Programs & Examples On #Jtag

JTAG is a common interface used for programming and debugging microprocessors and other types of embedded devices.

How to set the custom border color of UIView programmatically?

You can write an extension to use it with all the UIViews eg. UIButton, UILabel, UIImageView etc. You can customise my following method as per your requirement, but I think it will work well for you.

extension UIView{

    func setBorder(radius:CGFloat, color:UIColor = UIColor.clearColor()) -> UIView{
        var roundView:UIView = self
        roundView.layer.cornerRadius = CGFloat(radius)
        roundView.layer.borderWidth = 1
        roundView.layer.borderColor = color.CGColor
        roundView.clipsToBounds = true
        return roundView


btnLogin.setBorder(7, color: UIColor.lightGrayColor())

Call method when home button pressed

The Home button is a very dangerous button to override and, because of that, Android will not let you override its behavior the same way you do the BACK button.

Take a look at this discussion.

You will notice that the home button seems to be implemented as a intent invocation, so you'll end up having to add an intent category to your activity. Then, any time the user hits home, your app will show up as an option. You should consider what it is you are looking to accomplish with the home button. If its not to replace the default home screen of the device, I would be wary of overloading the HOME button, but it is possible (per discussion in above thread.)

Junit - run set up method once

Try this solution: :

with @BeforeAllMethods/@AfterAllMethods annotation you could execute any method in Test class in an instance context, where all injected values are available.

jQuery get values of checked checkboxes into array

I refactored your code a bit and believe I came with the solution for which you were looking. Basically instead of setting searchIDs to be the result of the .map() I just pushed the values into an array.


  var searchIDs = [];

  $("#find-table input:checkbox:checked").map(function(){


I created a fiddle with the code running.

How to put labels over geom_bar in R with ggplot2

As with many tasks in ggplot, the general strategy is to put what you'd like to add to the plot into a data frame in a way such that the variables match up with the variables and aesthetics in your plot. So for example, you'd create a new data frame like this:

dfTab <-
colnames(dfTab)[1] <- "x"
dfTab$lab <- as.character(100 * dfTab$Freq / sum(dfTab$Freq))

So that the x variable matches the corresponding variable in df, and so on. Then you simply include it using geom_text:

ggplot(df) + geom_bar(aes(x,fill=x)) + 
    geom_text(data=dfTab,aes(x=x,y=Freq,label=lab),vjust=0) +

This example will plot just the percentages, but you can paste together the counts as well via something like this:

dfTab$lab <- paste(dfTab$Freq,paste("(",dfTab$lab,"%)",sep=""),sep=" ")

Note that in the current version of ggplot2, opts is deprecated, so we would use theme and element_blank now.

HTML embed autoplay="false", but still plays automatically

Just change the mime type to: type="audio/mpeg", this way chrome will honor the autostart="false" parameter.

Getting CheckBoxList Item values

Instead of this:


Try This:


It worked for me :)

How to Set Focus on JTextField?

How about put jTextField.requestFocusInWindow(); into jTextField FocusLost event? Works for me have 5 controls on JPanel Soon as click on MessageBox, focus lost on jTextField. Used all the suggested codes but no luck Only above method works my case.

Authenticate with GitHub using a token

By having struggling so many hours on applying GitHub token finally it works as below:

$ cf_export GITHUB_TOKEN=$(codefresh get context github --decrypt -o yaml | yq -y

  • code follows Codefresh guidance on cloning a repo using token (freestyle}
  • test carried: sed %d%H%M on match word '-123456-whatever'
  • push back to the repo (which is private repo)
  • triggered by DockerHub webhooks

Following is the complete code:

version: '1.0'
    title: Reading Github token
    image: codefresh/cli
      - cf_export GITHUB_TOKEN=$(codefresh get context github --decrypt -o yaml | yq -y
    title: Updating the repo
    image: alpine/git:latest
      - git clone https://chetabahana:[email protected]/chetabahana/compose.git
      - cd compose && git remote rm origin
      - git config --global "chetabahana"
      - git config --global "[email protected]"
      - git remote add origin https://chetabahana:[email protected]/chetabahana/compose.git
      - sed -i "s/-[0-9]\{1,\}-\([a-zA-Z0-9_]*\)'/-`date +%d%H%M`-whatever'/g" cloudbuild.yaml
      - git status && git add . && git commit -m "fresh commit" && git push -u origin master


On branch master 
Changes not staged for commit: 
  (use "git add ..." to update what will be committed) 
  (use "git checkout -- ..." to discard changes in working directory) 

modified:   cloudbuild.yaml 

no changes added to commit (use "git add" and/or "git commit -a") 
[master dbab20f] fresh commit 
 1 file changed, 1 insertion(+), 1 deletion(-) 
Enumerating objects: 5, done. 
Counting objects:  20% (1/5) ...  Counting objects: 100% (5/5), done. 
Delta compression using up to 4 threads 
Compressing objects:  33% (1/3) ... Writing objects: 100% (3/3), 283 bytes | 283.00 KiB/s, done. 
Total 3 (delta 2), reused 0 (delta 0) 
remote: Resolving deltas:   0% (0/2)  ...   (2/2), completed with 2 local objects. 
   bbb6d2f..dbab20f  master -> master 
Branch 'master' set up to track remote branch 'master' from 'origin'. 
Reading environment variable exporting file contents. 
Successfully ran freestyle step: Cloning the repo 

How do I fill arrays in Java?

Arrays.fill(). The method is overloaded for different data types, and there is even a variation that fills only a specified range of indices.

jquery $(this).id return Undefined

Another option (just so you've seen it):

$(function () {
    $(".inputs").click(function (e) {


String to char array Java

A string to char array is as simple as

String str = "someString"; 
char[] charArray = str.toCharArray();

Can you explain a little more on what you are trying to do?

* Update *

if I am understanding your new comment, you can use a byte array and example is provided.

byte[] bytes = ByteBuffer.allocate(4).putInt(1695609641).array();

for (byte b : bytes) {
   System.out.format("0x%x ", b);

With the following output

0x65 0x10 0xf3 0x29

How to set Sqlite3 to be case insensitive when string comparing?

Another option that may or may not make sense in your case, is to actually have a separate column with pre-lowerscored values of your existing column. This can be populated using the SQLite function LOWER(), and you can then perform matching on this column instead.

Obviously, it adds redundancy and a potential for inconsistency, but if your data is static it might be a suitable option.

How to do URL decoding in Java?

Using class:

public String getDecodedURL(String encodedUrl) {
    try {
        URI uri = new URI(encodedUrl);
        return uri.getScheme() + ":" + uri.getSchemeSpecificPart();
    } catch (Exception e) {
        return "";

Please note that exception handling can be better, but it's not much relevant for this example.

Finishing current activity from a fragment

try to use this

yes Fragment.class does not implement finish()

When working with fragments, instead of using this or refering to the context, always use getActivity(). You should call

Return rows in random order

SQL Server / MS Access Syntax:


MySQL Syntax:


Google Play Services GCM 9.2.0 asks to "update" back to 9.0.0

Just put this line at the bottom of your app-module's (not project root's) gradle file.

apply plugin: ''

Then rebuild your project.

Use Font Awesome icon as CSS content

a:before {
     content: "\f055";
     font-family: FontAwesome;

Example Link:

Get Icon code from:

CURL Command Line URL Parameters

Felipsmartins is correct.

It is worth mentioning that it is because you cannot really use the -d/--data option if this is not a POST request. But this is still possible if you use the -G option.

Which means you can do this:

curl -X DELETE -G 'http://localhost:5000/locations' -d 'id=3'

Here it is a bit silly but when you are on the command line and you have a lot of parameters, it is a lot tidier.

I am saying this because cURL commands are usually quite long, so it is worth making it on more than one line escaping the line breaks.

curl -X DELETE -G \
'http://localhost:5000/locations' \
-d id=3 \
-d name=Mario \
-d surname=Bros

This is obviously a lot more comfortable if you use zsh. I mean when you need to re-edit the previous command because zsh lets you go line by line. (just saying)

Hope it helps.

Why is HttpContext.Current null?

Clearly HttpContext.Current is not null only if you access it in a thread that handles incoming requests. That's why it works "when i use this code in another class of a page".

It won't work in the scheduling related class because relevant code is not executed on a valid thread, but a background thread, which has no HTTP context associated with.

Overall, don't use Application["Setting"] to store global stuffs, as they are not global as you discovered.

If you need to pass certain information down to business logic layer, pass as arguments to the related methods. Don't let your business logic layer access things like HttpContext or Application["Settings"], as that violates the principles of isolation and decoupling.

Update: Due to the introduction of async/await it is more often that such issues happen, so you might consider the following tip,

In general, you should only call HttpContext.Current in only a few scenarios (within an HTTP module for example). In all other cases, you should use

instead of HttpContext.Current.

Batch Extract path and filename from a variable

set file=C:\Users\l72rugschiri\Desktop\fs.cfg
FOR %%i IN ("%file%") DO (
ECHO filedrive=%%~di
ECHO filepath=%%~pi
ECHO filename=%%~ni
ECHO fileextension=%%~xi

Not really sure what you mean by no "function"

Obviously, change ECHO to SET to set the variables rather thon ECHOing them...

See for documentation for a full list.

ceztko's test case (for reference)

set file="C:\Users\ l72rugschiri\Desktop\fs.cfg"
FOR /F "delims=" %%i IN ("%file%") DO (
ECHO filedrive=%%~di
ECHO filepath=%%~pi
ECHO filename=%%~ni
ECHO fileextension=%%~xi

Comment : please see comments.

How can I make SQL case sensitive string comparison on MySQL?


I share with you, code from a function that compares passwords:

SET pSignal =
(SELECT DECODE(r.usignal,'YOURSTRINGKEY') FROM rsw_uds r WHERE r.uname =
in_usdname AND r.uvige = 1);

SET pSuccess =(SELECT in_usdsignal LIKE BINARY pSignal);

IF pSuccess = 1 THEN
      /*Your code if match*/
      /*Your code if don't match*/


Using JQuery to open a popup window and print

You should put the print function in your view-details.php file and call it once the file is loaded, by either using

<body onload="window.print()"> 


$(document).ready(function () { 

Python function global variables?

If you want to simply access a global variable you just use its name. However to change its value you need to use the global keyword.


global someVar
someVar = 55

This would change the value of the global variable to 55. Otherwise it would just assign 55 to a local variable.

The order of function definition listings doesn't matter (assuming they don't refer to each other in some way), the order they are called does.

How to put a link on a button with bootstrap?

Combining the above answers i find a simply solution that probably will help you too:

<button type="submit" onclick="location.href = 'your_link';">Login</button>

by just adding inline JS code you can transform a button in a link and keeping his design.

How to print (using cout) a number in binary form?

In C++20 you'll be able to use std::format to do this:

unsigned char a = -58;
std::cout << std::format("{:b}", a);



In the meantime you can use the {fmt} library, std::format is based on. {fmt} also provides the print function that makes this even easier and more efficient (godbolt):

unsigned char a = -58;
fmt::print("{:b}", a);

Disclaimer: I'm the author of {fmt} and C++20 std::format.

Converting any string into camel case

I just ended up doing this:

String.prototype.toCamelCase = function(str) {
    return str
        .replace(/\s(.)/g, function($1) { return $1.toUpperCase(); })
        .replace(/\s/g, '')
        .replace(/^(.)/, function($1) { return $1.toLowerCase(); });

I was trying to avoid chaining together multiple replace statements. Something where I'd have $1, $2, $3 in my function. But that type of grouping is hard to understand, and your mention about cross browser problems is something I never thought about as well.

How to enable multidexing with the new Android Multidex support library


multiDexEnabled true
implementation 'androidx.multidex:multidex:2.0.1'



what is trailing whitespace and how can I handle this?

