Programs & Examples On #Jpcap

Jpcap is a Java Library which enables you to Send and capture Packets.

What is the difference between Bootstrap .container and .container-fluid classes?

.container has a max width pixel value, whereas .container-fluid is max-width 100%.

.container-fluid continuously resizes as you change the width of your window/browser by any amount.

.container resizes in chunks at several certain widths, controlled by media queries (technically we can say it’s “fixed width” because pixels values are specified, but if you stop there, people may get the impression that it can’t change size – i.e. not responsive.)

CSS Flex Box Layout: full-width row and columns

You've almost done it. However setting flex: 0 0 <basis> declaration to the columns would prevent them from growing/shrinking; And the <basis> parameter would define the width of columns.

In addition, you could use CSS3 calc() expression to specify the height of columns with the respect to the height of the header.

#productShowcaseTitle {
  flex: 0 0 100%; /* Let it fill the entire space horizontally */
  height: 100px;
}

#productShowcaseDetail,
#productShowcaseThumbnailContainer {
  height: calc(100% - 100px); /* excluding the height of the header */
}

_x000D_
_x000D_
#productShowcaseContainer {_x000D_
  display: flex;_x000D_
  flex-flow: row wrap;_x000D_
_x000D_
  height: 600px;_x000D_
  width: 580px;_x000D_
}_x000D_
_x000D_
#productShowcaseTitle {_x000D_
  flex: 0 0 100%; /* Let it fill the entire space horizontally */_x000D_
  height: 100px;_x000D_
  background-color: silver;_x000D_
}_x000D_
_x000D_
#productShowcaseDetail {_x000D_
  flex: 0 0 66%; /* ~ 2 * 33.33% */_x000D_
  height: calc(100% - 100px); /* excluding the height of the header */_x000D_
  background-color: lightgray;_x000D_
}_x000D_
_x000D_
#productShowcaseThumbnailContainer {_x000D_
  flex: 0 0 34%;  /* ~ 33.33% */_x000D_
  height: calc(100% - 100px); /* excluding the height of the header */_x000D_
  background-color: black;_x000D_
}
_x000D_
<div id="productShowcaseContainer">_x000D_
  <div id="productShowcaseTitle"></div>_x000D_
  <div id="productShowcaseDetail"></div>_x000D_
  <div id="productShowcaseThumbnailContainer"></div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

(Vendor prefixes omitted due to brevity)


Alternatively, if you could change your markup e.g. wrapping the columns by an additional <div> element, it would be achieved without using calc() as follows:

<div class="contentContainer"> <!-- Added wrapper -->
    <div id="productShowcaseDetail"></div>
    <div id="productShowcaseThumbnailContainer"></div>
</div>
#productShowcaseContainer {
  display: flex;
  flex-direction: column;
  height: 600px; width: 580px;
}

.contentContainer { display: flex; flex: 1; }
#productShowcaseDetail { flex: 3; }
#productShowcaseThumbnailContainer { flex: 2; }

_x000D_
_x000D_
#productShowcaseContainer {_x000D_
  display: flex;_x000D_
  flex-direction: column;_x000D_
_x000D_
  height: 600px;_x000D_
  width: 580px;_x000D_
}_x000D_
_x000D_
.contentContainer {_x000D_
  display: flex;_x000D_
  flex: 1;_x000D_
}_x000D_
_x000D_
#productShowcaseTitle {_x000D_
  height: 100px;_x000D_
  background-color: silver;_x000D_
}_x000D_
_x000D_
#productShowcaseDetail {_x000D_
  flex: 3;_x000D_
  background-color: lightgray;_x000D_
}_x000D_
_x000D_
#productShowcaseThumbnailContainer {_x000D_
  flex: 2;_x000D_
  background-color: black;_x000D_
}
_x000D_
<div id="productShowcaseContainer">_x000D_
  <div id="productShowcaseTitle"></div>_x000D_
_x000D_
  <div class="contentContainer"> <!-- Added wrapper -->_x000D_
    <div id="productShowcaseDetail"></div>_x000D_
    <div id="productShowcaseThumbnailContainer"></div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

(Vendor prefixes omitted due to brevity)

Import module from subfolder

There's no need to mess with your PYTHONPATH or sys.path here.

To properly use absolute imports in a package you should include the "root" packagename as well, e.g.:

from dirFoo.dirFoo1.foo1 import Foo1
from dirFoo.dirFoo2.foo2 import Foo2

Or you can use relative imports:

from .dirfoo1.foo1 import Foo1
from .dirfoo2.foo2 import Foo2

ASP.NET MVC - Attaching an entity of type 'MODELNAME' failed because another entity of the same type already has the same primary key value

In my case , I had wrote really two times an entity of same type . So I delete it and all things work correctly

Maven - Failed to execute goal org.apache.maven.plugins:maven-clean-plugin:2.4.1:clean

Reason and solution-

Everything happens for a reason :)

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-clean-plugin:3.1.0:clean (default-clean) on project

  • The reason of this problem is that the target folder is already in use. That means any jar or any war or any application is using that target folder

Solution- 1) Check the war and jar (also check jar if any running in background), terminate it.

2) if u have opened command prompt (cmd), and are using that path to execute the jar, close it or change the path in cmd. This was the reason in my case. Do check this.

Once u do this , u would be able to delete the contents of the target folder and and can also perform maven clean and maven install.

Facebook page automatic "like" URL (for QR Code)

I'm not an attorney, but clicking the like button without the express permission of a facebook user might be a violation of facebook policy. You should have your corporate attorney check out the facebook policy.

You should encode the url to a page with a like button, so when scanned by the phone, it opens up a browser window to the like page, where now the user has the option to like it or not.

Is there a query language for JSON?

The built-in array.filter() method makes most of these so-called javascript query libraries obsolete

You can put as many conditions inside the delegate as you can imagine: simple comparison, startsWith, etc. I haven't tested but you could probably nest filters too for querying inner collections.

Remove all of x axis labels in ggplot

You have to set to element_blank() in theme() elements you need to remove

ggplot(data = diamonds, mapping = aes(x = clarity)) + geom_bar(aes(fill = cut))+
  theme(axis.title.x=element_blank(),
        axis.text.x=element_blank(),
        axis.ticks.x=element_blank())

Can I get JSON to load into an OrderedDict?

Some great news! Since version 3.6 the cPython implementation has preserved the insertion order of dictionaries (https://mail.python.org/pipermail/python-dev/2016-September/146327.html). This means that the json library is now order preserving by default. Observe the difference in behaviour between python 3.5 and 3.6. The code:

import json
data = json.loads('{"foo":1, "bar":2, "fiddle":{"bar":2, "foo":1}}')
print(json.dumps(data, indent=4))

In py3.5 the resulting order is undefined:

{
    "fiddle": {
        "bar": 2,
        "foo": 1
    },
    "bar": 2,
    "foo": 1
}

In the cPython implementation of python 3.6:

{
    "foo": 1,
    "bar": 2,
    "fiddle": {
        "bar": 2,
        "foo": 1
    }
}

The really great news is that this has become a language specification as of python 3.7 (as opposed to an implementation detail of cPython 3.6+): https://mail.python.org/pipermail/python-dev/2017-December/151283.html

So the answer to your question now becomes: upgrade to python 3.6! :)

Editing the date formatting of x-axis tick labels in matplotlib

In short:

import matplotlib.dates as mdates
myFmt = mdates.DateFormatter('%d')
ax.xaxis.set_major_formatter(myFmt)

Many examples on the matplotlib website. The one I most commonly use is here

Loop through JSON object List

It's close! Try this:

for (var prop in result) {
    if (result.hasOwnProperty(prop)) {
        alert(result[prop]);
    }
}

Update:

If your result is truly is an array of one object, then you might have to do this:

for (var prop in result[0]) {
    if (result[0].hasOwnProperty(prop)) {
        alert(result[0][prop]);
    }
}

Or if you want to loop through each result in the array if there are more, try:

for (var i = 0; i < results.length; i++) {
    for (var prop in result[i]) {
        if (result[i].hasOwnProperty(prop)) {
            alert(result[i][prop]);
        }
    }
}

Explanation of <script type = "text/template"> ... </script>

<script type = “text/template”> … </script> is obsolete. Use <template> tag instead.

DataRow: Select cell value by a given column name

Hint

DataTable table = new DataTable();
table.Columns.Add("Column#1", typeof(int));
table.Columns.Add("Column#2", typeof(string));
table.Rows.Add(5, "Cell1-1");
table.Rows.Add(130, "Cell2-2");

EDIT: Added more

string cellValue = table.Rows[0].GetCellValueByName<string>("Column#2");

public static class DataRowExtensions
{
    public static T GetCellValueByName<T>(this DataRow row, string columnName)
    {
        int index = row.Table.Columns.IndexOf(columnName);
        return (index < 0 || index > row.ItemArray.Count()) 
                  ? default(T) 
                  : (T) row[index];        
    }
}

Why is Chrome showing a "Please Fill Out this Field" tooltip on empty fields?

You need to add the attribute "formnovalidate" to the control that is triggering the browser validation, e.g.:

<input type="image" id="fblogin" formnovalidate src="/images/facebook_connect.png">

Restart node upon changing a file

Various NPM packages are available to make this task easy.

For Development

For Production (with extended functionality such as clustering, remote deploy etc.)

Comparison between Forever, pm2 and StrongLoop can be found on StrongLoop's website.

How to start/stop/restart a thread in Java?

Review java.lang.Thread.

To start or restart (once a thread is stopped, you can't restart that same thread, but it doesn't matter; just create a new Thread instance):

// Create your Runnable instance
Task task = new Task(...);

// Start a thread and run your Runnable
Thread t = new Thread(task);

To stop it, have a method on your Task instance that sets a flag to tell the run method to exit; returning from run exits the thread. If your calling code needs to know the thread really has stopped before it returns, you can use join:

// Tell Task to stop
task.setStopFlag(true);

// Wait for it to do so
t.join();

Regarding restarting: Even though a Thread can't be restarted, you can reuse your Runnable instance with a new thread if it has state and such you want to keep; that comes to the same thing. Just make sure your Runnable is designed to allow multiple calls to run.

How to make sure that string is valid JSON using JSON.NET

I'm using this one:

  internal static bool IsValidJson(string data)
  {
     data = data.Trim();
     try
     {
        if (data.StartsWith("{") && data.EndsWith("}"))
        {
           JToken.Parse(data);
        }
        else if (data.StartsWith("[") && data.EndsWith("]"))
        {
           JArray.Parse(data);
        }
        else
        {
           return false;
        }
        return true;
     }
     catch
     {
        return false;
     }
  }

How to change the height of a div dynamically based on another div using css?

<!DOCTYPE html>
<html lang="en">
<head>
<!-- Here is the Pakka codes for making the height of a division equal to another dynamically - M C Jain, Chartered Accountant -->

<script language="javascript">
function make_equal_heights()
{


if ((document.getElementById('div_A').offsetHeight) > (document.getElementById('div_B').offsetHeight) ) 
{ 
document.getElementById('div_B').style.height = (document.getElementById('div_A').offsetHeight) + "px";
} 
else 
{ 
document.getElementById('div_A').style.height = (document.getElementById('div_B').offsetHeight) + "px"
}


}
</script>

</head>

<body style="margin:50px;"  onload="make_equal_heights()"> 

<div  id="div_A"  style="height:200px; width:150px; margin-top:22px;
                        background-color:lightblue;float:left;">DIVISION A</div><br>

<div  id="div_B"  style="height:150px; width:150px; margin-left:12px;
                        background-color: blue; float:left; ">DIVISION B</div>

</body>
</html>

How can I get System variable value in Java?

As mentioned by sombody above, restarting eclipse worked for me for the user defined environment variable. After I restart eclipse IDE, System.getenv() is picking up my environment variable.

Problem in running .net framework 4.0 website on iis 7.0

Go to IIS manager and click on the server name. Then click on the "ISAPI and CGI Restrictions" icon under the IIS header. Change ASP.NET 4.0 from "Not Allowed" to "Allowed".

Why are only a few video games written in Java?

Game marketing is a commercial process; publishers want quantifiable low-risk returns on their investment. As a consequence, the focus is usually on technology gimmicks (with exceptions) that consumers will buy to produce reliable return - these tend to be superficial visual effects such as lens glare or higher resolution. These effects are reliable because they simply use increases in processing power - they exploit the hardware/Moore's law increases. this implies using C/C++ - java is usually too abstracted from the hardware to exploit these benefits.

How can I get device ID for Admob

  • Is your app published on Play store -- with live ads:

If your app is on Play store showing live ads -- you can't use live ads for testing -- add your device ID in code to get test ads from Admob on your real device. Never use live ads during development or testing.

To get real device ID in logcat,

  1. Connect your device in USB debug mode to Android Studio

USB debug mode(Developer option)

  1. Open any app on your device which shows live ads from Admob: On the connected device, if you have your app downloaded from play store(showing live ads) open that app or else open any other app that shows live Admob ads. Your device should have an internet connection.

  2. Filter the logcat with 'device' as shown below to get test device

Test Device ID in logcat

Read Admob ad testing on device - device IDs can change for more

The program can't start because cygwin1.dll is missing... in Eclipse CDT

This error message means that Windows isn't able to find "cygwin1.dll". The Programs that the Cygwin gcc create depend on this DLL. The file is part of cygwin , so most likely it's located in C:\cygwin\bin. To fix the problem all you have to do is add C:\cygwin\bin (or the location where cygwin1.dll can be found) to your system path. Alternatively you can copy cygwin1.dll into your Windows directory.

There is a nice tool called DependencyWalker that you can download from http://www.dependencywalker.com . You can use it to check dependencies of executables, so if you inspect your generated program it tells you which dependencies are missing and which are resolved.

Eclipse - Unable to install breakpoint due to missing line number attributes

This worked for me:

  1. Under Window --> Preferences --> Java --> Compiler --> Classfile Generation, all options have to be to True.
  2. Made debug="true" in the build.xml <javac> task.
  3. Deploy application in the tomcat by the war generated by ant
  4. Restarted the Tomcat in Debug mode

$on and $broadcast in angular

//Your broadcast in service

(function () { 
    angular.module('appModule').factory('AppService', function ($rootScope, $timeout) {

    function refreshData() {  
        $timeout(function() {         
            $rootScope.$broadcast('refreshData');
        }, 0, true);      
    }

    return {           
        RefreshData: refreshData
    };
}); }());

//Controller Implementation
 (function () {
    angular.module('appModule').controller('AppController', function ($rootScope, $scope, $timeout, AppService) {            

       //Removes Listeners before adding them 
       //This line will solve the problem for multiple broadcast call                             
       $scope.$$listeners['refreshData'] = [];

       $scope.$on('refreshData', function() {                                                    
          $scope.showData();             
       });

       $scope.onSaveDataComplete = function() { 
         AppService.RefreshData();
       };
    }); }());

Capitalize first letter. MySQL

This should work nicely:

UPDATE tb_Company SET CompanyIndustry = 
CONCAT(UPPER(LEFT(CompanyIndustry, 1)), SUBSTRING(CompanyIndustry, 2))

Laravel Eloquent Join vs Inner Join?

Probably not what you want to hear, but a "feeds" table would be a great middleman for this sort of transaction, giving you a denormalized way of pivoting to all these data with a polymorphic relationship.

You could build it like this:

<?php

Schema::create('feeds', function($table) {
    $table->increments('id');
    $table->timestamps();
    $table->unsignedInteger('user_id');
    $table->foreign('user_id')->references('id')->on('users')->onDelete('cascade');
    $table->morphs('target'); 
});

Build the feed model like so:

<?php

class Feed extends Eloquent
{
    protected $fillable = ['user_id', 'target_type', 'target_id'];

    public function user()
    {
        return $this->belongsTo('User');
    }

    public function target()
    {
        return $this->morphTo();
    }
}

Then keep it up to date with something like:

<?php

Vote::created(function(Vote $vote) {
    $target_type = 'Vote';
    $target_id   = $vote->id;
    $user_id     = $vote->user_id;

    Feed::create(compact('target_type', 'target_id', 'user_id'));
});

You could make the above much more generic/robust—this is just for demonstration purposes.

At this point, your feed items are really easy to retrieve all at once:

<?php

Feed::whereIn('user_id', $my_friend_ids)
    ->with('user', 'target')
    ->orderBy('created_at', 'desc')
    ->get();

How to call a web service from jQuery

I blogged about how to consume a WCF service using jQuery:

http://yoavniran.wordpress.com/2009/08/02/creating-a-webservice-proxy-with-jquery/

The post shows how to create a service proxy straight up in javascript.

libpng warning: iCCP: known incorrect sRGB profile

some background info on this:

Some changes in libpng version 1.6+ cause it to issue a warning or even not work correctly with the original HP/MS sRGB profile, leading to the following stderr: libpng warning: iCCP: known incorrect sRGB profile The old profile uses a D50 whitepoint, where D65 is standard. This profile is not uncommon, being used by Adobe Photoshop, although it was not embedded into images by default.

(source: https://wiki.archlinux.org/index.php/Libpng_errors)

Error detection in some chunks has improved; in particular the iCCP chunk reader now does pretty complete validation of the basic format. Some bad profiles that were previously accepted are now rejected, in particular the very old broken Microsoft/HP sRGB profile. The PNG spec requirement that only grayscale profiles may appear in images with color type 0 or 4 and that even if the image only contains gray pixels, only RGB profiles may appear in images with color type 2, 3, or 6, is now enforced. The sRGB chunk is allowed to appear in images with any color type.

