Programs & Examples On #Servletunit

Deleting records before a certain date

DELETE FROM table WHERE date < '2011-09-21 08:21:22';

Where is array's length property defined?

Arrays are special objects in java, they have a simple attribute named length which is final.

There is no "class definition" of an array (you can't find it in any .class file), they're a part of the language itself.

10.7. Array Members

The members of an array type are all of the following:

  • The public final field length, which contains the number of components of the array. length may be positive or zero.
  • The public method clone, which overrides the method of the same name in class Object and throws no checked exceptions. The return type of the clone method of an array type T[] is T[].

    A clone of a multidimensional array is shallow, which is to say that it creates only a single new array. Subarrays are shared.

  • All the members inherited from class Object; the only method of Object that is not inherited is its clone method.

Resources:

SQL Server database backup restore on lower version

I appreciate this is an old post, but it may be useful for people to know that the Azure Migration Wizard (available on Codeplex - can't link to is as Codeplex is at the moment I'm typing this) will do this easily.

Add a user control to a wpf window

Make sure there is an namespace definition (xmlns) for the namespace your control belong to.

xmlns:myControls="clr-namespace:YourCustomNamespace.Controls;assembly=YourAssemblyName"
<myControls:thecontrol/>

How to pass a file path which is in assets folder to File(String path)?

Unless you unpack them, assets remain inside the apk. Accordingly, there isn't a path you can feed into a File. The path you've given in your question will work with/in a WebView, but I think that's a special case for WebView.

You'll need to unpack the file or use it directly.

If you have a Context, you can use context.getAssets().open("myfoldername/myfilename"); to open an InputStream on the file. With the InputStream you can use it directly, or write it out somewhere (after which you can use it with File).

OVER_QUERY_LIMIT in Google Maps API v3: How do I pause/delay in Javascript to slow it down?

You are using setTimeout wrong way. The (one of) function signature is setTimeout(callback, delay). So you can easily specify what code should be run after what delay.

var codeAddress = (function() {
    var index = 0;
    var delay = 100;

    function GeocodeCallback(results, status) {
        if (status == google.maps.GeocoderStatus.OK) {
            map.setCenter(results[0].geometry.location);
            new google.maps.Marker({ map: map, position: results[0].geometry.location, animation: google.maps.Animation.DROP });
            console.log(results);
        }
        else alert("Geocode was not successful for the following reason: " + status);
    };

    return function(vPostCode) {
        if (geocoder) setTimeout(geocoder.geocode.bind(geocoder, { 'address': "'" + vPostCode + "'"}, GeocodeCallback), index*delay);
        index++;
    };
})();

This way, every codeAddress() call will result in geocoder.geocode() being called 100ms later after previous call.

I also added animation to marker so you will have a nice animation effect with markers being added to map one after another. I'm not sure what is the current google limit, so you may need to increase the value of delay variable.

Also, if you are each time geocoding the same addresses, you should instead save the results of geocode to your db and next time just use those (so you will save some traffic and your application will be a little bit quicker)

Is there a query language for JSON?

Sure, how about:

They all seem to be a bit work in progress, but work to some degree. They are also similar to XPath and XQuery conceptually; even though XML and JSON have different conceptual models (hierarchic vs object/struct).

EDIT Sep-2015: Actually there is now JSON Pointer standard that allows very simple and efficient traversal of JSON content. It is not only formally specified, but also supported by many JSON libraries. So I would call it actual real useful standard, although due to its limited expressiveness it may or may not be considered Query Language per se.

How to check radio button is checked using JQuery?

Taking some answers one step further - if you do the following you can check if any element within the radio group has been checked:

if ($('input[name="yourRadioNames"]:checked').val()){ (checked) or if (!$('input[name="yourRadioNames"]:checked').val()){ (not checked)

Create folder with batch but only if it doesn't already exist

You can use:

if not exist "C:\VTS\" mkdir "C:\VTS"

You can also expand the code to replace any missing expected files.

if not exist "C:\VTS\important.file" echo. > "C:\VTS\important.file"

Eclipse plugin for generating a class diagram

Try eUML2. its a single click generator no need to drag n drop.

Empty or Null value display in SSRS text boxes

I agree on performing the replace on the SQL side, but using the ISNULL function would be the way I'd go.

SELECT ISNULL(table.MyField, "NA") AS MyField

I usually do as much processing of data on our SQL servers and try to do as little data manipulation in SSRS as possible. This is mainly because my SQL server is considerably more powerful than my SSRS server.

How to redirect on another page and pass parameter in url from table?

Set the user name as data-username attribute to the button and also a class:

HTML

<input type="button" name="theButton" value="Detail" class="btn" data-username="{{result['username']}}" />

JS

$(document).on('click', '.btn', function() {

    var name = $(this).data('username');        
    if (name != undefined && name != null) {
        window.location = '/player_detail?username=' + name;
    }
});?

EDIT:

Also, you can simply check for undefined && null using:

$(document).on('click', '.btn', function() {

    var name = $(this).data('username');        
    if (name) {
        window.location = '/player_detail?username=' + name;
    }
});?

As, mentioned in this answer

if (name) {            
}

will evaluate to true if value is not:

  • null
  • undefined
  • NaN
  • empty string ("")
  • 0
  • false

The above list represents all possible falsy values in ECMA/Javascript.

How to check if a string array contains one string in JavaScript?

var stringArray = ["String1", "String2", "String3"];

return (stringArray.indexOf(searchStr) > -1)

Removing whitespace from strings in Java

You can do it so simply by

String newMysz = mysz.replace(" ","");

Hide Spinner in Input Number - Firefox 29

I mixed few answers from answers above and from How to remove the arrows from input[type="number"] in Opera in scss:

input[type=number] {
  &,
  &::-webkit-inner-spin-button,
  &::-webkit-outer-spin-button {
    -webkit-appearance: none;
    -moz-appearance: textfield;
    appearance: none;

    &:hover,
    &:focus {
      -moz-appearance: number-input;
    }
  }
}

Tested on chrome, firefox, safari

Angular 2 Unit Tests: Cannot find name 'describe'

Look at the import maybe you have a cycle dependency, this was in my case the error, using import {} from 'jasmine'; will fix the errors in the console and make the code compilable but not removes the root of devil (in my case the cycle dependency).

How do I make case-insensitive queries on Mongodb?

  1. With Mongoose (and Node), this worked:

    • User.find({ email: /^[email protected]$/i })

    • User.find({ email: new RegExp(`^${emailVariable}$`, 'i') })

  2. In MongoDB, this worked:

Both lines are case-insensitive. The email in the DB could be [email protected] and both lines will still find the object in the DB.

Likewise, we could use /^[email protected]$/i and it would still find email: [email protected] in the DB.

Is module __file__ attribute absolute or relative?

From the documentation:

__file__ is the pathname of the file from which the module was loaded, if it was loaded from a file. The __file__ attribute is not present for C modules that are statically linked into the interpreter; for extension modules loaded dynamically from a shared library, it is the pathname of the shared library file.

From the mailing list thread linked by @kindall in a comment to the question:

I haven't tried to repro this particular example, but the reason is that we don't want to have to call getpwd() on every import nor do we want to have some kind of in-process variable to cache the current directory. (getpwd() is relatively slow and can sometimes fail outright, and trying to cache it has a certain risk of being wrong.)

What we do instead, is code in site.py that walks over the elements of sys.path and turns them into absolute paths. However this code runs before '' is inserted in the front of sys.path, so that the initial value of sys.path is ''.

For the rest of this, consider sys.path not to include ''.

So, if you are outside the part of sys.path that contains the module, you'll get an absolute path. If you are inside the part of sys.path that contains the module, you'll get a relative path.

If you load a module in the current directory, and the current directory isn't in sys.path, you'll get an absolute path.

If you load a module in the current directory, and the current directory is in sys.path, you'll get a relative path.

My Routes are Returning a 404, How can I Fix Them?

Using WAMP click on wamp icon ->apache->apache modules->scroll and check rewrite_module Restart a LoadModule rewrite_module

Note, the server application restarts automatically for you once you enable "rewrite_module"

How to use BufferedReader in Java

As far as i understand fr is the object of your FileReadExample class. So it is obvious it will not have any method like fr.readLine() if you dont create one yourself.

secondly, i think a correct constructor of the BufferedReader class will help you do your task.

String str;
BufferedReader buffread = new BufferedReader(new FileReader(new File("file.dat")));
str = buffread.readLine();
.
.
buffread.close();

this should help you.

How to comment multiple lines with space or indent

Might just be for Visual Studio '15, if you right-click on source code, there's an option for insert comment

This puts summary tags around your comment section, but it does give the indentation that you want.

Postgres "psql not recognized as an internal or external command"

If you tried all the answers and still spinning your heads, don't forget to change the version with your one which you downloaded.

For example, don't simply copy paste

;C:\Program Files\PostgreSQL\9.5\bin ;C:\Program Files\PostgreSQL\9.5\lib

More clearly,

;C:\Program Files\PostgreSQL\[Your Version]\bin ;C:\Program Files\PostgreSQL\[Your Version]\lib

I was spinning my heads. Hope this helps.

What does axis in pandas mean?

The easiest way for me to understand is to talk about whether you are calculating a statistic for each column (axis = 0) or each row (axis = 1). If you calculate a statistic, say a mean, with axis = 0 you will get that statistic for each column. So if each observation is a row and each variable is in a column, you would get the mean of each variable. If you set axis = 1 then you will calculate your statistic for each row. In our example, you would get the mean for each observation across all of your variables (perhaps you want the average of related measures).

axis = 0: by column = column-wise = along the rows

axis = 1: by row = row-wise = along the columns

Check if all elements in a list are identical

A set comparison work:

len(set(the_list)) == 1

Using set removes all duplicate elements.

Pass react component as props

Using this.props.children is the idiomatic way to pass instantiated components to a react component

const Label = props => <span>{props.children}</span>
const Tab = props => <div>{props.children}</div>
const Page = () => <Tab><Label>Foo</Label></Tab>

When you pass a component as a parameter directly, you pass it uninstantiated and instantiate it by retrieving it from the props. This is an idiomatic way of passing down component classes which will then be instantiated by the components down the tree (e.g. if a component uses custom styles on a tag, but it wants to let the consumer choose whether that tag is a div or span):

const Label = props => <span>{props.children}</span>
const Button = props => {
    const Inner = props.inner; // Note: variable name _must_ start with a capital letter 
    return <button><Inner>Foo</Inner></button>
}
const Page = () => <Button inner={Label}/>

If what you want to do is to pass a children-like parameter as a prop, you can do that:

const Label = props => <span>{props.content}</span>
const Tab = props => <div>{props.content}</div>
const Page = () => <Tab content={<Label content='Foo' />} />

After all, properties in React are just regular JavaScript object properties and can hold any value - be it a string, function or a complex object.

Getting a list of associative array keys

for (var key in dictionary) {
  // Do something with key
}

It's the for..in statement.

How to convert Double to int directly?

try casting the value

double d = 1.2345;
long l = (long) d;

MaxLength Attribute not generating client-side validation attributes

I tried this for all the inputs in my html document(textarea,inputs,etc) that had the data-val-length-max property and it works correctly.

$(document).ready(function () {
    $(":input[data-val-length-max]").each(function (index, element) {
        var length = parseInt($(this).attr("data-val-length-max"));
        $(this).prop("maxlength", length);
    });
});

android - listview get item view by position

Preferred way to change the appearance/whatever of row views once the ListView is drawn is to change something in the data ListView draws from (the array of objects that is passed into your Adapter) and make sure to account for that in your getView() function, then redraw the ListView by calling

notifyDataSetChanged();

EDIT: while there is a way to do this, if you need to do this chances are doing something wrong. While are few edge cases I can think about, generally using notifyDataSetChanged() and other built in mechanisms is a way to go.

EDIT 2: One of the common mistakes people make is trying to come up with their own way to respond to user clicking/selecting a row in the ListView, as in one of the comments to this post. There is an existing way to do this. Here's how:

mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    /* Parameters
    parent:     The AdapterView where the click happened.
    view:       The view within the AdapterView that was clicked (this will be a view provided by the adapter)
    position:   The position of the view in the adapter.
    id:         The row id of the item that was clicked. */
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        //your code here
    }
});

ListView has a lot of build-in functionality and there is no need to reinvent the wheel for simpler cases. Since ListView extends AdapterView, you can set the same Listeners, such as OnItemClickListener as in the example above.

How to give a delay in loop execution using Qt

So this question is nearly 10 years old, but it popped up on one of my searches, and I think that there are better solutions when programming in Qt: Signals & slots, timers, and finite state machines. The delays that are required can be implemented without sleeping the application in a way that interrupts other functions, and without concurrent programming and without spinning the processor - the Qt application will sleep when there are no events to process.

A hack for this is to have a sequence of timers with their timeout() signal connected to the slot for the event, which then kicks off the second timer. This is nice because it is simple. It's not so nice because it quickly becomes difficult to troubleshoot and maintain if there are logical branches, which there generally will be outside of any toy example.

QTimer

A better, more flexible option is the State Machine infrastructure within Qt. There you can configure an framework for an arbitrary sequence of events with multiple states and branches. An FSM is much easier to define, expand and maintain over time.

Qt State Machine

Node.js setting up environment specific configs to be used with everyauth

This answer is not something new. It's similar to what @andy_t has mentioned. But I use the below pattern for two reasons.

  1. Clean implementation with No external npm dependencies

  2. Merge the default config settings with the environment based settings.

Javascript implementation

const settings = {
    _default: {
       timeout: 100
       baseUrl: "http://some.api/",
    },
    production: {
       baseUrl: "http://some.prod.api/",
    },
}
// If you are not using ECMAScript 2018 Standard
// https://stackoverflow.com/a/171256/1251350
module.exports = { ...settings._default, ...settings[process.env.NODE_ENV] }

I usually use typescript in my node project. Below is my actual implementation copy-pasted.