This is just a warning and it doesn't make problem for your project to run, you can just ignore it and continue coding. But if you're obsessed about clean coding, same as me, you have two options:

  1. Hover the mouse on warning in VS Code or any IDE and use quick fix to remove white spaces.
  2. Press f1 then type trim trailing whitespace.

How to monitor SQL Server table changes by using c#?

Generally, you'd use Service Broker

That is trigger -> queue -> application(s)

Edit, after seeing other answers:

FYI: "Query Notifications" is built on Service broker


More links

Reading Datetime value From Excel sheet

Or you can simply use OleDbDataAdapter to get data from Excel

How can I plot separate Pandas DataFrames as subplots?

You can use the familiar Matplotlib style calling a figure and subplot, but you simply need to specify the current axis using plt.gca(). An example:

df.A.plot() #no need to specify for first axis


Pandas: Appending a row to a dataframe and specify its index label

There is another solution. The next code is bad (although I think pandas needs this feature):

import pandas as pd

# empty dataframe
a = pd.DataFrame()
a.loc[0] = {'first': 111, 'second': 222}

But the next code runs fine:

import pandas as pd

# empty dataframe
a = pd.DataFrame()
a = a.append(pd.Series({'first': 111, 'second': 222}, name=0))

How to pad a string to a fixed length with spaces in Python?

You can use the ljust method on strings.

>>> name = 'John'
>>> name.ljust(15)
'John           '

Note that if the name is longer than 15 characters, ljust won't truncate it. If you want to end up with exactly 15 characters, you can slice the resulting string:

>>> name.ljust(15)[:15]

Sending Windows key using SendKeys

Alt+F4 is working only in brackets


How to create EditText with cross(x) button at end of it?

Here is the simple complete solution in kotlin.

This whole layout will be your search bar


            android:paddingEnd="10dp" />



Now this is the functionality of clear button, paste this code in onCreate method.

search_et.addTextChangedListener(object: TextWatcher {
            override fun beforeTextChanged(s:CharSequence, start:Int, count:Int, after:Int) {
            override fun onTextChanged(s:CharSequence, start:Int, before:Int, count:Int) {
            override fun afterTextChanged(s: Editable) {
                if (s.isNotEmpty()){
                    clear_btn.visibility = VISIBLE
                    clear_btn.setOnClickListener {
                    clear_btn.visibility = GONE

What is HTTP "Host" header?

The Host Header tells the webserver which virtual host to use (if set up). You can even have the same virtual host using several aliases (= domains and wildcard-domains). In this case, you still have the possibility to read that header manually in your web app if you want to provide different behavior based on different domains addressed. This is possible because in your webserver you can (and if I'm not mistaken you must) set up one vhost to be the default host. This default vhost is used whenever the host header does not match any of the configured virtual hosts.

That means: You get it right, although saying "multiple hosts" may be somewhat misleading: The host (the addressed machine) is the same, what really gets resolved to the IP address are different domain names (including subdomains) that are also referred to as hostnames (but not hosts!).

Although not part of the question, a fun fact: This specification led to problems with SSL in early days because the web server has to deliver the certificate that corresponds to the domain the client has addressed. However, in order to know what certificate to use, the webserver should have known the addressed hostname in advance. But because the client sends that information only over the encrypted channel (which means: after the certificate has already been sent), the server had to assume you browsed the default host. That meant one ssl-secured domain per IP address / port-combination.

This has been overcome with Server Name Indication; however, that again breaks some privacy, as the server name is now transferred in plain text again, so every man-in-the-middle would see which hostname you are trying to connect to.

Although the webserver would know the hostname from Server Name Indication, the Host header is not obsolete, because the Server Name Indication information is only used within the TLS handshake. With an unsecured connection, there is no Server Name Indication at all, so the Host header is still valid (and necessary).

Another fun fact: Most webservers (if not all) reject your HTTP request if it does not contain exactly one Host header, even if it could be omitted because there is only the default vhost configured. That means the minimum required information in an http-(get-)request is the first line containing METHOD RESOURCE and PROTOCOL VERSION and at least the Host header, like this:

GET /someresource.html HTTP/1.1

In the MDN Documentation on the "Host" header they actually phrase it like this:

A Host header field must be sent in all HTTP/1.1 request messages. A 400 (Bad Request) status code will be sent to any HTTP/1.1 request message that lacks a Host header field or contains more than one.

As mentioned by Darrel Miller, the complete specs can be found in RFC7230.

How to check sbt version?

From within the sbt shell

sbt:venkat> about
[info] This is sbt 1.3.3

Psql could not connect to server: No such file or directory, 5432 error?

Open your database manager and execute this script

update pg_database set datallowconn = 'true' where datname = 'your_database_name';

Sort ObservableCollection<string> through C#

This is an ObservableCollection<T>, that automatically sorts itself upon a change, triggers a sort only when necessary, and only triggers a single move collection change action.

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Linq;

namespace ConsoleApp4
  using static Console;

  public class SortableObservableCollection<T> : ObservableCollection<T>
    public Func<T, object> SortingSelector { get; set; }
    public bool Descending { get; set; }
    protected override void OnCollectionChanged(NotifyCollectionChangedEventArgs e)
      if (SortingSelector == null 
          || e.Action == NotifyCollectionChangedAction.Remove
          || e.Action == NotifyCollectionChangedAction.Reset)

      var query = this
        .Select((item, index) => (Item: item, Index: index));
      query = Descending
        ? query.OrderBy(tuple => SortingSelector(tuple.Item))
        : query.OrderByDescending(tuple => SortingSelector(tuple.Item));

      var map = query.Select((tuple, index) => (OldIndex:tuple.Index, NewIndex:index))
       .Where(o => o.OldIndex != o.NewIndex);

      using (var enumerator = map.GetEnumerator())
       if (enumerator.MoveNext())
          Move(enumerator.Current.OldIndex, enumerator.Current.NewIndex);


  class Program
    static void Main(string[] args)
      var xx = new SortableObservableCollection<int>() { SortingSelector = i => i };
      xx.CollectionChanged += (sender, e) =>
       WriteLine($"action: {e.Action}, oldIndex:{e.OldStartingIndex},"
         + " newIndex:{e.NewStartingIndex}, newValue: {xx[e.NewStartingIndex]}");


      foreach (var item in xx)
        Write($"{item}, ");


action: Add, oldIndex:-1, newIndex:0, newValue: 10
action: Add, oldIndex:-1, newIndex:1, newValue: 8
action: Move, oldIndex:1, newIndex:0, newValue: 8
action: Add, oldIndex:-1, newIndex:2, newValue: 45
action: Add, oldIndex:-1, newIndex:3, newValue: 0
action: Move, oldIndex:3, newIndex:0, newValue: 0
action: Add, oldIndex:-1, newIndex:4, newValue: 100
action: Add, oldIndex:-1, newIndex:5, newValue: -800
action: Move, oldIndex:5, newIndex:0, newValue: -800
action: Add, oldIndex:-1, newIndex:6, newValue: 4857
action: Add, oldIndex:-1, newIndex:7, newValue: -1
action: Move, oldIndex:7, newIndex:1, newValue: -1
-800, -1, 0, 8, 10, 45, 100, 4857,

Internet Explorer cache location

I don't know the answer for XP, but for latter:

%USERPROFILE%\AppData\Local\Microsoft\Windows\Temporary Internet Files\Low and %USERPROFILE%\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.IE5 - these are cache locations. Other mentioned %USERPROFILE%\AppData\Local\Microsoft\Windows\Temporary Internet Files but this not a cache in this directory there are just a reflection of files that are stored somewhere else.

But you can enum %USERPROFILE%\AppData\Local\Microsoft\Windows\Temporary Internet Files and get all files you need, but you should be frustrated that file walker do not detect everything that explorer shows.

Also if you use links I gave you may need ExpandEnvironmentStrings from WinAPI.

How do I check which version of NumPy I'm using?

From the command line, you can simply issue:

python -c "import numpy; print(numpy.version.version)"


python -c "import numpy; print(numpy.__version__)"

Difference between framework vs Library vs IDE vs API vs SDK vs Toolkits?

Consider Android Development:

IDE: Eclipse etc..

Library: library (Class with all code)

API: Interface basically all functions with which we call

SDK: The Android SDK provides you the API libraries and developer tools necessary to build, test, and debug apps for Android (----tools - DDMS,Emulator ----platforms - Android OS versions, ----platform-tools - ADB, ----API docs)

ToolKit: Could be ADT Bundle

Framework: Big library but more of architecture-oriented

Convert Datetime column from UTC to local time in select statement

Using new SQL Server 2016 opportunities:

CREATE FUNCTION ToLocalTime(@dtUtc datetime, @timezoneId nvarchar(256))
RETURNS datetime

return @dtUtc AT TIME ZONE 'UTC' AT TIME ZONE @timezoneId

/* -- second way, faster

return SWITCHOFFSET(@dtUtc , DATENAME(tz, @dtUtc AT TIME ZONE @timezoneId))


/* -- third way

declare @dtLocal datetimeoffset
set @dtLocal = @dtUtc AT TIME ZONE @timezoneId
return dateadd(minute, DATEPART (TZoffset, @dtLocal), @dtUtc)



But clr procedure works in 5 times faster :'-(

Pay attention that Offset for one TimeZone can change to winter or summer time. For example

select cast('2017-02-08 09:00:00.000' as datetime) AT TIME ZONE 'Eastern Standard Time'
select cast('2017-08-08 09:00:00.000' as datetime) AT TIME ZONE 'Eastern Standard Time'


2017-02-08 09:00:00.000 -05:00
2017-08-08 09:00:00.000 -04:00

You can't just add constant offset.

iOS Launching Settings -> Restrictions URL Scheme

I wanted to open the Bluetooth Menu in the Settings Application and the above path (prefs:root=General&path=Bluetooth) didn't work for me. What ended up working for me was


Make sure you have the prefs URL Scheme defined first.

Calculating the position of points in a circle

Using one of the above answers as a base, here's the Java/Android example:

protected void onDraw(Canvas canvas) {

    RectF bounds = new RectF(canvas.getClipBounds());
    float centerX = bounds.centerX();
    float centerY = bounds.centerY();

    float angleDeg = 90f;
    float radius = 20f

    float xPos = radius * (float)Math.cos(Math.toRadians(angleDeg)) + centerX;
    float yPos = radius * (float)Math.sin(Math.toRadians(angleDeg)) + centerY;

    //draw my point at xPos/yPos

Find integer index of rows with NaN in pandas dataframe

Here are tests for a few methods:

%timeit np.where(np.isnan(df['b']))[0]
%timeit pd.isnull(df['b']).nonzero()[0]
%timeit np.where(df['b'].isna())[0]
%timeit df.loc[pd.isna(df['b']), :].index

And their corresponding timings:

333 µs ± 9.95 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
280 µs ± 220 ns per loop (mean ± std. dev. of 7 runs, 1000 loops each)
313 µs ± 128 ns per loop (mean ± std. dev. of 7 runs, 1000 loops each)
6.84 ms ± 1.59 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)

It would appear that pd.isnull(df['DRGWeight']).nonzero()[0] wins the day in terms of timing, but that any of the top three methods have comparable performance.

How do I get git to default to ssh and not https for new repositories

  • GitHub

    git config --global url.ssh://[email protected]/.insteadOf
  • BitBucket

    git config --global url.ssh://[email protected]/.insteadOf

That tells git to always use SSH instead of HTTPS when connecting to GitHub/BitBucket, so you'll authenticate by certificate by default, instead of being prompted for a password.

Cannot connect to repo with TortoiseSVN

Try clearing the settings under "Saved Data" - refer to:

This worked for me with Windows 7.


How do you add an image?

