See
How to Use Buttons

Batch file script to zip files

You're near :)

First, the batch (%%variable) and Windows CMD (%variable) uses different variable naming. Second, i dont figure out how do you use zip from CMD. This is from Linux users i think. Use built-in zip manipulation is not like easy on Win, and even harder with batch scripting.

But you're lucky anyway. I got (extracted to target folder) zip.exe and cygwin1.dll from the cygwin package (3mb filesize both together) and start play with it right now.

Of course, i use CMD for better/faster testing instead batch. Only remember modify the %varname to %%varname before blame me :P

for /d %d in (*) do zip -r %d %d

Explanation: for /d ... that matches any folder inside. Only folder ignoring files. (use for /f to filesmatch) for /d %d in ... the %d tells cmd wich name do you wanna assign to your variable. I put d to match widh d (directory meaning). for /d %d in (*) ... Very important. That suposses that I CD to desired folder, or run from. (*) this will mean all on THIS dir, because we use /d the files are not processed so no need to set a pattern, even if you can get only some folders if you need. You can use absolute paths. Not sure about issues with relatives from batch. for /d %d in (*) do zip -r ... Do ZIP is obvious. (exec zip itself and see the help display to use your custom rules). r- is for recursive, so anyting will be added. for /d %d in (*) do zip -r %d %d The first %d is the zip name. You can try with, but if will fail because if you have 2 or more folders the second cannot gave the name of the first and will not try to overwrite without more params. So, we pass %d to both, wich is the current for iteration folder name zipped into a file with the folder name. Is not neccesary to append ".zip" to name.

Is pretty short than i expected when start to play with.

Print all key/value pairs in a Java ConcurrentHashMap

The ConcurrentHashMap is very similar to the HashMap class, except that ConcurrentHashMap offers internally maintained concurrency. It means you do not need to have synchronized blocks when accessing ConcurrentHashMap in multithreaded application.

To get all key-value pairs in ConcurrentHashMap, below code which is similar to your code works perfectly:

//Initialize ConcurrentHashMap instance
ConcurrentHashMap<String, Integer> m = new ConcurrentHashMap<String, Integer>();

//Print all values stored in ConcurrentHashMap instance
for each (Entry<String, Integer> e : m.entrySet()) {

Above code is reasonably valid in multi-threaded environment in your application. The reason, I am saying 'reasonably valid' is that, above code yet provides thread safety, still it can decrease the performance of application.

Hope this helps you.

Check variable equality against a list of values

For posterity you might want to use regular expressions as an alternative. Pretty good browser support as well (ref.

Try this

if (foo.toString().match(/^(1|3|12)$/)) {
    document.write('Regex me IN<br>');
} else {
    document.write('Regex me OUT<br>');

CSS: How to align vertically a "label" and "input" inside a "div"?

div {_x000D_
    display: table-cell;_x000D_
    vertical-align: middle;_x000D_
    height: 50px;_x000D_
    border: 1px solid red;_x000D_
    <label for='name'>Name:</label>_x000D_
    <input type='text' id='name' />_x000D_

The advantages of this method is that you can change the height of the div, change the height of the text field and change the font size and everything will always stay in the middle.

How do I set ANDROID_SDK_HOME environment variable?

If you face the same error, here are the step by step instructions:

  1. Open control panel
  2. Then go to System
  3. Then go to Change Environment Variables of the User
  4. Then click create a new environment variables
  5. Create a new variable named ANDROID_SDK_HOME
  6. Set its value to your Android directory, like C:/users/<username>/.android

How can I increase a scrollbar's width using CSS?


If the scrollbar is not the browser scrollbar, then it will be built of regular HTML elements (probably divs and spans) and can thus be styled (or will be Flash, Java, etc and can be customized as per those environments).

The specifics depend on the DOM structure used.

Graphical HTTP client for windows

Have you looked at Fiddler 2 from Microsoft?

Allows you to generate most types of request for testing, including POST. It also supports capturing HTTP requests made by other applications and reusing those for testing.