Typescript implementation

const settings: { default: ISettings, production: any } = {
    _default: {
        timeout: 100,
        baseUrl: "",
    },
    production: {
        baseUrl: "",
    },
}

export interface ISettings {
    baseUrl: string
}

export const config = ({ ...settings._default, ...settings[process.env.NODE_ENV] } as ISettings)

ASP.NET MVC - passing parameters to the controller

Your routing needs to be set up along the lines of {controller}/{action}/{firstItem}. If you left the routing as the default {controller}/{action}/{id} in your global.asax.cs file, then you will need to pass in id.

routes.MapRoute(
    "Inventory",
    "Inventory/{action}/{firstItem}",
    new { controller = "Inventory", action = "ListAll", firstItem = "" }
);

... or something close to that.

Why are Python's 'private' methods not actually private?

The phrase commonly used is "we're all consenting adults here". By prepending a single underscore (don't expose) or double underscore (hide), you're telling the user of your class that you intend the member to be 'private' in some way. However, you're trusting everyone else to behave responsibly and respect that, unless they have a compelling reason not to (e.g. debuggers, code completion).

If you truly must have something that is private, then you can implement it in an extension (e.g. in C for CPython). In most cases, however, you simply learn the Pythonic way of doing things.

CSS how to make scrollable list

As per your question vertical listing have a scrollbar effect.

CSS / HTML :

_x000D_
_x000D_
nav ul{height:200px; width:18%;}_x000D_
nav ul{overflow:hidden; overflow-y:scroll;}
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
    <head>_x000D_
        <meta charset="utf-8">_x000D_
        <title>JS Bin</title>_x000D_
    </head>_x000D_
    <body>_x000D_
        <header>header area</header>_x000D_
        <nav>_x000D_
            <ul>_x000D_
                <li>Link 1</li>_x000D_
                <li>Link 2</li>_x000D_
                <li>Link 3</li>_x000D_
                <li>Link 4</li>_x000D_
                <li>Link 5</li>_x000D_
                <li>Link 6</li> _x000D_
                <li>Link 7</li> _x000D_
                <li>Link 8</li>_x000D_
                <li>Link 9</li>_x000D_
                <li>Link 10</li>_x000D_
                <li>Link 11</li>_x000D_
                <li>Link 13</li>_x000D_
                <li>Link 13</li>_x000D_
_x000D_
            </ul>_x000D_
        </nav>_x000D_
        _x000D_
        <footer>footer area</footer>_x000D_
    </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

How to open a different activity on recyclerView item onclick

Simply you can do it easy... You just need to get the context of your activity, here, from your View.

//Create intent getting the context of your View and the class where you want to go
Intent intent = new Intent(view.getContext(), YourClass.class);

//start the activity from the view/context
view.getContext().startActivity(intent); //If you are inside activity, otherwise pass context to this funtion

Remember that you need to modify AndroidManifest.xml and place the activity...

<activity
        android:name=".YourClass"
        android:label="Label for your activity"></activity>

GCM with PHP (Google Cloud Messaging)

Here's a library I forked from CodeMonkeysRU.

The reason I forked was because Google requires exponential backoff. I use a redis server to queue messages and resend after a set time.

I've also updated it to support iOS.

https://github.com/stevetauber/php-gcm-queue

How to set cornerRadius for only top-left and top-right corner of a UIView?

I am not sure why your solution did not work but the following code is working for me. Create a bezier mask and apply it to your view. In my code below I was rounding the bottom corners of the _backgroundView with a radius of 3 pixels. self is a custom UITableViewCell:

UIBezierPath *maskPath = [UIBezierPath
    bezierPathWithRoundedRect:self.backgroundImageView.bounds
    byRoundingCorners:(UIRectCornerBottomLeft | UIRectCornerBottomRight)
    cornerRadii:CGSizeMake(20, 20)
];

CAShapeLayer *maskLayer = [CAShapeLayer layer];

maskLayer.frame = self.bounds;
maskLayer.path = maskPath.CGPath;

self.backgroundImageView.layer.mask = maskLayer;

Swift version with some improvements:

let path = UIBezierPath(roundedRect:viewToRound.bounds, byRoundingCorners:[.TopRight, .BottomLeft], cornerRadii: CGSizeMake(20, 20))
let maskLayer = CAShapeLayer()

maskLayer.path = path.CGPath
viewToRound.layer.mask = maskLayer

Swift 3.0 version:

let path = UIBezierPath(roundedRect:viewToRound.bounds,
                        byRoundingCorners:[.topRight, .bottomLeft],
                        cornerRadii: CGSize(width: 20, height:  20))

let maskLayer = CAShapeLayer()

maskLayer.path = path.cgPath
viewToRound.layer.mask = maskLayer

Swift extension here

How to check if a string starts with one of several prefixes?

Do you mean this:

if (newStr4.startsWith("Mon") || newStr4.startsWith("Tues") || ...)

Or you could use regular expression:

if (newStr4.matches("(Mon|Tues|Wed|Thurs|Fri).*"))

Controlling Maven final name of jar artifact

You set the finalName property in the plugin configuration section:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-jar-plugin</artifactId>
    <version>2.3.2</version>
    <configuration>
        <finalName>myJar</finalName>                   
    </configuration>
</plugin>       

As indicated in the official documentation.

Update:

For Maven >= 3

Based on Matthew's comment you can now do it like this:

 <packaging>jar</packaging>
 <build>
   <finalName>WhatEverYouLikey</finalName>
 </build>

See bug report/documentation.

Get query string parameters url values with jQuery / Javascript (querystring)

Found this gem from our friends over at SitePoint. https://www.sitepoint.com/url-parameters-jquery/.

Using PURE jQuery. I just used this and it worked. Tweaked it a bit for example sake.

//URL is http://www.example.com/mypage?ref=registration&[email protected]

$.urlParam = function (name) {
    var results = new RegExp('[\?&]' + name + '=([^&#]*)')
                      .exec(window.location.search);

    return (results !== null) ? results[1] || 0 : false;
}

console.log($.urlParam('ref')); //registration
console.log($.urlParam('email')); //[email protected]

Use as you will.

Is header('Content-Type:text/plain'); necessary at all?

It is very important that you tell the browser what type of data you are sending it. The difference should be obvious. Try viewing the output of the following PHP file in your browser;

<?php
header('Content-Type:text/html');
?>
<p>Hello</p>

You will see:

hello

(note that you will get the same results if you miss off the header line in this case - text/html is php's default)

Change it to text/plain

<?php
header('Content-Type:text/plain');
?>
<p>Hello</p>

You will see:

<p>Hello</p>

Why does this matter? If you have something like the following in a php script that, for example, is used by an ajax request:

<?php
header('Content-Type:text/html');
print "Your name is " . $_GET['name']

Someone can put a link to a URL like http://example.com/test.php?name=%3Cscript%20src=%22http://example.com/eviljs%22%3E%3C/script%3E on their site, and if a user clicks it, they have exposed all their information on your site to whoever put up the link. If you serve the file as text/plain, you are safe.

Note that this is a silly example, it's more likely that the bad script tag would be added by the attacker to a field in the database or by using a form submission.

momentJS date string add 5 days

moment(moment('2015/04/09 16:00:00').add(7, 'd').format('YYYY/MM/DD HH:mm:mm'))

has to format and then convert to moment again.

Flatten an irregular list of lists

Pandas has a function that does this. It returns an iterator as you mentioned.

In [1]: import pandas
In [2]: pandas.core.common.flatten([[[1, 2, 3], [4, 5]], 6])
Out[2]: <generator object flatten at 0x7f12ade66200>
In [3]: list(pandas.core.common.flatten([[[1, 2, 3], [4, 5]], 6]))
Out[3]: [1, 2, 3, 4, 5, 6]

How to show current user name in a cell?

Example: to view the Windows User Name on Cell C5, you can use this script :

Range("C5").Value = ": " & Environ("USERNAME").

'Source code does not match the bytecode' when debugging on a device

I tried the solutions given here while working on an application that used Bluetooth Low Energy(BLE). I tried,

  1. Clean Build
  2. Disabled Instant Run
  3. Invalidate Caches / Restart

all of these failed.

What I did was debug the points where I thought I was getting the warning, I still got the warning but the application was working fine. You can disregard the warning.

Prevent flex items from overflowing a container

If you want the overflow to wrap: flex-flow: row wrap

how do I check in bash whether a file was created more than x time ago?

Although ctime isn't technically the time of creation, it quite often is.

Since ctime it isn't affected by changes to the contents of the file, it's usually only updated when the file is created. And yes - I can hear you all screaming - it's also updated if you change the access permissions or ownership... but generally that's something that's done once, usually at the same time you put the file there.

Personally I always use mtime for everything, and I imagine that is what you want. But anyway... here's a rehash of Guss's "unattractive" bash, in an easy to use function.

#!/bin/bash
function age() {
   local filename=$1
   local changed=`stat -c %Y "$filename"`
   local now=`date +%s`
   local elapsed

   let elapsed=now-changed
   echo $elapsed
}

file="/"
echo The age of $file is $(age "$file") seconds.

vertical-align image in div

If you have a fixed height in your container, you can set line-height to be the same as height, and it will center vertically. Then just add text-align to center horizontally.

Here's an example: http://jsfiddle.net/Cthulhu/QHEnL/1/

EDIT

Your code should look like this:

.img_thumb {
    float: left;
    height: 120px;
    margin-bottom: 5px;
    margin-left: 9px;
    position: relative;
    width: 147px;
    background-color: rgba(0, 0, 0, 0.5);
    border-radius: 3px;
    line-height:120px;
    text-align:center;
}

.img_thumb img {
    vertical-align: middle;
}

The images will always be centered horizontally and vertically, no matter what their size is. Here's 2 more examples with images with different dimensions:

http://jsfiddle.net/Cthulhu/QHEnL/6/

http://jsfiddle.net/Cthulhu/QHEnL/7/

UPDATE

It's now 2016 (the future!) and looks like a few things are changing (finally!!).

Back in 2014, Microsoft announced that it will stop supporting IE8 in all versions of Windows and will encourage all users to update to IE11 or Edge. Well, this is supposed to happen next Tuesday (12th January).

Why does this matter? With the announced death of IE8, we can finally start using CSS3 magic.

With that being said, here's an updated way of aligning elements, both horizontally and vertically:

.container {
    position: relative;
}

.container .element {
   position: absolute;
   left: 50%;
   top: 50%;
   transform: translate(-50%, -50%);
}

Using this transform: translate(); method, you don't even need to have a fixed height in your container, it's fully dynamic. Your element has fixed height or width? Your container as well? No? It doesn't matter, it will always be centered because all centering properties are fixed on the child, it's independent from the parent. Thank you CSS3.

If you only need to center in one dimension, you can use translateY or translateX. Just try it for a while and you'll see how it works. Also, try to change the values of the translate, you will find it useful for a bunch of different situations.

Here, have a new fiddle: https://jsfiddle.net/Cthulhu/1xjbhsr4/

For more information on transform, here's a good resource.

Happy coding.

How do I revert an SVN commit?

svn merge -r 1944:1943 . should revert the changes of r1944 in your working copy. You can then review the changes in your working copy (with diff), but you'd need to commit in order to apply the revert into the repository.

Using Jquery Ajax to retrieve data from Mysql

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

 <html>
 <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){                    
            $("#responsecontainer").html(response); 
            //alert(response);
        }

    });
});
});

</script>

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

</div>
</body>
</html>

For mysqli connection, write this:

<?php 
$con=mysqli_connect("localhost","root",""); 

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

<?php
include("connection.php");
mysqli_select_db("samples",$con);
$result=mysqli_query("select * from student",$con);

echo "<table border='1' >
<tr>
<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>";
?>

Twitter bootstrap collapse: change display of toggle button

Add some jquery code, you need jquery to do this :

<script>
        $(".btn[data-toggle='collapse']").click(function() {
            if ($(this).text() == '+') {
                $(this).text('-');
            } else {
                $(this).text('+');
            }
        });
        </script>

Android Studio: “Execution failed for task ':app:mergeDebugResources'” if project is created on drive C:

I have a similar problem with Error:Execution failed for task ':app:mergeDebugResources. And at last I found the reason is the pictures resource error which use the incorrect ".9.png".

HTML / CSS How to add image icon to input type="button"?

If you're using spritesheets this becomes impossible and the element must be wrapped.