Never mind -- I'm an idiot. I just needed <xsl:value-of select="/root/Image/node()"/>

Insert results of a stored procedure into a temporary table

Well, you do have to create a temp table, but it doesn't have to have the right schema....I've created a stored procedure that modifies an existing temp table so that it has the required columns with the right data type and order (dropping all existing columns, adding new columns):

create procedure #TempTableForSP(@tableId int, @procedureId int)  
    declare @tableName varchar(max) =  (select name  
                                        from tempdb.sys.tables 
                                        where object_id = @tableId
    declare @tsql nvarchar(max);    
    declare @tempId nvarchar(max) = newid();      
    set @tsql = '    
    declare @drop nvarchar(max) = (select  ''alter table tempdb.dbo.' + @tableName 
            +  ' drop column ''  + quotename( + '';''+ char(10)  
                                   from tempdb.sys.columns c   
                                   where c.object_id =  ' + 
                                         cast(@tableId as varchar(max)) + '  
                                   for xml path('''')  
    alter table tempdb.dbo.' + @tableName + ' add ' + QUOTENAME(@tempId) + ' int;
    exec sp_executeSQL @drop;    
    declare @add nvarchar(max) = (    
                                select ''alter table ' + @tableName 
                                      + ' add '' + name 
                                      + '' '' + system_type_name 
                           + case when d.is_nullable=1 then '' null '' else '''' end 
                                      + char(10)   
                              from sys.dm_exec_describe_first_result_set_for_object(' 
                               + cast(@procedureId as varchar(max)) + ', 0) d  
                                order by column_ordinal  
                                for xml path(''''))    

    execute sp_executeSQL  @add;    
    alter table '  + @tableName + ' drop column ' + quotename(@tempId) + '  ';      
    execute sp_executeSQL @tsql;  

create table #exampleTable (pk int);

declare @tableId int = object_Id('tempdb..#exampleTable')
declare @procedureId int = object_id('examplestoredProcedure')

exec #TempTableForSP @tableId, @procedureId;

insert into #exampleTable
exec examplestoredProcedure

Note this won't work if sys.dm_exec_describe_first_result_set_for_object can't determine the results of the stored procedure (for instance if it uses a temp table).

Is it possible to display inline images from html in an Android TextView?

You could also write your own parser to pull the URL of all the images and then dynamically create new imageviews and pass in the urls.

php resize image on upload

// This was my example that I used to automatically resize every inserted photo to 100 by 50 pixel and image format to jpeg hope this helps too

$maxDimW = 100;
$maxDimH = 50;
list($width, $height, $type, $attr) = getimagesize( $_FILES['photo']['tmp_name'] );
if ( $width > $maxDimW || $height > $maxDimH ) {
    $target_filename = $_FILES['photo']['tmp_name'];
    $fn = $_FILES['photo']['tmp_name'];
    $size = getimagesize( $fn );
    $ratio = $size[0]/$size[1]; // width/height
    if( $ratio > 1) {
        $width = $maxDimW;
        $height = $maxDimH/$ratio;
    } else {
        $width = $maxDimW*$ratio;
        $height = $maxDimH;
    $src = imagecreatefromstring(file_get_contents($fn));
    $dst = imagecreatetruecolor( $width, $height );
    imagecopyresampled($dst, $src, 0, 0, 0, 0, $width, $height, $size[0], $size[1] );

    imagejpeg($dst, $target_filename); // adjust format as needed



MVC 5 Access Claims Identity User Data

To further touch on Darin's answer, you can get to your specific claims by using the FindFirst method:

var identity = (ClaimsIdentity)User.Identity;
var role = identity.FindFirst(ClaimTypes.Role).Value;

Xcode - ld: library not found for -lPods

Delete all the corresponding files/folders of imported cocoapods source except podfile.

install cocoapod again.This should clear any redundant pull from the original source.

size of uint8, uint16 and uint32?

uint8, uint16, uint32, and uint64 are probably Microsoft-specific types.

As of the 1999 standard, C supports standard typedefs with similar meanings, defined in <stdint.h>: uint8_t, uint16_t, uint32_t, and uint64_t. I'll assume that the Microsoft-specific types are defined similarly. Microsoft does support <stdint.h>, at least as of Visual Studio 2010, but older code may use uint8 et al.

The predefined types char, short, int et al have sizes that vary from one C implementation to another. The C standard has certain minimum requirements (char is at least 8 bits, short and int are at least 16, long is at least 32, and each type in that list is at least as wide as the previous type), but permits some flexibility. For example, I've seen systems where int is 16, 32, or 64 bits.

char is almost always exactly 8 bits, but it's permitted to be wider. And plain char may be either signed or unsigned.

uint8_t is required to be an unsigned integer type that's exactly 8 bits wide. It's likely to be a typedef for unsigned char, though it might be a typedef for plain char if plain char happens to be unsigned. If there is no predefined 8-bit unsigned type, then uint8_t will not be defined at all.

Similarly, each uintN_t type is an unsigned type that's exactly N bits wide.

In addition, <stdint.h> defines corresponding signed intN_t types, as well as int_fastN_t and int_leastN_t types that are at least the specified width.

The [u]intN_t types are guaranteed to have no padding bits, so the size of each is exactly N bits. The signed intN_t types are required to use a 2's-complement representation.

Although uint32_t might be the same as unsigned int, for example, you shouldn't assume that. Use unsigned int when you need an unsigned integer type that's at least 16 bits wide, and that's the "natural" size for the current system. Use uint32_t when you need an unsigned integer type that's exactly 32 bits wide.

(And no, uint64 or uint64_t is not the same as double; double is a floating-point type.)

How to get current time with jQuery

Convert a Date object to an string, using one of Date.prototype's conversion getters, for example:

var d = new Date();
d+'';                  // "Sun Dec 08 2013 18:55:38 GMT+0100"
d.toDateString();      // "Sun Dec 08 2013"
d.toISOString();       // "2013-12-08T17:55:38.130Z"
d.toLocaleDateString() // "8/12/2013" on my system
d.toLocaleString()     // "8/12/2013 18.55.38" on my system
d.toUTCString()        // "Sun, 08 Dec 2013 17:55:38 GMT"

Or, if you want it more customized, see the list of Date.prototype's getter methods.

How to pass command line arguments to a rake task

Most of the methods described above did not work for me, maybe they are deprecated in the newer versions. The up-to-date guide can be found here:

a copy-and-paste ans from the guide is here:

task :task_name, [:arg_1] => [:pre_1, :pre_2] do |t, args|
  # You can use args from here

Invoke it like this

bin/rake "task_name[value 1]" # entire argument string should be quoted

How do shift operators work in Java?

Signed left shift Logically Simple if 1<<11 it will tends to 2048 and 2<<11 will give 4096

In java programming int a = 2 << 11;

// it will result in 4096

2<<11 = 2*(2^11) = 4096

XMLHttpRequest (Ajax) Error

So there might be a few things wrong here.

First start by reading how to use because there's a third optional parameter for specifying whether to make an asynchronous request, defaulting to true. That means you're making an asynchronous request and need to specify a callback function before you do the send(). Here's an example from MDN:

var oXHR = new XMLHttpRequest();"GET", "", true);

oXHR.onreadystatechange = function (oEvent) {
    if (oXHR.readyState === 4) {
        if (oXHR.status === 200) {
        } else {
           console.log("Error", oXHR.statusText);


Second, since you're getting a 101 error, you might use the wrong URL. So make sure that the URL you're making the request with is correct. Also, make sure that your server is capable of serving your quiz.xml file.

You'll probably have to debug by simplifying/narrowing down where the problem is. So I'd start by making an easy synchronous request so you don't have to worry about the callback function. So here's another example from MDN for making a synchronous request:

var request = new XMLHttpRequest();'GET', 'file:///home/user/file.json', false); 

if (request.status == 0)

Also, if you're just starting out with Javascript, you could refer to MDN for Javascript API documentation/examples/tutorials.

Difference between "while" loop and "do while" loop

The most important difference between while and do-while loop is that in do-while, the block of code is executed at least once, even though the condition given is false.

To put it in a different way :

  • While- your condition is at the begin of the loop block, and makes possible to never enter the loop.
  • In While loop, the condition is first tested and then the block of code is executed if the test result is true.

How to remove specific substrings from a set of strings in Python?

>>> x = 'Pear.good'
>>> y = x.replace('.good','')
>>> y
>>> x

.replace doesn't change the string, it returns a copy of the string with the replacement. You can't change the string directly because strings are immutable.

You need to take the return values from x.replace and put them in a new set.

In C#, should I use string.Empty or String.Empty or "" to intitialize a string?

I was just looking at some code and this question popped into my mind which I had read some time before. This is certainly a question of readability.

Consider the following C# code...

(customer == null) ? "" : customer.Name


(customer == null) ? string.empty : customer.Name

I personally find the latter less ambiguous and easier to read.

As pointed out by others the actual differences are negligible.

Error while trying to retrieve text for error ORA-01019

In my case, I just needed to install oracle 10g client on the server, becase there there was the 11g version.

Ps: I don't needed unistall nothing, I just install the 10g version and updated the tnsnames file (C:\oracle\product\10.2.0\client_1\NETWORK\ADMIN)

How do I get a file's last modified time in Perl?

You could use stat() or the File::Stat module.

perldoc -f stat

How to have multiple colors in a Windows batch file?

You can do multicolor outputs without any external programs.

@echo off
SETLOCAL EnableDelayedExpansion
for /F "tokens=1,2 delims=#" %%a in ('"prompt #$H#$E# & echo on & for %%b in (1) do rem"') do (
  set "DEL=%%a"
echo say the name of the colors, don't read

call :ColorText 0a "blue"
call :ColorText 0C "green"
call :ColorText 0b "red"
call :ColorText 19 "yellow"
call :ColorText 2F "black"
call :ColorText 4e "white"

goto :eof

echo off
<nul set /p ".=%DEL%" > "%~2"
findstr /v /a:%1 /R "^$" "%~2" nul
del "%~2" > nul 2>&1
goto :eof

It uses the color feature of the findstr command.

Findstr can be configured to output line numbers or filenames in a defined color.
So I first create a file with the text as filename, and the content is a single <backspace> character (ASCII 8).
Then I search all non empty lines in the file and in nul, so the filename will be output in the correct color appended with a colon, but the colon is immediatly removed by the <backspace>.

EDIT: One year later ... all characters are valid

@echo off
setlocal EnableDelayedExpansion
for /F "tokens=1,2 delims=#" %%a in ('"prompt #$H#$E# & echo on & for %%b in (1) do rem"') do (
  set "DEL=%%a"

rem Prepare a file "X" with only one dot
<nul > X set /p ".=."

call :color 1a "a"
call :color 1b "b"
call :color 1c "^!<>&| %%%%"*?"
exit /b

set "param=^%~2" !
set "param=!param:"=\"!"
findstr /p /A:%1 "." "!param!\..\X" nul
<nul set /p ".=%DEL%%DEL%%DEL%%DEL%%DEL%%DEL%%DEL%"
exit /b

This uses the rule for valid path/filenames.
If a \..\ is in the path the prefixed elemet will be removed completly and it's not necessary that this element contains only valid filename characters.

Is there any way to set environment variables in Visual Studio Code?

For more advanced Go language scenarios, you can load an environment file, like this:

  "version": "0.2.0",
  "configurations": [
      "name": "Launch",
      "type": "go",
      "request": "launch", 
      "mode": "debug",
      "remotePath": "",
      "port": 2345,
      "host": "",
      "program": "${workspaceFolder}",
      "envFile": "${workspaceFolder}/.env",
      "args": [], 
      "showLog": true

Place the .env file in your folder and add vars like this:



How to show another window from mainwindow in QT

  1. Implement a slot in your QMainWindow where you will open your new Window,
  2. Place a widget on your QMainWindow,
  3. Connect a signal from this widget to a slot from the QMainWindow (for example: if the widget is a QPushButton connect the signal click() to the QMainWindow custom slot you have created).