Android widget: How to change the text of a button

//text button:

        android:text=" text button" />

// color text button:

        android:text="text button" 
        android:textColor="@android:color/color text"/>

// background button

        android:text="text button" 
        android:background="@android:color/ background button"/>

// text size button

        android:text="text button" 
        android:textSize="text size"/>

What is the difference between jQuery: text() and html() ?

I think that the difference is to insert html tag in text() you html tag do not functions

$('#output').html('You are registered'+'<br>'  +'  '
                     + 'Mister'+'  ' + name+'   ' + sourname ); }

output :

You are registered <br> Mister name sourname

replacing text() with html()


You are registered
Mister name sourname 

then the tag <br> works in html()

Warn user before leaving web page with unsaved changes

The following one-liner has worked for me.

window.onbeforeunload = s => modified ? "" : null;

Just set modified to true or false depending on the state of your application.

jQuery override default validation error message display (Css) Popup/Tooltip like

Unfortunately I can't comment with my newbie reputation, but I have a solution for the issue of the screen going blank, or at least this is what worked for me. Instead of setting the wrapper class inside of the errorPlacement function, set it immediately when you're setting the wrapper type.

    errorElement: "div",
    wrapper: "div class=\"message\"",
    errorPlacement: function(error, element) {
        offset = element.offset();
        //error.addClass('message');  // add a class to the wrapper
        error.css('position', 'absolute');
        error.css('left', offset.left + element.outerWidth() + 5);
        error.css('top', - 3);


I'm assuming doing it this way allows the validator to know which div elements to remove, instead of all of them. Worked for me but I'm not entirely sure why, so if someone could elaborate that might help others out a ton.

Where can I get a list of Countries, States and Cities?

This may be a sideways answer, but if you download Virtuemart (A Joomla component), it has a countries table and all the related states all set up for you included in the installation SQL. They're called jos_virtuemart_countries and jos_virtuemart_states. It also includes the 2 and 3 character country codes. I'd attach it to my answer, but don't see a way of doing it.

Prevent browser caching of AJAX call result

A small addition to the excellent answers given: If you're running with a non-ajax backup solution for users without javascript, you will have to get those server-side headers correct anyway. This is not impossible, although I understand those that give it up ;)

I'm sure there's another question on SO that will give you the full set of headers that are appropriate. I am not entirely conviced miceus reply covers all the bases 100%.

Refresh (reload) a page once using jQuery?

To reload, you can try this:


How to change font size in html?

Give them a class and add your style to the class.

  p {
    color: red;
  .paragraph1 {
    font-size: 18px;
  .paragraph2 {
    font-size: 13px;

<p class="paragraph1">Paragraph 1</p>
<p class="paragraph2">Paragraph 2</p>

Check this EXAMPLE

Uncaught TypeError: data.push is not a function

make sure you push into an Array only and if their is error like Uncaught TypeError: data.push is not a function** then check for type of data you can do this by consol.log(data) hope this will help

Angular no provider for NameService

Hi , You can use this in your .ts file :

first import your service in this .ts file:

import { Your_Service_Name } from './path_To_Your_Service_Name';

Then in the same file you can add providers: [Your_Service_Name] :

      selector: 'my-app',
      providers: [Your_Service_Name],
      template: `
        <h1>Hello World</h1> `   

Python threading. How do I lock a thread?

import threading 

# global variable x 
x = 0

def increment(): 
    function to increment global variable x 
    global x 
    x += 1

def thread_task(): 
    task for thread 
    calls increment function 100000 times. 
    for _ in range(100000): 

def main_task(): 
    global x 
    # setting global variable x as 0 
    x = 0

    # creating threads 
    t1 = threading.Thread(target=thread_task) 
    t2 = threading.Thread(target=thread_task) 

    # start threads 

    # wait until threads finish their job 

if __name__ == "__main__": 
    for i in range(10): 
        print("Iteration {0}: x = {1}".format(i,x))

How can I switch language in google play?

Answer below the dotted line below is the original that's now outdated.