.btn{
    display: inline-block;
    background: blue;
    position: relative;
    border-radius: 5px;
}
.input, .btn:after{
    color: #fff;
}
.btn:after{
    position: absolute;
    content: '@';
    right: 0;
    width: 1.3em;
    height: 1em;
}
.input{
    background: transparent;
    color: #fff;
    border: 0;
    padding-right: 20px;
    cursor: pointer;
    position: relative;
    padding: 5px 20px 5px 5px;
    z-index: 1;
}

Check out this fiddle: http://jsfiddle.net/AJNnZ/

Django request get parameters

You may also use:

request.POST.get('section','') # => [39]
request.POST.get('MAINS','') # => [137] 
request.GET.get('section','') # => [39]
request.GET.get('MAINS','') # => [137]

Using this ensures that you don't get an error. If the POST/GET data with any key is not defined then instead of raising an exception the fallback value (second argument of .get() will be used).

twitter bootstrap 3.0 typeahead ajax example

I'm using this https://github.com/biggora/bootstrap-ajax-typeahead

The result of code using Codeigniter/PHP

<pre>

$("#produto").typeahead({
        onSelect: function(item) {
            console.log(item);
            getProductInfs(item);
        },
        ajax: {
            url: path + 'produto/getProdName/',
            timeout: 500,
            displayField: "concat",
            valueField: "idproduto",
            triggerLength: 1,
            method: "post",
            dataType: "JSON",
            preDispatch: function (query) {
                showLoadingMask(true);
                return {
                    search: query
                }
            },
            preProcess: function (data) {

                if (data.success === false) {
                    return false;
                }else{
                    return data;    
                }                
            }               
        }
    });
</pre>   

Django set default form values

I had this other solution (I'm posting it in case someone else as me is using the following method from the model):

class onlyUserIsActiveField(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super(onlyUserIsActiveField, self).__init__(*args, **kwargs)
        self.fields['is_active'].initial = False

    class Meta:
        model = User
        fields = ['is_active']
        labels = {'is_active': 'Is Active'}
        widgets = {
            'is_active': forms.CheckboxInput( attrs={
                            'class':          'form-control bootstrap-switch',
                            'data-size':      'mini',
                            'data-on-color':  'success',
                            'data-on-text':   'Active',
                            'data-off-color': 'danger',
                            'data-off-text':  'Inactive',
                            'name':           'is_active',

            })
        }

The initial is definded on the __init__ function as self.fields['is_active'].initial = False

Naming convention - underscore in C++ and C# variables

As far as the C and C++ languages are concerned there is no special meaning to an underscore in the name (beginning, middle or end). It's just a valid variable name character. The "conventions" come from coding practices within a coding community.

As already indicated by various examples above, _ in the beginning may mean private or protected members of a class in C++.

Let me just give some history that may be fun trivia. In UNIX if you have a core C library function and a kernel back-end where you want to expose the kernel function to user space as well the _ is stuck in front of the function stub that calls the kernel function directly without doing anything else. The most famous and familiar example of this is exit() vs _exit() under BSD and SysV type kernels: There, exit() does user-space stuff before calling the kernel's exit service, whereas _exit just maps to the kernel's exit service.

So _ was used for "local" stuff in this case local being machine-local. Typically _functions() were not portable. In that you should not expect same behaviour across various platforms.

Now as for _ in variable names, such as

int _foo;

Well psychologically, an _ is an odd thing to have to type in the beginning. So if you want to create a variable name that would have a lesser chance of a clash with something else, ESPECIALLY when dealing with pre-processor substitutions you want consider uses of _.

My basic advice would be to always follow the convention of your coding community, so that you can collaborate more effectively.

How do I solve the INSTALL_FAILED_DEXOPT error?

There's no generic solution, you have to find the error reported on your Logcat to be able to figure it out. Sometimes it's a class that can't be 'dexed' due to an usage of a class not available on the specified Target API for instance. Or it could be a class that you're making reference in your code, but the library that it is in is not being packaged.

Where do alpha testers download Google Play Android apps?

In my experience the flow is:

  • you publish the app as beta in Google Play and create the Google+ community
  • invite the tester to the community
  • once he has joined, send him the link of the test app in Google Play
  • the tester opens the link in the browser (not google play app)
  • registers as tester
  • in the browser, install the apps to the device (the app will be magically pushed to the device)

Getting current unixtimestamp using Moment.js

To find the Unix Timestamp in seconds:

moment().unix()

The documentation is your friend. :)

Node.js get file extension

You can use path.parse(path), for example

const path = require('path');
const { ext } = path.parse('/home/user/dir/file.txt');

Call static methods from regular ES6 class methods

Both ways are viable, but they do different things when it comes to inheritance with an overridden static method. Choose the one whose behavior you expect:

class Super {
  static whoami() {
    return "Super";
  }
  lognameA() {
    console.log(Super.whoami());
  }
  lognameB() {
    console.log(this.constructor.whoami());
  }
}
class Sub extends Super {
  static whoami() {
    return "Sub";
  }
}
new Sub().lognameA(); // Super
new Sub().lognameB(); // Sub

Referring to the static property via the class will be actually static and constantly give the same value. Using this.constructor instead will use dynamic dispatch and refer to the class of the current instance, where the static property might have the inherited value but could also be overridden.

This matches the behavior of Python, where you can choose to refer to static properties either via the class name or the instance self.

If you expect static properties not to be overridden (and always refer to the one of the current class), like in Java, use the explicit reference.

change type of input field with jQuery

This Worked for me.

$('#newpassword_field').attr("type", 'text');

How to check compiler log in sql developer?

control-shift-L should open the log(s) for you. this will by default be the messages log, but if you create the item that is creating the error the Compiler Log will show up (for me the box shows up in the bottom middle left).

if the messages log is the only log that shows up, simply re-execute the item that was causing the failure and the compiler log will show up

for instance, hit Control-shift-L then execute this

CREATE OR REPLACE FUNCTION TEST123() IS
BEGIN
VAR := 2;
end TEST123;

and you will see the message "Error(1,18): PLS-00103: Encountered the symbol ")" when expecting one of the following: current delete exists prior "

(You can also see this in "View--Log")

One more thing, if you are having a problem with a (function || package || procedure) if you do the coding via the SQL Developer interface (by finding the object in question on the connections tab and editing it the error will be immediately displayed (and even underlined at times)

std::unique_lock<std::mutex> or std::lock_guard<std::mutex>?

They are not really same mutexes, lock_guard<muType> has nearly the same as std::mutex, with a difference that it's lifetime ends at the end of the scope (D-tor called) so a clear definition about these two mutexes :

lock_guard<muType> has a mechanism for owning a mutex for the duration of a scoped block.

And

unique_lock<muType> is a wrapper allowing deferred locking, time-constrained attempts at locking, recursive locking, transfer of lock ownership, and use with condition variables.

Here is an example implemetation :

#include <iostream>
#include <thread>
#include <mutex>
#include <condition_variable>
#include <functional>
#include <chrono>

using namespace std::chrono;

class Product{

   public:

       Product(int data):mdata(data){
       }

       virtual~Product(){
       }

       bool isReady(){
       return flag;
       }

       void showData(){

        std::cout<<mdata<<std::endl;
       }

       void read(){

         std::this_thread::sleep_for(milliseconds(2000));

         std::lock_guard<std::mutex> guard(mmutex);

         flag = true;

         std::cout<<"Data is ready"<<std::endl;

         cvar.notify_one();

       }

       void task(){

       std::unique_lock<std::mutex> lock(mmutex);

       cvar.wait(lock, [&, this]() mutable throw() -> bool{ return this->isReady(); });

       mdata+=1;

       }

   protected:

    std::condition_variable cvar;
    std::mutex mmutex;
    int mdata;
    bool flag = false;

};

int main(){

     int a = 0;
     Product product(a);

     std::thread reading(product.read, &product);
     std::thread setting(product.task, &product);

     reading.join();
     setting.join();


     product.showData();
    return 0;
}

In this example, i used the unique_lock<muType> with condition variable

Best way to return a value from a python script

If you want your script to return values, just do return [1,2,3] from a function wrapping your code but then you'd have to import your script from another script to even have any use for that information:

Return values (from a wrapping-function)

(again, this would have to be run by a separate Python script and be imported in order to even do any good):

import ...
def main():
    # calculate stuff
    return [1,2,3]

Exit codes as indicators

(This is generally just good for when you want to indicate to a governor what went wrong or simply the number of bugs/rows counted or w/e. Normally 0 is a good exit and >=1 is a bad exit but you could inter-prate them in any way you want to get data out of it)

import sys
# calculate and stuff
sys.exit(100)

And exit with a specific exit code depending on what you want that to tell your governor. I used exit codes when running script by a scheduling and monitoring environment to indicate what has happened.

(os._exit(100) also works, and is a bit more forceful)

Stdout as your relay

If not you'd have to use stdout to communicate with the outside world (like you've described). But that's generally a bad idea unless it's a parser executing your script and can catch whatever it is you're reporting to.

import sys
# calculate stuff
sys.stdout.write('Bugs: 5|Other: 10\n')
sys.stdout.flush()
sys.exit(0)

Are you running your script in a controlled scheduling environment then exit codes are the best way to go.

Files as conveyors

There's also the option to simply write information to a file, and store the result there.

# calculate
with open('finish.txt', 'wb') as fh:
    fh.write(str(5)+'\n')

And pick up the value/result from there. You could even do it in a CSV format for others to read simplistically.

Sockets as conveyors

If none of the above work, you can also use network sockets locally *(unix sockets is a great way on nix systems). These are a bit more intricate and deserve their own post/answer. But editing to add it here as it's a good option to communicate between processes. Especially if they should run multiple tasks and return values.

find -exec with multiple commands

There's an easier way:

find ... | while read -r file; do
    echo "look at my $file, my $file is amazing";
done

Alternatively:

while read -r file; do
    echo "look at my $file, my $file is amazing";
done <<< "$(find ...)"

Best way to do a PHP switch with multiple values per case?

Version 1 is certainly easier on the eyes, clearer as to your intentions, and easier to add case-conditions to.

I've never tried the second version. In many languages, this wouldn't even compile because each case labels has to evaluate to a constant-expression.

Function to Calculate a CRC16 Checksum

There are several details you need to 'match up' with for a particular CRC implementation - even using the same polynomial there can be different results because of minor differences in how data bits are handled, using a particular initial value for the CRC (sometimes it's zero, sometimes 0xffff), and/or inverting the bits of the CRC. For example, sometimes one implementation will work from the low order bits of the data bytes up, while sometimes they'll work from the high order bits down (as yours currently does).

Also, you need to 'push out' the last bits of the CRC after you've run all the data bits through.

Keep in mind that CRC algorithms were designed to be implemented in hardware, so some of how bit ordering is handled may not make so much sense from a software point of view.

If you want to match the CRC16 with polynomial 0x8005 as shown on the lammertbies.nl CRC calculator page, you need to make the following changes to your CRC function:

  • a) run the data bits through the CRC loop starting from the least significant bit instead of from the most significant bit
  • b) push the last 16 bits of the CRC out of the CRC register after you've finished with the input data
  • c) reverse the CRC bits (I'm guessing this bit is a carry over from hardware implementations)

So, your function might look like:

#define CRC16 0x8005

uint16_t gen_crc16(const uint8_t *data, uint16_t size)
{
    uint16_t out = 0;
    int bits_read = 0, bit_flag;

    /* Sanity check: */
    if(data == NULL)
        return 0;

    while(size > 0)
    {
        bit_flag = out >> 15;

        /* Get next bit: */
        out <<= 1;
        out |= (*data >> bits_read) & 1; // item a) work from the least significant bits

        /* Increment bit counter: */
        bits_read++;
        if(bits_read > 7)
        {
            bits_read = 0;
            data++;
            size--;
        }

        /* Cycle check: */
        if(bit_flag)
            out ^= CRC16;

    }

    // item b) "push out" the last 16 bits
    int i;
    for (i = 0; i < 16; ++i) {
        bit_flag = out >> 15;
        out <<= 1;
        if(bit_flag)
            out ^= CRC16;
    }

    // item c) reverse the bits
    uint16_t crc = 0;
    i = 0x8000;
    int j = 0x0001;
    for (; i != 0; i >>=1, j <<= 1) {
        if (i & out) crc |= j;
    }

    return crc;
}

That function returns 0xbb3d for me when I pass in "123456789".

How to write a cursor inside a stored procedure in SQL Server 2008

What's wrong with just simply using a single, simple UPDATE statement??

UPDATE dbo.Coupon
SET NoofUses = (SELECT COUNT(*) FROM dbo.CouponUse WHERE Couponid = dbo.Coupon.ID)

That's all that's needed ! No messy and complicated cursor, no looping, no RBAR (row-by-agonizing-row) processing ..... just a nice, simple, clean set-based SQL statement.

django templates: include and extends

More info about why it wasn't working for me in case it helps future people:

The reason why it wasn't working is that {% include %} in django doesn't like special characters like fancy apostrophe. The template data I was trying to include was pasted from word. I had to manually remove all of these special characters and then it included successfully.

Using async/await for multiple tasks

I just want to add to all great answers above, that if you write a library it's a good practice to use ConfigureAwait(false) and get better performance, as said here.

So this snippet seems to be better:

 public static async Task DoWork() 
 {
     int[] ids = new[] { 1, 2, 3, 4, 5 };
     await Task.WhenAll(ids.Select(i => DoSomething(1, i))).ConfigureAwait(false);
 }

A full fiddle link here.

Default value of 'boolean' and 'Boolean' in Java

Boolean is an Object. So if it's an instance variable it will be null. If it's declared within a method you will have to initialize it, or there will be a compiler error.

If you declare as a primitive i.e. boolean. The value will be false by default if it's an instance variable (or class variable). If it's declared within a method you will still have to initialize it to either true or false, or there will be a compiler error.

Converting dictionary to JSON

No need to convert it in a string by using json.dumps()

r = {'is_claimed': 'True', 'rating': 3.5}
file.write(r['is_claimed'])
file.write(str(r['rating']))

You can get the values directly from the dict object.

Android webview slow

Adding this android:hardwareAccelerated="true" in the manifest was the only thing that significantly improved the performance for me

More info here: http://developer.android.com/guide/topics/manifest/application-element.html#hwaccel

adb command not found in linux environment

In Ubuntu i could run the following command:

  sudo apt install android-tools-adb

SQL Server procedure declare a list

I've always found it easier to invert the test against the list in situations like this. For instance...

SELECT 
    field0, field1, field2 
FROM 
    my_table 
WHERE 
    ',' + @mysearchlist + ',' LIKE '%,' + CAST(field3 AS VARCHAR) + ',%' 

This means that there is no complicated mish-mash required for the values that you are looking for.

As an example, if our list was ('1,2,3'), then we add a comma to the start and end of our list like so: ',' + @mysearchlist + ','.