Code example:


// ...
include "newwindow.h"
// ...
public slots:
   void openNewWindow();
// ...
   NewWindow *mMyNewWindow;
// ...


// ...
      // ...
      connect(mMyButton, SIGNAL(click()), this, SLOT(openNewWindow()));
      // ...
// ...
void MainWindow::openNewWindow()
   mMyNewWindow = new NewWindow(); // Be sure to destroy your window somewhere
   // ...

This is an example on how display a custom new window. There are a lot of ways to do this.

HTML set image on browser tab

<link rel="SHORTCUT ICON" href="favicon.ico" type="image/x-icon" />
<link rel="ICON" href="favicon.ico" type="image/ico" />

Excellent tool for cross-browser favicon -

What is the difference between CloseableHttpClient and HttpClient in Apache HttpClient API?

Jon skeet said:

The documentation seems pretty clear to me: "Base implementation of HttpClient that also implements Closeable" - HttpClient is an interface; CloseableHttpClient is an abstract class, but because it implements AutoCloseable you can use it in a try-with-resources statement.

But then Jules asked:

@JonSkeet That much is clear, but how important is it to close HttpClient instances? If it's important, why is the close() method not part of the basic interface?

Answer for Jules

close need not be part of basic interface since underlying connection is released back to the connection manager automatically after every execute

To accommodate the try-with-resources statement. It is mandatory to implement Closeable. Hence included it in CloseableHttpClient.


close method in AbstractHttpClient which is extending CloseableHttpClient is deprecated, I was not able to find the source code for that.

How to move mouse cursor using C#?

First Add a Class called Win32.cs

public class Win32
    public static extern long SetCursorPos(int x, int y);

    public static extern bool ClientToScreen(IntPtr hWnd, ref POINT point);

    public struct POINT
        public int x;
        public int y;

        public POINT(int X, int Y)
            x = X;
            y = Y;

You can use it then like this:

Win32.POINT p = new Win32.POINT(xPos, yPos);

Win32.ClientToScreen(this.Handle, ref p);
Win32.SetCursorPos(p.x, p.y);

Show an image preview before upload

For background images, make sure to use url()

node.backgroundImage = 'url(' + + ')';

don't fail jenkins build if execute shell fails

Jenkins determines the success/failure of a step by the return value of the step. For the case of a shell, it should be the return of the last value. For both Windows CMD and (POSIX) Bash shells, you should be able to set the return value manually by using exit 0 as the last command.

Seeing if data is normally distributed in R


performing HTTP requests with cURL (using PROXY)

From man curl:

-x, --proxy <[protocol://][user:password@]proxyhost[:port]>

     Use the specified HTTP proxy. 
     If the port number is not specified, it is assumed at port 1080.

General way:

export http_proxy=http://your.proxy.server:port/

Then you can connect through proxy from (many) application.

And, as per comment below, for https:

export https_proxy=https://your.proxy.server:port/

Xcode iOS 8 Keyboard types not supported

Go to iOS Simulator-> Hardware-> Keyboard -> Uncheck the Connect Hardware Keyboard Option. This will fix the issue.

How do I convert a number to a numeric, comma-separated formatted string?

Not sure it works in tsql, but some platforms have to_char():

test=#select to_char(131213211653.78, '9,999,999,999,999.99');
test=# select to_char(131213211653.78, '9G999G999G999G999D99');
test=# select to_char(485, 'RN');

As the example suggests, the format's length needs to match that of the number for best results, so you might want to wrap it in a function (e.g. number_format()) if needed.

Converting to money works too, as point out by the other repliers.

test=# select substring(cast(cast(131213211653.78 as money) as varchar) from 2);

Hibernate show real SQL

Can I see (...) the real SQL

If you want to see the SQL sent directly to the database (that is formatted similar to your example), you'll have to use some kind of jdbc driver proxy like P6Spy (or log4jdbc).

Alternatively you can enable logging of the following categories (using a file here):

The first is equivalent to hibernate.show_sql=true, the second prints the bound parameters among other things.


Differences between Html.TextboxFor and Html.EditorFor in MVC and Razor

The Html.TextboxFor always creates a textbox (<input type="text" ...).

While the EditorFor looks at the type and meta information, and can render another control or a template you supply.

For example for DateTime properties you can create a template that uses the jQuery DatePicker.

Python using enumerate inside list comprehension

Just to be really clear, this has nothing to do with enumerate and everything to do with list comprehension syntax.

This list comprehension returns a list of tuples:

[(i,j) for i in range(3) for j in 'abc']

this a list of dicts:

[{i:j} for i in range(3) for j in 'abc']

a list of lists:

[[i,j] for i in range(3) for j in 'abc']

a syntax error:

[i,j for i in range(3) for j in 'abc']

Which is inconsistent (IMHO) and confusing with dictionary comprehensions syntax:

>>> {i:j for i,j in enumerate('abcdef')}
{0: 'a', 1: 'b', 2: 'c', 3: 'd', 4: 'e', 5: 'f'}

And a set of tuples:

>>> {(i,j) for i,j in enumerate('abcdef')}
set([(0, 'a'), (4, 'e'), (1, 'b'), (2, 'c'), (5, 'f'), (3, 'd')])

As Óscar López stated, you can just pass the enumerate tuple directly:

>>> [t for t in enumerate('abcdef') ] 
[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'd'), (4, 'e'), (5, 'f')]

Is there a way to cache GitHub credentials for pushing commits?

For Windows you can use the Git Credential Manager (GCM) plugin. It is currently maintained by Microsoft. The nice thing is that it saves the password in the Windows Credential Store, not as plain text.

There is an installer on the releases page of the project. This will also install the official version of Git for Windows with the credential manager built-in. It allows two-factor authentication for GitHub (and other servers). And has a graphical interface for initially logging in.

For Cygwin users (or users already using the official Git for Windows), you might prefer the manual install. Download the zip package from the releases page. Extract the package, and then run the install.cmd file. This will install to your ~/bin folder. (Be sure your ~/bin directory is in your PATH.) You then configure it using this command:

git config --global credential.helper manager

Git will then run the git-credential-manager.exe when authenticating to any server.

Regular Expressions: Search in list

Full Example (Python 3):
For Python 2.x look into Note below

import re

mylist = ["dog", "cat", "wildcat", "thundercat", "cow", "hooo"]
r = re.compile(".*cat")
newlist = list(filter(r.match, mylist)) # Read Note


['cat', 'wildcat', 'thundercat']


For Python 2.x developers, filter returns a list already. In Python 3.x filter was changed to return an iterator so it has to be converted to list (in order to see it printed out nicely).

Python 3 code example
Python 2.x code example

Manually raising (throwing) an exception in Python

Another way to throw an exceptions is assert. You can use assert to verify a condition is being fulfilled if not then it will raise AssertionError. For more details have a look here.

def avg(marks):
    assert len(marks) != 0,"List is empty."
    return sum(marks)/len(marks)

mark2 = [55,88,78,90,79]
print("Average of mark2:",avg(mark2))

mark1 = []
print("Average of mark1:",avg(mark1))

Laravel 5.4 redirection to custom url after login

in accord with Laravel documentation, I create in app/Http/Controllers/Auth/LoginController.php the following method :

protected function redirectTo()

    if($user->account_type == 1){
        return '/admin';
        return '/home';


to get the user information from my db I used "Illuminate\Support\Facades\Auth;".

Explanation of "ClassCastException" in Java

You can better understand ClassCastException and casting once you realize that the JVM cannot guess the unknown. If B is an instance of A it has more class members and methods on the heap than A. The JVM cannot guess how to cast A to B since the mapping target is larger, and the JVM will not know how to fill the additional members.

But if A was an instance of B, it would be possible, because A is a reference to a complete instance of B, so the mapping will be one-to-one.

Python Selenium accessing HTML source

from bs4 import BeautifulSoup
from selenium import webdriver

driver = webdriver.Chrome()
html_source_code = driver.execute_script("return document.body.innerHTML;")
html_soup: BeautifulSoup = BeautifulSoup(html_source_code, 'html.parser')

Now you can apply BeautifulSoup function to extract data...

What should a Multipart HTTP request with multiple files look like?

Well, note that the request contains binary data, so I'm not posting the request as such - instead, I've converted every non-printable-ascii character into a dot (".").

POST /cgi-bin/qtest HTTP/1.1
Host: aram
User-Agent: Mozilla/5.0 Gecko/2009042316 Firefox/3.0.10
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://aram/~martind/banner.htm
Content-Type: multipart/form-data; boundary=2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Length: 514

Content-Disposition: form-data; name="datafile1"; filename="r.gif"
Content-Type: image/gif

Content-Disposition: form-data; name="datafile2"; filename="g.gif"
Content-Type: image/gif

Content-Disposition: form-data; name="datafile3"; filename="b.gif"
Content-Type: image/gif


Note that every line (including the last one) is terminated by a \r\n sequence.

get current page from url


Another option.

How to obtain values of request variables using Python and Flask

Adding more to Jason's more generalized way of retrieving the POST data or GET data

from flask_restful import reqparse

def parse_arg_from_requests(arg, **kwargs):
    parse = reqparse.RequestParser()
    parse.add_argument(arg, **kwargs)
    args = parse.parse_args()
    return args[arg]

form_field_value = parse_arg_from_requests('FormFieldValue')

How to make (link)button function as hyperlink?

You can use OnClientClick event to call a JavaScript function:

<asp:Button ID="Button1" runat="server" Text="Button" onclientclick='redirect()' />

JavaScript code:

function redirect() {
  location.href = 'page.aspx';

But i think the best would be to style a hyperlink with css.

Example :

.button {
  display: block;
  height: 25px;
  background: #f1f1f1;
  padding: 10px;
  text-align: center;
  border-radius: 5px;
  border: 1px solid #e1e1e2;
  color: #000;
  font-weight: bold;

Onchange open URL via select - jQuery

It is pretty simple, let's see a working example:

<select id="dynamic_select">
  <option value="" selected>Pick a Website</option>
  <option value="">Google</option>
  <option value="">YouTube</option>
  <option value="">GuruStop.NET</option>

      // bind change event to select
      $('#dynamic_select').on('change', function () {
          var url = $(this).val(); // get selected value
          if (url) { // require a URL
              window.location = url; // redirect
          return false;

$(function() {_x000D_
  // bind change event to select_x000D_
  $('#dynamic_select').on('change', function() {_x000D_
    var url = $(this).val(); // get selected value_x000D_
    if (url) { // require a URL_x000D_
      window.location = url; // redirect_x000D_
    return false;_x000D_
<select id="dynamic_select">_x000D_
  <option value="" selected>Pick a Website</option>_x000D_
  <option value="">Google</option>_x000D_
  <option value="">YouTube</option>_x000D_
  <option value="">GuruStop.NET</option>_x000D_
<script src=""_x000D_



  • The question specifies jQuery already. So, I'm keeping other alternatives out of this.
  • In older versions of jQuery (< 1.7), you may want to replace on with bind.
  • This is extracted from JavaScript tips in Meligy’s Web Developers Newsletter.


Cannot implicitly convert type 'System.Linq.IQueryable' to 'System.Collections.Generic.IList'

If using a where clause be sure to include .First() if you do not want a IQueryable object.