Here is the latest information ( Thank you @deadfish ):

add &hl=<language> like &hl=pl or &hl=en

example: or

All available languages and abbreviations can be looked up here:


To change the actual local market:

Basically the market is determined automatically based on your IP. You can change some local country settings from your Gmail account settings but still IP of the country you're browsing from is more important. To go around it you'd have to Proxy-cheat. Check out some ways/sites:

To do it from an Android phone you'd need to find an app. I don't have my Droid anymore but give this a try:

how to fix Cannot call sendRedirect() after the response has been committed?

you have already forwarded the response in catch block:

RequestDispatcher dd = request.getRequestDispatcher("error.jsp");

dd.forward(request, response);

so, you can not again call the :


because it is already forwarded (committed).

So what you can do is: keep a string to assign where you need to forward the response.

    String page = "";
    try {

    } catch (Exception e) {
      page = "error.jsp";
    } finally {
      page = "usertaskpage.jsp";

RequestDispatcher dd=request.getRequestDispatcher(page);
dd.forward(request, response);

Where do I configure log4j in a JUnit test class?

I generally just put a log4j.xml file into src/test/resources and let log4j find it by itself: no code required, the default log4j initialisation will pick it up. (I typically want to set my own loggers to 'DEBUG' anyway)

Add a string of text into an input field when user clicks a button

this will do it with just javascript - you can also put the function in a .js file and call it with onclick

<div onclick="
   document.forms['name_of_the_form']['name_of_the_input'].value += 'text you want to add to it'"

Get a list of resources from classpath directory

Used a combination of Rob's response.

final String resourceDir = "resourceDirectory/";
List<String> files = IOUtils.readLines(Thread.currentThread().getClass().getClassLoader().getResourceAsStream(resourceDir), Charsets.UTF_8);

for(String f : files){
  String data= IOUtils.toString(Thread.currentThread().getClass().getClassLoader().getResourceAsStream(resourceDir + f));
  ....process data

make an html svg object also a clickable link

Just don't use <object>. Here's a solution that worked for me with <a> and <svg> tags:

<a href="<your-link>" class="mr-5 p-1 border-2 border-transparent text-gray-400 rounded-full hover:text-white focus:outline-none focus:text-white focus:bg-red-700 transition duration-150 ease-in-out" aria-label="Notifications">
    <svg xmlns="" viewBox="0 0 24 24" width="30" 
    height="30"><path class="heroicon-ui" fill="#fff" d="M17 16a3 3 0 1 1-2.83 
    2H9.83a3 3 0 1 1-5.62-.1A3 3 0 0 1 5 12V4H3a1 1 0 1 1 0-2h3a1 1 0 0 1 1 
    1v1h14a1 1 0 0 1 .9 1.45l-4 8a1 1 0 0 1-.9.55H5a1 1 0 0 0 0 2h12zM7 12h9.38l3- 
   6H7v6zm0 8a1 1 0 1 0 0-2 1 1 0 0 0 0 2zm10 0a1 1 0 1 0 0-2 1 1 0 0 0 0 2z"/>

Echo newline in Bash prints literal \n

In the off chance that someone finds themselves beating their head against the wall trying to figure out why a coworker's script won't print newlines, look out for this ->

function GET_RECORDS()
   echo -e "starting\n the process";

echo $(GET_RECORDS);

As in the above, the actual running of the method may itself be wrapped in an echo which supersedes any echos that may be in the method itself. Obviously I watered this down for brevity, it was not so easy to spot!

You can then inform your comrades that a better way to execute functions would be like so:

function GET_RECORDS()
   echo -e "starting\n the process";


filter out multiple criteria using excel vba

I think (from experimenting - MSDN is unhelpful here) that there is no direct way of doing this. Setting Criteria1 to an Array is equivalent to using the tick boxes in the dropdown - as you say it will only filter a list based on items that match one of those in the array.

Interestingly, if you have the literal values "<>A" and "<>B" in the list and filter on these the macro recorder comes up with

Range.AutoFilter Field:=1, Criteria1:="=<>A", Operator:=xlOr, Criteria2:="=<>B"

which works. But if you then have the literal value "<>C" as well and you filter for all three (using tick boxes) while recording a macro, the macro recorder replicates precisely your code which then fails with an error. I guess I'd call that a bug - there are filters you can do using the UI which you can't do with VBA.