We also do the same for the field value we're looking for and add wildcards: '%,' + CAST(field3 AS VARCHAR) + ',%' (notice the % and the , characters).

Finally we test the two using the LIKE operator: ',' + @mysearchlist + ',' LIKE '%,' + CAST(field3 AS VARCHAR) + ',%'.

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

If you use .NET as your middle tier, check the route attribute clearly, for example,

I had issue when it was like this,

[Route("something/{somethingLong: long}")] //Space.

Fixed it by this,

[Route("something/{somethingLong:long}")] //No space

iOS 10 - Changes in asking permissions of Camera, microphone and Photo Library causing application to crash

You have to add this permission in Info.plist for iOS 10.

Photo :

Key       :  Privacy - Photo Library Usage Description    
Value   :  $(PRODUCT_NAME) photo use

Microphone :

Key        :  Privacy - Microphone Usage Description    
Value    :  $(PRODUCT_NAME) microphone use

Camera :

Key       :  Privacy - Camera Usage Description   
Value   :  $(PRODUCT_NAME) camera use

How to "pretty" format JSON output in Ruby on Rails

If you are using RABL you can configure it as described here to use JSON.pretty_generate:

class PrettyJson
  def self.dump(object)
    JSON.pretty_generate(object, {:indent => "  "})
  end
end

Rabl.configure do |config|
  ...
  config.json_engine = PrettyJson if Rails.env.development?
  ...
end

A problem with using JSON.pretty_generate is that JSON schema validators will no longer be happy with your datetime strings. You can fix those in your config/initializers/rabl_config.rb with:

ActiveSupport::TimeWithZone.class_eval do
  alias_method :orig_to_s, :to_s
  def to_s(format = :default)
    format == :default ? iso8601 : orig_to_s(format)
  end
end

VBA: Convert Text to Number

Use the below function (changing [E:E] to the appropriate range for your needs) to circumvent this issue (or change to any other format such as "mm/dd/yyyy"):

[E:E].Select
With Selection
    .NumberFormat = "General"
    .Value = .Value
End With

P.S. In my experience, this VBA solution works SIGNIFICANTLY faster on large data sets and is less likely to crash Excel than using the 'warning box' method.

How to return multiple objects from a Java method?

Why not create a WhateverFunctionResult object that contains your results, and the logic required to parse these results, iterate over then etc. It seems to me that either:

  1. These results objects are intimately tied together/related and belong together, or:
  2. they are unrelated, in which case your function isn't well defined in terms of what it's trying to do (i.e. doing two different things)

I see this sort of issue crop up again and again. Don't be afraid to create your own container/result classes that contain the data and the associated functionality to handle this. If you simply pass the stuff around in a HashMap or similar, then your clients have to pull this map apart and grok the contents each time they want to use the results.

var functionName = function() {} vs function functionName() {}

This is called a Function Expression:

var getRectArea = function(width, height) {
    return width * height;
};

console.log("Area of Rectangle: " + getRectArea(3,4));
// This should return the following result in the console: 
// Area of Rectangle: 12

This is called a Function Declaration:

var w = 5;
var h = 6;

function RectArea(width, height) {  //declaring the function
  return area = width * height;
}                                   //note you do not need ; after }

RectArea(w,h);                      //calling or executing the function
console.log("Area of Rectangle: " + area);
// This should return the following result in the console: 
// Area of Rectangle: 30

Hope this helps explain what is the difference between Function Expression and Function Declaration and how to use them. Thanks.

Http Post With Body

You can use HttpClient and HttpPost to build and send the request.

HttpClient client= new DefaultHttpClient();
HttpPost request = new HttpPost("www.example.com");

List<NameValuePair> pairs = new ArrayList<NameValuePair>();
pairs.add(new BasicNameValuePair("paramName", "paramValue"));

request.setEntity(new UrlEncodedFormEntity(pairs ));
HttpResponse resp = client.execute(request);

Real time data graphing on a line chart with html5

This thread is perhaps very very old now. But want to share these results for someone who see this thread. Ran a comparison betn. Flotr2, ChartJS, highcharts asynchronously. Flotr2 seems to be the quickest. Tested this by passing a new data point every 50ms upto 1000 data points totally. Flotr2 was the quickest for me though it appears to be redrawing charts regularly.

http://jsperf.com/async-charts-test/2

In Tkinter is there any way to make a widget not visible?

import tkinter as tk
...
x = tk.Label(text='Hello', visible=True)
def visiblelabel(lb, visible):
    lb.config(visible=visible)
visiblelabel(x, False)  # Hide
visiblelabel(x, True)  # Show

P.S. config can change any attribute:

x.config(text='Hello')  # Text: Hello
x.config(text='Bye', font=('Arial', 20, 'bold'))  # Text: Bye, Font: Arial Bold 20
x.config(bg='red', fg='white')  # Background: red, Foreground: white

It's a bypass of StringVar, IntVar etc.

Login credentials not working with Gmail SMTP

I had same issue. And I fix it with creating an app-password for Email application on Mac. You can find it at my account -> Security -> Signing in to Google -> App passwords. below is the link for it. https://myaccount.google.com/apppasswords?utm_source=google-account&utm_medium=web

When to use .First and when to use .FirstOrDefault with LINQ?

Ok let me give my two cents. First / Firstordefault are for when you use the second constructor. I won't explain what it is, but it's when you would potentially always use one because you don't want to cause an exception.

person = tmp.FirstOrDefault(new Func<Person, bool>((p) =>
{
    return string.IsNullOrEmpty(p.Relationship);
}));

react-router getting this.props.location in child components

If the above solution didn't work for you, you can use import { withRouter } from 'react-router-dom';


Using this you can export your child class as -

class MyApp extends Component{
    // your code
}

export default withRouter(MyApp);

And your class with Router -

// your code
<Router>
      ...
      <Route path="/myapp" component={MyApp} />
      // or if you are sending additional fields
      <Route path="/myapp" component={() =><MyApp process={...} />} />
<Router>

Converting a String to Object

String extends Object, which means an Object. Object o = a; If you really want to get as Object, you may do like below.

String s = "Hi";

Object a =s;

Why does JSHint throw a warning if I am using const?

Create .jshintrc file in the root dir and add there the latest js version: "esversion": 9 and asi version: "asi": true (it will help you to avoid using semicolons)

{
    "esversion": 9,
    "asi": true
}

Custom Card Shape Flutter SDK

You can also customize the card theme globally with ThemeData.cardTheme:

MaterialApp(
  title: 'savvy',
  theme: ThemeData(
    cardTheme: CardTheme(
      shape: RoundedRectangleBorder(
        borderRadius: const BorderRadius.all(
          Radius.circular(8.0),
        ),
      ),
    ),
    // ...

How do Python functions handle the types of the parameters that you pass in?

You never specify the type; Python has the concept of duck typing; basically the code that processes the parameters will make certain assumptions about them - perhaps by calling certain methods that a parameter is expected to implement. If the parameter is of the wrong type, then an exception will be thrown.

In general it is up to your code to ensure that you are passing around objects of the proper type - there is no compiler to enforce this ahead of time.

Register .NET Framework 4.5 in IIS 7.5

You can find the aspnet_regiis in the following directory:

C:\Windows\Microsoft.NET\Framework64\v4.0.30319

Go to the directory and run the command form there. I guess the path is missing in your PATH variable.

What's the difference between xsd:include and xsd:import?

Use xsd:include to bring in an XSD from the same or no namespace.

Use xsd:import to bring in an XSD from a different namespace.

MySQL: Invalid use of group function

First, the error you're getting is due to where you're using the COUNT function -- you can't use an aggregate (or group) function in the WHERE clause.

Second, instead of using a subquery, simply join the table to itself:

SELECT a.pid 
FROM Catalog as a LEFT JOIN Catalog as b USING( pid )
WHERE a.sid != b.sid
GROUP BY a.pid

Which I believe should return only rows where at least two rows exist with the same pid but there is are at least 2 sids. To make sure you get back only one row per pid I've applied a grouping clause.

Chrome: Uncaught SyntaxError: Unexpected end of input

JSHint is good at finding the location of missing brackets or bad syntax.

How do I create an .exe for a Java program?

If Java is installed on the target machine, there is no need to create an .exe file. A .jar file should be sufficient.

A non-blocking read on a subprocess.PIPE in Python

One solution is to make another process to perform your read of the process, or make a thread of the process with a timeout.

Here's the threaded version of a timeout function:

http://code.activestate.com/recipes/473878/

However, do you need to read the stdout as it's coming in? Another solution may be to dump the output to a file and wait for the process to finish using p.wait().

f = open('myprogram_output.txt','w')
p = subprocess.Popen('myprogram.exe', stdout=f)
p.wait()
f.close()


str = open('myprogram_output.txt','r').read()

Static variables in C++

A static variable declared in a header file outside of the class would be file-scoped in every .c file which includes the header. That means separate copy of a variable with same name is accessible in each of the .c files where you include the header file.

A static class variable on the other hand is class-scoped and the same static variable is available to every compilation unit that includes the header containing the class with static variable.

What's wrong with foreign keys?

One time when an FK might cause you a problem is when you have historical data that references the key (in a lookup table) even though you no longer want the key available.
Obviously the solution is to design things better up front, but I am thinking of real world situations here where you don't always have control of the full solution.
For example: perhaps you have a look up table customer_type that lists different types of customers - lets say you need to remove a certain customer type, but (due to business restraints) aren't able to update the client software, and nobody invisaged this situation when developing the software, the fact that it is a foreign key in some other table may prevent you from removing the row even though you know the historical data that references it is irrelevant.
After being burnt with this a few times you probably lean away from db enforcement of relationships.
(I'm not saying this is good - just giving a reason why you may decide to avoid FKs and db contraints in general)

Avoid line break between html elements

If you need this for several words or elements, but can't apply it to a whole TD or similar, the Span tag can be used.

<span style="white-space: nowrap">Text to break together</span>
    or 
<span class=nobr>Text to break together</span>

If you use the class version, remember to set up the CSS as detailed in the accepted answer.

The Android emulator is not starting, showing "invalid command-line parameter"

NickC is correct. It is also worth pointing out that the SDK location is set in Eclipse > Window menu > Preferences > Android. If your folders are different you can check the 8.3 format of any folder with dir foldername /x at the command prompt.

How do I get a consistent byte representation of strings in C# without manually specifying an encoding?

You can use following code to convert a string to a byte array in .NET

string s_unicode = "abcéabc";
byte[] utf8Bytes = System.Text.Encoding.UTF8.GetBytes(s_unicode);

How to split data into 3 sets (train, validation and test)?

Numpy solution. We will shuffle the whole dataset first (df.sample(frac=1, random_state=42)) and then split our data set into the following parts:

  • 60% - train set,
  • 20% - validation set,
  • 20% - test set

In [305]: train, validate, test = \
              np.split(df.sample(frac=1, random_state=42), 
                       [int(.6*len(df)), int(.8*len(df))])

In [306]: train
Out[306]:
          A         B         C         D         E
0  0.046919  0.792216  0.206294  0.440346  0.038960
2  0.301010  0.625697  0.604724  0.936968  0.870064
1  0.642237  0.690403  0.813658  0.525379  0.396053
9  0.488484  0.389640  0.599637  0.122919  0.106505
8  0.842717  0.793315  0.554084  0.100361  0.367465
7  0.185214  0.603661  0.217677  0.281780  0.938540

In [307]: validate
Out[307]:
          A         B         C         D         E
5  0.806176  0.008896  0.362878  0.058903  0.026328
6  0.145777  0.485765  0.589272  0.806329  0.703479

In [308]: test
Out[308]:
          A         B         C         D         E
4  0.521640  0.332210  0.370177  0.859169  0.401087
3  0.333348  0.964011  0.083498  0.670386  0.169619

[int(.6*len(df)), int(.8*len(df))] - is an indices_or_sections array for numpy.split().

Here is a small demo for np.split() usage - let's split 20-elements array into the following parts: 80%, 10%, 10%:

In [45]: a = np.arange(1, 21)

In [46]: a
Out[46]: array([ 1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20])

In [47]: np.split(a, [int(.8 * len(a)), int(.9 * len(a))])
Out[47]:
[array([ 1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16]),
 array([17, 18]),
 array([19, 20])]

Nexus 7 (2013) and Win 7 64 - cannot install USB driver despite checking many forums and online resources

I also got this problem and found quite simple solution. I have Samsung adb driver installed on my system. I tried "Update driver" -> "Let me pick" -> "Already installed drivers" -> Samsung adb driver. That worked well.

Applying a single font to an entire website with CSS

*{font-family:Algerian;}

this html worked for me. Added to canvas settings in wordpress.

Looks cool - thanks !

Looking for a short & simple example of getters/setters in C#

Simple example

    public  class Simple
    {
        public int Propery { get; set; }
    }

How to hide console window in python?

Simply save it with a .pyw extension. This will prevent the console window from opening.

On Windows systems, there is no notion of an “executable mode”. The Python installer automatically associates .py files with python.exe so that a double-click on a Python file will run it as a script. The extension can also be .pyw, in that case, the console window that normally appears is suppressed.

Explanation at the bottom of section 2.2.2

How to return a class object by reference in C++?

Well, it is maybe not a really beautiful solution in the code, but it is really beautiful in the interface of your function. And it is also very efficient. It is ideal if the second is more important for you (for example, you are developing a library).

The trick is this:

  1. A line A a = b.make(); is internally converted to a constructor of A, i.e. as if you had written A a(b.make());.
  2. Now b.make() should result a new class, with a callback function.
  3. This whole thing can be fine handled only by classes, without any template.

Here is my minimal example. Check only the main(), as you can see it is simple. The internals aren't.

From the viewpoint of the speed: the size of a Factory::Mediator class is only 2 pointers, which is more that 1 but not more. And this is the only object in the whole thing which is transferred by value.