Default text which won't be shown in drop-down list

Kyle's solution worked perfectly fine for me so I made my research in order to avoid any Js and CSS, but just sticking with HTML. Adding a value of selected to the item we want to appear as a header forces it to show in the first place as a placeholder. Something like:

<option selected disabled>Choose here</option>

The complete markup should be along these lines:

    <option selected disabled>Choose here</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
    <option value="4">Four</option>
    <option value="5">Five</option>

You can take a look at this fiddle, and here's the result:

enter image description here

If you do not want the sort of placeholder text to appear listed in the options once a user clicks on the select box just add the hidden attribute like so:

    <option selected disabled hidden>Choose here</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
    <option value="4">Four</option>
    <option value="5">Five</option>

Check the fiddle here and the screenshot below.

enter image description here

Here is the solution:

    <option style="display:none;" selected>Select language</option>
    <option>Option 1</option>
    <option>Option 2</option>

In laymans terms, what does 'static' mean in Java?

static means that the variable or method marked as such is available at the class level. In other words, you don't need to create an instance of the class to access it.

public class Foo {
    public static void doStuff(){
        // does stuff

So, instead of creating an instance of Foo and then calling doStuff like this:

Foo f = new Foo();

You just call the method directly against the class, like so:


Uncaught (in promise): Error: StaticInjectorError(AppModule)[options]

In my case, the error was in using angular2-notifications 0.9.8 instead of 0.9.7

Testing if a checkbox is checked with jQuery

If you want integer value of checked or not, try:


How to catch a click event on a button?

Just declare a method,e.g:if ur button id is button1 then,

button1.setOnClickListener(new View.OnClickListener(){
        public void onClick(View v) {
            // TODO Auto-generated method stub
            Toast.makeText(Context, "Hello", Toast.LENGTH_SHORT).show();

If you want to make the imageview1 visible then in that method write:


Check if year is leap year in javascript

function leapYear(year)
  return ((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0);

How to create a temporary table in SSIS control flow task and then use it in data flow task?

I'm late to this party but I'd like to add one bit to user756519's thorough, excellent answer. I don't believe the "RetainSameConnection on the Connection Manager" property is relevant in this instance based on my recent experience. In my case, the relevant point was their advice to set "ValidateExternalMetadata" to False.

I'm using a temp table to facilitate copying data from one database (and server) to another, hence the reason "RetainSameConnection" was not relevant in my particular case. And I don't believe it is important to accomplish what is happening in this example either, as thorough as it is.

How to kill an application with all its activities?

My understanding of the Android application framework is that this is specifically not permitted. An application is closed automatically when it contains no more current activities. Trying to create a "kill" button is apparently contrary to the intended design of the application system.

To get the sort of effect you want, you could initiate your various activities with startActivityForResult(), and have the exit button send back a result which tells the parent activity to finish(). That activity could then send the same result as part of its onDestroy(), which would cascade back to the main activity and result in no running activities, which should cause the app to close.

How to input a string from user into environment variable from batch file

You can use set with the /p argument:

SET /P variable=[promptString]

The /P switch allows you to set the value of a variable to a line of input entered by the user. Displays the specified promptString before reading the line of input. The promptString can be empty.

So, simply use something like

set /p Input=Enter some text: 

Later you can use that variable as argument to a command:

myCommand %Input%

Be careful though, that if your input might contain spaces it's probably a good idea to quote it:

myCommand "%Input%"

Add characters to a string in Javascript

You can also keep adding strings to an existing string like so:

var myString = "Hello ";
myString += "World";
myString += "!";

the result would be -> Hello World!

Less aggressive compilation with CSS3 calc

Less no longer evaluates expression inside calc by default since v3.00.

Original answer (Less v1.x...2.x):

Do this:

body { width: calc(~"100% - 250px - 1.5em"); }

In Less 1.4.0 we will have a strictMaths option which requires all Less calculations to be within brackets, so the calc will work "out-of-the-box". This is an option since it is a major breaking change. Early betas of 1.4.0 had this option on by default. The release version has it off by default.

Can Mysql Split a column?

It seems to work:

substring_index ( substring_index ( context,',',1 ), ',', -1) 
substring_index ( substring_index ( context,',',2 ), ',', -1)
substring_index ( substring_index ( context,',',3 ), ',', -1)
substring_index ( substring_index ( context,',',4 ), ',', -1)

it means 1st value, 2nd, 3rd, etc.


The inner substring_index returns the first n values that are comma separated. So if your original string is "34,7,23,89", substring_index( context,',', 3) returns "34,7,23".
The outer substring_index takes the value returned by the inner substring_index and the -1 allows you to take the last value. So you get "23" from the "34,7,23".
Instead of -1 if you specify -2, you'll get "7,23", because it took the last two values.


select * from MyTable where substring_index(substring_index(prices,',',1),',',-1)=3382;

Here, prices is the name of a column in MyTable.

How to determine the IP address of a Solaris system

/usr/sbin/host `hostname`

should do the trick. Bear in mind that it's a pretty common configuration for a solaris box to have several IP addresses, though, in which case

 /usr/sbin/ifconfig -a inet | awk '/inet/ {print $2}'

will list them all

'numpy.float64' object is not iterable

numpy.linspace() gives you a one-dimensional NumPy array. For example:

>>> my_array = numpy.linspace(1, 10, 10)
>>> my_array
array([  1.,   2.,   3.,   4.,   5.,   6.,   7.,   8.,   9.,  10.])


for index,point in my_array

cannot work. You would need some kind of two-dimensional array with two elements in the second dimension:

>>> two_d = numpy.array([[1, 2], [4, 5]])
>>> two_d
array([[1, 2], [4, 5]])

Now you can do this:

>>> for x, y in two_d:
    print(x, y)

1 2
4 5

Function of Project > Clean in Eclipse

I also faced the same issue with Eclipse when I ran the clean build with Maven, but there is a simple solution for this issue. We just need to run Maven update and then build or direct run the application. I hope it will solve the problem.

md-table - How to update the column width

Sample Mat-table column and corresponding CSS:


<ng-container matColumnDef="">
  <mat-header-cell *matHeaderCellDef>
     Wider Column Header
  <mat-cell *matCellDef="let displayData">
    {{ displayData.value}}
  </mat-cell>`enter code here`


.mat-column-courtFolderId {
    flex: 0 0 35%;

Dynamically add script tag with src that may include document.write

I tried it by recursively appending each script

Note If your scripts are dependent one after other, then position will need to be in sync.

Major Dependency should be in last in array so that initial scripts can use it

const scripts = ['', '', '']_x000D_
let count = 0_x000D_
 const recursivelyAddScript = (script, cb) => {_x000D_
  const el = document.createElement('script')_x000D_
  el.src = script_x000D_
  if(count < scripts.length) {_x000D_
    count ++_x000D_
    el.onload = recursivelyAddScript(scripts[count])_x000D_
  } else {_x000D_
    console.log('All script loaded')_x000D_

PHP/MySQL: How to create a comment section in your website

It's a hard question to answer without more information. There are a number of things you should consider when looking at implementing commenting on an existing website.

How will you address the issue of spam? It doesn't matter how remote your website is, spammers WILL find it and they'll filled it up in no time. You may want to look into something like reCAPTCHA (

The structure of the website may also influence how you implement your comments. Are the comments for the overall site, a particular product or page, or even another comment? You'll need to know the relationship between the content and the comment so you can properly define the relationship in the database. To put it another way, you know you want an email address, the comment, and whether it is approved or not, but now we need a way to identify what, if anything, the comment is linked to.

If your site is already established and built on a PHP framework (CakePHP for instance) you'll need to address how to integrate your code properly with what is already in place.

Lastly, there are a number of resources and tutorials on the web for PHP. If you do a quick google search for something along the lines of "PHP blog tutorial" I'm sure you'll find hundreds and the majority will show you step by step how to implement comments.

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.

Which rows are returned when using LIMIT with OFFSET in MySQL?

OFFSET is nothing but a keyword to indicate starting cursor in table

SELECT column FROM table LIMIT 18 OFFSET 8 -- fetch 18 records, begin with record 9 (OFFSET 8)

you would get the same result form

SELECT column FROM table LIMIT 8, 18

visual representation (R is one record in the table in some order)

 OFFSET        LIMIT          rest of the table
 __||__   _______||_______   __||__
/      \ /                \ /
             your result

How do I connect to mongodb with node.js (and authenticate)?

Here is new may to authenticate from "admin" and then switch to your desired DB for further operations:

   var MongoClient = require('mongodb').MongoClient;
var Db = require('mongodb').Db, Server = require('mongodb').Server ,
    assert = require('assert');

var user = 'user';
var password = 'password';

MongoClient.connect('mongodb://'+user+':'+password+'@localhost:27017/opsdb',{native_parser:true, authSource:'admin'}, function(err,db){
        console.log("Auth Failed");
    db.collection("cols").find({loc:{ $eq: null } }, function(err, docs) {
        docs.each(function(err, doc) {
          if(doc) {



Checking if a number is an Integer in Java

One example more :)

double a = 1.00

if(floor(a) == a) {
   // a is an integer
} else {
   //a is not an integer.

In this example, ceil can be used and have the exact same effect.

Mysql service is missing

If you wish to have your config file on a different path you have to give your service a name:

mysqld --install NAME --defaults-file=C:\my-opts2.cnf

You can also use the name to install multiple mysql services listening on different sockets if you need that for some reason. You can see why it's failing by copying the execution path and adding --console to the end in the terminal. Finally, you can modify the starting path of a service by regediting:


That works well but it isn't as useful because the windows service mechanism provides little logging capabilities.

How to pass a datetime parameter?

One possible solution is to use Ticks:

public long Ticks { get; }

Then in the controller's method:

public DateTime(long ticks);

Rails: Get Client IP address

Get client ip using command:


How many parameters are too many?

A function can only have too many parameters if some of the parameters are redundant. If all the parameters are used, the function must have the correct number of parameters. Take this often used function:

HWND CreateWindowEx
  DWORD dwExStyle,
  LPCTSTR lpClassName,
  LPCTSTR lpWindowName,
  DWORD dwStyle,
  int x,
  int y,
  int nWidth,
  int nHeight,
  HWND hWndParent,
  HMENU hMenu,
  HINSTANCE hInstance,
  LPVOID lpParam

That's 12 parameters (9 if you bundle the x,y,w and h as a rectangle) and there's also the parameters derived from the class name as well. How would you reduce this? Would you want to reduce the number more to the point?

Don't let the number of parameters bother you, just make sure it's logical and well documented and let intellisense* help you.

* Other coding assistants are available!

How to add minutes to my Date

There's an error in the pattern of your SimpleDateFormat. it should be

SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm");

What is the meaning of ImagePullBackOff status on a Kubernetes pod?

The issue arises when the image is not present on the cluster and k8s engine is going to pull the respective registry. k8s Engine enables 3 types of ImagePullPolicy mentioned :

  1. Always : It always pull the image in container irrespective of changes in the image
  2. Never : It will never pull the new image on the container
  3. IfNotPresent : It will pull the new image in cluster if the image is not present.

Best Practices : It is always recommended to tag the new image in both docker file as well as k8s deployment file. So That it can pull the new image in container.

What's the difference between SHA and AES encryption?

SHA isn't encryption, it's a one-way hash function. AES (Advanced_Encryption_Standard) is a symmetric encryption standard.

AES Reference

Artisan, creating tables in database

Migration files must match the pattern *_*.php, or else they won't be found. Since users.php does not match this pattern (it has no underscore), this file will not be found by the migrator.

Ideally, you should be creating your migration files using artisan:

php artisan make:migration create_users_table

This will create the file with the appropriate name, which you can then edit to flesh out your migration. The name will also include the timestamp, to help the migrator determine the order of migrations.