(source: https://forum.qt.io/topic/58638/solved-libpng-warning-iccp-known-incorrect-srgb-profile-drive-me-nuts/16)

Finding repeated words on a string and counting the repetitions

import java.util.HashMap;
import java.util.Scanner;
public class class1 {
public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    String inpStr = in.nextLine();
    int key;

    HashMap<String,Integer> hm = new HashMap<String,Integer>();
    String[] strArr = inpStr.split(" ");

    for(int i=0;i<strArr.length;i++){
        if(hm.containsKey(strArr[i])){
            key = hm.get(strArr[i]);
            hm.put(strArr[i],key+1);

        }
        else{
            hm.put(strArr[i],1);
        }   
    }
    System.out.println(hm);
}

}

Getting list of parameter names inside python function

If you also want the values you can use the inspect module

import inspect

def func(a, b, c):
    frame = inspect.currentframe()
    args, _, _, values = inspect.getargvalues(frame)
    print 'function name "%s"' % inspect.getframeinfo(frame)[2]
    for i in args:
        print "    %s = %s" % (i, values[i])
    return [(i, values[i]) for i in args]

>>> func(1, 2, 3)
function name "func"
    a = 1
    b = 2
    c = 3
[('a', 1), ('b', 2), ('c', 3)]

Align <div> elements side by side

keep it simple

<div align="center">
<div style="display: inline-block"> <img src="img1.png"> </div>
<div style="display: inline-block"> <img src="img2.png"> </div>
</div>

Generate random string/characters in JavaScript

Put the characters as the thisArg in the map function will create a "one-liner":

Array.apply(null, Array(5))
.map(function(){ 
    return this[Math.floor(Math.random()*this.length)];
}, "abcdefghijklmnopqrstuvwxyz")
.join('');

combining results of two select statements

Probably you use Microsoft SQL Server which support Common Table Expressions (CTE) (see http://msdn.microsoft.com/en-us/library/ms190766.aspx) which are very friendly for query optimization. So I suggest you my favor construction:

WITH GetNumberOfPlans(Id,NumberOfPlans) AS (
    SELECT tableA.Id, COUNT(tableC.Id)
    FROM tableC
        RIGHT OUTER JOIN tableA ON tableC.tableAId = tableA.Id
    GROUP BY tableA.Id
),GetUserInformation(Id,Name,Owner,ImageUrl,
                     CompanyImageUrl,NumberOfUsers) AS (
    SELECT tableA.Id, tableA.Name, tableB.Username AS Owner, tableB.ImageUrl,
        tableB.CompanyImageUrl,COUNT(tableD.UserId),p.NumberOfPlans
    FROM tableA
        INNER JOIN tableB ON tableB.Id = tableA.Owner
        RIGHT OUTER JOIN tableD ON tableD.tableAId = tableA.Id
    GROUP BY tableA.Name, tableB.Username, tableB.ImageUrl, tableB.CompanyImageUrl
)
SELECT u.Id,u.Name,u.Owner,u.ImageUrl,u.CompanyImageUrl
    ,u.NumberOfUsers,p.NumberOfPlans
FROM GetUserInformation AS u
    INNER JOIN GetNumberOfPlans AS p ON p.Id=u.Id

After some experiences with CTE you will be find very easy to write code using CTE and you will be happy with the performance.

Error checking for NULL in VBScript

I will just add a blank ("") to the end of the variable and do the comparison. Something like below should work even when that variable is null. You can also trim the variable just in case of spaces.

If provider & "" <> "" Then 
    url = url & "&provider=" & provider 
End if

Chrome Dev Tools - Modify javascript and reload

Yes, just open the "Source" Tab in the dev-tools and navigate to the script you want to change . Make your adjustments directly in the dev tools window and then hit ctrl+s to save the script - know the new js will be used until you refresh the whole page.

Convert Unix timestamp into human readable date using MySQL

Need a unix timestamp in a specific timezone?

Here's a one liner if you have quick access to the mysql cli:

mysql> select convert_tz(from_unixtime(1467095851), 'UTC', 'MST') as 'local time';

+---------------------+
| local time          |
+---------------------+
| 2016-06-27 23:37:31 |
+---------------------+

Replace 'MST' with your desired timezone. I live in Arizona thus the conversion from UTC to MST.

How do you get the current page number of a ViewPager for Android?

The setOnPageChangeListener() method is deprecated. Use addOnPageChangeListener(OnPageChangeListener) instead.

You can use OnPageChangeListener and getting the position inside onPageSelected() method, this is an example:

   viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

        }

        @Override
        public void onPageSelected(int position) {
            Log.d(TAG, "my position is : " + position); 
        }

        @Override
        public void onPageScrollStateChanged(int state) {

        }
    });

Or just use getCurrentItem() to get the real position:

viewPager.getCurrentItem();

CSS fixed width in a span

In an ideal world you'd achieve this simply using the following css

<style type="text/css">

span {
  display: inline-block;
  width: 50px;
}

</style>

This works on all browsers apart from FF2 and below.

Firefox 2 and lower don't support this value. You can use -moz-inline-box, but be aware that it's not the same as inline-block, and it may not work as you expect in some situations.

Quote taken from quirksmode

Copy file(s) from one project to another using post build event...VS2010

xcopy "$(TargetDir)*$(TargetExt)" "$(SolutionDir)\Scripts\MigrationScripts\Library\" /F /R /Y /I

/F – Displays full source & target file names

/R – This will overwrite read-only files

/Y – Suppresses prompting to overwrite an existing file(s)

/I – Assumes that destination is directory (but must ends with )

A little trick – in target you must end with character \ to tell xcopy that target is directory and not file!

String Comparison in Java

Comparing sequencially the letters that have the same position against each other.. more like how you order words in a dictionary

Flash CS4 refuses to let go

Try deleting your ASO files.

ASO files are cached compiled versions of your class files. Although the IDE is a lot better at letting go of old caches when changes are made, sometimes you have to manually delete them. To delete ASO files: Control>Delete ASO Files.

This is also the cause of the "I-am-not-seeing-my-changes-so-let-me-add-a-trace-now-everything-works" bug that was introduced in CS3.

Val and Var in Kotlin

val - Immutable(once initialized can't be reassigned)

var - Mutable(can able to change value)

Example

in Kotlin - val n = 20 & var n = 20

In Java - final int n = 20; & int n = 20;

How to retrieve JSON Data Array from ExtJS Store

If you want to get the data exactly like what you get by Writer (for example ignoring fields with persist:false config), use the following code (Note: I tested it in Ext 5.1)

  var arr = [];   

    this.store.each(function (record) {
        arr.push(this.store.getProxy().getWriter().getRecordData(record))
    });  

How to change Angular CLI favicon

  1. Remove your existing favicon.ico
  2. Add new icon into the src folder with name as "favico.ico"
  3. Clear Cache in your browser.

The icon does not reflect only because of your browser cache. Sometimes try restarting the application

Putting HTML inside Html.ActionLink(), plus No Link Text?

It's very simple.

If you want to have something like a glyphicon icon and then "Wish List",

<span class="glyphicon-heart"></span> @Html.ActionLink("Wish List (0)", "Index", "Home")

jQuery animate backgroundColor

If you wan't to animate your background using only core jQuery functionality, try this:

jQuery(".usercontent").mouseover(function() {
      jQuery(".usercontent").animate({backgroundColor:'red'}, 'fast', 'linear', function() {
            jQuery(this).animate({
                backgroundColor: 'white'
            }, 'normal', 'linear', function() {
                jQuery(this).css({'background':'none', backgroundColor : ''});
            });
        });

CSV parsing in Java - working example..?

I agree with @Brian Clapper. I have used SuperCSV as a parser though I've had mixed results. I enjoy the versatility of it, but there are some situations within my own csv files for which I have not been able to reconcile "yet". I have faith in this product and would recommend it overall--I'm just missing something simple, no doubt, that I'm doing in my own implementation.

SuperCSV can parse the columns into various formats, do edits on the columns, etc. It's worth taking a look-see. It has examples as well, and easy to follow.

The one/only limitation I'm having is catching an 'empty' column and parsing it into an Integer or maybe a blank, etc. I'm getting null-pointer errors, but javadocs suggest each cellProcessor checks for nulls first. So, I'm blaming myself first, for now. :-)

Anyway, take a look at SuperCSV. http://supercsv.sourceforge.net/

How to concatenate columns in a Postgres SELECT?

PHP's Laravel framework, I am using search first_name, last_name Fields consider like Full Name Search

Using || symbol Or concat_ws(), concat() methods

$names = str_replace(" ", "", $searchKey);                               
$customers = Customer::where('organization_id',$this->user->organization_id)
             ->where(function ($q) use ($searchKey, $names) {
                 $q->orWhere('phone_number', 'ilike', "%{$searchKey}%"); 
                 $q->orWhere('email', 'ilike', "%{$searchKey}%");
                 $q->orWhereRaw('(first_name || last_name) LIKE ? ', '%' . $names. '%');
    })->orderBy('created_at','desc')->paginate(20);

This worked charm!!!

Saving any file to in the database, just convert it to a byte array?

I'll describe the way I've stored files, in SQL Server and Oracle. It largely depends on how you are getting the file, in the first place, as to how you will get its contents, and it depends on which database you are using for the content in which you will store it for how you will store it. These are 2 separate database examples with 2 separate methods of getting the file that I used.

SQL Server

Short answer: I used a base64 byte string I converted to a byte[] and store in a varbinary(max) field.

Long answer:

Say you're uploading via a website, so you're using an <input id="myFileControl" type="file" /> control, or React DropZone. To get the file, you're doing something like var myFile = document.getElementById("myFileControl")[0]; or myFile = this.state.files[0];.

From there, I'd get the base64 string using code here: Convert input=file to byte array (use function UploadFile2).

Then I'd get that string, the file name (myFile.name) and type (myFile.type) into a JSON object:

var myJSONObj = {
    file: base64string,
    name: myFile.name,
    type: myFile.type,
}

and post the file to an MVC server backend using XMLHttpRequest, specifying a Content-Type of application/json: xhr.send(JSON.stringify(myJSONObj);. You have to build a ViewModel to bind it with:

public class MyModel
{
    public string file { get; set; }
    public string title { get; set; }
    public string type { get; set; }
}

and specify [FromBody]MyModel myModelObj as the passed in parameter:

[System.Web.Http.HttpPost]  // required to spell it out like this if using ApiController, or it will default to System.Mvc.Http.HttpPost
public virtual ActionResult Post([FromBody]MyModel myModelObj)

Then you can add this into that function and save it using Entity Framework:

MY_ATTACHMENT_TABLE_MODEL tblAtchm = new MY_ATTACHMENT_TABLE_MODEL();
tblAtchm.Name = myModelObj.name;
tblAtchm.Type = myModelObj.type;
tblAtchm.File = System.Convert.FromBase64String(myModelObj.file);
EntityFrameworkContextName ef = new EntityFrameworkContextName();
ef.MY_ATTACHMENT_TABLE_MODEL.Add(tblAtchm);
ef.SaveChanges();

tblAtchm.File = System.Convert.FromBase64String(myModelObj.file); being the operative line.

You would need a model to represent the database table:

public class MY_ATTACHMENT_TABLE_MODEL 
{
    [Key]
    public byte[] File { get; set; }  // notice this change
    public string Name { get; set; }
    public string Type { get; set; }
}

This will save the data into a varbinary(max) field as a byte[]. Name and Type were nvarchar(250) and nvarchar(10), respectively. You could include size by adding it to your table as an int column & MY_ATTACHMENT_TABLE_MODEL as public int Size { get; set;}, and add in the line tblAtchm.Size = System.Convert.FromBase64String(myModelObj.file).Length; above.

Oracle

Short answer: Convert it to a byte[], assign it to an OracleParameter, add it to your OracleCommand, and update your table's BLOB field using a reference to the parameter's ParameterName value: :BlobParameter

Long answer: When I did this for Oracle, I was using an OpenFileDialog and I retrieved and sent the bytes/file information this way:

byte[] array;
OracleParameter param = new OracleParameter();
Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
dlg.Filter = "Image Files (*.jpg, *.jpeg, *.jpe)|*.jpg;*.jpeg;*.jpe|Document Files (*.doc, *.docx, *.pdf)|*.doc;*.docx;*.pdf"
if (dlg.ShowDialog().Value == true)
{
    string fileName = dlg.FileName;
    using (FileStream fs = File.OpenRead(fileName)
    {
        array = new byte[fs.Length];
        using (BinaryReader binReader = new BinaryReader(fs))
        {
            array = binReader.ReadBytes((int)fs.Length);
        }

        // Create an OracleParameter to transmit the Blob
        param.OracleDbType = OracleDbType.Blob;
        param.ParameterName = "BlobParameter";
        param.Value = array;  // <-- file bytes are here
    }
    fileName = fileName.Split('\\')[fileName.Split('\\').Length-1]; // gets last segment of the whole path to just get the name

    string fileType = fileName.Split('.')[1];
    if (fileType == "doc" || fileType == "docx" || fileType == "pdf")
        fileType = "application\\" + fileType;
    else
        fileType = "image\\" + fileType;

    // SQL string containing reference to BlobParameter named above
    string sql = String.Format("INSERT INTO YOUR_TABLE (FILE_NAME, FILE_TYPE, FILE_SIZE, FILE_CONTENTS, LAST_MODIFIED) VALUES ('{0}','{1}',{2},:BlobParamerter, SYSDATE)", fileName, fileType, array.Length);

    // Do Oracle Update
    RunCommand(sql, param);
}

And inside the Oracle update, done with ADO:

public void RunCommand(string sql, OracleParameter param)
{
    OracleConnection oraConn = null;
    OracleCommand oraCmd = null;
    try
    {
        string connString = GetConnString();
        oraConn = OracleConnection(connString);
        using (oraConn)
        {
            if (OraConnection.State == ConnectionState.Open)
                OraConnection.Close();

            OraConnection.Open();

            oraCmd = new OracleCommand(strSQL, oraConnection);

            // Add your OracleParameter
            if (param != null)
                OraCommand.Parameters.Add(param);

            // Execute the command
            OraCommand.ExecuteNonQuery();
        }
    }
    catch (OracleException err)
    {
       // handle exception 
    }
    finally
    {
       OraConnction.Close();
    }
}

private string GetConnString()
{
    string host = System.Configuration.ConfigurationManager.AppSettings["host"].ToString();
    string port = System.Configuration.ConfigurationManager.AppSettings["port"].ToString();
    string serviceName = System.Configuration.ConfigurationManager.AppSettings["svcName"].ToString();
    string schemaName = System.Configuration.ConfigurationManager.AppSettings["schemaName"].ToString();
    string pword = System.Configuration.ConfigurationManager.AppSettings["pword"].ToString(); // hopefully encrypted

    if (String.IsNullOrEmpty(host) || String.IsNullOrEmpty(port) || String.IsNullOrEmpty(serviceName) || String.IsNullOrEmpty(schemaName) || String.IsNullOrEmpty(pword))
    {
        return "Missing Param";
    }
    else
    {
        pword = decodePassword(pword);  // decrypt here
        return String.Format(
           "Data Source=(DESCRIPTION =(ADDRESS = ( PROTOCOL = TCP)(HOST = {2})(PORT = {3}))(CONNECT_DATA =(SID = {4})));User Id={0};Password={1};",
           user,
           pword,
           host,
           port,
           serviceName
           );
    }
}

And the datatype for the FILE_CONTENTS column was BLOB, the FILE_SIZE was NUMBER(10,0), LAST_MODIFIED was DATE, and the rest were NVARCHAR2(250).

How do I reset the scale/zoom of a web app on an orientation change on the iPhone?

Found a very easily implemented fix. Set the focus to a text element that has a font size of 50px on completion of the form. It does not seem to work if the text element is hidden but hiding this element is easily done by setting the elements color properties to have no opacity.

Pandas index column title or name

If you do not want to create a new row but simply put it in the empty cell then use:

df.columns.name = 'foo'

Otherwise use:

df.index.name = 'foo'

How can I delete a service in Windows?

Use services.msc or (Start > Control Panel > Administrative Tools > Services) to find the service in question. Double-click to see the service name and the path to the executable.

Check the exe version information for a clue as to the owner of the service, and use Add/Remove programs to do a clean uninstall if possible.

Failing that, from the command prompt:

sc stop servicexyz
sc delete servicexyz

No restart should be required.

How to open the second form?

//To open the form

Form2 form2 = new Form2();

form2.Show();
// And to close
form2.Close();

Hope this helps

"The certificate chain was issued by an authority that is not trusted" when connecting DB in VM Role from Azure website

The same can be achieved from ssms client itself. Just open the ssms, insert the server name and then from options under heading connection properties make sure Trust server certificate is checked.

Error: org.testng.TestNGException: Cannot find class in classpath: EmpClass

If you use IntelliJ IDEA, try the following:

  1. From 'File', select "Invalidate Caches/ Restart" option.
  2. Confirm this action by clicking the "Invalidate and Restart" button.
  3. Then the IDEA will be restarted.
  4. You will then find a fresh copy of your project.
  5. You then need to import/ change project format to the Maven project. IDEA will show you options at the bottom right corner.
  6. After this, you should be able to run your project.

Read XML file using javascript

The code below will convert any XMLObject or string to a native JavaScript object. Then you can walk on the object to extract any value you want.