#include <stdio.h>

class Factory {
  public:
    class Mediator;

    class Result {
      public:
        Result() {
          printf ("Factory::Result::Result()\n");
        };

        Result(Mediator fm) {
          printf ("Factory::Result::Result(Mediator)\n");
          fm.call(this);
        };
    };

    typedef void (*MakeMethod)(Factory* factory, Result* result);

    class Mediator {
      private:
        Factory* factory;
        MakeMethod makeMethod;

      public:
        Mediator(Factory* factory, MakeMethod makeMethod) {
          printf ("Factory::Mediator::Mediator(Factory*, MakeMethod)\n");
          this->factory = factory;
          this->makeMethod = makeMethod;
        };

        void call(Result* result) {
          printf ("Factory::Mediator::call(Result*)\n");
          (*makeMethod)(factory, result);
        };
    };
};

class A;

class B : private Factory {
  private:
    int v;

  public:
    B(int v) {
      printf ("B::B()\n");
      this->v = v;
    };

    int getV() const {
      printf ("B::getV()\n");
      return v;
    };

    static void makeCb(Factory* f, Factory::Result* a);

    Factory::Mediator make() {
      printf ("Factory::Mediator B::make()\n");
      return Factory::Mediator(static_cast<Factory*>(this), &B::makeCb);
    };
};

class A : private Factory::Result {
  friend class B;

  private:
    int v;

  public:
    A() {
      printf ("A::A()\n");
      v = 0;
    };

    A(Factory::Mediator fm) : Factory::Result(fm) {
      printf ("A::A(Factory::Mediator)\n");
    };

    int getV() const {
      printf ("A::getV()\n");
      return v;
    };

    void setV(int v) {
      printf ("A::setV(%i)\n", v);
      this->v = v;
    };
};

void B::makeCb(Factory* f, Factory::Result* r) {
      printf ("B::makeCb(Factory*, Factory::Result*)\n");
      B* b = static_cast<B*>(f);
      A* a = static_cast<A*>(r);
      a->setV(b->getV()+1);
    };

int main(int argc, char **argv) {
  B b(42);
  A a = b.make();
  printf ("a.v = %i\n", a.getV());
  return 0;
}

Android - Center TextView Horizontally in LinearLayout

Just use: android:layout_centerHorizontal="true"

It will put the whole textview in the center

Conditional formatting, entire row based

You want to apply a custom formatting rule. The "Applies to" field should be your entire row (If you want to format row 5, put in =$5:$5. The custom formula should be =IF($B$5="X", TRUE, FALSE), shown in the example below.

"Cannot GET /" with Connect on Node.js

You'll see the message Cannot GET / if you don't specify which page it is that you're trying to get, in other words if your URL is something like http://localhost:8180. Make sure you enter a page name, e.g. http://localhost:8180/index.html.

complex if statement in python

It is possible to write like this:

elif var1 in [80, 443] or 1024 < var1 < 65535

This way you check if var1 appears in that a list, then you make just 1 check, didn't repeat the "var1" one extra time, and looks clear:

if var1 in [80, 443] or 1024 < var1 < 65535: print 'good' else: print 'bad' ....:
good

Creating custom function in React component

You can create functions in react components. It is actually regular ES6 class which inherits from React.Component. Just be careful and bind it to the correct context in onClick event:

export default class Archive extends React.Component { 

    saySomething(something) {
        console.log(something);
    }

    handleClick(e) {
        this.saySomething("element clicked");
    }

    componentDidMount() {
        this.saySomething("component did mount");
    }

    render() {
        return <button onClick={this.handleClick.bind(this)} value="Click me" />;
    }
}

How to create the branch from specific commit in different branch

You have to do:

git branch <branch_name> <commit>

(you were interchanging the branch name and commit)

Or you can do:

git checkout -b <branch_name> <commit>

If in place of you use branch name, you get a branch out of tip of the branch.

When doing a MERGE in Oracle SQL, how can I update rows that aren't matched in the SOURCE?

You can do it with a separate UPDATE statement

UPDATE report.TEST target
SET    is Deleted = 'Y'
WHERE  NOT EXISTS (SELECT 1
                   FROM   main.TEST source
                   WHERE  source.ID = target.ID);

I don't know of any way to integrate this into your MERGE statement.

Python: Select subset from list based on index set

Assuming you only have the list of items and a list of true/required indices, this should be the fastest:

property_asel = [ property_a[index] for index in good_indices ]

This means the property selection will only do as many rounds as there are true/required indices. If you have a lot of property lists that follow the rules of a single tags (true/false) list you can create an indices list using the same list comprehension principles:

good_indices = [ index for index, item in enumerate(good_objects) if item ]

This iterates through each item in good_objects (while remembering its index with enumerate) and returns only the indices where the item is true.


For anyone not getting the list comprehension, here is an English prose version with the code highlighted in bold:

list the index for every group of index, item that exists in an enumeration of good objects, if (where) the item is True

How can I copy columns from one sheet to another with VBA in Excel?

Private Sub Worksheet_Change(ByVal Target As Range)
  Dim rng As Range, r As Range
  Set rng = Intersect(Target, Range("a2:a" & Rows.Count))
  If rng Is Nothing Then Exit Sub
    For Each r In rng
      If Not IsEmpty(r.Value) Then
        r.Copy Destination:=Sheets("sheet2").Range("a2")
      End If
    Next
  Set rng = Nothing
End Sub

MySQL Insert into multiple tables? (Database normalization?)

Just a remark about your saying

Hi, I tried searching a way to insert information in multiple tables in the same query

Do you eat all your lunch dishes mixed with drinks in the same bowl?
I suppose - no.

Same here.
There are things we do separately.
2 insert queries are 2 insert queries. It's all right. Nothing wrong with it. No need to mash it in one.
Same for select. Query must be sensible and do it's job. That's the only reasons. Number of queries is not.

As for the transactions - you may use them, but it's not THAT big deal for the average web-site. If it happened once a year (if ever) that one user registration being broken you'll be able to fix, no doubt.
there are hundreds of thousands sites running mysql with no transaction support driver. Have you heard of terrible disasters breaking these sites apart? Me neither.

And mysql_insert_id() has noting to do with transactions. you may include in into transaction all right. it's just different matters. Someone raised this question out of nowhere.

How do I assign ls to an array in Linux Bash?

This would print the files in those directories line by line.

array=(ww/* ee/* qq/*)
printf "%s\n" "${array[@]}"

Nullable property to entity field, Entity Framework through Code First

Just omit the [Required] attribute from the string somefield property. This will make it create a NULLable column in the db.

To make int types allow NULLs in the database, they must be declared as nullable ints in the model:

// an int can never be null, so it will be created as NOT NULL in db
public int someintfield { get; set; }

// to have a nullable int, you need to declare it as an int?
// or as a System.Nullable<int>
public int? somenullableintfield { get; set; }
public System.Nullable<int> someothernullableintfield { get; set; }

How to open Emacs inside Bash

emacs hello.c -nw

This is to open a hello.c file using Emacs inside the terminal.

OAuth: how to test with local URLs?

For Mac users, edit the /etc/hosts file. You have to use sudo vi /etc/hosts if its read-only. After authorization, the oauth server sends the callback URL, and since that callback URL is rendered on your local browser, the local DNS setting will work:

127.0.0.1       mylocal.com

Current date without time

Try this:

   var mydtn = DateTime.Today;
   var myDt = mydtn.Date;return myDt.ToString("d", CultureInfo.GetCultureInfo("en-US"));

find all subsets that sum to a particular value

Here is an efficient solution when there is a large set of inputs (i.e. 25 to 30)

I made efficiency gains in two ways:

  • Utilized a simple rolling wheel concept for binary counting through all possible iterations, rather than using mathematically expensive base conversion language features. This "wheel" is akin to an old mechanical counter or odometer. It recursively rolls forward as many positions as necessary until we surpass the number of binary digits we have (e.g., the count of numbers in our set).
  • The main gain is from not summing the entire candidate set each time. Instead, it maintains a running sum and each time it "rolls the wheel", it adjusts the running sum only for the pieces that changed from the last candidate set it tested. This saves a lot of computation since most "wheel rolls" only change a number or two.

This solution works with negative numbers, decimal amounts, and repeated input values. Due to the wonky way that floating point decimal math works in most languages, you will want to keep your input set to only a few decimal places or you may have some unpredictable behavior.

On my old 2012-era desktop computer the given code processes 25 input values in about 0.8 seconds in javascript/node.js, and 3.4 seconds in C#.

javascript

let numbers = [-0.47, -0.35, -0.19, 0.23, 0.36, 0.47, 0.51, 0.59, 0.63, 0.79, 0.85, 
0.91, 0.99, 1.02, 1.17, 1.25, 1.39, 1.44, 1.59, 1.60, 1.79, 1.88, 1.99, 2.14, 2.31];

let target = 24.16;

displaySubsetsThatSumTo(target, numbers);

function displaySubsetsThatSumTo(target, numbers)
{
    let wheel = [0];
    let resultsCount = 0;
    let sum = 0;
    
    const start = new Date();
    do {
        sum = incrementWheel(0, sum, numbers, wheel);
        //Use subtraction comparison due to javascript float imprecision
        if (sum != null && Math.abs(target - sum) < 0.000001) {
            //Found a subset. Display the result.
            console.log(numbers.filter(function(num, index) {
                return wheel[index] === 1;
            }).join(' + ') + ' = ' + target);
            resultsCount++;
        }
    } while (sum != null);
    const end = new Date();
    
    console.log('--------------------------');
    console.log(`Processed ${numbers.length} numbers in ${(end - start) / 1000} seconds (${resultsCount} results)`);
}

function incrementWheel(position, sum, numbers, wheel) {
    if (position === numbers.length || sum === null) {
        return null;
    }
    wheel[position]++;
    if (wheel[position] === 2) {
        wheel[position] = 0;
        sum -= numbers[position];
        if (wheel.length < position + 2) {
            wheel.push(0);
        }
        sum = incrementWheel(position + 1, sum, numbers, wheel);
    }
    else {
        sum += numbers[position];
    }
    return sum;
}

-----------------------------------------------------------------
Alternate, more efficient version using Gray Code binary counting
technique as suggested in comment
-----------------------------------------------------------------

const numbers = [-0.47, -0.35, -0.19, 0.23, 0.36, 0.47, 0.51, 
    0.59, 0.63, 0.79, 0.85, 0.91, 0.99, 1.02, 1.17, 1.25,
     1.39, 1.44, 1.59, 1.60, 1.79, 1.88, 1.99, 2.14, 2.31];
const target = 24.16;

displaySubsetsThatSumTo(target, numbers);

function displaySubsetsThatSumTo(target, numbers)
{
    let resultsCount = 0;
    let sum = 0;
    let wheel = []; //binary counter
    let changeEvery = []; //how often each binary digit flips
    let nextChange = []; //when each binary digit will next flip
    for(let i = 0; i < numbers.length; i++) {
        //Initialize wheel and wheel-update data. Using Gray Code binary counting technique,
        //    whereby only one binary digit in the wheel changes on each iteration. Then only
        //    a single sum operation is required each iteration.
        wheel.push(0);
        changeEvery.push(2 ** (numbers.length - i));
        nextChange.push(2 ** (numbers.length - i - 1));
    }
   
    const start = new Date();

    const numIterations = 2 ** numbers.length;
    for (counter = 1; counter < numIterations; counter++) {
        for (let i = nextChange.length - 1; i >= 0; i--) {
            if(nextChange[i] === counter) {
                nextChange[i] += changeEvery[i];
                if (wheel[i] === 1) {
                    wheel[i] = 0;
                    sum -= numbers[i];
                }
                else {
                    wheel[i] = 1;
                    sum += numbers[i];
                }
                
                break;
            }
        }

        //Use subtraction comparison due to javascript float imprecision
        if (Math.abs(target - sum) < 0.000001) {
            //Found a subset. Display the result.
            console.log(numbers.filter((num, index) => wheel[index] === 1)
                .join(' + ') + ' = ' + target);
            resultsCount++;
        }
    }

    const end = new Date();
    
    console.log('--------------------------');
    console.log(`Processed ${numbers.length} numbers in ${(end - start) / 1000} seconds (${resultsCount} results)`);
}

C#

    public class Program
    {
        static void Main(string[] args)
        {
            double[] numbers = { -0.47, -0.35, -0.19, 0.23, 0.36, 0.47, 0.51, 0.59, 0.63, 0.79, 0.85,
                0.91, 0.99, 1.02, 1.17, 1.25, 1.39, 1.44, 1.59, 1.60, 1.79, 1.88, 1.99, 2.14, 2.31 };

            double target = 24.16;

            DisplaySubsetsThatSumTo(target, numbers);
        }

        private static void DisplaySubsetsThatSumTo(double Target, double[] numbers)
        {
            var stopwatch = new System.Diagnostics.Stopwatch();

            bool[] wheel = new bool[numbers.Length];
            int resultsCount = 0;
            double? sum = 0;

            stopwatch.Start();

            do
            {
                sum = IncrementWheel(0, sum, numbers, wheel);
                //Use subtraction comparison due to double type imprecision
                if (sum.HasValue && Math.Abs(sum.Value - Target) < 0.000001F)
                {
                    //Found a subset. Display the result.
                    Console.WriteLine(string.Join(" + ", numbers.Where((n, idx) => wheel[idx])) + " = " + Target);
                    resultsCount++;
                }
            } while (sum != null);

            stopwatch.Stop();