You can also use the --create or --table switches to add a little bit more boilerplate to help get you started:

php artisan make:migration create_users_table --create=users

The documentation on migrations can be found here.

how to split the ng-repeat data with three columns using bootstrap

Just in case someone wants an Angular 7 (and higher version) here is an example I used in one of my applications:


                   <div class="container-fluid">_x000D_
                    <div class="row" *ngFor="let reports of chunkData; index as i">_x000D_
                        <div *ngFor="let report of reports" class="col-4 col-sm-4"_x000D_
                            style="border-style:solid;background-color: antiquewhite">{{report}}</div>_x000D_


export class ConfirmationPageComponent implements OnInit {_x000D_
  chunkData = [];_x000D_
  reportsArray = ["item 1", "item 2", "item 3", "item 4", "item 5", "item 6"];_x000D_
  constructor() {}_x000D_
  ngOnInit() {_x000D_
    this.chunkData = this.chunk(this.reportsArray, 3);_x000D_
  chunk(arr, size) {_x000D_
    var newArr = [];_x000D_
    for (var i = 0; i < arr.length; i += size) {_x000D_
      newArr.push(arr.slice(i, i + size));_x000D_
    return newArr;_x000D_

This is an awesome solution for dynamically creating new columns/rows depending on how much items your iterating from the database. THanks!

SMTP error 554

To resolve problem go to the MDaemon-->setup-->Miscellaneous options-->Server-->SMTP Server Checks commands and headers for RFC Compliance

Get Selected value from dropdown using JavaScript


var e = document.getElementById("mySelect");
var selectedOp = e.options[e.selectedIndex].text;

How to resize the jQuery DatePicker control

I had datepicker appearing in a modal and because of the "date-display-container" on the left hand side, the calendar was partially out of view, so I added:

.datepicker-date-display {
  display: none;

.datepicker-calendar-container {
  max-height: 21em;
.datepicker-day-button {
  line-height: 1.2em;

.datepicker-table > thead > tr > th {
  padding: 0;

Responsive Images with CSS

Use max-width on the images too. Change:

.erb-image-wrapper img{
    width:100% !important;
    height:100% !important;


.erb-image-wrapper img{
    max-width:100% !important;
    max-height:100% !important;

firefox proxy settings via command line

I don't think there is a direct way to set the proxy (on Windows).

You could however install an add-on like FoxyProxy, create several configurations for different proxies and prior to starting FireFox move the appropriate configuration to the correct folder in your FireFox profile (using a batch file).

How to concatenate two strings to build a complete path

I was working around with my shell script which need to do some path joining stuff like you do.

The thing is, both path like



are valid.

If I want to append a file to this path like


there was no native method (like os.path.join() in python) in shell to handle such situation.

But I did found a trick

For example , the base path was store in a shell variable


and the last file name you wanna join was


Then you can assign your new path like this

NEW_PATH=$(realpath ${BASE})/FILE

and then you`ll get

$ echo $NEW_PATH


the reason is quiet simple, the "realpath" command would always trim the terminating slash for you if necessary

How to find length of digits in an integer?

It's been several years since this question was asked, but I have compiled a benchmark of several methods to calculate the length of an integer.

def libc_size(i): 
    return libc.snprintf(buf, 100, c_char_p(b'%i'), i) # equivalent to `return snprintf(buf, 100, "%i", i);`

def str_size(i):
    return len(str(i)) # Length of `i` as a string

def math_size(i):
    return 1 + math.floor(math.log10(i)) # 1 + floor of log10 of i

def exp_size(i):
    return int("{:.5e}".format(i).split("e")[1]) + 1 # e.g. `1e10` -> `10` + 1 -> 11

def mod_size(i):
    return len("%i" % i) # Uses string modulo instead of str(i)

def fmt_size(i):
    return len("{0}".format(i)) # Same as above but str.format

(the libc function requires some setup, which I haven't included)

size_exp is thanks to Brian Preslopsky, size_str is thanks to GeekTantra, and size_math is thanks to John La Rooy

Here are the results:

Time for libc size:      1.2204 µs
Time for string size:    309.41 ns
Time for math size:      329.54 ns
Time for exp size:       1.4902 µs
Time for mod size:       249.36 ns
Time for fmt size:       336.63 ns
In order of speed (fastest first):
+ mod_size (1.000000x)
+ str_size (1.240835x)
+ math_size (1.321577x)
+ fmt_size (1.350007x)
+ libc_size (4.894290x)
+ exp_size (5.976219x)

(Disclaimer: the function is run on inputs 1 to 1,000,000)

Here are the results for sys.maxsize - 100000 to sys.maxsize:

Time for libc size:      1.4686 µs
Time for string size:    395.76 ns
Time for math size:      485.94 ns
Time for exp size:       1.6826 µs
Time for mod size:       364.25 ns
Time for fmt size:       453.06 ns
In order of speed (fastest first):
+ mod_size (1.000000x)
+ str_size (1.086498x)
+ fmt_size (1.243817x)
+ math_size (1.334066x)
+ libc_size (4.031780x)
+ exp_size (4.619188x)

As you can see, mod_size (len("%i" % i)) is the fastest, slightly faster than using str(i) and significantly faster than others.

Make browser window blink in task Bar

You may want to try window.focus() - but it may be annoying if the screen switches around

How can I make a JUnit test wait?

If it is an absolute must to generate delay in a test CountDownLatch is a simple solution. In your test class declare:

private final CountDownLatch waiter = new CountDownLatch(1);

and in the test where needed:

waiter.await(1000 * 1000, TimeUnit.NANOSECONDS); // 1ms

Maybe unnecessary to say but keeping in mind that you should keep wait times small and not cumulate waits to too many places.

Google Drive as FTP Server

I couldn't find a direct GDrive/DropBox solution. I'm also surprised there's no lazy solution for a free ftp host. Windows azure offers a ftp server "FTP connector" that's fairly easy to turn on at:

You can get a free 1 GB account by selecting "View All" machine types during your deployment.

How to select an option from drop down using Selenium WebDriver C#?

Other way could be this one:


and you can change the index in option[x] changing x by the number of element that you want to select.

I don't know if it is the best way but I hope that help you.

Export pictures from excel file into jpg using VBA

Here is another cool way to do it- using en external viewer that accepts command line switches (IrfanView in this case) : * I based the loop on what Michal Krzych has written above.

Sub ExportPicturesToFiles()
    Const saveSceenshotTo As String = "C:\temp\"
    Const pictureFormat As String = ".jpg"

    Dim pic As Shape
    Dim sFileName As String
    Dim i As Long

    i = 1

    For Each pic In ActiveSheet.Shapes
        sFileName = saveSceenshotTo & Range("A" & i).Text & pictureFormat

        Call ExportPicWithIfran(sFileName)

        i = i + 1
End Sub

Public Sub ExportPicWithIfran(sSaveAsPath As String)
    Const sIfranPath As String = "C:\Program Files\IrfanView\i_view32.exe"
    Dim sRunIfran As String

    sRunIfran = sIfranPath & " /clippaste /convert=" & _
                            sSaveAsPath & " /killmesoftly"

    ' Shell is no good here. If you have more than 1 pic, it will
    ' mess things up (pics will over run other pics, becuase Shell does
    ' not make vba wait for the script to finish).
    ' Shell sRunIfran, vbHide

    ' Correct way (it will now wait for the batch to finish):
    call MyShell(sRunIfran )
End Sub


  Private Sub MyShell(strShell As String)
  ' based on:
   ' by Nate Hekman

    Dim wsh As Object
    Dim waitOnReturn As Boolean:
    Dim windowStyle As VbAppWinStyle

    Set wsh = VBA.CreateObject("WScript.Shell")
    waitOnReturn = True
    windowStyle = vbHide

    wsh.Run strShell, windowStyle, waitOnReturn
End Sub

Get list from pandas DataFrame column headers

as answered by Simeon could do



list(my_dataframe) # for less typing.

But I think most the sweet spot is:


It is explicit, at the same time not unnecessarily long.

'python' is not recognized as an internal or external command

i solved this by running CMD in administration mode, so try this.

How to get cookie expiration date / creation date from javascript?

Yes, It is possible. I've separated the code in two files:



    $time = time()+(60*60*24*10);
    $timeMemo = (string)$time;
    setcookie("cookie", "" . $timeMemo . "", $time);

            Get cookie expiration date from JS
        <script type="text/javascript">

            function cookieExpirationDate(){

                var infodiv = document.getElementById("info");

                var xmlhttp;
                if (window.XMLHttpRequest){ 
                    xmlhttp = new XMLHttpRequest;
                    xmlhttp = new ActiveXObject(Microsoft.XMLHTTP);

                xmlhttp.onreadystatechange = function (){
                    if(xmlhttp.readyState == 4 && xmlhttp.status == 200){
                        infodiv.innerHTML = xmlhttp.responseText;

      "GET", "cookie.php", true);


        <input type="button" onclick="javascript:cookieExpirationDate();" value="Get Cookie expire date" />
        <hr />
        <div id="info">



    function secToDays($sec){
        return ($sec / 60 / 60 / 24);


        if(round(secToDays((intval($_COOKIE['cookie']) - time())),1) < 1){
            echo "Cookie will expire today";
            echo "Cookie will expire in " . round(secToDays((intval($_COOKIE['cookie']) - time())),1) . " day(s)";
        echo "Cookie not set...";


Now, index.php must be loaded once. The button "Get Cookie expire date", thru an AJAX request, will always get you an updated "time left" for cookie expiration, in this case in days.

How should I do integer division in Perl?

Eg 9 / 4 = 2.25

int(9) / int(4) = 2

9 / 4 - remainder / deniminator = 2

9 /4 - 9 % 4 / 4 = 2

How do you add UI inside cells in a google spreadsheet using app script?

Buttons can be added to frozen rows as images. Assigning a function within the attached script to the button makes it possible to run the function. The comment which says you can not is of course a very old comment, possibly things have changed now.

Is <div style="width: ;height: ;background: "> CSS?

1)Yes it is, when there is style then it is styling your code(css).2) is belong to html it is like a container that keep your css.

Appending to 2D lists in Python

[[]]*3 is not the same as [[], [], []].

It's as if you'd said

a = []
listy = [a, a, a]

In other words, all three list references refer to the same list instance.

How to change root logging level programmatically for logback

I assume you are using logback (from the configuration file).

From logback manual, I see

Logger rootLogger = LoggerFactory.getLogger(org.slf4j.Logger.ROOT_LOGGER_NAME);

Perhaps this can help you change the value?

How to vertically center content with variable height within a div?

Best result for me so far:

div to be centered:

position: absolute;
top: 50%;
transform: translateY(-50%);
margin: 0 auto;
right: 0;
left: 0;

Could not connect to SMTP host: localhost, port: 25; nested exception is: Connection refused: connect

First you have to ensure that there is a SMTP server listening on port 25.

To look whether you have the service, you can try using TELNET client, such as:

C:\> telnet localhost 25

(telnet client by default is disabled on most recent versions of Windows, you have to add/enable the Windows component from Control Panel. In Linux/UNIX usually telnet client is there by default.

$ telnet localhost 25

If it waits for long then time out, that means you don't have the required SMTP service. If successfully connected you enter something and able to type something, the service is there.

If you don't have the service, you can use these:

  • A mock SMTP server that will mimic the behavior of actual SMTP server, as you are using Java, it is natural to suggest Dumbster fake SMTP server. This even can be made to work within JUnit tests (with setup/tear down/validation), or independently run as separate process for integration test.
  • If your host is Windows, you can try installing Mercury email server (also comes with WAMPP package from Apache Friends) on your local before running above code.
  • If your host is Linux or UNIX, try to enable the mail service such as Postfix,
  • Another full blown SMTP server in Java, such as Apache James mail server.

If you are sure that you already have the service, may be the SMTP requires additional security credentials. If you can tell me what SMTP server listening on port 25 I may be able to tell you more.

How do I do pagination in ASP.NET MVC?