/**
 * Tries to convert a given XML data to a native JavaScript object by traversing the DOM tree.
 * If a string is given, it first tries to create an XMLDomElement from the given string.
 * 
 * @param {XMLDomElement|String} source The XML string or the XMLDomElement prefreably which containts the necessary data for the object.
 * @param {Boolean} [includeRoot] Whether the "required" main container node should be a part of the resultant object or not.
 * @return {Object} The native JavaScript object which is contructed from the given XML data or false if any error occured.
 */
Object.fromXML = function( source, includeRoot ) {
    if( typeof source == 'string' )
    {
        try
        {
            if ( window.DOMParser )
                source = ( new DOMParser() ).parseFromString( source, "application/xml" );
            else if( window.ActiveXObject )
            {
                var xmlObject = new ActiveXObject( "Microsoft.XMLDOM" );
                xmlObject.async = false;
                xmlObject.loadXML( source );
                source = xmlObject;
                xmlObject = undefined;
            }
            else
                throw new Error( "Cannot find an XML parser!" );
        }
        catch( error )
        {
            return false;
        }
    }

    var result = {};

    if( source.nodeType == 9 )
        source = source.firstChild;
    if( !includeRoot )
        source = source.firstChild;

    while( source ) {
        if( source.childNodes.length ) {
            if( source.tagName in result ) {
                if( result[source.tagName].constructor != Array ) 
                    result[source.tagName] = [result[source.tagName]];
                result[source.tagName].push( Object.fromXML( source ) );
            }
            else 
                result[source.tagName] = Object.fromXML( source );
        } else if( source.tagName )
            result[source.tagName] = source.nodeValue;
        else if( !source.nextSibling ) {
            if( source.nodeValue.clean() != "" ) {
                result = source.nodeValue.clean();
            }
        }
        source = source.nextSibling;
    }
    return result;
};

String.prototype.clean = function() {
    var self = this;
    return this.replace(/(\r\n|\n|\r)/gm, "").replace(/^\s+|\s+$/g, "");
}

Xcode 6.1 Missing required architecture X86_64 in file

If you are having this problem in react-native projects with one of the external library. You should remove the project and use react-native link <package-name> again. That should solve the problem.

How do I check if a string is valid JSON in Python?

You can try to do json.loads(), which will throw a ValueError if the string you pass can't be decoded as JSON.

In general, the "Pythonic" philosophy for this kind of situation is called EAFP, for Easier to Ask for Forgiveness than Permission.

mailto link multiple body lines

You can use URL encoding to encode the newline as %0A.

mailto:[email protected]?subject=test&body=type%20your%0Amessage%20here

While the above appears to work in many cases, user olibre points out that the RFC governing the mailto URI scheme specifies that %0D%0A (carriage return + line feed) should be used instead of %0A (line feed). See also: Newline Representations.

The smallest difference between 2 Angles

There is no need to compute trigonometric functions. The simple code in C language is:

#include <math.h>
#define PIV2 M_PI+M_PI
#define C360 360.0000000000000000000
double difangrad(double x, double y)
{
double arg;

arg = fmod(y-x, PIV2);
if (arg < 0 )  arg  = arg + PIV2;
if (arg > M_PI) arg  = arg - PIV2;

return (-arg);
}
double difangdeg(double x, double y)
{
double arg;
arg = fmod(y-x, C360);
if (arg < 0 )  arg  = arg + C360;
if (arg > 180) arg  = arg - C360;
return (-arg);
}

let dif = a - b , in radians

dif = difangrad(a,b);

let dif = a - b , in degrees

dif = difangdeg(a,b);

difangdeg(180.000000 , -180.000000) = 0.000000
difangdeg(-180.000000 , 180.000000) = -0.000000
difangdeg(359.000000 , 1.000000) = -2.000000
difangdeg(1.000000 , 359.000000) = 2.000000

No sin, no cos, no tan,.... only geometry!!!!

How to open a website when a Button is clicked in Android application?

You can wrap the buttons in anchors that href to the appropriate website.

<a href="http://www.stackoverflow.com">
  <input type="button" value="Button" />
</a>
<a href="http://www.stackoverflow.com">
  <input type="button" value="Button" />
</a>
<a href="http://www.stackoverflow.com">
  <input type="button" value="Button" />
</a>

When the user clicks the button (input) they are directed to the destination specified in the href property of the anchor.

Edit: Oops, I didn't read "Eclipse" in the question title. My mistake.

Application.WorksheetFunction.Match method

You are getting this error because the value cannot be found in the range. String or integer doesn't matter. Best thing to do in my experience is to do a check first to see if the value exists.

I used CountIf below, but there is lots of different ways to check existence of a value in a range.

Public Sub test()

Dim rng As Range
Dim aNumber As Long

aNumber = 666

Set rng = Sheet5.Range("B16:B615")

    If Application.WorksheetFunction.CountIf(rng, aNumber) > 0 Then

        rowNum = Application.WorksheetFunction.Match(aNumber, rng, 0)

    Else
        MsgBox aNumber & " does not exist in range " & rng.Address
    End If

End Sub

ALTERNATIVE WAY

Public Sub test()
    Dim rng As Range
    Dim aNumber As Variant
    Dim rowNum As Long

    aNumber = "2gg"

    Set rng = Sheet5.Range("B1:B20")

    If Not IsError(Application.Match(aNumber, rng, 0)) Then
        rowNum = Application.Match(aNumber, rng, 0)
        MsgBox rowNum
    Else
        MsgBox "error"
    End If
End Sub

OR

Public Sub test()
    Dim rng As Range
    Dim aNumber As Variant
    Dim rowNum As Variant

    aNumber = "2gg"

    Set rng = Sheet5.Range("B1:B20")

    rowNum = Application.Match(aNumber, rng, 0)

    If Not IsError(rowNum) Then
        MsgBox rowNum
    Else
        MsgBox "error"
    End If
End Sub

Nuget connection attempt failed "Unable to load the service index for source"

I was using an older version of Nuget on VS2010, where it defaults to TLS 1.0 here it can be fixed by changing the default TLS version used by .Net framework which is configured in Registry keys

reg add HKLM\SOFTWARE\Microsoft\.NETFramework\v4.0.30319 /v SystemDefaultTlsVersions /t REG_DWORD /d 1 /f /reg:64

reg add HKLM\SOFTWARE\Microsoft\.NETFramework\v4.0.30319 /v SystemDefaultTlsVersions /t REG_DWORD /d 1 /f /reg:32

FYI

NuGet.org will permanently remove support for TLS 1.0 and 1.1 on June 15th. Please ensure that your systems use TLS 1.2.

You can refer to this link for info on TLS 1.2 support

Ruby combining an array into one string

Use the Array#join method (the argument to join is what to insert between the strings - in this case a space):

@arr.join(" ")

Set disable attribute based on a condition for Html.TextBoxFor

Yet another solution would be to create a Dictionary<string, object> before calling TextBoxFor and pass that dictionary. In the dictionary, add "disabled" key only if the textbox is to be diabled. Not the neatest solution but simple and straightforward.

How do I display local image in markdown?

The best solution is to provide a path relative to the folder where the md document is located.

Probably a browser is in trouble when it tries to resolve the absolute path of a local file. That can be solved by accessing the file trough a webserver, but even in that situation, the image path has to be right.

Having a folder at the same level of the document, containing all the images, is the cleanest and safest solution. It will load on GitHub, local, local webserver.

images_folder/img.jpg  < works


/images_folder/img.jpg  < this will work on webserver's only (please read the note!)

Using the absolute path, the image will be accessible only with a url like this: http://hostname.doesntmatter/image_folder/img.jpg

Apache HttpClient Interim Error: NoHttpResponseException

Solution: change the ReuseStrategy to never

Since this problem is very complex and there are so many different factors which can fail I was happy to find this solution in another post: How to solve org.apache.http.NoHttpResponseException

Never reuse connections: configure in org.apache.http.impl.client.AbstractHttpClient:

httpClient.setReuseStrategy(new NoConnectionReuseStrategy());

The same can be configured on a org.apache.http.impl.client.HttpClientBuilder builder:

builder.setConnectionReuseStrategy(new NoConnectionReuseStrategy());

Insert data to MySql DB and display if insertion is success or failure

According to the book PHP and MySQL for Dynamic Web Sites (4th edition)

Example:

$r = mysqli_query($dbc, $q);

For simple queries like INSERT, UPDATE, DELETE, etc. (which do not return records), the $r variable—short for result—will be either TRUE or FALSE, depending upon whether the query executed successfully.

Keep in mind that “executed successfully” means that it ran without error; it doesn’t mean that the query’s execution necessarily had the desired result; you’ll need to test for that.

Then how to test?

While the mysqli_num_rows() function will return the number of rows generated by a SELECT query, mysqli_affected_rows() returns the number of rows affected by an INSERT, UPDATE, or DELETE query. It’s used like so:

$num = mysqli_affected_rows($dbc);

Unlike mysqli_num_rows(), the one argument the function takes is the database connection ($dbc), not the results of the previous query ($r).

Can't connect to local MySQL server through socket '/var/mysql/mysql.sock' (38)

I used 127.0.0.1 for -h instead localhost and everything was OK. In other case had what had - error that above.

change the date format in laravel view page

I had a similar problem, I wanted to change the format, but I also wanted the flexibility of being able to change the format in the blade template engine too.

I, therefore, set my model up as the following:

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

\Carbon\Carbon::setToStringFormat('d-m-Y');

class User extends Model
{
    protected $dates = [
        'from_date',
    ];
}

The setToStringFormat will set all the dates to use this format for this model.
The advantage of this for me is that I could have the format that I wanted without the mutator, because with the mutator, the attribute is returned as a string meaning that in the blade template I would have to write something like this if I wanted to change the format in the template:

{{ date('Y', strtotime($user->from_date)) }}

Which isn't very clean.

Instead, the attribute is still returned as a Carbon instance, however it is first returned in the desired format.
That means that in the template I could write the following, cleaner, code:

{{ $user->from_date->format('Y') }}

In addition to being able to reformat the Carbon instance, I can also call various Carbon methods on the attribute in the template.

There is probably an oversight to this approach; I'm going to wager it is not a good idea to specify the string format at the top of the model in case it affects other scripts. From what I have seen so far, that has not happened. It has only changed the default Carbon for that model only.

In this instance, it might be a good set the Carbon format back to what it was originally at the bottom of the model script. This is a bodged idea, but it would work for each model to have its own format.
Contrary, if you are having the same format for each model then in your AppServiceProvider instead. That would just keep the code neater and easier to maintain.

sql query to return differences between two tables

To get all the differences between two tables, you can use like me this SQL request :

SELECT 'TABLE1-ONLY' AS SRC, T1.*
FROM (
      SELECT * FROM Table1
      EXCEPT
      SELECT * FROM Table2
      ) AS T1
UNION ALL
SELECT 'TABLE2-ONLY' AS SRC, T2.*
FROM (
      SELECT * FROM Table2
      EXCEPT
      SELECT * FROM Table1
      ) AS T2
;

How to query a CLOB column in Oracle

When getting the substring of a CLOB column and using a query tool that has size/buffer restrictions sometimes you would need to set the BUFFER to a larger size. For example while using SQL Plus use the SET BUFFER 10000 to set it to 10000 as the default is 4000.

Running the DBMS_LOB.substr command you can also specify the amount of characters you want to return and the offset from which. So using DBMS_LOB.substr(column, 3000) might restrict it to a small enough amount for the buffer.

See oracle documentation for more info on the substr command


    DBMS_LOB.SUBSTR (
       lob_loc     IN    CLOB   CHARACTER SET ANY_CS,
       amount      IN    INTEGER := 32767,
       offset      IN    INTEGER := 1)
      RETURN VARCHAR2 CHARACTER SET lob_loc%CHARSET;

What is the most efficient way to check if a value exists in a NumPy array?

Adding to @HYRY's answer in1d seems to be fastest for numpy. This is using numpy 1.8 and python 2.7.6.

In this test in1d was fastest, however 10 in a look cleaner:

a = arange(0,99999,3)
%timeit 10 in a
%timeit in1d(a, 10)

10000 loops, best of 3: 150 µs per loop
10000 loops, best of 3: 61.9 µs per loop

Constructing a set is slower than calling in1d, but checking if the value exists is a bit faster:

s = set(range(0, 99999, 3))
%timeit 10 in s

10000000 loops, best of 3: 47 ns per loop

HTTP Basic Authentication - what's the expected web browser experience?

WWW-Authenticate header

You may also get this if the server is sending a 401 response code but not setting the WWW-Authenticate header correctly - I should know, I've just fixed that in out own code because VB apps weren't popping up the authentication prompt.

Throwing multiple exceptions in a method of an interface in java

You need to specify it on the methods that can throw the exceptions. You just seperate them with a ',' if it can throw more than 1 type of exception. e.g.

public interface MyInterface {
  public MyObject find(int x) throws MyExceptionA,MyExceptionB;
}

Problems when trying to load a package in R due to rJava

An alternative package that you can use is readxl. This package don't require external dependencies.

Setting the target version of Java in ant javac

Both source and target should be specified. I recommend providing ant defaults, that way you do not need to specify source/target attribute for every javac task:

<property name="ant.build.javac.source" value="1.5"/>
<property name="ant.build.javac.target" value="1.5"/>

See Java cross-compiling notes for more information.

How do I use the JAVA_OPTS environment variable?

Actually, you can, even though accepted answer saying that you can't.

There is a _JAVA_OPTIONS environment variable, more about it here

How to fix '.' is not an internal or external command error

I got exactly the same error in Windows 8 while trying to export decision tree digraph using tree.export_graphviz! Then I installed GraphViz from this link. And then I followed the below steps which resolved my issue:

  • Right click on My PC >> click on "Change Settings" under "Computer name, domain, and workgroup settings"
  • It will open the System Properties window; Goto 'Advanced' tab >> click on 'Environment Variables' >> Under "System Variables" >> select 'Path' and click on 'Edit' >> In 'Variable Value' field, put a semicolon (;) at the end of existing value and then include the path of its installation folder (e.g. ;C:\Program Files (x86)\Graphviz2.38\bin) >> Click on 'Ok' >> 'Ok' >> 'Ok'
  • Restart your PC as environment variables are changed

Error creating bean with name 'entityManagerFactory

This sounds like a ClassLoader conflict. I'd bet you have the javax.persistence api 1.x on the classpath somewhere, whereas Spring is trying to access ValidationMode, which was only introduced in JPA 2.0.

Since you use Maven, do mvn dependency:tree, find the artifact:

<dependency>
    <groupId>javax.persistence</groupId>
    <artifactId>persistence-api</artifactId>
    <version>1.0</version>
</dependency>

And remove it from your setup. (See Excluding Dependencies)

AFAIK there is no such general distribution for JPA 2, but you can use this Hibernate-specific version:

<dependency>
    <groupId>org.hibernate.javax.persistence</groupId>
    <artifactId>hibernate-jpa-2.0-api</artifactId>
    <version>1.0.1.Final</version>
</dependency>

OK, since that doesn't work, you still seem to have some JPA-1 version in there somewhere. In a test method, add this code:

System.out.println(EntityManager.class.getProtectionDomain()
                                      .getCodeSource()
                                      .getLocation());

See where that points you and get rid of that artifact.


Ahh, now I finally see the problem. Get rid of this:

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jpa</artifactId>
    <version>2.0.8</version>
</dependency>

and replace it with

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-orm</artifactId>
    <version>3.2.5.RELEASE</version>
</dependency>

On a different note, you should set all test libraries (spring-test, easymock etc.) to

<scope>test</scope>

Oracle SQL - DATE greater than statement

As your query string is a literal, and assuming your dates are properly stored as DATE you should use date literals:

SELECT * FROM OrderArchive
WHERE OrderDate <= DATE '2015-12-31'

If you want to use TO_DATE (because, for example, your query value is not a literal), I suggest you to explicitly set the NLS_DATE_LANGUAGE parameter as you are using US abbreviated month names. That way, it won't break on some localized Oracle Installation:

SELECT * FROM OrderArchive
WHERE OrderDate <= to_date('31 Dec 2014', 'DD MON YYYY',
                           'NLS_DATE_LANGUAGE = American');

SessionTimeout: web.xml vs session.maxInactiveInterval()

Now, i'm being told that this will terminate the session (or is it all sessions?) in the 15th minute of use, regardless their activity.

This is wrong. It will just kill the session when the associated client (webbrowser) has not accessed the website for more than 15 minutes. The activity certainly counts, exactly as you initially expected, seeing your attempt to solve this.

The HttpSession#setMaxInactiveInterval() doesn't change much here by the way. It does exactly the same as <session-timeout> in web.xml, with the only difference that you can change/set it programmatically during runtime. The change by the way only affects the current session instance, not globally (else it would have been a static method).


To play around and experience this yourself, try to set <session-timeout> to 1 minute and create a HttpSessionListener like follows:

@WebListener
public class HttpSessionChecker implements HttpSessionListener {

    public void sessionCreated(HttpSessionEvent event) {
        System.out.printf("Session ID %s created at %s%n", event.getSession().getId(), new Date());
    }

    public void sessionDestroyed(HttpSessionEvent event) {
        System.out.printf("Session ID %s destroyed at %s%n", event.getSession().getId(), new Date());
    }

}

(if you're not on Servlet 3.0 yet and thus can't use @WebListener, then register in web.xml as follows):

<listener>
    <listener-class>com.example.HttpSessionChecker</listener-class>
</listener>

Note that the servletcontainer won't immediately destroy sessions after exactly the timeout value. It's a background job which runs at certain intervals (e.g. 5~15 minutes depending on load and the servletcontainer make/type). So don't be surprised when you don't see destroyed line in the console immediately after exactly one minute of inactivity. However, when you fire a HTTP request on a timed-out-but-not-destroyed-yet session, it will be destroyed immediately.