            Console.WriteLine("--------------------------");
            Console.WriteLine($"Processed {numbers.Length} numbers in {stopwatch.ElapsedMilliseconds / 1000.0} seconds ({resultsCount} results). Press any key to exit.");
            Console.ReadKey();
        }

        private static double? IncrementWheel(int Position, double? Sum, double[] numbers, bool[] wheel)
        {
            if (Position == numbers.Length || !Sum.HasValue)
            {
                return null;
            }
            wheel[Position] = !wheel[Position];
            if (!wheel[Position])
            {
                Sum -= numbers[Position];
                Sum = IncrementWheel(Position + 1, Sum, numbers, wheel);
            }
            else
            {
                Sum += numbers[Position];
            }
            return Sum;
        }
    }

Output

-0.35 + 0.23 + 0.36 + 0.47 + 0.51 + 0.59 + 0.63 + 0.79 + 0.85 + 0.91 + 0.99 + 1.02 + 1.17 + 1.25 + 1.44 + 1.59 + 1.6 + 1.79 + 1.88 + 1.99 + 2.14 + 2.31 = 24.16
0.23 + 0.51 + 0.59 + 0.63 + 0.79 + 0.85 + 0.99 + 1.02 + 1.17 + 1.25 + 1.39 + 1.44 + 1.59 + 1.6 + 1.79 + 1.88 + 1.99 + 2.14 + 2.31 = 24.16
-0.47 + 0.23 + 0.47 + 0.51 + 0.59 + 0.63 + 0.79 + 0.85 + 0.99 + 1.02 + 1.17 + 1.25 + 1.39 + 1.44 + 1.59 + 1.6 + 1.79 + 1.88 + 1.99 + 2.14 + 2.31 = 24.16
-0.19 + 0.36 + 0.51 + 0.59 + 0.63 + 0.79 + 0.91 + 0.99 + 1.02 + 1.17 + 1.25 + 1.39 + 1.44 + 1.59 + 1.6 + 1.79 + 1.88 + 1.99 + 2.14 + 2.31 = 24.16
-0.47 + -0.19 + 0.36 + 0.47 + 0.51 + 0.59 + 0.63 + 0.79 + 0.91 + 0.99 + 1.02 + 1.17 + 1.25 + 1.39 + 1.44 + 1.59 + 1.6 + 1.79 + 1.88 + 1.99 + 2.14 + 2.31 = 24.16
0.23 + 0.47 + 0.51 + 0.63 + 0.85 + 0.91 + 0.99 + 1.02 + 1.17 + 1.25 + 1.39 + 1.44 + 1.59 + 1.6 + 1.79 + 1.88 + 1.99 + 2.14 + 2.31 = 24.16
--------------------------
Processed 25 numbers in 0.823 seconds (6 results)

How to get second-highest salary employees in a table

Try this:

 WITH CTE AS
 (
 SELECT DENSE_RANK() OVER (ORDER BY SALARY DESC)RN,* FROM Users
 )
 SELECT * FROM CTE WHERE RN=2

A default document is not configured for the requested URL, and directory browsing is not enabled on the server

I faced the same error posted by OP while trying to debug my ASP.NET website using IIS Express server. IIS Express is used by Visual Studio to run the website when we press F5.

Open solution explorer in Visual Studio -> Expand the web application project node (StudentInfo in my case) -> Right click on the web page which you want to get loaded when your website starts(StudentPortal.aspx in my case) -> Select Set as Start Page option from the context menu as shown below. It started to work from the next run.

enter image description here

Root cause: I concluded that the start page which is the default document for the website wasn't set correctly or had got messed up somehow during development.

What is {this.props.children} and when you should use it?

props.children represents the content between the opening and the closing tags when invoking/rendering a component:

const Foo = props => (
  <div>
    <p>I'm {Foo.name}</p>
    <p>abc is: {props.abc}</p>

    <p>I have {props.children.length} children.</p>
    <p>They are: {props.children}.</p>
    <p>{Array.isArray(props.children) ? 'My kids are an array.' : ''}</p>
  </div>
);

const Baz = () => <span>{Baz.name} and</span>;
const Bar = () => <span> {Bar.name}</span>;

invoke/call/render Foo:

<Foo abc={123}>
  <Baz />
  <Bar />
</Foo>

props and props.children

PHP Warning: Division by zero

You can try with this. You have this error because we can not divide by 'zero' (0) value. So we want to validate before when we do calculations.

if ($itemCost != 0 && $itemCost != NULL && $itemQty != 0 && $itemQty != NULL) 
{
    $diffPricePercent = (($actual * 100) / $itemCost) / $itemQty;
}

And also we can validate POST data. Refer following

$itemQty = isset($_POST['num1']) ? $_POST['num1'] : 0;

$itemCost = isset($_POST['num2']) ? $_POST['num2'] : 0;

$itemSale = isset($_POST['num3']) ? $_POST['num3'] : 0;

$shipMat = isset($_POST['num4']) ? $_POST['num4'] : 0;

How to export SQL Server database to MySQL?

I used the below connection string on the Advanced tab of MySQL Migration Tool Kit to connect to SQL Server 2008 instance:

jdbc:jtds:sqlserver://"sql_server_ip_address":1433/<db_name>;Instance=<sqlserver_instanceName>;user=sa;password=PASSWORD;namedPipe=true;charset=utf-8;domain= 

Usually the parameter has "systemName\instanceName". But in the above, do not add "systemName\" (use only InstanceName).

To check what the instanceName should be, go to services.msc and check the DisplayName of the MSSQL instance. It shows similar to MSSQL$instanceName.

Hope this help in MSSQL connectivity from mysql migration toolKit.

Display images in asp.net mvc

It is possible to use a handler to do this, even in MVC4. Here's an example from one i made earlier:

public class ImageHandler : IHttpHandler
{
    byte[] bytes;

    public void ProcessRequest(HttpContext context)
    {
        int param;
        if (int.TryParse(context.Request.QueryString["id"], out param))
        {
            using (var db = new MusicLibContext())
            {
                if (param == -1)
                {
                    bytes = File.ReadAllBytes(HttpContext.Current.Server.MapPath("~/Images/add.png"));

                    context.Response.ContentType = "image/png";
                }
                else
                {
                    var data = (from x in db.Images
                                where x.ImageID == (short)param
                                select x).FirstOrDefault();

                    bytes = data.ImageData;

                    context.Response.ContentType = "image/" + data.ImageFileType;
                }

                context.Response.Cache.SetCacheability(HttpCacheability.NoCache);
                context.Response.BinaryWrite(bytes);
                context.Response.Flush();
                context.Response.End();
            }
        }
        else
        {
            //image not found
        }
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }
    }
}

In the view, i added the ID of the photo to the query string of the handler.

How to execute my SQL query in CodeIgniter

http://www.bsourcecode.com/codeigniter/codeigniter-select-query/

$query = $this->db->query("select * from tbl_user");

OR

$query = $this->db->select("*");
            $this->db->from('table_name');
            $query=$this->db->get();

Repeat a string in JavaScript a number of times

In a new ES6 harmony, you will have native way for doing this with repeat. Also ES6 right now only experimental, this feature is already available in Edge, FF, Chrome and Safari

"abc".repeat(3) // "abcabcabc"

And surely if repeat function is not available you can use old-good Array(n + 1).join("abc")

CodeIgniter: How to use WHERE clause and OR clause

You can use this :

$this->db->select('*');
$this->db->from('mytable');
$this->db->where(name,'Joe');
$bind = array('boss', 'active');
$this->db->where_in('status', $bind);

Checking if output of a command contains a certain string in a shell script

Test the return value of grep:

./somecommand | grep 'string' &> /dev/null
if [ $? == 0 ]; then
   echo "matched"
fi

which is done idiomatically like so:

if ./somecommand | grep -q 'string'; then
   echo "matched"
fi

and also:

./somecommand | grep -q 'string' && echo 'matched'

What is the difference between Swing and AWT?

Several consequences result from this difference between AWT and Swing.

AWT is a thin layer of code on top of the OS, whereas Swing is much larger. Swing also has very much richer functionality. Using AWT, you have to implement a lot of things yourself, while Swing has them built in. For GUI-intensive work, AWT feels very primitive to work with compared to Swing. Because Swing implements GUI functionality itself rather than relying on the host OS, it can offer a richer environment on all platforms Java runs on. AWT is more limited in supplying the same functionality on all platforms because not all platforms implement the same-looking controls in the same ways.

Swing components are called "lightweight" because they do not require a native OS object to implement their functionality. JDialog and JFrame are heavyweight, because they do have a peer. So components like JButton, JTextArea, etc., are lightweight because they do not have an OS peer.

A peer is a widget provided by the operating system, such as a button object or an entry field object.

Detecting IE11 using CSS Capability/Feature Detection

You can use js and add a class in html to maintain the standard of conditional comments:

  var ua = navigator.userAgent,
      doc = document.documentElement;

  if ((ua.match(/MSIE 10.0/i))) {
    doc.className = doc.className + " ie10";

  } else if((ua.match(/rv:11.0/i))){
    doc.className = doc.className + " ie11";
  }

Or use a lib like bowser:

https://github.com/ded/bowser

Or modernizr for feature detection:

http://modernizr.com/

I want to declare an empty array in java and then I want do update it but the code is not working

You need to give the array a size:

public static void main(String args[])
{
    int array[] = new int[4];
    int number = 5, i = 0,j = 0;
    while (i<4){
        array[i]=number;
        i=i+1;
    }
    while (j<4){
        System.out.println(array[j]);
        j++;
    }
}

Importing JSON into an Eclipse project

Download the json jar from here. This will solve your problem.

Keyboard shortcuts in WPF

Although the top answers are correct, I personally like to work with attached properties to enable the solution to be applied to any UIElement, especially when the Window is not aware of the element that should be focused. In my experience I often see a composition of several view models and user controls, where the window is often nothing more that the root container.

Snippet

public sealed class AttachedProperties
{
    // Define the key gesture type converter
    [System.ComponentModel.TypeConverter(typeof(System.Windows.Input.KeyGestureConverter))]
    public static KeyGesture GetFocusShortcut(DependencyObject dependencyObject)
    {
        return (KeyGesture)dependencyObject?.GetValue(FocusShortcutProperty);
    }

    public static void SetFocusShortcut(DependencyObject dependencyObject, KeyGesture value)
    {
        dependencyObject?.SetValue(FocusShortcutProperty, value);
    }

    /// <summary>
    /// Enables window-wide focus shortcut for an <see cref="UIElement"/>.
    /// </summary>
    // Using a DependencyProperty as the backing store for FocusShortcut.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty FocusShortcutProperty =
        DependencyProperty.RegisterAttached("FocusShortcut", typeof(KeyGesture), typeof(AttachedProperties), new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.None, new PropertyChangedCallback(OnFocusShortcutChanged)));

    private static void OnFocusShortcutChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        if (!(d is UIElement element) || e.NewValue == e.OldValue)
            return;

        var window = FindParentWindow(d);
        if (window == null)
            return;

        var gesture = GetFocusShortcut(d);
        if (gesture == null)
        {
            // Remove previous added input binding.
            for (int i = 0; i < window.InputBindings.Count; i++)
            {
                if (window.InputBindings[i].Gesture == e.OldValue && window.InputBindings[i].Command is FocusElementCommand)
                    window.InputBindings.RemoveAt(i--);
            }
        }
        else
        {
            // Add new input binding with the dedicated FocusElementCommand.
            // see: https://gist.github.com/shuebner20/349d044ed5236a7f2568cb17f3ed713d
            var command = new FocusElementCommand(element);
            window.InputBindings.Add(new InputBinding(command, gesture));
        }
    }
}

With this attached property you can define a focus shortcut for any UIElement. It will automatically register the input binding at the window containing the element.

Usage (XAML)

<TextBox x:Name="SearchTextBox"
         Text={Binding Path=SearchText}
         local:AttachedProperties.FocusShortcutKey="Ctrl+Q"/>

Source code

The full sample including the FocusElementCommand implementation is available as gist: https://gist.github.com/shuebner20/c6a5191be23da549d5004ee56bcc352d

Disclaimer: You may use this code everywhere and free of charge. Please keep in mind, that this is a sample that is not suitable for heavy usage. For example, there is no garbage collection of removed elements because the Command will hold a strong reference to the element.

Google Play on Android 4.0 emulator

Download Google apps (GoogleLoginService.apk , GoogleServicesFramework.apk , Phonesky.apk)
from here.

Start your emulator:

emulator -avd VM_NAME_HERE -partition-size 500 -no-audio -no-boot-anim

Then use the following commands:

# Remount in rw mode.
# NOTE: more recent system.img files are ext4, not yaffs2
adb shell mount -o remount,rw -t yaffs2 /dev/block/mtdblock0 /system

# Allow writing to app directory on system partition
adb shell chmod 777 /system/app

# Install following apk
adb push GoogleLoginService.apk /system/app/.
adb push GoogleServicesFramework.apk /system/app/.
adb push Phonesky.apk /system/app/. # Vending.apk in older versions
adb shell rm /system/app/SdkSetup*

How to get access to raw resources that I put in res folder?

For raw files, you should consider creating a raw folder inside res directory and then call getResources().openRawResource(resourceName) from your activity.

Visual Studio 2008 Product Key in Registry?

Just delete key:

HKEY_CURRENT_USER/Software/Microsoft/VCExpress/9.0/Registration

Or run in command line:

reg delete HKCU\Software\Microsoft\VCExpress\9.0\Registration /f

Bootstrap 4 align navbar items to the right

Just copied this from one of the getbootstrap pages for the released version 4 which worked much better than the above

<div class="d-none d-xl-block col-xl-2 bd-toc float-md-right">
    <ul class="section-nav">
         <li class="toc-entry toc-h2"><a href="#overview">Overview</a></li>
         <li class="toc-entry toc-h2"><a href="#classes">Classes</a></li>
         <li class="toc-entry toc-h2"><a href="#mixins">Mixins</a></li>
         <li class="toc-entry toc-h2"><a href="#responsive">Responsive</a></li>
    </ul>
</div> 

setting textColor in TextView in layout/main.xml main layout file not referencing colors.xml file. (It wants a #RRGGBB instead of @color/text_color)

After experimenting on that case: android:textColor="@colors/text_color" is wrong since @color is not filename dependant. You can name your resource file foobar.xml, it doesn't matter but if you have defined some colors in it you can access them using @color/some_color.