Anyway, back to your problem. It is possible to filter values not equal to some criteria, but only up to two values which doesn't work for you:

Range("$A$1:$A$9").AutoFilter Field:=1, Criteria1:="<>A", Criteria2:="<>B", Operator:=xlAnd

There are a couple of workarounds possible depending on the exact problem:

  1. Use a "helper column" with a formula in column B and then filter on that - e.g. =ISNUMBER(A2) or =NOT(A2="A", A2="B", A2="C") then filter on TRUE
  2. If you can't add a column, use autofilter with Criteria1:=">-65535" (or a suitable number lower than any you expect) which will filter out non-numeric values - assuming this is what you want
  3. Write a VBA sub to hide rows (not exactly the same as an autofilter but it may suffice depending on your needs).

For example:

Public Sub hideABCRows(rangeToFilter As Range)
  Dim oCurrentCell As Range
  On Error GoTo errHandler

  Application.ScreenUpdating = False
  For Each oCurrentCell In rangeToFilter.Cells
    If oCurrentCell.Value = "A" Or oCurrentCell.Value = "B" Or oCurrentCell.Value = "C" Then
      oCurrentCell.EntireRow.Hidden = True
    End If
  Next oCurrentCell

  Application.ScreenUpdating = True
  Exit Sub

    Application.ScreenUpdating = True
End Sub

How to add a set path only for that batch file executing?

Just like any other environment variable, with SET:

SET PATH=%PATH%;c:\whatever\else

If you want to have a little safety check built in first, check to see if the new path exists first:

IF EXIST c:\whatever\else SET PATH=%PATH%;c:\whatever\else

If you want that to be local to that batch file, use setlocal:

set PATH=...

@REM Rest of your script

Read the docs carefully for setlocal/endlocal , and have a look at the other references on that site - Functions is pretty interesting too and the syntax is tricky.

The Syntax page should get you started with the basics.

Why is it not advisable to have the database and web server on the same machine?

Operating system is another consideration. While your database may require larger memory spaces and therefore UNIX, your web server - or more specifically your app server since you mention only two tiers - may be a .Net-based, and therefore require Windows.

failed to open stream: No such file or directory in

you can use:

define("PATH_ROOT", dirname(__FILE__));
include_once PATH_ROOT . "/PoliticalForum/headerSite.php";

Using ResourceManager

There's surprisingly simple way of reading resource by string:


It's clean and elegant solution for reading resources by keys where "dot notation" cannot be used (for instance when resource key is persisted in the database).

Embed youtube videos that play in fullscreen automatically

This was pretty well answered over here: How to make a YouTube embedded video a full page width one?

If you add '?rel=0&autoplay=1' to the end of the url in the embed code (like this)

<iframe id="video" src="//" frameborder="0" allowfullscreen></iframe>

of the video it should play on load. Here's a demo over at jsfiddle.

Shortcut for changing font size

This worked for me:

Ctrl + - to minimize

Ctrl + + to maximize

Can the Android layout folder contain subfolders?

If you use the method in the approved answer, and want to improve it on a bit, then change the gradle setting like this:

    sourceSets {
    main {
        res.srcDirs = [

So if you add more folders and layouts, you don't need to come back here and append a long list of source folders, let gradle get all the folders for you.

Get city name using geolocation

You would do something like that using Google API.

Please note you must include the google maps library for this to work. Google geocoder returns a lot of address components so you must make an educated guess as to which one will have the city.

"administrative_area_level_1" is usually what you are looking for but sometimes locality is the city you are after.

Anyhow - more details on google response types can be found here and here.