See also:

Does not contain a definition for and no extension method accepting a first argument of type could be found

placeBets(betList, stakeAmt) is an instance method not a static method. You need to create an instance of CBetfairAPI first:

MyBetfair api = new MyBetfair();
ArrayList bets = api.placeBets(betList, stakeAmt);

VBA - how to conditionally skip a for loop iteration

Continue For isn't valid in VBA or VB6.

From this MSDN page it looks to have been introduced into VB.Net in VS 2005./Net 2.

As the others have said there's not really an option other than to use Goto or an Else.

MySQL JOIN ON vs USING?

Wikipedia has the following information about USING:

The USING construct is more than mere syntactic sugar, however, since the result set differs from the result set of the version with the explicit predicate. Specifically, any columns mentioned in the USING list will appear only once, with an unqualified name, rather than once for each table in the join. In the case above, there will be a single DepartmentID column and no employee.DepartmentID or department.DepartmentID.

Tables that it was talking about:

enter image description here

The Postgres documentation also defines them pretty well:

The ON clause is the most general kind of join condition: it takes a Boolean value expression of the same kind as is used in a WHERE clause. A pair of rows from T1 and T2 match if the ON expression evaluates to true.

The USING clause is a shorthand that allows you to take advantage of the specific situation where both sides of the join use the same name for the joining column(s). It takes a comma-separated list of the shared column names and forms a join condition that includes an equality comparison for each one. For example, joining T1 and T2 with USING (a, b) produces the join condition ON T1.a = T2.a AND T1.b = T2.b.

Furthermore, the output of JOIN USING suppresses redundant columns: there is no need to print both of the matched columns, since they must have equal values. While JOIN ON produces all columns from T1 followed by all columns from T2, JOIN USING produces one output column for each of the listed column pairs (in the listed order), followed by any remaining columns from T1, followed by any remaining columns from T2.

How to use Jquery how to change the aria-expanded="false" part of a dom element (Bootstrap)?

You can use .attr() as a part of however you plan to toggle it:

$("button").attr("aria-expanded","true");

What is the difference between a Docker image and a container?

A Docker image packs up the application and environment required by the application to run, and a container is a running instance of the image.

Images are the packing part of Docker, analogous to "source code" or a "program". Containers are the execution part of Docker, analogous to a "process".

In the question, only the "program" part is referred to and that's the image. The "running" part of Docker is the container. When a container is run and changes are made, it's as if the process makes a change in its own source code and saves it as the new image.

How do I revert an SVN commit?

I tried the above, (svn merge) and you're right, it does jack. However

svn update -r <revision> <target> [-R]

seems to work, but isn't permanent (my svn is simply showing an old revision). So I had to

mv <target> <target backup>
svn update <target>
mv <target backup> <target>
svn commit -m "Reverted commit on <target>" <target>

In my particular case my target is interfaces/AngelInterface.php. I made changes to the file, committed them, updated the build computer ran the phpdoc compiler and found my changes were a waste of time. svn log interfaces/AngelInterface.php shows my change as r22060 and the previous commit on that file was r22059. So I can svn update -r 22059 interfaces/AngelInterface.php and I end up with code as it was in -r22059 again. Then :-

mv interfaces/AngelInterface.php interfaces/AngelInterface.php~
svn update interfaces/AngelInterface.php
mv interfaces/AngelInterface.php~ interfaces/AngelInterface.php
svn commit -m "reverted -r22060" interfaces/AngelInterface.php

Alternatively I could do the same thing on a directory, by specifying . -R in place of interfaces/AngelInterface.php in all the above.

How to write text on a image in windows using python opencv2

This code uses cv2.putText to overlay text on an image. You need NumPy and OpenCV installed.

import numpy as np
import cv2

# Create a black image
img = np.zeros((512,512,3), np.uint8)

# Write some Text

font                   = cv2.FONT_HERSHEY_SIMPLEX
bottomLeftCornerOfText = (10,500)
fontScale              = 1
fontColor              = (255,255,255)
lineType               = 2

cv2.putText(img,'Hello World!', 
    bottomLeftCornerOfText, 
    font, 
    fontScale,
    fontColor,
    lineType)

#Display the image
cv2.imshow("img",img)

#Save image
cv2.imwrite("out.jpg", img)

cv2.waitKey(0)

Apache POI error loading XSSFWorkbook class

If you have downloaded pio-3.17 On eclipse: right click on the project folder -> build path -> configure build path -> libraries -> add external jars -> add all the commons jar file from the "lib". It's worked for me.

How to find the length of an array in shell?

in tcsh or csh:

~> set a = ( 1 2 3 4 5 )
~> echo $#a
5

Can we cast a generic object to a custom object type in javascript?

No.

But if you're looking to treat your person1 object as if it were a Person, you can call methods on Person's prototype on person1 with call:

Person.prototype.getFullNamePublic = function(){
    return this.lastName + ' ' + this.firstName;
}
Person.prototype.getFullNamePublic.call(person1);

Though this obviously won't work for privileged methods created inside of the Person constructor—like your getFullName method.

IIS: Idle Timeout vs Recycle

Idle Timeout is if no action has been asked from your web app, it the process will drop and release everything from memory

Recycle is a forced action on the application where your processed is closed and started again, for memory leaking purposes and system health

The negative impact of both is usually the use of your Session and Application state is lost if you mess with Recycle to a faster time.(logged in users etc will be logged out, if they where about to "check out" all would have been lost" that's why recycle is at such a large time out value, idle timeout doesn't matter because nobody is logged in anyway and figure 20 minutes an no action they are not still "shopping"

The positive would be get rid of the idle time out as your website will respond faster on its "first" response if its not a highly active site where a user would have to wait for it to load if you have 1 user every 20 minutes lets say. So a website that get his less then 1 time in 20 minutes actually you would want to increase this value as the website has to load up again from scratch for each user. but if you set this to 0 over a long time, any memory leaks in code could over a certain amount of time, entirely take over the server.

awk without printing newline

The ORS (output record separator) variable in AWK defaults to "\n" and is printed after every line. You can change it to " " in the BEGIN section if you want everything printed consecutively.

Fast ceiling of an integer division in C / C++

simplified generic form,

int div_up(int n, int d) {
    return n / d + (((n < 0) ^ (d > 0)) && (n % d));
} //i.e. +1 iff (not exact int && positive result)

For a more generic answer, C++ functions for integer division with well defined rounding strategy

Importing class from another file

Your problem is basically that you never specified the right path to the file.

Try instead, from your main script:

from folder.file import Klasa

Or, with from folder import file:

from folder import file
k = file.Klasa()

Or again:

import folder.file as myModule
k = myModule.Klasa()

PHP and MySQL Select a Single Value

When you use mysql_fetch_object, you get an object (of class stdClass) with all fields for the row inside of it.

Use mysql_fetch_field instead of mysql_fetch_object, that will give you the first field of the result set (id in your case). The docs are here

How to handle calendar TimeZones using Java?

public static Calendar convertToGmt(Calendar cal) {

    Date date = cal.getTime();
    TimeZone tz = cal.getTimeZone();

    log.debug("input calendar has date [" + date + "]");

    //Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT 
    long msFromEpochGmt = date.getTime();

    //gives you the current offset in ms from GMT at the current date
    int offsetFromUTC = tz.getOffset(msFromEpochGmt);
    log.debug("offset is " + offsetFromUTC);

    //create a new calendar in GMT timezone, set to this date and add the offset
    Calendar gmtCal = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
    gmtCal.setTime(date);
    gmtCal.add(Calendar.MILLISECOND, offsetFromUTC);

    log.debug("Created GMT cal with date [" + gmtCal.getTime() + "]");

    return gmtCal;
}

Here's the output if I pass the current time ("12:09:05 EDT" from Calendar.getInstance()) in:

DEBUG - input calendar has date [Thu Oct 23 12:09:05 EDT 2008]
DEBUG - offset is -14400000
DEBUG - Created GMT cal with date [Thu Oct 23 08:09:05 EDT 2008]

12:09:05 GMT is 8:09:05 EDT.

The confusing part here is that Calendar.getTime() returns you a Date in your current timezone, and also that there is no method to modify the timezone of a calendar and have the underlying date rolled also. Depending on what type of parameter your web service takes, your may just want to have the WS deal in terms of milliseconds from epoch.

How to convert hex string to Java string?

First of all read in the data, then convert it to byte array:

 byte b = Byte.parseByte(str, 16); 

and then use String constructor:

new String(byte[] bytes) 

or if the charset is not system default then:

new String(byte[] bytes, String charsetName) 

Getting each individual digit from a whole integer

//this can be easily understandable for beginners     
int score=12344534;
int div;
for (div = 1; div <= score; div *= 10)
{

}
/*for (div = 1; div <= score; div *= 10); for loop with semicolon or empty body is same*/
while(score>0)
{
    div /= 10;
    printf("%d\n`enter code here`", score / div);
    score %= div;
}

Why does NULL = NULL evaluate to false in SQL server

null is unknown in sql so we cant expect two unknowns to be same.

However you can get that behavior by setting ANSI_NULLS to Off(its On by Default) You will be able to use = operator for nulls

SET ANSI_NULLS off
if null=null
print 1
else 
print 2
set ansi_nulls on
if null=null
print 1
else 
print 2

How to use "like" and "not like" in SQL MSAccess for the same field?

If you're doing it in VBA (and not in a query) then: where field like "AA" and field not like "BB" then would not work.

You'd have to use: where field like "AA" and field like "BB" = false then

How to set $_GET variable

You could use the following code to redirect your client to a script with the _GET variables attached.

header("Location: examplepage.php?var1=value&var2=value");
die();

This will cause the script to redirect, make sure the die(); is kept in there, or they may not redirect.

List of tuples to dictionary

The dict constructor accepts input exactly as you have it (key/value tuples).

>>> l = [('a',1),('b',2)]
>>> d = dict(l)
>>> d
{'a': 1, 'b': 2}

From the documentation:

For example, these all return a dictionary equal to {"one": 1, "two": 2}:

dict(one=1, two=2)
dict({'one': 1, 'two': 2})
dict(zip(('one', 'two'), (1, 2)))
dict([['two', 2], ['one', 1]])

How do I revert all local changes in Git managed project to previous state?

Re-clone

GIT=$(git rev-parse --show-toplevel)
cd $GIT/..
rm -rf $GIT
git clone ...
  • ? Deletes local, non-pushed commits
  • ? Reverts changes you made to tracked files
  • ? Restores tracked files you deleted
  • ? Deletes files/dirs listed in .gitignore (like build files)
  • ? Deletes files/dirs that are not tracked and not in .gitignore
  • You won't forget this approach
  • Wastes bandwidth

Following are other commands I forget daily.

Clean and reset

git clean --force -d -x
git reset --hard
  • ? Deletes local, non-pushed commits
  • ? Reverts changes you made to tracked files
  • ? Restores tracked files you deleted
  • ? Deletes files/dirs listed in .gitignore (like build files)
  • ? Deletes files/dirs that are not tracked and not in .gitignore

Clean

git clean --force -d -x
  • ? Deletes local, non-pushed commits
  • ? Reverts changes you made to tracked files
  • ? Restores tracked files you deleted
  • ? Deletes files/dirs listed in .gitignore (like build files)
  • ? Deletes files/dirs that are not tracked and not in .gitignore

Reset

git reset --hard
  • ? Deletes local, non-pushed commits
  • ? Reverts changes you made to tracked files
  • ? Restores tracked files you deleted
  • ? Deletes files/dirs listed in .gitignore (like build files)
  • ? Deletes files/dirs that are not tracked and not in .gitignore

Notes

Test case for confirming all the above (use bash or sh):

mkdir project
cd project
git init
echo '*.built' > .gitignore
echo 'CODE' > a.sourceCode
mkdir b
echo 'CODE' > b/b.sourceCode
cp -r b c
git add .
git commit -m 'Initial checkin'
echo 'NEW FEATURE' >> a.sourceCode
cp a.sourceCode a.built
rm -rf c
echo 'CODE' > 'd.sourceCode'

See also

  • git revert to make new commits that undo prior commits
  • git checkout to go back in time to prior commits (may require running above commands first)
  • git stash same as git reset above, but you can undo it

select rows in sql with latest date for each ID repeated multiple times

One way is:

select table.* 
from table
join 
(
    select ID, max(Date) as max_dt 
    from table
    group by ID
) t
on table.ID= t.ID and table.Date = t.max_dt 

Note that if you have multiple equally higher dates for same ID, then you will get all those rows in result

strcpy() error in Visual studio 2012

If you are getting an error saying something about deprecated functions, try doing #define _CRT_SECURE_NO_WARNINGS or #define _CRT_SECURE_NO_DEPRECATE. These should fix it. You can also use Microsoft's "secure" functions, if you want.

Display a angular variable in my html page

In your template, you have access to all the variables that are members of the current $scope. So, tobedone should be $scope.tobedone, and then you can display it with {{tobedone}}, or [[tobedone]] in your case.

Loop through all nested dictionary values?

There are potential problems if you write your own recursive implementation or the iterative equivalent with stack. See this example:

    dic = {}
    dic["key1"] = {}
    dic["key1"]["key1.1"] = "value1"
    dic["key2"]  = {}
    dic["key2"]["key2.1"] = "value2"
    dic["key2"]["key2.2"] = dic["key1"]
    dic["key2"]["key2.3"] = dic

In the normal sense, nested dictionary will be a n-nary tree like data structure. But the definition doesn't exclude the possibility of a cross edge or even a back edge (thus no longer a tree). For instance, here key2.2 holds to the dictionary from key1, key2.3 points to the entire dictionary(back edge/cycle). When there is a back edge(cycle), the stack/recursion will run infinitely.

                          root<-------back edge
                        /      \           |
                     _key1   __key2__      |
                    /       /   \    \     |
               |->key1.1 key2.1 key2.2 key2.3
               |   /       |      |
               | value1  value2   |
               |                  | 
              cross edge----------|

If you print this dictionary with this implementation from Scharron

    def myprint(d):
      for k, v in d.items():
        if isinstance(v, dict):
          myprint(v)
        else:
          print "{0} : {1}".format(k, v)

You would see this error:

    RuntimeError: maximum recursion depth exceeded while calling a Python object

The same goes with the implementation from senderle.

Similarly, you get an infinite loop with this implementation from Fred Foo:

    def myprint(d):
        stack = list(d.items())
        while stack:
            k, v = stack.pop()
            if isinstance(v, dict):
                stack.extend(v.items())
            else:
                print("%s: %s" % (k, v))

However, Python actually detects cycles in nested dictionary:

    print dic
    {'key2': {'key2.1': 'value2', 'key2.3': {...}, 
       'key2.2': {'key1.1': 'value1'}}, 'key1': {'key1.1': 'value1'}}

"{...}" is where a cycle is detected.

As requested by Moondra this is a way to avoid cycles (DFS):

def myprint(d): 
    stack = list(d.items()) 
    visited = set() 
    while stack: 
        k, v = stack.pop() 
        if isinstance(v, dict): 
            if k not in visited: 
                stack.extend(v.items()) 
        else: 
            print("%s: %s" % (k, v)) 
        visited.add(k)

Bootstrap modal in React.js

I was recently looking for a nice solution to this without adding React-Bootstrap to my project (as Bootstrap 4 is about to be released).

This is my solution: https://jsfiddle.net/16j1se1q/1/

let Modal = React.createClass({
    componentDidMount(){
        $(this.getDOMNode()).modal('show');
        $(this.getDOMNode()).on('hidden.bs.modal', this.props.handleHideModal);
    },
    render(){
        return (
          <div className="modal fade">
            <div className="modal-dialog">
              <div className="modal-content">
                <div className="modal-header">
                  <button type="button" className="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>
                  <h4 className="modal-title">Modal title</h4>
                </div>
                <div className="modal-body">
                  <p>One fine body&hellip;</p>
                </div>
                <div className="modal-footer">
                  <button type="button" className="btn btn-default" data-dismiss="modal">Close</button>
                  <button type="button" className="btn btn-primary">Save changes</button>
                </div>
              </div>
            </div>
          </div>
        )
    },
    propTypes:{
        handleHideModal: React.PropTypes.func.isRequired
    }
});



let App = React.createClass({
    getInitialState(){
        return {view: {showModal: false}}
    },
    handleHideModal(){
        this.setState({view: {showModal: false}})
    },
    handleShowModal(){
        this.setState({view: {showModal: true}})
    },
    render(){
    return(
        <div className="row">
            <button className="btn btn-default btn-block" onClick={this.handleShowModal}>Open Modal</button>
            {this.state.view.showModal ? <Modal handleHideModal={this.handleHideModal}/> : null}
        </div>
    );
  }
});

React.render(
   <App />,
    document.getElementById('container')
);

The main idea is to only render the Modal component into the React DOM when it is to be shown (in the App components render function). I keep some 'view' state that indicates whether the Modal is currently shown or not.

The 'componentDidMount' and 'componentWillUnmount' callbacks either hide or show the modal (once it is rendered into the React DOM) via Bootstrap javascript functions.