Update:

file location: res/values/colors.xml The filename is arbitrary. The element's name will be used as the resource ID. (Source)

SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder". error

You haven't specify version in your maven dependency file may be thats why it is not picking the latest jar
As well as you need another deppendency with slf4j-log4j12 artifact id.
Include this in your pom file

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-log4j12</artifactId>
    <version>1.5.6</version>
</dependency>

Let me know if error is still not resolved
I also recomend you to see this link

How to disable spring security for particular url

This may be not the full answer to your question, however if you are looking for way to disable csrf protection you can do:

@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
                .antMatchers("/web/admin/**").hasAnyRole(ADMIN.toString(), GUEST.toString())
                .anyRequest().permitAll()
                .and()
                .formLogin().loginPage("/web/login").permitAll()
                .and()
                .csrf().ignoringAntMatchers("/contact-email")
                .and()
                .logout().logoutUrl("/web/logout").logoutSuccessUrl("/web/").permitAll();
    }

    @Autowired
    public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception {
        auth.inMemoryAuthentication()
                .withUser("admin").password("admin").roles(ADMIN.toString())
                .and()
                .withUser("guest").password("guest").roles(GUEST.toString());
    }

}

I have included full configuration but the key line is:

.csrf().ignoringAntMatchers("/contact-email")

Pandas split column of lists into multiple columns

list comprehension

simple implementation with list comprehension ( my favorite)

df = pd.DataFrame([pd.Series(x) for x in df.teams])
df.columns = ['team_{}'.format(x+1) for x in df.columns]

timing on output:

CPU times: user 0 ns, sys: 0 ns, total: 0 ns
Wall time: 2.71 ms

output:

team_1  team_2
0   SF  NYG
1   SF  NYG
2   SF  NYG
3   SF  NYG
4   SF  NYG
5   SF  NYG
6   SF  NYG

iFrame onload JavaScript event

_x000D_
_x000D_
document.querySelector("iframe").addEventListener( "load", function(e) {_x000D_
_x000D_
    this.style.backgroundColor = "red";_x000D_
    alert(this.nodeName);_x000D_
_x000D_
    console.log(e.target);_x000D_
_x000D_
} );
_x000D_
<iframe src="example.com" ></iframe>
_x000D_
_x000D_
_x000D_

Unmarshaling nested JSON objects

Like what Volker mentioned, nested structs is the way to go. But if you really do not want nested structs, you can override the UnmarshalJSON func.

https://play.golang.org/p/dqn5UdqFfJt

type A struct {
    FooBar string // takes foo.bar
    FooBaz string // takes foo.baz
    More   string 
}

func (a *A) UnmarshalJSON(b []byte) error {

    var f interface{}
    json.Unmarshal(b, &f)

    m := f.(map[string]interface{})

    foomap := m["foo"]
    v := foomap.(map[string]interface{})

    a.FooBar = v["bar"].(string)
    a.FooBaz = v["baz"].(string)
    a.More = m["more"].(string)

    return nil
}

Please ignore the fact that I'm not returning a proper error. I left that out for simplicity.

UPDATE: Correctly retrieving "more" value.

Is Spring annotation @Controller same as @Service?

No, they are pretty different from each other.

Both are different specializations of @Component annotation (in practice, they're two different implementations of the same interface) so both can be discovered by the classpath scanning (if you declare it in your XML configuration)

@Service annotation is used in your service layer and annotates classes that perform service tasks, often you don't use it but in many case you use this annotation to represent a best practice. For example, you could directly call a DAO class to persist an object to your database but this is horrible. It is pretty good to call a service class that calls a DAO. This is a good thing to perform the separation of concerns pattern.

@Controller annotation is an annotation used in Spring MVC framework (the component of Spring Framework used to implement Web Application). The @Controller annotation indicates that a particular class serves the role of a controller. The @Controller annotation acts as a stereotype for the annotated class, indicating its role. The dispatcher scans such annotated classes for mapped methods and detects @RequestMapping annotations.

So looking at the Spring MVC architecture you have a DispatcherServlet class (that you declare in your XML configuration) that represent a front controller that dispatch all the HTTP Request towards the appropriate controller classes (annotated by @Controller). This class perform the business logic (and can call the services) by its method. These classes (or its methods) are typically annotated also with @RequestMapping annotation that specify what HTTP Request is handled by the controller and by its method.

For example:

@Controller
@RequestMapping("/appointments")
public class AppointmentsController {

    private final AppointmentBook appointmentBook;

    @Autowired
    public AppointmentsController(AppointmentBook appointmentBook) {
        this.appointmentBook = appointmentBook;
    }

    @RequestMapping(method = RequestMethod.GET)
    public Map<String, Appointment> get() {
        return appointmentBook.getAppointmentsForToday();
    }

This class is a controller.

This class handles all the HTTP Request toward "/appointments" "folder" and in particular the get method is the method called to handle all the GET HTTP Request toward the folder "/appointments".

I hope that now it is more clear for you.

How to use Apple's new .p8 certificate for APNs in firebase console

Firebase console is now accepting .p8 file, in fact, it's recommending to upload .p8 file.

You can see in below-attached screenshot

Is it valid to have a html form inside another html form?

No, the HTML specification states that no FORM element should contain another FORM element.

How to improve Netbeans performance?

Don't invest time in optimizing your NB installation as long as you can scale vertically: get a SSD (and faster hardware in general).

Also:

  • Add an exception for all relevant folders (e.g. project dir, temp dir) to your anti virus software (or better, get rid of it).
  • Don't use network drives for your projects
    • check if your home drive is local
    • check if your IDE uses non-local folders (e.g. %AppData%)

What is the reason for a red exclamation mark next to my project in Eclipse?

To Remove RED EXCLAMATION mark on project,
I have deleted all JAR files using BUILD Path--> LIBRARY --> ADD EXTERNAL JARs and remove all or selected JAR.
Reinstall again.
This action resolve my issue with Red exclamation mark.

Bootstrap NavBar with left, center or right aligned items

The simplest solution:

Just divide the navbar into columns: for instance, if you have 24 columns over all, 12 are going to be empty and 12 are going to contrain the navbar:

<nav class="navbar navbar-default">
    <div class="row">
       <div class="col-sm-4"></div>
       <div class="col-sm-4"></div>
       <div class="col-sm-4"></div>

       <div class="col-sm-12">
           <ul class="nav navbar-nav" align="center">
              <li><a href="#">Home</a></li>
              <li><a href="#">First Link</a></li>
              <li><a href="#">Second Link</a></li>
              <li><a href="#">Third Link</a></li>
              <li><a href="#">Fourth Link</a></li>
           </ul>
       </div>
    </div>
</nav>

How do I check/uncheck all checkboxes with a button using jQuery?

Try below code to check/uncheck all checkboxes

_x000D_
_x000D_
jQuery(document).ready(function() {_x000D_
    $("#check_uncheck").change(function() {_x000D_
        if ($("#check_uncheck:checked").length) {_x000D_
            $(".checkboxes input:checkbox").prop("checked", true);_x000D_
        } else {_x000D_
            $(".checkboxes input:checkbox").prop("checked", false);_x000D_
        }_x000D_
    })_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>_x000D_
<input type="checkbox" name="check_uncheck" id="check_uncheck" /> Check All/Uncheck All_x000D_
<br/>_x000D_
<br/>_x000D_
<div class="checkboxes">_x000D_
    <input type="checkbox" name="check" id="check" /> Check Box 1_x000D_
    <br/>_x000D_
    <input type="checkbox" name="check" id="check" /> Check Box 2_x000D_
    <br/>_x000D_
    <input type="checkbox" name="check" id="check" /> Check Box 3_x000D_
    <br/>_x000D_
    <input type="checkbox" name="check" id="check" /> Check Box 4_x000D_
</div>
_x000D_
_x000D_
_x000D_

Try this Demo Link

There is also another short way to do this, checkout below example. In this example check/uncheck all checkbox is checked or not if checked then all wiil be checked and if not all will be uncheck

_x000D_
_x000D_
$("#check_uncheck").change(function() {_x000D_
    $(".checkboxes input:checkbox").prop("checked",$(this).is(':checked'));_x000D_
})
_x000D_
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>_x000D_
    <input type="checkbox" name="check_uncheck" id="check_uncheck" /> Check All/Uncheck All_x000D_
    <br/>_x000D_
    <br/>_x000D_
    <div class="checkboxes">_x000D_
        <input type="checkbox" name="check" id="check" /> Check Box 1_x000D_
        <br/>_x000D_
        <input type="checkbox" name="check" id="check" /> Check Box 2_x000D_
        <br/>_x000D_
        <input type="checkbox" name="check" id="check" /> Check Box 3_x000D_
        <br/>_x000D_
        <input type="checkbox" name="check" id="check" /> Check Box 4_x000D_
    </div>
_x000D_
_x000D_
_x000D_

What causes a SIGSEGV

SigSegV means a signal for memory access violation, trying to read or write from/to a memory area that your process does not have access to. These are not C or C++ exceptions and you can’t catch signals. It’s possible indeed to write a signal handler that ignores the problem and allows continued execution of your unstable program in undefined state, but it should be obvious that this is a very bad idea.

Most of the time this is because of a bug in the program. The memory address given can help debug what’s the problem (if it’s close to zero then it’s likely a null pointer dereference, if the address is something like 0xadcedfe then it’s intentional safeguard or a debug check, etc.)

One way of “catching” the signal is to run your stuff in a separate child process that can then abruptly terminate without taking your main process down with it. Finding the root cause and fixing it is obviously preferred over workarounds like this.

How to monitor Java memory usage?

As has been suggested, try VisualVM to get a basic view.

You can also use Eclipse MAT, to do a more detailed memory analysis.

It's ok to do a System.gc() as long as you dont depend on it, for the correctness of your program.

In Java, can you modify a List while iterating through it?

Use Java 8's removeIf(),

To remove safely,

letters.removeIf(x -> !x.equals("A"));

How to fix "could not find a base address that matches schema http"... in WCF

The solution is to define a custom binding inside your Web.Config file and set the security mode to "Transport". Then you just need to use the bindingConfiguration property inside your endpoint definition to point to your custom binding.

See here: Scott's Blog: WCF Bindings Needed For HTTPS

SQL left join vs multiple tables on FROM line?

The JOIN syntax keeps conditions near the table they apply to. This is especially useful when you join a large amount of tables.

By the way, you can do an outer join with the first syntax too:

WHERE a.x = b.x(+)

Or

WHERE a.x *= b.x

Or

WHERE a.x = b.x or a.x not in (select x from b)

Breaking out of nested loops

If you're going to raise an exception, you might raise a StopIteration exception. That will at least make the intent obvious.

Are PostgreSQL column names case-sensitive?

if use JPA I recommend change to lowercase schema, table and column names, you can use next intructions for help you:

select
    psat.schemaname,
    psat.relname,
    pa.attname,
    psat.relid
from
    pg_catalog.pg_stat_all_tables psat,
    pg_catalog.pg_attribute pa
where
    psat.relid = pa.attrelid

change schema name:

ALTER SCHEMA "XXXXX" RENAME TO xxxxx;

change table names:

ALTER TABLE xxxxx."AAAAA" RENAME TO aaaaa;

change column names:

ALTER TABLE xxxxx.aaaaa RENAME COLUMN "CCCCC" TO ccccc;

Python requests library how to pass Authorization header with single token

You can try something like this

r = requests.get(ENDPOINT, params=params, headers={'Authorization': 'Basic %s' %  API_KEY})

Sending and Receiving SMS and MMS in Android (pre Kit Kat Android 4.4)

There is not official api support which means that it is not documented for the public and the libraries may change at any time. I realize you don't want to leave the application but here's how you do it with an intent for anyone else wondering.

public void sendData(int num){
    String fileString = "..."; //put the location of the file here
    Intent mmsIntent = new Intent(Intent.ACTION_SEND);
    mmsIntent.putExtra("sms_body", "text");
    mmsIntent.putExtra("address", num);
    mmsIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(new File(fileString)));
    mmsIntent.setType("image/jpeg");
    startActivity(Intent.createChooser(mmsIntent, "Send"));

}

I haven't completely figured out how to do things like track the delivery of the message but this should get it sent.

You can be alerted to the receipt of mms the same way as sms. The intent filter on the receiver should look like this.

<intent-filter>
    <action android:name="android.provider.Telephony.WAP_PUSH_RECEIVED" />
    <data android:mimeType="application/vnd.wap.mms-message" />
</intent-filter>

To enable extensions, verify that they are enabled in those .ini files - Vagrant/Ubuntu/Magento 2.0.2

This was the fix for me when trying to install Laravel on a fresh WSL installation:

sudo apt-get install php7.2-gd

sudo apt-get install php7.2-intl

sudo apt-get install php7.2-xsl

sudo apt-get install php7.2-zip

Multidimensional Array [][] vs [,]

In the first instance you are trying to create what is called a jagged array.

double[][] ServicePoint = new double[10][9].

The above statement would have worked if it was defined like below.

double[][] ServicePoint = new double[10][]

what this means is you are creating an array of size 10 ,that can store 10 differently sized arrays inside it.In simple terms an Array of arrays.see the below image,which signifies a jagged array.

enter image description here

http://msdn.microsoft.com/en-us/library/2s05feca(v=vs.80).aspx

The second one is basically a two dimensional array and the syntax is correct and acceptable.

  double[,] ServicePoint = new double[10,9];//<-ok (2)

And to access or modify a two dimensional array you have to pass both the dimensions,but in your case you are passing just a single dimension,thats why the error

Correct usage would be

ServicePoint[0][2] ,Refers to an item on the first row ,third column.