I had the same problem and found a very elegant solution for a Pager Class from

In your controller the call looks like:

return View(partnerList.ToPagedList(currentPageIndex, pageSize));

and in your view:

<div class="pager">
    Seite: <%= Html.Pager(ViewData.Model.PageSize, 

Sending intent to BroadcastReceiver from adb

I've found that the command was wrong, correct command contains "broadcast" instead of "start":

adb shell am broadcast -a com.whereismywifeserver.intent.TEST --es sms_body "test from adb" -n com.whereismywifeserver/.IntentReceiver

How to Update a Component without refreshing full page - Angular

To refresh the component at regular intervals I found this the best method. In the ngOnInit method setTimeOut function

ngOnInit(): void {
  setTimeout(() => { this.ngOnInit() }, 1000 * 10)
//10 is the number of seconds

Traits vs. interfaces

If you know English and know what trait means, it is exactly what the name says. It is a class-less pack of methods and properties you attach to existing classes by typing use.

Basically, you could compare it to a single variable. Closures functions can use these variables from outside of the scope and that way they have the value inside. They are powerful and can be used in everything. Same happens to traits if they are being used.

What does a bitwise shift (left or right) do and what is it used for?

Yes, I think performance-wise you might find a difference as bitwise left and right shift operations can be performed with a complexity of o(1) with a huge data set.

For example, calculating the power of 2 ^ n:

int value = 1;
while (exponent<n)
       // Print out current power of 2
        value = value *2; // Equivalent machine level left shift bit wise operation

Similar code with a bitwise left shift operation would be like:

value = 1 << n;

Moreover, performing a bit-wise operation is like exacting a replica of user level mathematical operations (which is the final machine level instructions processed by the microcontroller and processor).

Error inflating class

Sorry Guys. I have solved this Issue long ago. I did a lot of changes. So I can't figure out which one does the trick.

  1. I have changed the id as suggested by Jared Burrows.

  2. Removed my support library and cleaned my project and Re added it.

  3. Go to File -> Invalidate Caches/Restart.

Hope it works.

This is how my code looks now


<?xml version="1.0" encoding="utf-8"?>






<?xml version="1.0" encoding="utf-8"?>


<style name="ToolBarStyle" parent="">
        <item name="popupTheme">@style/ThemeOverlay.AppCompat.Light</item>
        <item name="theme">@style/ThemeOverlay.AppCompat.Dark.ActionBar</item>

Run php script as daemon process

You could start your php script from the command line (i.e. bash) by using

nohup php myscript.php &

the & puts your process in the background.

Yes, there are some drawbacks, but not possible to control? That's just wrong.
A simple kill processid will stop it. And it's still the best and simplest solution.

AngularJs directive not updating another directive's scope

Just wondering why you are using 2 directives?

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

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

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

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

Transfer data between databases with PostgreSQL

There are three options for copying it if this is a one off:

  1. Use a db_link (I think it is still in contrib)
  2. Have the application do the work.
  3. Export/import

If this is an ongoing need, the answers are:

  1. Change to schemas in the same DB
  2. db_link

Calling a Variable from another Class

You need to specify an access modifier for your variable. In this case you want it public.

public class Variables
    public static string name = "";

After this you can use the variable like this.

Ways to save enums in database

For a large database, I am reluctant to lose the size and speed advantages of the numeric representation. I often end up with a database table representing the Enum.

You can enforce database consistency by declaring a foreign key -- although in some cases it might be better to not declare that as a foreign key constraint, which imposes a cost on every transaction. You can ensure consistency by periodically doing a check, at times of your choosing, with:

SELECT reftable.* FROM reftable
  LEFT JOIN enumtable ON reftable.enum_ref_id = enumtable.enum_id
WHERE enumtable.enum_id IS NULL;

The other half of this solution is to write some test code that checks that the Java enum and the database enum table have the same contents. That's left as an exercise for the reader.

Angular 2: How to access an HTTP response body?

The response data are in JSON string form. The app must parse that string into JavaScript objects by calling response.json().

  .map(res => res.json())
  .subscribe(data => {

Bootstrap 3 - Set Container Width to 940px Maximum for Desktops?

There is a far easier solution (IMO) in Bootstrap 3 that does not require you to compile any custom LESS. You just have to leverage the cascade in "Cascading Style Sheets."

Set up your CSS loading like so...

<link type="text/css" rel="stylesheet" href="/css/bootstrap.css" />
<link type="text/css" rel="stylesheet" href="/css/custom.css" />

Where /css/custom.css is your unique style definitions. Inside that file, add the following definition...

@media (min-width: 1200px) {
  .container {
    width: 970px;

This will override Bootstrap's default width: 1170px setting when the viewport is 1200px or bigger.

Tested in Bootstrap 3.0.2

convert string date to java.sql.Date

This works for me without throwing an exception:

package com.sandbox;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Sandbox {

    public static void main(String[] args) throws ParseException {
        SimpleDateFormat format = new SimpleDateFormat("yyyyMMdd");
        Date parsed = format.parse("20110210");
        java.sql.Date sql = new java.sql.Date(parsed.getTime());


How do I run Python code from Sublime Text 2?

seems the Ctrl+Break doesn't work on me, neither the Preference - User...

use keys, Alt ? t ? c

CSS Classes & SubClasses

Just put a space between .area1 and .item, e.g:

.area1 .item

this style applies to elements with class item inside an element with class area1.

jquery clear input default value

Just a shorthand

$(document).ready(function() {
    $(".input").val("Email Address");
        $(".input").on("focus click", function(){

CSS text-decoration underline color

You can't change the color of the line (you can't specify different foreground colors for the same element, and the text and its decoration form a single element). However there are some tricks:

a:link, a:visited {text-decoration: none; color: red; border-bottom: 1px solid #006699; }
a:hover, a:active {text-decoration: none; color: red; border-bottom: 1px solid #1177FF; }

Also you can make some cool effects this way:

a:link {text-decoration: none; color: red; border-bottom: 1px dashed #006699; }

Hope it helps.

Creating C formatted strings (not printing them)

It sounds to me like you want to be able to easily pass a string created using printf-style formatting to the function you already have that takes a simple string. You can create a wrapper function using stdarg.h facilities and vsnprintf() (which may not be readily available, depending on your compiler/platform):

#include <stdarg.h>
#include <stdio.h>

// a function that accepts a string:

void foo( char* s);

// You'd like to call a function that takes a format string 
//  and then calls foo():

void foofmt( char* fmt, ...)
    char buf[100];     // this should really be sized appropriately
                       // possibly in response to a call to vsnprintf()
    va_list vl;
    va_start(vl, fmt);

    vsnprintf( buf, sizeof( buf), fmt, vl);

    va_end( vl);

    foo( buf);

int main()
    int val = 42;

    foofmt( "Some value: %d\n", val);
    return 0;

For platforms that don't provide a good implementation (or any implementation) of the snprintf() family of routines, I've successfully used a nearly public domain snprintf() from Holger Weiss.

EditText, inputType values (xml)

Supplemental answer

Here is how the standard keyboard behaves for each of these input types.

enter image description here

See this answer for more details.

How to change file encoding in NetBeans?

Yes, you can change the encoding of a specific file (or see what it has) with this Encoding Support plugin. With this plugin you will be able to handle the different encodings of your files without problems.

Now it is in version 1.4.0 for NetBeans 8.2 and I use it in Windows 10 several time ago.

The operation is very simple, in the status line you can see the encoding of the open file, and from there you can define its new encoding.

Encoding Support running on Windows 10

Change image source in code behind - Wpf

None of the above solutions worked for me. But this did:

myImage.Source = new BitmapImage(new Uri(@"/Images/foo.png", UriKind.Relative));

Form Submit jQuery does not work

Alright, this doesn't apply to the OP's exact situation, but for anyone like myself who comes here facing a similar issue, figure I should throw this out there-- maybe save a headache or two.

If you're using an non-standard "button" to ensure the submit event isn't called:

  <input type="hidden" name="hide" value="1">
  <a href="#" onclick="submitWithChecked(this.form)">Hide Selected</a>

Then, when you try to access this.form in the script, it's going to come up undefined. As I discovered, apparently anchor elements don't have same access to a parent form element the way your standard form elements do.

In such cases, (again, assuming you are intentionally avoiding the submit event for the time-being), you can use a button with type="button"

  <input type="hidden" name="hide" value="1">
  <button type="button" onclick="submitWithChecked(this.form)">Hide Selected</a>

(Addendum 2020: All these years later, I think the more important lesson to take away from this is to check your input. If my function had bothered to check that the argument it received was actually a form element, the problem would have been much easier to catch.)

Aren't Python strings immutable? Then why does a + " " + b work?

The variable a is pointing at the object "Dog". It's best to think of the variable in Python as a tag. You can move the tag to different objects which is what you did when you changed a = "dog" to a = "dog eats treats".

However, immutability refers to the object, not the tag.

If you tried a[1] = 'z' to make "dog" into "dzg", you would get the error:

TypeError: 'str' object does not support item assignment" 

because strings don't support item assignment, thus they are immutable.

JPA Native Query select and cast object

Please refer JPA : How to convert a native query result set to POJO class collection

For Postgres 9.4,

List<String> list = em.createNativeQuery("select cast(row_to_json(u) as text) from myschema.USER_ u WHERE ID = ?")
                   .setParameter(1, id).getResultList();

User map = new ObjectMapper().readValue(list.get(0), User.class);

Reading a text file with SQL Server

Just discovered this:


It'll pull in the contents of the file as varchar(max). Replace SINGLE_CLOB with:

SINGLE_NCLOB for nvarchar(max) SINGLE_BLOB for varbinary(max)

Thanks to for this!

How to change Git log date formats

Git 2.7 (Q4 2015) will introduce -local as an instruction.
It means that, in addition to:


you will also have:


The -local suffix cannot be used with raw or relative. Reference.

You now can ask for any date format using the local timezone. See

See commit add00ba, commit 547ed71 (03 Sep 2015) by Jeff King (peff).
(Merged by Junio C Hamano -- gitster -- in commit 7b09c45, 05 Oct 2015)

In particular, the last from above (commit add00ba) mentions:

date: make "local" orthogonal to date format:

Most of our "--date" modes are about the format of the date: which items we show and in what order.
But "--date=local" is a bit of an oddball. It means "show the date in the normal format, but using the local timezone".
The timezone we use is orthogonal to the actual format, and there is no reason we could not have "localized iso8601", etc.

This patch adds a "local" boolean field to "struct date_mode", and drops the DATE_LOCAL element from the date_mode_type enum (it's now just DATE_NORMAL plus local=1).
The new feature is accessible to users by adding "-local" to any date mode (e.g., "iso-local"), and we retain "local" as an alias for "default-local" for backwards compatibility.

How to set the context path of a web application in Tomcat 7.0

It's not recommended to update the server configuration like server.xml or ROOT.xml.

You can put a context.xml configuration file under your web-application META-INF directory, with the context path setting included. This will override the default server setting?


<Context docBase="yourAppName" path="/yourAppPath" reloadable="true">

returning a Void object

It is possible to create instances of Void if you change the security manager, so something like this:

static Void getVoid() throws SecurityException, InstantiationException,
        IllegalAccessException, InvocationTargetException {
    class BadSecurityManager extends SecurityManager {
        public void checkPermission(Permission perm) { }
        public void checkPackageAccess(String pkg) { }

    System.setSecurityManager(badManager = new BadSecurityManager());
    Constructor<?> constructor = Void.class.getDeclaredConstructors()[0];
    if(!constructor.isAccessible()) {
    return (Void) constructor.newInstance();

Obviously this is not all that practical or safe; however, it will return an instance of Void if you are able to change the security manager.

GZIPInputStream reading line by line

here is with one line

try (BufferedReader br = new BufferedReader(
        new InputStreamReader(
           new GZIPInputStream(
              new FileInputStream(

Send data from a textbox into Flask?