I think this solution nicely follows the React ethos but suggestions are welcome!

How to modify a global variable within a function in bash?

This needs bash 4.1 if you use {fd} or local -n.

The rest should work in bash 3.x I hope. I am not completely sure due to printf %q - this might be a bash 4 feature.

Summary

Your example can be modified as follows to archive the desired effect:

# Add following 4 lines:
_passback() { while [ 1 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; return $1; }
passback() { _passback "$@" "$?"; }
_capture() { { out="$("${@:2}" 3<&-; "$2_" >&3)"; ret=$?; printf "%q=%q;" "$1" "$out"; } 3>&1; echo "(exit $ret)"; }
capture() { eval "$(_capture "$@")"; }

e=2

# Add following line, called "Annotation"
function test1_() { passback e; }
function test1() {
  e=4
  echo "hello"
}

# Change following line to:
capture ret test1 

echo "$ret"
echo "$e"

prints as desired:

hello
4

Note that this solution:

  • Works for e=1000, too.
  • Preserves $? if you need $?

The only bad sideffects are:

  • It needs a modern bash.
  • It forks quite more often.
  • It needs the annotation (named after your function, with an added _)
  • It sacrifices file descriptor 3.
    • You can change it to another FD if you need that.
      • In _capture just replace all occurances of 3 with another (higher) number.

The following (which is quite long, sorry for that) hopefully explains, how to adpot this recipe to other scripts, too.

The problem

d() { let x++; date +%Y%m%d-%H%M%S; }

x=0
d1=$(d)
d2=$(d)
d3=$(d)
d4=$(d)
echo $x $d1 $d2 $d3 $d4

outputs

0 20171129-123521 20171129-123521 20171129-123521 20171129-123521

while the wanted output is

4 20171129-123521 20171129-123521 20171129-123521 20171129-123521

The cause of the problem

Shell variables (or generally speaking, the environment) is passed from parental processes to child processes, but not vice versa.

If you do output capturing, this usually is run in a subshell, so passing back variables is difficult.

Some even tell you, that it is impossible to fix. This is wrong, but it is a long known difficult to solve problem.

There are several ways on how to solve it best, this depends on your needs.

Here is a step by step guide on how to do it.

Passing back variables into the parental shell

There is a way to pass back variables to a parental shell. However this is a dangerous path, because this uses eval. If done improperly, you risk many evil things. But if done properly, this is perfectly safe, provided that there is no bug in bash.

_passback() { while [ 0 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; }

d() { let x++; d=$(date +%Y%m%d-%H%M%S); _passback x d; }

x=0
eval `d`
d1=$d
eval `d`
d2=$d
eval `d`
d3=$d
eval `d`
d4=$d
echo $x $d1 $d2 $d3 $d4

prints

4 20171129-124945 20171129-124945 20171129-124945 20171129-124945

Note that this works for dangerous things, too:

danger() { danger="$*"; passback danger; }
eval `danger '; /bin/echo *'`
echo "$danger"

prints

; /bin/echo *

This is due to printf '%q', which quotes everything such, that you can re-use it in a shell context safely.

But this is a pain in the a..

This does not only look ugly, it also is much to type, so it is error prone. Just one single mistake and you are doomed, right?

Well, we are at shell level, so you can improve it. Just think about an interface you want to see, and then you can implement it.

Augment, how the shell processes things

Let's go a step back and think about some API which allows us to easily express, what we want to do.

Well, what do we want do do with the d() function?

We want to capture the output into a variable. OK, then let's implement an API for exactly this:

# This needs a modern bash 4.3 (see "help declare" if "-n" is present,
# we get rid of it below anyway).
: capture VARIABLE command args..
capture()
{
local -n output="$1"
shift
output="$("$@")"
}

Now, instead of writing

d1=$(d)

we can write

capture d1 d

Well, this looks like we haven't changed much, as, again, the variables are not passed back from d into the parent shell, and we need to type a bit more.

However now we can throw the full power of the shell at it, as it is nicely wrapped in a function.

Think about an easy to reuse interface

A second thing is, that we want to be DRY (Don't Repeat Yourself). So we definitively do not want to type something like

x=0
capture1 x d1 d
capture1 x d2 d
capture1 x d3 d
capture1 x d4 d
echo $x $d1 $d2 $d3 $d4

The x here is not only redundant, it's error prone to always repeate in the correct context. What if you use it 1000 times in a script and then add a variable? You definitively do not want to alter all the 1000 locations where a call to d is involved.

So leave the x away, so we can write:

_passback() { while [ 0 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; }

d() { let x++; output=$(date +%Y%m%d-%H%M%S); _passback output x; }

xcapture() { local -n output="$1"; eval "$("${@:2}")"; }

x=0
xcapture d1 d
xcapture d2 d
xcapture d3 d
xcapture d4 d
echo $x $d1 $d2 $d3 $d4

outputs

4 20171129-132414 20171129-132414 20171129-132414 20171129-132414

This already looks very good. (But there still is the local -n which does not work in oder common bash 3.x)

Avoid changing d()

The last solution has some big flaws:

  • d() needs to be altered
  • It needs to use some internal details of xcapture to pass the output.
    • Note that this shadows (burns) one variable named output, so we can never pass this one back.
  • It needs to cooperate with _passback

Can we get rid of this, too?

Of course, we can! We are in a shell, so there is everything we need to get this done.

If you look a bit closer to the call to eval you can see, that we have 100% control at this location. "Inside" the eval we are in a subshell, so we can do everything we want without fear of doing something bad to the parental shell.

Yeah, nice, so let's add another wrapper, now directly inside the eval:

_passback() { while [ 0 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; }
# !DO NOT USE!
_xcapture() { "${@:2}" > >(printf "%q=%q;" "$1" "$(cat)"); _passback x; }  # !DO NOT USE!
# !DO NOT USE!
xcapture() { eval "$(_xcapture "$@")"; }

d() { let x++; date +%Y%m%d-%H%M%S; }

x=0
xcapture d1 d
xcapture d2 d
xcapture d3 d
xcapture d4 d
echo $x $d1 $d2 $d3 $d4

prints

4 20171129-132414 20171129-132414 20171129-132414 20171129-132414                                                    

However, this, again, has some major drawback:

  • The !DO NOT USE! markers are there, because there is a very bad race condition in this, which you cannot see easily:
    • The >(printf ..) is a background job. So it might still execute while the _passback x is running.
    • You can see this yourself if you add a sleep 1; before printf or _passback. _xcapture a d; echo then outputs x or a first, respectively.
  • The _passback x should not be part of _xcapture, because this makes it difficult to reuse that recipe.
  • Also we have some unneded fork here (the $(cat)), but as this solution is !DO NOT USE! I took the shortest route.

However, this shows, that we can do it, without modification to d() (and without local -n)!

Please note that we not neccessarily need _xcapture at all, as we could have written everyting right in the eval.

However doing this usually isn't very readable. And if you come back to your script in a few years, you probably want to be able to read it again without much trouble.

Fix the race

Now let's fix the race condition.

The trick could be to wait until printf has closed it's STDOUT, and then output x.

There are many ways to archive this:

  • You cannot use shell pipes, because pipes run in different processes.
  • One can use temporary files,
  • or something like a lock file or a fifo. This allows to wait for the lock or fifo,
  • or different channels, to output the information, and then assemble the output in some correct sequence.

Following the last path could look like (note that it does the printf last because this works better here):

_passback() { while [ 0 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; }

_xcapture() { { printf "%q=%q;" "$1" "$("${@:2}" 3<&-; _passback x >&3)"; } 3>&1; }

xcapture() { eval "$(_xcapture "$@")"; }

d() { let x++; date +%Y%m%d-%H%M%S; }

x=0
xcapture d1 d
xcapture d2 d
xcapture d3 d
xcapture d4 d
echo $x $d1 $d2 $d3 $d4

outputs

4 20171129-144845 20171129-144845 20171129-144845 20171129-144845

Why is this correct?

  • _passback x directly talks to STDOUT.
  • However, as STDOUT needs to be captured in the inner command, we first "save" it into FD3 (you can use others, of course) with '3>&1' and then reuse it with >&3.
  • The $("${@:2}" 3<&-; _passback x >&3) finishes after the _passback, when the subshell closes STDOUT.
  • So the printf cannot happen before the _passback, regardless how long _passback takes.
  • Note that the printf command is not executed before the complete commandline is assembled, so we cannot see artefacts from printf, independently how printf is implemented.

Hence first _passback executes, then the printf.

This resolves the race, sacrificing one fixed file descriptor 3. You can, of course, choose another file descriptor in the case, that FD3 is not free in your shellscript.

Please also note the 3<&- which protects FD3 to be passed to the function.

Make it more generic

_capture contains parts, which belong to d(), which is bad, from a reusability perspective. How to solve this?

Well, do it the desparate way by introducing one more thing, an additional function, which must return the right things, which is named after the original function with _ attached.

This function is called after the real function, and can augment things. This way, this can be read as some annotation, so it is very readable:

_passback() { while [ 0 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; }
_capture() { { printf "%q=%q;" "$1" "$("${@:2}" 3<&-; "$2_" >&3)"; } 3>&1; }
capture() { eval "$(_capture "$@")"; }

d_() { _passback x; }
d() { let x++; date +%Y%m%d-%H%M%S; }

x=0
capture d1 d
capture d2 d
capture d3 d
capture d4 d
echo $x $d1 $d2 $d3 $d4

still prints

4 20171129-151954 20171129-151954 20171129-151954 20171129-151954

Allow access to the return-code

There is only on bit missing:

v=$(fn) sets $? to what fn returned. So you probably want this, too. It needs some bigger tweaking, though:

# This is all the interface you need.
# Remember, that this burns FD=3!
_passback() { while [ 1 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; return $1; }
passback() { _passback "$@" "$?"; }
_capture() { { out="$("${@:2}" 3<&-; "$2_" >&3)"; ret=$?; printf "%q=%q;" "$1" "$out"; } 3>&1; echo "(exit $ret)"; }
capture() { eval "$(_capture "$@")"; }

# Here is your function, annotated with which sideffects it has.
fails_() { passback x y; }
fails() { x=$1; y=69; echo FAIL; return 23; }

# And now the code which uses it all
x=0
y=0
capture wtf fails 42
echo $? $x $y $wtf

prints

23 42 69 FAIL

There is still a lot room for improvement

  • _passback() can be elmininated with passback() { set -- "$@" "$?"; while [ 1 -lt $# ]; do printf '%q=%q;' "$1" "${!1}"; shift; done; return $1; }
  • _capture() can be eliminated with capture() { eval "$({ out="$("${@:2}" 3<&-; "$2_" >&3)"; ret=$?; printf "%q=%q;" "$1" "$out"; } 3>&1; echo "(exit $ret)")"; }

  • The solution pollutes a file descriptor (here 3) by using it internally. You need to keep that in mind if you happen to pass FDs.
    Note thatbash 4.1 and above has {fd} to use some unused FD.
    (Perhaps I will add a solution here when I come around.)
    Note that this is why I use to put it in separate functions like _capture, because stuffing this all into one line is possible, but makes it increasingly harder to read and understand

  • Perhaps you want to capture STDERR of the called function, too. Or you want to even pass in and out more than one filedescriptor from and to variables.
    I have no solution yet, however here is a way to catch more than one FD, so we can probably pass back the variables this way, too.

Also do not forget:

This must call a shell function, not an external command.

There is no easy way to pass environment variables out of external commands. (With LD_PRELOAD= it should be possible, though!) But this then is something completely different.

Last words

This is not the only possible solution. It is one example to a solution.

As always you have many ways to express things in the shell. So feel free to improve and find something better.

The solution presented here is quite far from being perfect:

  • It was nearly not testet at all, so please forgive typos.
  • There is a lot of room for improvement, see above.
  • It uses many features from modern bash, so probably is hard to port to other shells.
  • And there might be some quirks I haven't thought about.

However I think it is quite easy to use:

  • Add just 4 lines of "library".
  • Add just 1 line of "annotation" for your shell function.
  • Sacrifices just one file descriptor temporarily.
  • And each step should be easy to understand even years later.

Loop through an array in JavaScript

Introduction

Since my time in college, I've programmed in Java, JavaScript, Pascal, ABAP, PHP, Progress 4GL, C/C++ and possibly a few other languages I can't think of right now.

While they all have their own linguistic idiosyncrasies, each of these languages share many of the same basic concepts. Such concepts include procedures / functions, IF-statements, FOR-loops, and WHILE-loops.


A traditional for-loop

A traditional for loop has three components:

  1. The initialization: executed before the look block is executed the first time
  2. The condition: checks a condition every time before the loop block is executed, and quits the loop if false
  3. The afterthought: performed every time after the loop block is executed

These three components are separated from each other by a ; symbol. Content for each of these three components is optional, which means that the following is the most minimal for loop possible:

for (;;) {
    // Do stuff
}

Of course, you will need to include an if(condition === true) { break; } or an if(condition === true) { return; } somewhere inside that for-loop to get it to stop running.

Usually, though, the initialization is used to declare an index, the condition is used to compare that index with a minimum or maximum value, and the afterthought is used to increment the index:

for (var i = 0, length = 10; i < length; i++) {
    console.log(i);
}

Using a traditional for loop to loop through an array

The traditional way to loop through an array, is this:

for (var i = 0, length = myArray.length; i < length; i++) {
    console.log(myArray[i]);
}

Or, if you prefer to loop backwards, you do this:

for (var i = myArray.length - 1; i > -1; i--) {
    console.log(myArray[i]);
}

There are, however, many variations possible, like for example this one:

for (var key = 0, value = myArray[key], length = myArray.length; key < length; value = myArray[++key]) {
    console.log(value);
}

...or this one...

var i = 0, length = myArray.length;
for (; i < length;) {
    console.log(myArray[i]);
    i++;
}

...or this one:

var key = 0, value;
for (; value = myArray[key++];){
    console.log(value);
}

Whichever works best is largely a matter of both personal taste and the specific use case you're implementing.

Note that each of these variations is supported by all browsers, including very very old ones!


A while loop

One alternative to a for loop is a while loop. To loop through an array, you could do this:

var key = 0;
while(value = myArray[key++]){
    console.log(value);
}

Like traditional for loops, while loops are supported by even the oldest of browsers.

Also, note that every while loop can be rewritten as a for loop. For example, the while loop hereabove behaves the exact same way as this for-loop:

for(var key = 0; value = myArray[key++];){
    console.log(value);
}

For...in and for...of

In JavaScript, you can also do this:

for (i in myArray) {
    console.log(myArray[i]);
}

This should be used with care, however, as it doesn't behave the same as a traditional for loop in all cases, and there are potential side-effects that need to be considered. See Why is using "for...in" for array iteration a bad idea? for more details.

As an alternative to for...in, there's now also for for...of. The following example shows the difference between a for...of loop and a for...in loop:

var myArray = [3, 5, 7];
myArray.foo = "hello";

for (var i in myArray) {
  console.log(i); // logs 0, 1, 2, "foo"
}

for (var i of myArray) {
  console.log(i); // logs 3, 5, 7
}

Additionally, you need to consider that no version of Internet Explorer supports for...of (Edge 12+ does) and that for...in requires at least Internet Explorer 10.


Array.prototype.forEach()

An alternative to for-loops is Array.prototype.forEach(), which uses the following syntax:

myArray.forEach(function(value, key, myArray) {
    console.log(value);
});

Array.prototype.forEach() is supported by all modern browsers, as well as Internet Explorer 9 and later.


Libraries

Finally, many utility libraries also have their own foreach variation. AFAIK, the three most popular ones are these:

jQuery.each(), in jQuery:

$.each(myArray, function(key, value) {
    console.log(value);
});

_.each(), in Underscore.js:

_.each(myArray, function(value, key, myArray) {
    console.log(value);
});

_.forEach(), in Lodash:

_.forEach(myArray, function(value, key) {
    console.log(value);
});

Unable to get provider com.google.firebase.provider.FirebaseInitProvider

Add this to your module-level build.gradle :

android {               
defaultConfig {
    ....
    multiDexEnabled true
}
...
}

dependencies {
    compile 'com.android.support:multidex:1.0.1'
    .........
}

If you override Application class then extend it from MultiDexApplication :

YourApplicationClass extends MultiDexApplication

If you cant extend it from MultiDexApplication class then override attachBaseContext() method as following :

protected void attachBaseContext(Context base) {
     super.attachBaseContext(context);
     Multidex.install(this);
  }

And dont run anything before MultiDex.install(this) is executed.

If you dont override the Application class simply edit your manifest file as following :

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    .......>
     <application
         ......
            android:name="android.support.multidex.MultiDexApplication" >
        ...
    </application>
    ......
</manifest>

How to differ sessions in browser-tabs?

You have to realize that server-side sessions are an artificial add-on to HTTP. Since HTTP is stateless, the server needs to somehow recognize that a request belongs to a particular user it knows and has a session for. There are 2 ways to do this:

  • Cookies. The cleaner and more popular method, but it means that all browser tabs and windows by one user share the session - IMO this is in fact desirable, and I would be very annoyed at a site that made me login for each new tab, since I use tabs very intensively
  • URL rewriting. Any URL on the site has a session ID appended to it. This is more work (you have to do something everywhere you have a site-internal link), but makes it possible to have separate sessions in different tabs, though tabs opened through link will still share the session. It also means the user always has to log in when he comes to your site.