Pictorial rep of your two dimensional array

enter image description here

How to launch an EXE from Web page (asp.net)

You can see how iTunes does it by using Fiddler to follow the action when using the link: http://phobos.apple.com/WebObjects/MZStore.woa/wa/viewPodcast?id=80028216

  1. It downloads a js file
  2. On windows: the js file determines if iTunes was installed on the computer or not: looks for an activeX browser component if IE, or a browser plugin if FF
  3. If iTunes is installed then the browser is redirected to an URL with a special transport: itms://...
  4. The browser invokes the handler (provided by the iTunes exe). This includes starting up the exe if it is not already running.
  5. iTunes exe uses the rest of the special url to show a specific page to the user.

Note that the exe, when installed, installed URL protocol handlers for "itms" transport with the browsers.

Not a simple engineering project to duplicate, but definitely do-able. If you go ahead with this, please consider making the relevant software open source.

Get current date in milliseconds

As mentioned before, [[NSDate date] timeIntervalSince1970] returns an NSTimeInterval, which is a duration in seconds, not milli-seconds.

You can visit https://currentmillis.com/ to see how you can get in the language you desire. Here is the list -

ActionScript    (new Date()).time
C++ std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()).count()
C#.NET  DateTimeOffset.UtcNow.ToUnixTimeMilliseconds()
Clojure (System/currentTimeMillis)
Excel / Google Sheets*  = (NOW() - CELL_WITH_TIMEZONE_OFFSET_IN_HOURS/24 - DATE(1970,1,1)) * 86400000
Go / Golang time.Now().UnixNano() / 1000000
Hive*   unix_timestamp() * 1000
Java / Groovy / Kotlin  System.currentTimeMillis()
Javascript  new Date().getTime()
MySQL*  UNIX_TIMESTAMP() * 1000
Objective-C (long long)([[NSDate date] timeIntervalSince1970] * 1000.0)
OCaml   (1000.0 *. Unix.gettimeofday ())
Oracle PL/SQL*  SELECT (SYSDATE - TO_DATE('01-01-1970 00:00:00', 'DD-MM-YYYY HH24:MI:SS')) * 24 * 60 * 60 * 1000 FROM DUAL
Perl    use Time::HiRes qw(gettimeofday); print gettimeofday;
PHP round(microtime(true) * 1000)
PostgreSQL  extract(epoch FROM now()) * 1000
Python  int(round(time.time() * 1000))
Qt  QDateTime::currentMSecsSinceEpoch()
R*  as.numeric(Sys.time()) * 1000
Ruby    (Time.now.to_f * 1000).floor
Scala   val timestamp: Long = System.currentTimeMillis
SQL Server  DATEDIFF(ms, '1970-01-01 00:00:00', GETUTCDATE())
SQLite* STRFTIME('%s', 'now') * 1000
Swift*  let currentTime = NSDate().timeIntervalSince1970 * 1000
VBScript / ASP  offsetInMillis = 60000 * GetTimeZoneOffset()
WScript.Echo DateDiff("s", "01/01/1970 00:00:00", Now()) * 1000 - offsetInMillis + Timer * 1000 mod 1000

For objective C I did something like below to print it -

long long mills = (long long)([[NSDate date] timeIntervalSince1970] * 1000.0);
 NSLog(@"Current date %lld", mills);

Hopw this helps.

Printing all variables value from a class

When accessing the field value, pass the instance rather than null.

Why not use code generation here? Eclipse, for example, will generate a reasoble toString implementation for you.

Laravel - Return json along with http status code

laravel 7.* You don't have to speicify JSON RESPONSE cause it's automatically converted it to JSON

return response(['Message'=>'Wrong Credintals'], 400);

How to SSH into Docker?

Notice: this answer promotes a tool I've written.

The selected answer here suggests to install an SSH server into every image. Conceptually this is not the right approach (https://docs.docker.com/articles/dockerfile_best-practices/).

I've created a containerized SSH server that you can 'stick' to any running container. This way you can create compositions with every container. The only requirement is that the container has bash.

The following example would start an SSH server exposed on port 2222 of the local machine.

$ docker run -d -p 2222:22 \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e CONTAINER=my-container -e AUTH_MECHANISM=noAuth \
  jeroenpeeters/docker-ssh

$ ssh -p 2222 localhost

For more pointers and documentation see: https://github.com/jeroenpeeters/docker-ssh

Not only does this defeat the idea of one process per container, it is also a cumbersome approach when using images from the Docker Hub since they often don't (and shouldn't) contain an SSH server.

How to convert a number to string and vice versa in C++

#include <iostream>
#include <string.h>
using namespace std;
int main() {
   string s="000101";
   cout<<s<<"\n";
   int a = stoi(s);
   cout<<a<<"\n";
   s=to_string(a);
   s+='1';
   cout<<s;
   return 0;
}

Output:

  • 000101
  • 101
  • 1011

SSRS the definition of the report is invalid

I just received this obscure message when trying to deploy a report from BIDS.

After a little hunting I found a more descriptive error by going into the Preview window.

Reading file line by line (with space) in Unix Shell scripting - Issue

Try this,

IFS=''
while read line
do
    echo $line
done < file.txt

EDIT:

From man bash

IFS - The Internal Field Separator that is used for word
splitting after expansion and to split lines into words
with  the  read  builtin  command. The default value is
``<space><tab><newline>''

Make a phone call programmatically

Merging the answers of @Cristian Radu and @Craig Mellon, and the comment from @joel.d, you should do:

NSURL *urlOption1 = [NSURL URLWithString:[@"telprompt://" stringByAppendingString:phone]];
NSURL *urlOption2 = [NSURL URLWithString:[@"tel://" stringByAppendingString:phone]];
NSURL *targetURL = nil;

if ([UIApplication.sharedApplication canOpenURL:urlOption1]) {
    targetURL = urlOption1;
} else if ([UIApplication.sharedApplication canOpenURL:urlOption2]) {
    targetURL = urlOption2;
}

if (targetURL) {
    if (@available(iOS 10.0, *)) {
        [UIApplication.sharedApplication openURL:targetURL options:@{} completionHandler:nil];
    } else {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
        [UIApplication.sharedApplication openURL:targetURL];
#pragma clang diagnostic pop
    }
} 

This will first try to use the "telprompt://" URL, and if that fails, it will use the "tel://" URL. If both fails, you're trying to place a phone call on an iPad or iPod Touch.

Swift Version :

let phone = mymobileNO.titleLabel.text
let phoneUrl = URL(string: "telprompt://\(phone)"
let phoneFallbackUrl = URL(string: "tel://\(phone)"
if(phoneUrl != nil && UIApplication.shared.canOpenUrl(phoneUrl!)) {
  UIApplication.shared.open(phoneUrl!, options:[String:Any]()) { (success) in
    if(!success) {
      // Show an error message: Failed opening the url
    }
  }
} else if(phoneFallbackUrl != nil && UIApplication.shared.canOpenUrl(phoneFallbackUrl!)) {
  UIApplication.shared.open(phoneFallbackUrl!, options:[String:Any]()) { (success) in
    if(!success) {
      // Show an error message: Failed opening the url
    }
  }
} else {
    // Show an error message: Your device can not do phone calls.
}

how to fix stream_socket_enable_crypto(): SSL operation failed with code 1

Editor's note: disabling SSL verification has security implications. Without verification of the authenticity of SSL/HTTPS connections, a malicious attacker can impersonate a trusted endpoint such as Gmail, and you'll be vulnerable to a Man-in-the-Middle Attack.

Be sure you fully understand the security issues before using this as a solution.

Easy fix for this might be editing config/mail.php and turning off TLS

'encryption' => env('MAIL_ENCRYPTION', ''), //'tls'),

Basically by doing this

$options['ssl']['verify_peer'] = FALSE;
$options['ssl']['verify_peer_name'] = FALSE;

You should loose security also, but in first option there is no need to dive into Vendor's code.

What is Node.js?

The closures are a way to execute code in the context it was created in.

What this means for concurency is that you can define variables, then initiate a nonblocking I/O function, and send it an anonymous function for its callback.

When the task is complete, the callback function will execute in the context with the variables, this is the closure.

The reason closures are so good for writing applications with nonblocking I/O is that it's very easy to manage the context of functions executing asynchronously.

send mail from linux terminal in one line

Sending Simple Mail:

$ mail -s "test message from centos" [email protected]
hello from centos linux command line

Ctrl+D to finish

How to use ng-if to test if a variable is defined

You can still use angular.isDefined()

You just need to set

$rootScope.angular = angular;

in the "run" phase.

See update plunkr: http://plnkr.co/edit/h4ET5dJt3e12MUAXy1mS?p=preview

node.js hash string?

The crypto module makes this very easy.

Setup:

// import crypto from 'crypto';
const crypto = require('crypto');

const sha256 = x => crypto.createHash('sha256').update(x, 'utf8').digest('hex');

Usage:

sha256('Hello, world. ');

Chrome javascript debugger breakpoints don't do anything?

So, in addition to Adam Rackis' answer, if you have errors in your javascript file above the breakpoint, you won't reach it regardless if you flag it, or put in debugger;.

Here's an example:

if (nonExistentVar === "something") {
  console.log("this won't happen as the above errors out");
}
debugger;
console.log("this won't print either")

curl -GET and -X GET

The use of -X [WHATEVER] merely changes the request's method string used in the HTTP request. This is easier to understand with two examples — one with -X [WHATEVER] and one without — and the associated HTTP request headers for each:

# curl -XPANTS -o nul -v http://neverssl.com/
* Connected to neverssl.com (13.224.86.126) port 80 (#0)
> PANTS / HTTP/1.1
> Host: neverssl.com
> User-Agent: curl/7.42.0
> Accept: */*

# curl -o nul -v http://neverssl.com/
* Connected to neverssl.com (13.33.50.167) port 80 (#0)
> GET / HTTP/1.1
> Host: neverssl.com
> User-Agent: curl/7.42.0
> Accept: */*

Getting the class name of an instance?

To get instance classname:

type(instance).__name__

or

instance.__class__.__name__

both are the same

Create parameterized VIEW in SQL Server 2008

no. You can use UDF in which you can pass parameters.

How to save CSS changes of Styles panel of Chrome Developer Tools?

New versions of Chrome have a feature called workspaces which addresses this issue. You can define which paths on your webserver correspond to which paths on your system, then edit and save with just ctrl-s.

See: http://www.html5rocks.com/en/tutorials/developertools/revolutions2013/

MySQL Like multiple values

Don't forget to use parenthesis if you use this function after an AND parameter

Like this:

WHERE id=123 and(interests LIKE '%sports%' OR interests LIKE '%pub%')

Java: How to Indent XML Generated by Transformer

The following code is working for me with Java 7. I set the indent (yes) and indent-amount (2) on the transformer (not the transformer factory) to get it working.

TransformerFactory tf = TransformerFactory.newInstance();
Transformer t = tf.newTransformer();
t.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
t.setOutputProperty(OutputKeys.INDENT, "yes");
t.transform(source, result);

@mabac's solution to set the attribute didn't work for me, but @lapo's comment proved helpful.

How to sign in kubernetes dashboard?

Download https://raw.githubusercontent.com/kubernetes/dashboard/master/src/deploy/alternative/kubernetes-dashboard.yaml

add

type: NodePort for the Service

And then run this command:

kubectl apply -f kubernetes-dashboard.yaml

Find the exposed port with the command :

kubectl get services -n kube-system

You should be able to get the dashboard at http://hostname:exposedport/ with no authentication

Save base64 string as PDF at client side with JavaScript

You can create an anchor like the one showed below to download the base64 pdf:

<a download=pdfTitle href=pdfData title='Download pdf document' />

where pdfData is your base64 encoded pdf like "data:application/pdf;base64,JVBERi0xLjQKJcOkw7zDtsOfCjIgMCBvYmoKPDwvTGVuZ3RoIDMgMCBSL0ZpbHRlci9GbGF0ZURlY29kZT4+CnN0cmVhbQp4nO1cyY4ktxG911fUWUC3kjsTaBTQ1Ytg32QN4IPgk23JMDQ2LB/0+2YsZAQzmZk1PSPIEB..."

How do I read a resource file from a Java jar file?

You don't say if this is a desktop or web app. I would use the getResourceAsStream() method from an appropriate ClassLoader if it's a desktop or the Context if it's a web app.

Turn a string into a valid filename?

This is the solution I ultimately used:

import unicodedata

validFilenameChars = "-_.() %s%s" % (string.ascii_letters, string.digits)

def removeDisallowedFilenameChars(filename):
    cleanedFilename = unicodedata.normalize('NFKD', filename).encode('ASCII', 'ignore')
    return ''.join(c for c in cleanedFilename if c in validFilenameChars)

The unicodedata.normalize call replaces accented characters with the unaccented equivalent, which is better than simply stripping them out. After that all disallowed characters are removed.

My solution doesn't prepend a known string to avoid possible disallowed filenames, because I know they can't occur given my particular filename format. A more general solution would need to do so.

TypeError: document.getElementbyId is not a function

Case sensitive: document.getElementById (notice the capital B).

How to specify the actual x axis values to plot as x axis ticks in R

In case of plotting time series, the command ts.plot requires a different argument than xaxt="n"

require(graphics)
ts.plot(ldeaths, mdeaths, xlab="year", ylab="deaths", lty=c(1:2), gpars=list(xaxt="n"))
axis(1, at = seq(1974, 1980, by = 2))