Declare a Flask endpoint to accept POST input type and then do necessary steps. Use jQuery to post the data.

from flask import request

@app.route('/parse_data', methods=['GET', 'POST'])
def parse_data(data):
    if request.method == "POST":
         #perform action here
var value = $('.textbox').val();
  type: 'POST',
  url: "{{ url_for('parse_data') }}",
  data: JSON.stringify(value),
  contentType: 'application/json',
  success: function(data){
    // do something with the received data

Get all files and directories in specific path fast

In .NET 4.0 there's the Directory.EnumerateFiles method which returns an IEnumerable<string> and is not loading all the files in memory. It's only once you start iterating over the returned collection that files will be returned and exceptions could be handled.

Returning an array using C

C's treatment of arrays is very different from Java's, and you'll have to adjust your thinking accordingly. Arrays in C are not first-class objects (that is, an array expression does not retain it's "array-ness" in most contexts). In C, an expression of type "N-element array of T" will be implicitly converted ("decay") to an expression of type "pointer to T", except when the array expression is an operand of the sizeof or unary & operators, or if the array expression is a string literal being used to initialize another array in a declaration.

Among other things, this means that you cannot pass an array expression to a function and have it received as an array type; the function actually receives a pointer type:

void foo(char *a, size_t asize)
  // do something with a

int bar(void)
  char str[6] = "Hello";
  foo(str, sizeof str);

In the call to foo, the expression str is converted from type char [6] to char *, which is why the first parameter of foo is declared char *a instead of char a[6]. In sizeof str, since the array expression is an operand of the sizeof operator, it's not converted to a pointer type, so you get the number of bytes in the array (6).

If you're really interested, you can read Dennis Ritchie's The Development of the C Language to understand where this treatment comes from.

The upshot is that functions cannot return array types, which is fine since array expressions cannot be the target of an assignment, either.

The safest method is for the caller to define the array, and pass its address and size to the function that's supposed to write to it:

void returnArray(const char *srcArray, size_t srcSize, char *dstArray, char dstSize)
  dstArray[i] = some_value_derived_from(srcArray[i]);

int main(void)
  char src[] = "This is a test";
  char dst[sizeof src];
  returnArray(src, sizeof src, dst, sizeof dst);

Another method is for the function to allocate the array dynamically and return the pointer and size:

char *returnArray(const char *srcArray, size_t srcSize, size_t *dstSize)
  char *dstArray = malloc(srcSize);
  if (dstArray)
    *dstSize = srcSize;
  return dstArray;

int main(void)
  char src[] = "This is a test";
  char *dst;
  size_t dstSize;

  dst = returnArray(src, sizeof src, &dstSize);

In this case, the caller is responsible for deallocating the array with the free library function.

Note that dst in the above code is a simple pointer to char, not a pointer to an array of char. C's pointer and array semantics are such that you can apply the subscript operator [] to either an expression of array type or pointer type; both src[i] and dst[i] will access the i'th element of the array (even though only src has array type).

You can declare a pointer to an N-element array of T and do something similar:

char (*returnArray(const char *srcArr, size_t srcSize))[SOME_SIZE]
  char (*dstArr)[SOME_SIZE] = malloc(sizeof *dstArr);
  if (dstArr)
    (*dstArr)[i] = ...;
  return dstArr;

int main(void)
  char src[] = "This is a test";
  char (*dst)[SOME_SIZE];
  dst = returnArray(src, sizeof src);
  printf("%c", (*dst)[j]);

Several drawbacks with the above. First of all, older versions of C expect SOME_SIZE to be a compile-time constant, meaning that function will only ever work with one array size. Secondly, you have to dereference the pointer before applying the subscript, which clutters the code. Pointers to arrays work better when you're dealing with multi-dimensional arrays.

What is the purpose of the single underscore "_" variable in Python?

Underscore _ is considered as "I don't Care" or "Throwaway" variable in Python

  • The python interpreter stores the last expression value to the special variable called _.

    >>> 10 
    >>> _ 
    >>> _ * 3 
  • The underscore _ is also used for ignoring the specific values. If you don’t need the specific values or the values are not used, just assign the values to underscore.

    Ignore a value when unpacking

    x, _, y = (1, 2, 3)
    >>> x
    >>> y 

    Ignore the index

    for _ in range(10):     

Catching exceptions from Guzzle

Old question, but Guzzle adds the response within the exception object. So a simple try-catch on GuzzleHttp\Exception\ClientException and then using getResponse on that exception to see what 400-level error and continuing from there.

How add items(Text & Value) to ComboBox & read them in SelectedIndexChanged (SelectedValue = null)

This is similar to some of the other answers, but is compact and avoids the conversion to dictionary if you already have a list.

Given a ComboBox "combobox" on a windows form and a class SomeClass with the string type property Name,

List<SomeClass> list = new List<SomeClass>();

combobox.DisplayMember = "Name";
combobox.DataSource = list;

Which means that combobox.SelectedItem is a SomeClass object from list, and each item in combobox will be displayed using its property Name.

You can read the selected item using

SomeClass someClass = (SomeClass)combobox.SelectedItem;

How can I programmatically freeze the top row of an Excel worksheet in Excel 2007 VBA?

Just hit the same problem... For some reason, the freezepanes command just caused crosshairs to appear in the centre of the screen. It turns oout I had switched ScreenUpdating off! Solved with the following code:

Application.ScreenUpdating = True
Cells(2, 1).Select
ActiveWindow.FreezePanes = True

Now it works fine.

Best way to get whole number part of a Decimal number

By the way guys, (int)Decimal.MaxValue will overflow. You can't get the "int" part of a decimal because the decimal is too friggen big to put in the int box. Just checked... its even too big for a long (Int64).

If you want the bit of a Decimal value to the LEFT of the dot, you need to do this:


and return the value as... A DECIMAL or a DOUBLE.

edit: Truncate is definitely the correct function!

What are the differences between if, else, and else if?

The if statement uses the results of a logical expression to decide if one of two code blocks will be executed.

With this code

if (logical expression) {
    code block 1;
} else {
    code block 2;

if the logical expression is true, only the statements in code block 1 will be executed; if false, only the statements in code block 2.

In the case that there are multiple similar tests to be done (for instance if we are testing a number to be less than zero, equal to zero or more than zero) then the second test can be placed as the first statement of the else code block.

if (logical expression 1) {
    code block 1;
} else {
    if (logical expression 2) {
        code block 2;
    } else {
        code block 3;

In this case, code block 1 is executed if logical expression 1 is true; code block 2 if logical expression 1 is false and logical expression 2 is true; code block 3 if both logical expressions are false.

Obviously this can be repeated with another if statement as the first statement of code block 3.

The else if statement is simply a reformatted version of this code.

if (logical expression 1) {
    code block 1;
} else if (logical expression 2) {
    code block 2;
} else {
    code block 3;

React : difference between <Route exact path="/" /> and <Route path="/" />

Please try this.

            <Route exact path="/" component={Home} />
            <Route path="/news" component={NewsFeed} />


How to find all the tables in MySQL with specific column names in them?


How do I make an image smaller with CSS?

You can resize images using CSS just fine if you're modifying an image tag:

<img src="example.png" style="width:2em; height:3em;" />

You cannot scale a background-image property using CSS2, although you can try the CSS3 property background-size.

What you can do, on the other hand, is to nest an image inside a span. See the answer to this question: Stretch and scale CSS background

Iterating through a variable length array

here is an example, where the length of the array is changed during execution of the loop

import java.util.ArrayList;
public class VariableArrayLengthLoop {

public static void main(String[] args) {

    //create new ArrayList
    ArrayList<String> aListFruits = new ArrayList<String>();

    //add objects to ArrayList

    //iterate ArrayList using for loop
    for(int i = 0; i < aListFruits.size(); i++){

        System.out.println( aListFruits.get(i) + " i = "+i );
         if ( i == 2 ) {
                System.out.println( "added now a Fruit to the List "); 

Getting a union of two arrays in JavaScript

With the arrival of ES6 with sets and splat operator (at the time of being works only in Firefox, check compatibility table), you can write the following cryptic one liner:

var a = [34, 35, 45, 48, 49];_x000D_
var b = [48, 55];_x000D_
var union = [ Set([...a, ...b])];_x000D_

Little explanation about this line: [...a, ...b] concatenates two arrays, you can use a.concat(b) as well. new Set() create a set out of it and thus your union. And the last [...x] converts it back to an array.

POST data to a URL in PHP

If you're looking to post data to a URL from PHP code itself (without using an html form) it can be done with curl. It will look like this:

$url = '';
$myvars = 'myvar1=' . $myvar1 . '&myvar2=' . $myvar2;

$ch = curl_init( $url );
curl_setopt( $ch, CURLOPT_POST, 1);
curl_setopt( $ch, CURLOPT_POSTFIELDS, $myvars);
curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt( $ch, CURLOPT_HEADER, 0);
curl_setopt( $ch, CURLOPT_RETURNTRANSFER, 1);

$response = curl_exec( $ch );

This will send the post variables to the specified url, and what the page returns will be in $response.

ASP.NET 4.5 has not been registered on the Web server

I had the exact same problem, despite ASP.NET 4.5 appearing as installed under "Turn Windows Features On/Off". I tried everything until I finally removed ASP.NET 3.5 and 4.5 completely from under "Turn Windows Features On/Off", rebooted my PC and reinstalled them Again. That solved the problem.

how to do bitwise exclusive or of two strings in python?

I've found that the ''.join(chr(ord(a)^ord(b)) for a,b in zip(s,m)) method is pretty slow. Instead, I've been doing this:

fmt = '%dB' % len(source)
s = struct.unpack(fmt, source)
m = struct.unpack(fmt, xor_data)
final = struct.pack(fmt, *(a ^ b for a, b in izip(s, m)))

converting list to json format - quick and easy way

3 years of experience later, I've come back to this question and would suggest to write it like this:

string output = new JavaScriptSerializer().Serialize(ListOfMyObject);

One line of code.

alternatives to REPLACE on a text or ntext datatype

IF your data won't overflow 4000 characters AND you're on SQL Server 2000 or compatibility level of 8 or SQL Server 2000:

UPDATE [CMS_DB_test].[dbo].[cms_HtmlText] 
SET Content = CAST(REPLACE(CAST(Content as NVarchar(4000)),'ABC','DEF') AS NText)
WHERE Content LIKE '%ABC%' 

For SQL Server 2005+:

UPDATE [CMS_DB_test].[dbo].[cms_HtmlText] 
SET Content = CAST(REPLACE(CAST(Content as NVarchar(MAX)),'ABC','DEF') AS NText)
WHERE Content LIKE '%ABC%' 

How do I resolve `The following packages have unmet dependencies`

The command to have Ubuntu fix unmet dependencies and broken packages is

sudo apt-get install -f

from the man page:

-f, --fix-broken Fix; attempt to correct a system with broken dependencies in place. This option, when used with install/remove, can omit any packages to permit APT to deduce a likely solution. If packages are specified, these have to completely correct the problem. The option is sometimes necessary when running APT for the first time; APT itself does not allow broken package dependencies to exist on a system. It is possible that a system's dependency structure can be so corrupt as to require manual intervention (which usually means using dselect(1) or dpkg --remove to eliminate some of the offending packages)

Ubuntu will try to fix itself when you run the command. When it completes, you can test if it worked by running the command again, and you should receive output similar to:

Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 2 not upgraded.

How to redirect to an external URL in Angular2?

in newer versions of Angular with window as an any

(window as any).open(someUrl, "_blank");

Ruby Array find_first object?

use array detect method if you wanted to return first value where block returns true

[1,2,3,11,34].detect(&:even?) #=> 2


[1,2,3,11,34].detect{|i| i.even?} #=> 2

If you wanted to return all values where block returns true then use select

[1,2,3,11,34].select(&:even?)  #=> [2, 34]