What are you trying to do anyway? Why would you want tabs to have separate sessions? Maybe there's a way to achieve your goal without using sessions at all?

Edit: For testing, other solutions can be found (such as running several browser instances on separate VMs). If one user needs to act in different roles at the same time, then the "role" concept should be handled in the app so that one login can have several roles. You'll have to decide whether this, using URL rewriting, or just living with the current situation is more acceptable, because it's simply not possible to handle browser tabs separately with cookie-based sessions.

use mysql SUM() in a WHERE clause

In general, a condition in the WHERE clause of an SQL query can reference only a single row. The context of a WHERE clause is evaluated before any order has been defined by an ORDER BY clause, and there is no implicit order to an RDBMS table.

You can use a derived table to join each row to the group of rows with a lesser id value, and produce the sum of each sum group. Then test where the sum meets your criterion.

CREATE TABLE MyTable ( id INT PRIMARY KEY, cash INT );

INSERT INTO MyTable (id, cash) VALUES
  (1, 200), (2, 301), (3, 101), (4, 700);

SELECT s.*
FROM (
  SELECT t.id, SUM(prev.cash) AS cash_sum
  FROM MyTable t JOIN MyTable prev ON (t.id > prev.id)
  GROUP BY t.id) AS s
WHERE s.cash_sum >= 500
ORDER BY s.id
LIMIT 1;

Output:

+----+----------+
| id | cash_sum |
+----+----------+
|  3 |      501 |
+----+----------+

Hide div after a few seconds

There's a really simple way to do this.

The problem is that .delay only effects animations, so what you need to do is make .hide() act like an animation by giving it a duration.

$("#whatever").delay().hide(1);

By giving it a nice short duration, it appears to be instant just like the regular .hide function.

The superclass "javax.servlet.http.HttpServlet" was not found on the Java Build Path

I too received the same error as quoted below:

The superclass “javax.servlet.http.HttpServlet” was not found on the Java Build Path.

I followed these steps to resolve the issue:

  1. Right Click on Project
  2. Select Properties
  3. Select Project Facets
  4. Select Apache Tomcat as Runtime server
  5. Click OK

How to error handle 1004 Error with WorksheetFunction.VLookup?

Instead of WorksheetFunction.Vlookup, you can use Application.Vlookup. If you set a Variant equal to this it returns Error 2042 if no match is found. You can then test the variant - cellNum in this case - with IsError:

Sub test()
Dim ws As Worksheet: Set ws = Sheets("2012")
Dim rngLook As Range: Set rngLook = ws.Range("A:M")
Dim currName As String
Dim cellNum As Variant

'within a loop
currName = "Example"
cellNum = Application.VLookup(currName, rngLook, 13, False)
If IsError(cellNum) Then
    MsgBox "no match"
Else
    MsgBox cellNum
End If
End Sub

The Application versions of the VLOOKUP and MATCH functions allow you to test for errors without raising the error. If you use the WorksheetFunction version, you need convoluted error handling that re-routes your code to an error handler, returns to the next statement to evaluate, etc. With the Application functions, you can avoid that mess.

The above could be further simplified using the IIF function. This method is not always appropriate (e.g., if you have to do more/different procedure based on the If/Then) but in the case of this where you are simply trying to determinie what prompt to display in the MsgBox, it should work:

cellNum = Application.VLookup(currName, rngLook, 13, False)
MsgBox IIF(IsError(cellNum),"no match", cellNum)

Consider those methods instead of On Error ... statements. They are both easier to read and maintain -- few things are more confusing than trying to follow a bunch of GoTo and Resume statements.

jQuery: print_r() display equivalent?

$.each(myobject, function(key, element) {
    alert('key: ' + key + '\n' + 'value: ' + element);
});

This does the work for me. :)

Matplotlib legends in subplot

This does what you want and overcomes some of the problems in other answers:

import matplotlib.pyplot as plt

labels = ["HHZ 1", "HHN", "HHE"]
colors = ["r","g","b"]

f,axs = plt.subplots(3, sharex=True, sharey=True)

# ---- loop over axes ----
for i,ax in enumerate(axs):
  axs[i].plot([0,1],[1,0],color=colors[i],label=labels[i])
  axs[i].legend(loc="upper right")

plt.show()

... produces ... subplots

How to store images in mysql database using php

<!-- 
//THIS PROGRAM WILL UPLOAD IMAGE AND WILL RETRIVE FROM DATABASE. UNSING BLOB
(IF YOU HAVE ANY QUERY CONTACT:[email protected])


CREATE TABLE  `images` (
  `id` int(100) NOT NULL AUTO_INCREMENT,
  `name` varchar(100) NOT NULL,
  `image` longblob NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB ;

-->
<!-- this form is user to store images-->
<form action="index.php" method="post"  enctype="multipart/form-data">
Enter the Image Name:<input type="text" name="image_name" id="" /><br />

<input name="image" id="image" accept="image/JPEG" type="file"><br /><br />
<input type="submit" value="submit" name="submit" />
</form>
<br /><br />
<!-- this form is user to display all the images-->
<form action="index.php" method="post"  enctype="multipart/form-data">
Retrive all the images:
<input type="submit" value="submit" name="retrive" />
</form>



<?php
//THIS IS INDEX.PHP PAGE
//connect to database.db name is images
        mysql_connect("", "", "") OR DIE (mysql_error());
        mysql_select_db ("") OR DIE ("Unable to select db".mysql_error());
//to retrive send the page to another page
if(isset($_POST['retrive']))
{
    header("location:search.php");

}

//to upload
if(isset($_POST['submit']))
{
if(isset($_FILES['image'])) {
        $name=$_POST['image_name'];
        $email=$_POST['mail'];
        $fp=addslashes(file_get_contents($_FILES['image']['tmp_name'])); //will store the image to fp
        }
                // our sql query
                $sql = "INSERT INTO images VALUES('null', '{$name}','{$fp}');";
                            mysql_query($sql) or die("Error in Query insert: " . mysql_error());
} 
?>



<?php
//SEARCH.PHP PAGE
    //connect to database.db name = images
         mysql_connect("localhost", "root", "") OR DIE (mysql_error());
        mysql_select_db ("image") OR DIE ("Unable to select db".mysql_error());
//display all the image present in the database

        $msg="";
        $sql="select * from images";
        if(mysql_query($sql))
        {
            $res=mysql_query($sql);
            while($row=mysql_fetch_array($res))
            {
                    $id=$row['id'];
                    $name=$row['name'];
                    $image=$row['image'];

                  $msg.= '<a href="search.php?id='.$id.'"><img src="data:image/jpeg;base64,'.base64_encode($row['image']). ' " />   </a>';

            }
        }
        else
            $msg.="Query failed";
?>
<div>
<?php
echo $msg;
?>

How to sort an array in descending order in Ruby

Simple Solution from ascending to descending and vice versa is:

STRINGS

str = ['ravi', 'aravind', 'joker', 'poker']
asc_string = str.sort # => ["aravind", "joker", "poker", "ravi"]
asc_string.reverse # => ["ravi", "poker", "joker", "aravind"]

DIGITS

digit = [234,45,1,5,78,45,34,9]
asc_digit = digit.sort # => [1, 5, 9, 34, 45, 45, 78, 234]
asc_digit.reverse # => [234, 78, 45, 45, 34, 9, 5, 1]

gradlew command not found?

I use intellj idea and in windows in terminal type: gradlew.bat run it is working for me.

How to display a loading screen while site content loads

There's actually a pretty easy way to do this. The code should be something like:

<script type="test/javascript">

    function showcontent(x){

      if(window.XMLHttpRequest) {
        xmlhttp = new XMLHttpRequest();
      } else {
        xmlhttp = new ActiveXObject('Microsoft.XMLHTTP');
      }

      xmlhttp.onreadystatechange = function() {
        if(xmlhttp.readyState == 1) {
            document.getElementById('content').innerHTML = "<img src='loading.gif' />";
        }
        if(xmlhttp.readyState == 4 && xmlhttp.status == 200) {
          document.getElementById('content').innerHTML = xmlhttp.responseText;
        } 
      }

      xmlhttp.open('POST', x+'.html', true);
      xmlhttp.setRequestHeader('Content-type','application/x-www-form-urlencoded');
      xmlhttp.send(null);

    }

And in the HTML:

<body onload="showcontent(main)"> <!-- onload optional -->
<div id="content"><img src="loading.gif"></div> <!-- leave img out if not onload -->
</body>

I did something like that on my page and it works great.

Python Database connection Close

You might try turning off pooling, which is enabled by default. See this discussion for more information.

import pyodbc
pyodbc.pooling = False
conn = pyodbc.connect('DRIVER=MySQL ODBC 5.1 driver;SERVER=localhost;DATABASE=spt;UID=who;PWD=testest') 

csr = conn.cursor()  
csr.close()
del csr

Send email from localhost running XAMMP in PHP using GMAIL mail server

[sendmail]

smtp_server=smtp.gmail.com  
smtp_port=25  
error_logfile=error.log  
debug_logfile=debug.log  
[email protected] 
auth_password=gmailpassword  
[email protected]

need authenticate username and password of mail then only once can successfully send mail from localhost

CSS selector - element with a given child

Is it possible to select an element if it contains a specific child element?

Unfortunately not yet.

The CSS2 and CSS3 selector specifications do not allow for any sort of parent selection.


A Note About Specification Changes

This is a disclaimer about the accuracy of this post from this point onward. Parent selectors in CSS have been discussed for many years. As no consensus has been found, changes keep happening. I will attempt to keep this answer up-to-date, however be aware that there may be inaccuracies due to changes in the specifications.


An older "Selectors Level 4 Working Draft" described a feature which was the ability to specify the "subject" of a selector. This feature has been dropped and will not be available for CSS implementations.

The subject was going to be the element in the selector chain that would have styles applied to it.

Example HTML
<p><span>lorem</span> ipsum dolor sit amet</p>
<p>consecteture edipsing elit</p>

This selector would style the span element

p span {
    color: red;
}

This selector would style the p element

!p span {
    color: red;
}

A more recent "Selectors Level 4 Editor’s Draft" includes "The Relational Pseudo-class: :has()"

:has() would allow an author to select an element based on its contents. My understanding is it was chosen to provide compatibility with jQuery's custom :has() pseudo-selector*.

In any event, continuing the example from above, to select the p element that contains a span one could use:

p:has(span) {
    color: red;
}

* This makes me wonder if jQuery had implemented selector subjects whether subjects would have remained in the specification.

How to convert interface{} to string?

You need to add type assertion .(string). It is necessary because the map is of type map[string]interface{}:

host := arguments["<host>"].(string) + ":" + arguments["<port>"].(string)

Latest version of Docopt returns Opts object that has methods for conversion:

host, err := arguments.String("<host>")
port, err := arguments.String("<port>")
host_port := host + ":" + port

MySQL: Quick breakdown of the types of joins

Based on your comment, simple definitions of each is best found at W3Schools The first line of each type gives a brief explanation of the join type

  • JOIN: Return rows when there is at least one match in both tables
  • LEFT JOIN: Return all rows from the left table, even if there are no matches in the right table
  • RIGHT JOIN: Return all rows from the right table, even if there are no matches in the left table
  • FULL JOIN: Return rows when there is a match in one of the tables

END EDIT

In a nutshell, the comma separated example you gave of

SELECT * FROM a, b WHERE b.id = a.beeId AND ...

is selecting every record from tables a and b with the commas separating the tables, this can be used also in columns like

SELECT a.beeName,b.* FROM a, b WHERE b.id = a.beeId AND ...

It is then getting the instructed information in the row where the b.id column and a.beeId column have a match in your example. So in your example it will get all information from tables a and b where the b.id equals a.beeId. In my example it will get all of the information from the b table and only information from the a.beeName column when the b.id equals the a.beeId. Note that there is an AND clause also, this will help to refine your results.

For some simple tutorials and explanations on mySQL joins and left joins have a look at Tizag's mySQL tutorials. You can also check out Keith J. Brown's website for more information on joins that is quite good also.

I hope this helps you

Find Process Name by its Process ID

Using only "native" Windows utilities, try the following, where "516" is the process ID that you want the image name for:

for /f "delims=," %a in ( 'tasklist /fi "PID eq 516" /nh /fo:csv' ) do ( echo %~a )
for /f %a in ( 'tasklist /fi "PID eq 516" ^| findstr "516"' ) do ( echo %a )

Or you could use wmic (the Windows Management Instrumentation Command-line tool) and get the full path to the executable:

wmic process where processId=516 get name
wmic process where processId=516 get ExecutablePath

Or you could download Microsoft PsTools, or specifically download just the pslist utility, and use PsList:

for /f %a in ( 'pslist 516 ^| findstr "516"' ) do ( echo %a )

Error message "Unable to install or run the application. The application requires stdole Version 7.0.3300.0 in the GAC"

I had the same problem with a ClickOnce deployment.

I solved the problem by going to the 'Publish' tab in the project properties and then selecting the 'Application Files' button.

I then selected the options:

  • 'File Name' of 'stdole.dll'
  • 'Publish status' to 'Include' and
  • 'Download Group' to 'Required'.

This fixed my problem when I re-published.

I hope this help you :D

How can I suppress column header output for a single SQL statement?

You can fake it like this:

-- with column headings 
select column1, column2 from some_table;

-- without column headings
select column1 as '', column2 as '' from some_table;

Drawing an SVG file on a HTML5 canvas

EDIT Dec 16th, 2019

Path2D is supported by all major browsers now

EDIT November 5th, 2014

You can now use ctx.drawImage to draw HTMLImageElements that have a .svg source in some but not all browsers. Chrome, IE11, and Safari work, Firefox works with some bugs (but nightly has fixed them).

var img = new Image();
img.onload = function() {
    ctx.drawImage(img, 0, 0);
}
img.src = "http://upload.wikimedia.org/wikipedia/commons/d/d2/Svg_example_square.svg";

Live example here. You should see a green square in the canvas. The second green square on the page is the same <svg> element inserted into the DOM for reference.

You can also use the new Path2D objects to draw SVG (string) paths. In other words, you can write:

var path = new Path2D('M 100,100 h 50 v 50 h 50');
ctx.stroke(path);

Live example of that here.


Old posterity answer:

There's nothing native that allows you to natively use SVG paths in canvas. You must convert yourself or use a library to do it for you.

I'd suggest looking in to canvg:

http://code.google.com/p/canvg/

http://canvg.googlecode.com/svn/trunk/examples/index.htm

How to select count with Laravel's fluent query builder?

$count = DB::table('category_issue')->count();

will give you the number of items.

For more detailed information check Fluent Query Builder section in beautiful Laravel Documentation.

Running stages in parallel with Jenkins workflow / pipeline

I have just tested the following pipeline and it works

parallel firstBranch: {
    stage ('Starting Test') 
    {
        build job: 'test1', parameters: [string(name: 'Environment', value: "$env.Environment")]
    }
}, secondBranch: {
    stage ('Starting Test2') 
    {
        build job: 'test2', parameters: [string(name: 'Environment', value: "$env.Environment")]
    }
}

This Job named 'trigger-test' accepts one parameter named 'Environment'

Job 'test1' and 'test2' are simple jobs:

Example for 'test1'

  • One parameter named 'Environment'
  • Pipeline : echo "$env.Environment-TEST1"

On execution, I am able to see both stages running in the same time

Convert JSONArray to String Array

You might want to take a look at JSONArray.toList(), which returns a List containing Maps and Lists, which represent your JSON structure. So you can use it with Java Streams like this:

JSONArray array = new JSONArray(jsonString);
List<String> result = array.toList().stream()
        .filter(Map.class::isInstance)
        .map(Map.class::cast)
        .map(o -> o.get("name"))
        .filter(String.class::isInstance)
        .map(String.class::cast)
        .collect(Collectors.toList());

This might just be useful even for more complex objects.

Alternatively you can just use an IntStream to iterate over all items in the JSONArray and map all names:

JSONArray array = new JSONArray(jsonString);
List<String> result = IntStream.range(0, array.length())
        .mapToObj(array::getJSONObject)
        .map(o -> o.getString("name"))
        .collect(Collectors.toList());

Passing html values into javascript functions

Try: if(parseInt(order)>0){....

How to append to a file in Node?

Besides appendFile, you can also pass a flag in writeFile to append data to an existing file.

fs.writeFile('log.txt', 'Hello Node',  {'flag':'a'},  function(err) {
    if (err) {
        return console.error(err);
    }
});

By passing flag 'a', data will be appended at the end of the file.

How to use GROUP BY to concatenate strings in SQL Server?

Don't need a cursor... a while loop is sufficient.

------------------------------
-- Setup
------------------------------

DECLARE @Source TABLE
(
  id int,
  Name varchar(30),
  Value int
)

DECLARE @Target TABLE
(
  id int,
  Result varchar(max) 
)


INSERT INTO @Source(id, Name, Value) SELECT 1, 'A', 4
INSERT INTO @Source(id, Name, Value) SELECT 1, 'B', 8
INSERT INTO @Source(id, Name, Value) SELECT 2, 'C', 9


------------------------------
-- Technique
------------------------------

INSERT INTO @Target (id)
SELECT id
FROM @Source
GROUP BY id

DECLARE @id int, @Result varchar(max)
SET @id = (SELECT MIN(id) FROM @Target)

WHILE @id is not null
BEGIN
  SET @Result = null

  SELECT @Result =
    CASE
      WHEN @Result is null
      THEN ''
      ELSE @Result + ', '
    END + s.Name + ':' + convert(varchar(30),s.Value)
  FROM @Source s
  WHERE id = @id

  UPDATE @Target
  SET Result = @Result
  WHERE id = @id

  SET @id = (SELECT MIN(id) FROM @Target WHERE @id < id)
END

SELECT *
FROM @Target

How can I get the current network interface throughput statistics on Linux/UNIX?

I find dstat to be quite good. Has to be installed though. Gives you way more information than you need. Netstat will give you packet rates but not bandwith also. netstat -s

How to iterate object in JavaScript?

Something like that:

var dictionary = {"data":[{"id":"0","name":"ABC"},{"id":"1", "name":"DEF"}], "images": [{"id":"0","name":"PQR"},{"id":"1","name":"xyz"}]};

for (item in dictionary) {
  for (subItem in dictionary[item]) {
     console.log(dictionary[item][subItem].id);
     console.log(dictionary[item][subItem].name);
  }
}

ExpressJS - throw er Unhandled error event

We do get similar error when we sometimes run our express app. We have to follow the same in that case. We need to check if its running in any terminal. If you want to find and kill process, follow these steps:

  • ps aux | grep node
  • Find the process ID (second from the left):
  • kill -9 PRCOCESS_ID

OR

Use a single command to close all the running node processes.

ps aux | awk '/node/{print $2}' | xargs kill -9

How do I expire a PHP session after 30 minutes?

Use the session_set_cookie_paramsfunciton for make this.

Is necessary calling this function before session_start() call.

Try this:

$lifetime = strtotime('+30 minutes', 0);

session_set_cookie_params($lifetime);

session_start();

See more in: http://php.net/manual/function.session-set-cookie-params.php

Is it possible to make an HTML anchor tag not clickable/linkable using CSS?

A more un-obtrusive way (assuming you use jQuery):

HTML:

<a id="my-link" href="page.html">page link</a>

Javascript:

$('#my-link').click(function(e)
{
    e.preventDefault();
});

The advantage of this is the clean separation between logic and presentation. If one day you decide that this link would do something else, you don't have to mess with the markup, just the JS.

How to turn on front flash light programmatically in Android?

For this problem you should:

  1. Check whether the flashlight is available or not?

  2. If so then Turn Off/On

  3. If not then you can do whatever, according to your app needs.

For Checking availability of flash in the device:

You can use the following:

 context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);

which will return true if a flash is available, false if not.

See:
http://developer.android.com/reference/android/content/pm/PackageManager.html for more information.

For turning on/off flashlight:

I googled out and got this about android.permission.FLASHLIGHT. Android manifests' permission looks promising:

 <!-- Allows access to the flashlight -->
 <permission android:name="android.permission.FLASHLIGHT"
             android:permissionGroup="android.permission-group.HARDWARE_CONTROLS"
             android:protectionLevel="normal"
             android:label="@string/permlab_flashlight"
             android:description="@string/permdesc_flashlight" />

Then make use of Camera and set Camera.Parameters. The main parameter used here is FLASH_MODE_TORCH.

eg.

Code Snippet to turn on camera flashlight.

Camera cam = Camera.open();     
Parameters p = cam.getParameters();
p.setFlashMode(Parameters.FLASH_MODE_TORCH);
cam.setParameters(p);
cam.startPreview();

Code snippet to turn off camera led light.

  cam.stopPreview();
  cam.release();

I just found a project that uses this permission. Check quick-settings' src code. here http://code.google.com/p/quick-settings/ (Note: This link is now broken)

For Flashlight directly look http://code.google.com/p/quick-settings/source/browse/trunk/quick-settings/#quick-settings/src/com/bwx/bequick/flashlight (Note: This link is now broken)

Update6 You could also try to add a SurfaceView as described in this answer LED flashlight on Galaxy Nexus controllable by what API? This seems to be a solution that works on many phones.

Update 5 Major Update

I have found an alternative Link (for the broken links above): http://www.java2s.com/Open-Source/Android/Tools/quick-settings/com.bwx.bequick.flashlight.htm You can now use this link. [Update: 14/9/2012 This link is now broken]

Update 1

Another OpenSource Code : http://code.google.com/p/torch/source/browse/

Update 2

Example showing how to enable the LED on a Motorola Droid: http://code.google.com/p/droidled/

Another Open Source Code :

http://code.google.com/p/covedesigndev/
http://code.google.com/p/search-light/

Update 3 (Widget for turning on/off camera led)

If you want to develop a widget that turns on/off your camera led, then you must refer my answer Widget for turning on/off camera flashlight in android..

Update 4

If you want to set the intensity of light emerging from camera LED you can refer Can I change the LED intensity of an Android device? full post. Note that only rooted HTC devices support this feature.

** Issues:**

There are also some problems while turning On/Off flashlight. eg. for the devices not having FLASH_MODE_TORCH or even if it has, then flashlight does not turn ON etc.

Typically Samsung creates a lot of problems.

You can refer to problems in the given below list:

Use camera flashlight in Android

Turn ON/OFF Camera LED/flash light in Samsung Galaxy Ace 2.2.1 & Galaxy Tab

Converting java.util.Properties to HashMap<String,String>

Properties implements Map<Object, Object> - not Map<String, String>.

You're trying to call this constructor:

public HashMap(Map<? extends K,? extends V> m)

... with K and V both as String.

But Map<Object, Object> isn't a Map<? extends String, ? extends String>... it can contain non-string keys and values.

This would work:

Map<Object, Object> map = new HashMap<Object, Object>();

... but it wouldn't be as useful to you.

Fundamentally, Properties should never have been made a subclass of HashTable... that's the problem. Since v1, it's always been able to store non-String keys and values, despite that being against the intention. If composition had been used instead, the API could have only worked with string keys/values, and all would have been well.

You may want something like this:

Map<String, String> map = new HashMap<String, String>();
for (String key : properties.stringPropertyNames()) {
    map.put(key, properties.getProperty(key));
}

How do I get a file extension in PHP?

Sometimes it's useful to not to use pathinfo($path, PATHINFO_EXTENSION). For example:

$path = '/path/to/file.tar.gz';

echo ltrim(strstr($path, '.'), '.'); // tar.gz
echo pathinfo($path, PATHINFO_EXTENSION); // gz

Also note that pathinfo fails to handle some non-ASCII characters (usually it just suppresses them from the output). In extensions that usually isn't a problem, but it doesn't hurt to be aware of that caveat.

Recommended way to get hostname in Java

As others have noted, getting the hostname based on DNS resolution is unreliable.

Since this question is unfortunately still relevant in 2018, I'd like to share with you my network-independent solution, with some test runs on different systems.

The following code tries to do the following:

  • On Windows

    1. Read the COMPUTERNAME environment variable through System.getenv().

    2. Execute hostname.exe and read the response

  • On Linux

    1. Read the HOSTNAME environment variable through System.getenv()

    2. Execute hostname and read the response

    3. Read /etc/hostname (to do this I'm executing cat since the snippet already contains code to execute and read. Simply reading the file would be better, though).

The code:

public static void main(String[] args) throws IOException {
    String os = System.getProperty("os.name").toLowerCase();

    if (os.contains("win")) {
        System.out.println("Windows computer name through env:\"" + System.getenv("COMPUTERNAME") + "\"");
        System.out.println("Windows computer name through exec:\"" + execReadToString("hostname") + "\"");
    } else if (os.contains("nix") || os.contains("nux") || os.contains("mac os x")) {
        System.out.println("Unix-like computer name through env:\"" + System.getenv("HOSTNAME") + "\"");
        System.out.println("Unix-like computer name through exec:\"" + execReadToString("hostname") + "\"");
        System.out.println("Unix-like computer name through /etc/hostname:\"" + execReadToString("cat /etc/hostname") + "\"");
    }
}

public static String execReadToString(String execCommand) throws IOException {
    try (Scanner s = new Scanner(Runtime.getRuntime().exec(execCommand).getInputStream()).useDelimiter("\\A")) {
        return s.hasNext() ? s.next() : "";
    }
}

Results for different operating systems:

macOS 10.13.2

Unix-like computer name through env:"null"
Unix-like computer name through exec:"machinename
"
Unix-like computer name through /etc/hostname:""

OpenSuse 13.1

Unix-like computer name through env:"machinename"
Unix-like computer name through exec:"machinename
"
Unix-like computer name through /etc/hostname:""

Ubuntu 14.04 LTS This one is kinda strange since echo $HOSTNAME returns the correct hostname, but System.getenv("HOSTNAME") does not:

Unix-like computer name through env:"null"
Unix-like computer name through exec:"machinename
"
Unix-like computer name through /etc/hostname:"machinename
"

EDIT: According to legolas108, System.getenv("HOSTNAME") works on Ubuntu 14.04 if you run export HOSTNAME before executing the Java code.

Windows 7

Windows computer name through env:"MACHINENAME"
Windows computer name through exec:"machinename
"

Windows 10

Windows computer name through env:"MACHINENAME"
Windows computer name through exec:"machinename
"

The machine names have been replaced but I kept the capitalization and structure. Note the extra newline when executing hostname, you might have to take it into account in some cases.

How do you install GLUT and OpenGL in Visual Studio 2012?

  1. Create a empty win32 console application c++
  2. Download a package called NupenGL Core from Nuget package manager (PM->"Install-Package nupengl.core") except glm everything is configured
  3. create Source.cpp and start working Happy Coding

Oracle - Insert New Row with Auto Incremental ID

the complete know how, i have included a example of the triggers and sequence

create table temasforo(
idtemasforo NUMBER(5) PRIMARY KEY,
autor       VARCHAR2(50) NOT NULL,
fecha       DATE DEFAULT (sysdate),
asunto      LONG  );

create sequence temasforo_seq
  start with 1
  increment by 1
  nomaxvalue;

create or replace
trigger temasforo_trigger
  before insert on temasforo
  referencing OLD as old NEW as new
  for each row
  begin
      :new.idtemasforo:=temasforo_seq.nextval;
    end;

reference: http://thenullpointerexceptionx.blogspot.mx/2013/06/llaves-primarias-auto-incrementales-en.html

Reading PDF documents in .Net

iText is the best library I know. Originally written in Java, there is a .NET port as well.

See http://www.ujihara.jp/iTextdotNET/en/

How to select all checkboxes with jQuery?

 $(function() {  
$('#select_all').click(function() {
    var checkboxes = $(this).closest('form').find(':checkbox');
    if($(this).is(':checked')) {
        checkboxes.attr('checked', 'checked');
    } else {
        checkboxes.removeAttr('checked');
    }
});
    });

How do I fit an image (img) inside a div and keep the aspect ratio?

You will need some JavaScript to prevent cropping if you don't know the dimension of the image at the time you're writing the css.

HTML & JavaScript

<div id="container">
    <img src="something.jpg" alt="" />
</div>

<script type="text/javascript">
(function() {

var img = document.getElementById('container').firstChild;
img.onload = function() {
    if(img.height > img.width) {
        img.height = '100%';
        img.width = 'auto';
    }
};

}());
</script>

CSS

#container {
   width: 48px;
   height: 48px;
}

#container img {
   width: 100%;
}

If you use a JavaScript Library you might want to take advantage of it.

Best way to import Observable from rxjs

One thing I've learnt the hard way is being consistent

Watch out for mixing:

 import { BehaviorSubject } from "rxjs";

with

 import { BehaviorSubject } from "rxjs/BehaviorSubject";

This will probably work just fine UNTIL you try to pass the object to another class (where you did it the other way) and then this can fail

 (myBehaviorSubject instanceof Observable)

It fails because the prototype chain will be different and it will be false.

I can't pretend to understand exactly what is happening but sometimes I run into this and need to change to the longer format.

How to convert byte array to string and vice versa?

You can use simple for loop for conversion:

public void byteArrToString(){
   byte[] b = {'a','b','$'};
   String str = ""; 
   for(int i=0; i<b.length; i++){
       char c = (char) b[i];
       str+=c;
   }
   System.out.println(str);
}

How to do a PUT request with curl?

Quick Answer:

In a single line, the curl command would be:

a) If sending form data:

curl -X PUT -H "Content-Type: multipart/form-data;" -F "key1=val1" "YOUR_URI"

b) If sending raw data as json:

curl -X PUT -H "Content-Type: application/json" -d '{"key1":"value"}' "YOUR_URI"

c) If sending a file with a POST request:

curl -X POST "YOUR_URI" -F 'file=@/file-path.csv'

Alternative solution:

You can use the POSTMAN app from Chrome Store to get the equivalent cURL request. This is especially useful when writing more complicated requests.

For the request with other formats or for different clients like java, PHP, you can check out POSTMAN/comment below.

POSTMAN to get the request code

Accessing JSON elements

'temp_C' is a key inside dictionary that is inside a list that is inside a dictionary

This way works:

wjson['data']['current_condition'][0]['temp_C']
>> '10'

"Repository does not have a release file" error

#For Unable to 'apt update' my Ubuntu 19.04

The repositories for older releases that are not supported (like 11.04, 11.10 and 13.04) get moved to an archive server. There are repositories available at http://old-releases.ubuntu.com.

first break up this file

cp /etc/apt/sources.list /etc/apt/sources.list.bak sudo sed -i -re 's/([a-z]{2}.)?archive.ubuntu.com|security.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list

then

sudo apt-get update && sudo apt-get dist-upgrade

A monad is just a monoid in the category of endofunctors, what's the problem?

That particular phrasing is by James Iry, from his highly entertaining Brief, Incomplete and Mostly Wrong History of Programming Languages, in which he fictionally attributes it to Philip Wadler.

The original quote is from Saunders Mac Lane in Categories for the Working Mathematician, one of the foundational texts of Category Theory. Here it is in context, which is probably the best place to learn exactly what it means.

But, I'll take a stab. The original sentence is this:

All told, a monad in X is just a monoid in the category of endofunctors of X, with product × replaced by composition of endofunctors and unit set by the identity endofunctor.

X here is a category. Endofunctors are functors from a category to itself (which is usually all Functors as far as functional programmers are concerned, since they're mostly dealing with just one category; the category of types - but I digress). But you could imagine another category which is the category of "endofunctors on X". This is a category in which the objects are endofunctors and the morphisms are natural transformations.

And of those endofunctors, some of them might be monads. Which ones are monads? Exactly the ones which are monoidal in a particular sense. Instead of spelling out the exact mapping from monads to monoids (since Mac Lane does that far better than I could hope to), I'll just put their respective definitions side by side and let you compare:

A monoid is...

  • A set, S
  • An operation, • : S × S ? S
  • An element of S, e : 1 ? S

...satisfying these laws:

  • (a • b) • c = a • (b • c), for all a, b and c in S
  • e • a = a • e = a, for all a in S

A monad is...

  • An endofunctor, T : X ? X (in Haskell, a type constructor of kind * -> * with a Functor instance)
  • A natural transformation, µ : T × T ? T, where × means functor composition (µ is known as join in Haskell)
  • A natural transformation, ? : I ? T, where I is the identity endofunctor on X (? is known as return in Haskell)

...satisfying these laws:

  • µ ° Tµ = µ ° µT
  • µ ° T? = µ ° ?T = 1 (the identity natural transformation)

With a bit of squinting you might be able to see that both of these definitions are instances of the same abstract concept.

Global variables in R

I found a solution for how to set a global variable in a mailinglist posting via assign:

a <- "old"
test <- function () {
   assign("a", "new", envir = .GlobalEnv)
}
test()
a  # display the new value

C# Switch-case string starting with

Short answer: No.

The switch statement takes an expression that is only evaluated once. Based on the result, another piece of code is executed.

So what? => String.StartsWith is a function. Together with a given parameter, it is an expression. However, for your case you need to pass a different parameter for each case, so it cannot be evaluated only once.

Long answer #1 has been given by others.

Long answer #2:

Depending on what you're trying to achieve, you might be interested in the Command Pattern/Chain-of-responsibility pattern. Applied to your case, each piece of code would be represented by an implementation of a Command. In addition to the execute method, the command can provide a boolean Accept method, which checks whether the given string starts with the respective parameter.

Advantage: Instead of your hardcoded switch statement, hardcoded StartsWith evaluations and hardcoded strings, you'd have lot more flexibility.

The example you gave in your question would then look like this:

var commandList = new List<Command>() { new MyABCCommand() };

foreach (Command c in commandList)
{
    if (c.Accept(mystring))
    {
        c.Execute(mystring);
        break;
    }
}

class MyABCCommand : Command
{
    override bool Accept(string mystring)
    {
        return mystring.StartsWith("abc");
    }
}    

Preventing twitter bootstrap carousel from auto sliding on page load

Below are the list of parameters for bootstrap carousel. Like Interval, pause, wrap:

enter image description here

For more details refer this link:

http://www.w3schools.com/bootstrap/bootstrap_ref_js_carousel.asp

Hope this will help you :)

Note: This is for further help. I mean how you can customise or change default behaviour once carousel is loaded.

IllegalMonitorStateException on wait() call

In order to deal with the IllegalMonitorStateException, you must verify that all invocations of the wait, notify and notifyAll methods are taking place only when the calling thread owns the appropriate monitor. The most simple solution is to enclose these calls inside synchronized blocks. The synchronization object that shall be invoked in the synchronized statement is the one whose monitor must be acquired.

Here is the simple example for to understand the concept of monitor

public class SimpleMonitorState {

    public static void main(String args[]) throws InterruptedException {

        SimpleMonitorState t = new SimpleMonitorState();
        SimpleRunnable m = new SimpleRunnable(t);
        Thread t1 = new Thread(m);
        t1.start();
        t.call();

    }

    public void call() throws InterruptedException {
        synchronized (this) {
            wait();
            System.out.println("Single by Threads ");
        }
    }

}

class SimpleRunnable implements Runnable {

    SimpleMonitorState t;

    SimpleRunnable(SimpleMonitorState t) {
        this.t = t;
    }

    @Override
    public void run() {

        try {
            // Sleep
            Thread.sleep(10000);
            synchronized (this.t) {
                this.t.notify();
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

Difference between Select Unique and Select Distinct

select unique is not valid syntax for what you are trying to do

you want to use either select distinct or select distinctrow

And actually, you don't even need distinct/distinctrow in what you are trying to do. You can eliminate duplicates by choosing the appropriate union statement parameters.

the below query by itself will only provide distinct values

select col from table1 
union 
select col from table2

if you did want duplicates you would have to do

select col from table1 
union all
select col from table2

How do I hide the status bar in a Swift iOS app?

Update for iOS 10 / Swift 3.0

No longer a function, now a property...

override var prefersStatusBarHidden: Bool {
    return true
}

React Native version mismatch

In my case installing a new virtual device helped. Now I am using 1 device per app.

How do I format a number with commas in T-SQL?

I'd recommend Replace in lieu of Substring to avoid string length issues:

REPLACE(CONVERT(varchar(20), (CAST(SUM(table.value) AS money)), 1), '.00', '')

Pass values of checkBox to controller action in asp.net mvc4

None of the previous solutions worked for me. Finally I found that the action should be coded as:

public ActionResult Index(string MyCheck = null)

and then, when checked the passed value was "on", not "true". Else, it is always null.

Hope it helps somebody!

I can't delete a remote master branch on git

To answer the question literally (since GitHub is not in the question title), also be aware of this post over on superuser. EDIT: Answer copied here in relevant part, slightly modified for clarity in square brackets:

You're getting rejected because you're trying to delete the branch that your origin has currently "checked out".

If you have direct access to the repo, you can just open up a shell [in the bare repo] directory and use good old git branch to see what branch origin is currently on. To change it to another branch, you have to use git symbolic-ref HEAD refs/heads/another-branch.

Add image in title bar

You'll have to use a favicon for your page. put this in the head-tag: <link rel="shortcut icon" href="/favicon.png" type="image/png">

where favicon.png is preferably a 16x16 png image.

source: Adding a favicon to a static HTML page

Update date + one year in mysql

This post helped me today, but I had to experiment to do what I needed. Here is what I found.

Should you want to add more complex time periods, for example 1 year and 15 days, you can use

UPDATE tablename SET datefieldname = curdate() + INTERVAL 15 DAY + INTERVAL 1 YEAR;

I found that using DATE_ADD doesn't allow for adding more than one interval. And there is no YEAR_DAYS interval keyword, though there are others that combine time periods. If you are adding times, use now() rather than curdate().

How do you add an SDK to Android Studio?

You have to put your SDK's in a given directory or .app directory. You have to do it in finder while you are out of the application i'm assuming, but personally I'd use terminal in Mac instead of doing it in the App itself or finder. According to Google:

On Windows and Mac, the individual tools and other SDK packages are saved within the Android Studio application directory. To access the tools directly, use a terminal to navigate into the application and locate the sdk/ directory. For example:

 Windows: \Users\<user>\AppData\Local\Android\android-studio\sdk\
 Mac: /Applications/Android\ Studio.app/sdk/

JavaScript: Object Rename Key

I would say that it would be better from a conceptual point of view to just leave the old object (the one from the web service) as it is, and put the values you need in a new object. I'm assuming you are extracting specific fields at one point or another anyway, if not on the client, then at least on the server. The fact that you chose to use field names that are the same as those from the web service, only lowercase, doesn't really change this. So, I'd advise to do something like this:

var myObj = {
    field1: theirObj.FIELD1, 
    field2: theirObj.FIELD2,
    (etc)
}

Of course, I'm making all kinds of assumptions here, which may not be true. If this doesn't apply to you, or if it's too slow (is it? I haven't tested, but I imagine the difference gets smaller as the number of fields increases), please ignore all of this :)

If you don't want to do this, and you only have to support specific browsers, you could also use the new getters to also return "uppercase(field)": see http://robertnyman.com/2009/05/28/getters-and-setters-with-javascript-code-samples-and-demos/ and the links on that page for more information.

EDIT:

Incredibly, this is also almost twice as fast, at least on my FF3.5 at work. See: http://jsperf.com/spiny001

How to return a specific element of an array?

You code should look like this:

public int getElement(int[] arrayOfInts, int index) {
    return arrayOfInts[index];
}

Main points here are method return type, it should match with array elements type and if you are working from main() - this method must be static also.

Makefile, header dependencies

How about something like:

includes = $(wildcard include/*.h)

%.o: %.c ${includes}
    gcc -Wall -Iinclude ...

You could also use the wildcards directly, but I tend to find I need them in more than one place.

Note that this only works well on small projects, since it assumes that every object file depends on every header file.

IF-THEN-ELSE statements in postgresql

case when field1>0 then field2/field1 else 0 end as field3

Download a file from HTTPS using download.file()

Try following with heavy files

library(data.table)
URL <- "http://d396qusza40orc.cloudfront.net/getdata%2Fdata%2Fss06hid.csv"
x <- fread(URL)

Failed to find target with hash string 'android-25'

I got similar problem

1: I tried to resolve with the answer which is marked correct above But I was not able to get the system setting which was quit amazing (On MacBook).

Most of the time such errors & issues comes because of replacing your grade file with other grade file ,due which gradel does not sync properly and while building the project issue comes . The issue is bascially related to non syncing for platform tools

Solution a: Go to File and then to Your project strucutre -modules -app-Properties -build tool version -click on options which is required for your project (if required build tool version not there chose any other). This will sync the grade file and now you can go to gradel and change target version and build tool version as per your requirement .you will prompted to download the required platform tool to sync it , now click on install tool version and let project to build

Solution b: Try Anuja Ans if you can get option of system setting and install platform tool.

Only on Firefox "Loading failed for the <script> with source"

If the src is https and the certificate has expired -- and even if you've made an exception -- firefox will still display this error message, and you can see the exact reason why if you look at the request under the network tab.

How to add Web API to an existing ASP.NET MVC 4 Web Application project?

As soon as you add a "WebApi Controller" under controllers folder, Visual Studio takes care of dependencies automatically;

Visual Studio has added the full set of dependencies for ASP.NET Web API 2 to project 'MyTestProject'.

The Global.asax.cs file in the project may require additional changes to enable ASP.NET Web API.

  1. Add the following namespace references:

    using System.Web.Http; using System.Web.Routing;

  2. If the code does not already define an Application_Start method, add the following method:

    protected void Application_Start() { }

  3. Add the following lines to the beginning of the Application_Start method:

    GlobalConfiguration.Configure(WebApiConfig.Register);

How to do something to each file in a directory with a batch script

Another way:

for %f in (*.mp4) do call ffmpeg -i "%~f" -vcodec copy -acodec copy "%~nf.avi"

How do I add an active class to a Link from React Router?

Expanding on @BaiJiFeiLong's answer, add an active={} property to the link:

<Nav.Link as={Link} to="/user" active={pathname.startsWith('/user')}>User</Nav.Link>

This will show the User link as active when any path starts with '/user'. For this to update with each path change, include withRouter() on the component:

import React from 'react'
import { Link, withRouter } from 'react-router-dom'
import Navbar from 'react-bootstrap/Navbar'
import Nav from 'react-bootstrap/Nav'

function Header(props) {
    const pathname = props.location.pathname

    return (
        <Navbar variant="dark" expand="sm" bg="black">
            <Navbar.Brand as={Link} to="/">
                Brand name
            </Navbar.Brand>
            <Navbar.Toggle aria-controls="basic-navbar-nav" />
            <Navbar.Collapse id="basic-navbar-nav">
                <Nav className="mr-auto">
                    <Nav.Link as={Link} to="/user" active={pathname.startsWith('/user')}>User</Nav.Link>
                    <Nav.Link as={Link} to="/about" active={pathname.startsWith('/about')}>About</Nav.Link>
                </Nav>
            </Navbar.Collapse>
        </Navbar>
    )
}

export default withRouter(Header)   // updates on every new page

How to convert the background to transparent?

If you want a command-line solution, you can use the ImageMagick convert utility:

convert input.png -transparent red output.png

How do I wait for a promise to finish before returning the variable of a function?

You're not actually using promises here. Parse lets you use callbacks or promises; your choice.

To use promises, do the following:

query.find().then(function() {
    console.log("success!");
}, function() {
    console.log("error");
});

Now, to execute stuff after the promise is complete, you can just execute it inside the promise callback inside the then() call. So far this would be exactly the same as regular callbacks.

To actually make good use of promises is when you chain them, like this:

query.find().then(function() {
    console.log("success!");

    return new Parse.Query(Obj).get("sOmE_oBjEcT");
}, function() {
    console.log("error");
}).then(function() {
    console.log("success on second callback!");
}, function() {
    console.log("error on second callback");
});

#include errors detected in vscode

1.Install Mingw-w64

2.Then Edit environment variables for your account "C:\mingw-w64\x86_64-8.1.0-win32-seh-rt_v6-rev0\mingw64\bin"

3.Reload

  • For MAC

    1.Open search ,command + shift +P, and run this code “c/c++ edit configurations (ui)”

    2.open file c_cpp_properties.json and update the includePath from "${workspaceFolder}/**" to "${workspaceFolder}/inc"

Append text to textarea with javascript

Use event delegation by assigning the onclick to the <ol>. Then pass the event object as the argument, and using that, grab the text from the clicked element.

_x000D_
_x000D_
function addText(event) {_x000D_
    var targ = event.target || event.srcElement;_x000D_
    document.getElementById("alltext").value += targ.textContent || targ.innerText;_x000D_
}
_x000D_
<textarea id="alltext"></textarea>_x000D_
_x000D_
<ol onclick="addText(event)">_x000D_
  <li>Hello</li>_x000D_
  <li>World</li>_x000D_
  <li>Earthlings</li>_x000D_
</ol>
_x000D_
_x000D_
_x000D_

Note that this method of passing the event object works in older IE as well as W3 compliant systems.

How to use <sec:authorize access="hasRole('ROLES)"> for checking multiple Roles?

There is a special security expression in spring security:

hasAnyRole(list of roles) - true if the user has been granted any of the roles specified (given as a comma-separated list of strings).

I have never used it but I think it is exactly what you are looking for.

Example usage:

<security:authorize access="hasAnyRole('ADMIN', 'DEVELOPER')">
    ...
</security:authorize>

Here is a link to the reference documentation where the standard spring security expressions are described. Also, here is a discussion where I described how to create custom expression if you need it.

Laravel: How to Get Current Route Name? (v5 ... v7)

Try this

Route::getCurrentRoute()->getPath();

or

\Request::route()->getName()

from v5.1

use Illuminate\Support\Facades\Route;
$currentPath= Route::getFacadeRoot()->current()->uri();

Laravel v5.2

Route::currentRouteName(); //use Illuminate\Support\Facades\Route;

Or if you need the action name

Route::getCurrentRoute()->getActionName();

Laravel 5.2 route documentation

Retrieving The Request URI

The path method returns the request's URI. So, if the incoming request is targeted at http://example.com/foo/bar, the path method will return foo/bar:

$uri = $request->path();

The is method allows you to verify that the incoming request URI matches a given pattern. You may use the * character as a wildcard when utilizing this method:

if ($request->is('admin/*')) {
    //
}

To get the full URL, not just the path info, you may use the url method on the request instance:

$url = $request->url();

Laravel v5.3 ... v5.8

$route = Route::current();

$name = Route::currentRouteName();

$action = Route::currentRouteAction();

Laravel 5.3 route documentation

Laravel v6.x...7.x

$route = Route::current();

$name = Route::currentRouteName();

$action = Route::currentRouteAction();

** Current as of Nov 11th 2019 - version 6.5 **

Laravel 6.x route documentation

There is an option to use request to get route

$request->route()->getName();

Can I force a page break in HTML printing?

Just wanted to put an update. page-break-after is a legacy property now.

Official page states

This property has been replaced by the break-after property.

How to set the height and the width of a textfield in Java?

set the height to 200

Set the Font to a large variant (150+ px). As already mentioned, control the width using columns, and use a layout manager (or constraint) that will respect the preferred width & height.

Big Text Fields

import java.awt.*;
import javax.swing.*;
import javax.swing.border.EmptyBorder;

public class BigTextField {

    public static void main(String[] args) {
        Runnable r = new Runnable() {

            @Override
            public void run() {
                // the GUI as seen by the user (without frame)
                JPanel gui = new JPanel(new FlowLayout(5));
                gui.setBorder(new EmptyBorder(2, 3, 2, 3));

                // Create big text fields & add them to the GUI
                String s = "Hello!";
                JTextField tf1 = new JTextField(s, 1);
                Font bigFont = tf1.getFont().deriveFont(Font.PLAIN, 150f);
                tf1.setFont(bigFont);
                gui.add(tf1);

                JTextField tf2 = new JTextField(s, 2);
                tf2.setFont(bigFont);
                gui.add(tf2);

                JTextField tf3 = new JTextField(s, 3);
                tf3.setFont(bigFont);
                gui.add(tf3);

                gui.setBackground(Color.WHITE);

                JFrame f = new JFrame("Big Text Fields");
                f.add(gui);
                // Ensures JVM closes after frame(s) closed and
                // all non-daemon threads are finished
                f.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
                // See http://stackoverflow.com/a/7143398/418556 for demo.
                f.setLocationByPlatform(true);

                // ensures the frame is the minimum size it needs to be
                // in order display the components within it
                f.pack();
                // should be done last, to avoid flickering, moving,
                // resizing artifacts.
                f.setVisible(true);
            }
        };
        // Swing GUIs should be created and updated on the EDT
        // http://docs.oracle.com/javase/tutorial/uiswing/concurrency/initial.html
        SwingUtilities.invokeLater(r);
    }
}

Is it possible to clone html element objects in JavaScript / JQuery?

Try this:

$('#foo1').html($('#foo2').children().clone());

How to add two edit text fields in an alert dialog

Check this code in alert box have edit textview when click OK it displays on screen using toast.

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    final AlertDialog.Builder alert = new AlertDialog.Builder(this);
    final EditText input = new EditText(this);
    alert.setView(input);
    alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int whichButton) {
            String value = input.getText().toString().trim();
            Toast.makeText(getApplicationContext(), value, 
                Toast.LENGTH_SHORT).show();
        }
    });

    alert.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
        public void onClick(DialogInterface dialog, int whichButton) {
            dialog.cancel();
        }
    });
    alert.show();               
}

vertical alignment of text element in SVG

The alignment-baseline property is what you're looking for it can take the following values

auto | baseline | before-edge | text-before-edge | 
middle | central | after-edge | text-after-edge | 
ideographic | alphabetic | hanging | mathematical | 
inherit

Description from w3c

This property specifies how an object is aligned with respect to its parent. This property specifies which baseline of this element is to be aligned with the corresponding baseline of the parent. For example, this allows alphabetic baselines in Roman text to stay aligned across font size changes. It defaults to the baseline with the same name as the computed value of the alignment-baseline property. That is, the position of "ideographic" alignment-point in the block-progression-direction is the position of the "ideographic" baseline in the baseline-table of the object being aligned.

W3C Source

Unfortunately, although this is the "correct" way of achieving what you're after it would appear Firefox have not implemented a lot of the presentation attributes for the SVG Text Module ('SVG in Firefox' MDN Documentation)

Pressing Ctrl + A in Selenium WebDriver

By using the Robot class in Java:

import java.awt.Robot;
import java.awt.event.KeyEvent;

public class Test1
{
    public static void main(String[] args) throws Exception
    {
        WebDriver d1 = new FirefoxDriver();
        d1.navigate().to("https://www.youtube.com/");
        Thread.sleep(3000);
        Robot rb = new Robot();
        rb.keyPress(KeyEvent.VK_TAB);
        rb.keyRelease(KeyEvent.VK_TAB);
        rb.keyPress(KeyEvent.VK_TAB);
        rb.keyRelease(KeyEvent.VK_TAB);

        // Perform [Ctrl+A] Operation - it works
        rb.keyPress(KeyEvent.VK_CONTROL);
        rb.keyPress(KeyEvent.VK_A);

        // It needs to release key after pressing
        rb.keyRelease(KeyEvent.VK_A);
        rb.keyRelease(KeyEvent.VK_CONTROL);
        Thread.sleep(3000);
    }
}

How can I modify a saved Microsoft Access 2007 or 2010 Import Specification?

When I want to examine or change an import / export specification I query the tables in MS Access where the specification is defined.

SELECT 
    MSysIMEXSpecs.SpecName,
    MSysIMexColumns.*
FROM 
    MSysIMEXSpecs
    LEFT JOIN MSysIMEXColumns 
    ON MSysIMEXSpecs.SpecID = MSysIMEXColumns.SpecID
WHERE
    SpecName = 'MySpecName'
ORDER BY
    MSysIMEXSpecs.SpecID, MSysIMEXColumns.Start;

You can also use an UPDATE or INSERT statement to alter existing columns or insert and append new columns to an existing specification. You can create entirely new specifications using this methodology.