Below is the code that should do the trick:

<!DOCTYPE html> 
<meta name="viewport" content="initial-scale=1.0, user-scalable=no"/> 
<meta http-equiv="content-type" content="text/html; charset=UTF-8"/> 
<title>Reverse Geocoding</title> 

<script type="text/javascript" src=""></script> 
<script type="text/javascript"> 
  var geocoder;

  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(successFunction, errorFunction);
//Get the latitude and the longitude;
function successFunction(position) {
    var lat = position.coords.latitude;
    var lng = position.coords.longitude;
    codeLatLng(lat, lng)

function errorFunction(){
    alert("Geocoder failed");

  function initialize() {
    geocoder = new google.maps.Geocoder();


  function codeLatLng(lat, lng) {

    var latlng = new google.maps.LatLng(lat, lng);
    geocoder.geocode({'latLng': latlng}, function(results, status) {
      if (status == google.maps.GeocoderStatus.OK) {
        if (results[1]) {
         //formatted address
        //find country name
             for (var i=0; i<results[0].address_components.length; i++) {
            for (var b=0;b<results[0].address_components[i].types.length;b++) {

            //there are different types that might hold a city admin_area_lvl_1 usually does in come cases looking for sublocality type will be more appropriate
                if (results[0].address_components[i].types[b] == "administrative_area_level_1") {
                    //this is the object you are looking for
                    city= results[0].address_components[i];
        //city data
        alert(city.short_name + " " + city.long_name)

        } else {
          alert("No results found");
      } else {
        alert("Geocoder failed due to: " + status);
<body onload="initialize()"> 


Open directory using C

Here is a simple way to implement ls command using c. To run use for example ./xls /tmp

    #include <dirent.h>
    void main(int argc,char *argv[])
   DIR *dir;
   struct dirent *dent;
   dir = opendir(argv[1]);   

        if((strcmp(dent->d_name,".")==0 || strcmp(dent->d_name,"..")==0 || (*dent->d_name) == '.' ))

CSS @media print issues with background-color;

To enable background printing in Chrome:

body {
  -webkit-print-color-adjust: exact !important;

How can I find which tables reference a given table in Oracle SQL Developer?

This has been in the product for years - although it wasn't in the product in 2011.

But, simply click on the Model page.

Make sure you are on at least version 4.0 (released in 2013) to access this feature.

enter image description here

Spark - repartition() vs coalesce()

Repartition: Shuffle the data into a NEW number of partitions.

Eg. Initial data frame is partitioned in 200 partitions.

df.repartition(500): Data will be shuffled from 200 partitions to new 500 partitions.

Coalesce: Shuffle the data into existing number of partitions.

df.coalesce(5): Data will be shuffled from remaining 195 partitions to 5 existing partitions.

Twig for loop for arrays with keys

I guess you want to do the "Iterating over Keys and Values"

As the doc here says, just add "|keys" in the variable you want and it will magically happen.

{% for key, user in users %}
    <li>{{ key }}: {{ user.username|e }}</li>
{% endfor %}

It never hurts to search before asking :)

How to create and add users to a group in Jenkins for authentication?

You could use Role Strategy plugin for that purpose. It works like a charm, just setup some roles and assign them. Even on project-specific level.

OCI runtime exec failed: exec failed: (...) executable file not found in $PATH": unknown

@papigee should work on Windows 10 just fine. I'm using the integrated VSCode terminal with git bash and this always works for me.

winpty docker exec -it <container-id> //bin//sh

Why does Git treat this text file as a binary file?

I was having this issue where Git GUI and SourceTree was treating Java/JS files as binary and thus wouldn’t show a diff.

Creating a file named attributes in .git/info with following content solved the problem:

*.java diff
*.js diff
*.pl diff
*.txt diff
*.ts diff
*.html diff
*.sh diff
*.xml diff

If you would like this to apply to all repositories, then you can add the file attributes in $HOME/.config/git/attributes.

How to do logging in React Native?

  1. Put console.log("My log text") in your code
  2. go to your command Line tools
  3. position oneself in its development folder

In Android:

  • write this command : React-native log-android


  • write this command : React-native log-ios

HTML select drop-down with an input field

You can use input text with "list" attribute, which refers to the datalist of values.

<input type="text" name="city" list="cityname">_x000D_
    <datalist id="cityname">_x000D_
      <option value="Boston">_x000D_
      <option value="Cambridge">_x000D_

This creates a free text input field that also has a drop-down to select predefined choices. Attribution for example and more information: