Programs & Examples On #Xsd2code

Xsd2Code is a CSharp or Visual Basic Business Entity class Generator from XSD schema.

How to search for a string in cell array in MATLAB?

Most shortest code:

strs = {'HA' 'KU' 'LA' 'MA' 'TATA'};
[~,ind]=ismember('KU', strs)

But it returns only first position in strs. If element not found then ind=0.

Convert InputStream to JSONObject

Simple Solution:

JsonElement element = new JsonParser().parse(new InputStreamReader(inputStream));
JSONObject jsonObject = new JSONObject(element.getAsJsonObject().toString());

Select All as default value for Multivalue parameter

This is rather easy to achieve by making a dataset with a text-query like this:

SELECT 'Item1'
SELECT 'Item2'
SELECT 'Item3'
SELECT 'Item4'

The query should return all items that can be selected.

Change link color of the current page with CSS

Use single class name something like class="active" and add it only to current page instead of all pages. If you are at Home something like below:

<ul id="navigation">
<li class="active"><a href="/">Home</a></li>
<li class=""><a href="theatre.php">Theatre</a></li>
<li class=""><a href="programming.php">Programming</a></li> 

and your CSS like{
color: #640200;

How can I simulate a click to an anchor tag?

well, you can very quickly test the click dispatch via jQuery like so


If you're still having problem with click respecting the target, you can always do this

$('#link-id').click( function( event, anchor )
{ anchor.href,, '' );
  return false;

How to make Git "forget" about a file that was tracked but is now in .gitignore?

What didn't work for me

(Under Linux), I wanted to use the posts here suggesting the ls-files --ignored --exclude-standard | xargs git rm -r --cached approach. However, (some of) the files to be removed had an embedded newline/LF/\n in their names. Neither of the solutions:

git ls-files --ignored --exclude-standard | xargs -d"\n" git rm --cached
git ls-files --ignored --exclude-standard | sed 's/.*/"&"/' | xargs git rm -r --cached

cope with this situation (get errors about files not found).

So I offer

git ls-files -z --ignored --exclude-standard | xargs -0 git rm -r --cached
git commit -am "Remove ignored files"

This uses the -z argument to ls-files, and the -0 argument to xargs to cater safely/correctly for "nasty" characters in filenames.

In the manual page git-ls-files(1), it states:

When -z option is not used, TAB, LF, and backslash characters in pathnames are represented as \t, \n, and \\, respectively.

so I think my solution is needed if filenames have any of these characters in them.

How to add checkboxes to JTABLE swing

1) JTable knows JCheckbox with built-in Boolean TableCellRenderers and TableCellEditor by default, then there is contraproductive declare something about that,

2) AbstractTableModel should be useful, where is in the JTable required to reduce/restrict/change nested and inherits methods by default implemented in the DefaultTableModel,

3) consider using DefaultTableModel, (if you are not sure about how to works) instead of AbstractTableModel,


could be generated from simple code:

import javax.swing.*;
import javax.swing.table.*;

public class TableCheckBox extends JFrame {

    private static final long serialVersionUID = 1L;
    private JTable table;

    public TableCheckBox() {
        Object[] columnNames = {"Type", "Company", "Shares", "Price", "Boolean"};
        Object[][] data = {
            {"Buy", "IBM", new Integer(1000), new Double(80.50), false},
            {"Sell", "MicroSoft", new Integer(2000), new Double(6.25), true},
            {"Sell", "Apple", new Integer(3000), new Double(7.35), true},
            {"Buy", "Nortel", new Integer(4000), new Double(20.00), false}
        DefaultTableModel model = new DefaultTableModel(data, columnNames);
        table = new JTable(model) {

            private static final long serialVersionUID = 1L;

            public Class getColumnClass(int column) {
            return getValueAt(0, column).getClass();
            public Class getColumnClass(int column) {
                switch (column) {
                    case 0:
                        return String.class;
                    case 1:
                        return String.class;
                    case 2:
                        return Integer.class;
                    case 3:
                        return Double.class;
                        return Boolean.class;
        JScrollPane scrollPane = new JScrollPane(table);

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            public void run() {
                TableCheckBox frame = new TableCheckBox();
                frame.setLocation(150, 150);

(Excel) Conditional Formatting based on Adjacent Cell Value

You need to take out the $ signs before the row numbers in the formula....and the row number used in the formula should correspond to the first row of data, so if you are applying this to the ("applies to") range $B$2:$B$5 it must be this formula


by using that "relative" version rather than your "absolute" one Excel (implicitly) adjusts the formula for each row in the range, as if you were copying the formula down

Getting the Username from the HKEY_USERS values

By searching for my userid in the registry, I found

HKEY_CURRENT_USER\Volatile Environment\Username

check if a string matches an IP address pattern in python?

You can make it a little faster by compiling it:

expression = re.compile('^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$')
for st in strs:
    if expression.match(st):
       print 'IP!'

Object cannot be cast from DBNull to other types

I'm thinking that your output parameter is coming back with a DBNull value. Add a check for that like this

var outputParam = dataAccCom.GetParameterValue(IDbCmd, "op_Id");
if(!(outputParam is DBNull))
     DataTO.Id = Convert.ToInt64(outputParam);

Converting from Integer, to BigInteger

You can do in this way:

    Integer i = 1;
    new BigInteger("" + i);

What is an "index out of range" exception, and how do I fix it?

Why does this error occur?

Because you tried to access an element in a collection, using a numeric index that exceeds the collection's boundaries.

The first element in a collection is generally located at index 0. The last element is at index n-1, where n is the Size of the collection (the number of elements it contains). If you attempt to use a negative number as an index, or a number that is larger than Size-1, you're going to get an error.

How indexing arrays works

When you declare an array like this:

var array = new int[6]

The first and last elements in the array are

var firstElement = array[0];
var lastElement = array[5];

So when you write:

var element = array[5];

you are retrieving the sixth element in the array, not the fifth one.

Typically, you would loop over an array like this:

for (int index = 0; index < array.Length; index++)

This works, because the loop starts at zero, and ends at Length-1 because index is no longer less than Length.

This, however, will throw an exception:

for (int index = 0; index <= array.Length; index++)

Notice the <= there? index will now be out of range in the last loop iteration, because the loop thinks that Length is a valid index, but it is not.

How other collections work

Lists work the same way, except that you generally use Count instead of Length. They still start at zero, and end at Count - 1.

for (int index = 0; i < list.Count; index++)

However, you can also iterate through a list using foreach, avoiding the whole problem of indexing entirely:

foreach (var element in list)

You cannot index an element that hasn't been added to a collection yet.

var list = new List<string>();
Console.WriteLine(list[3]);  // Throws exception.

LogCat message: The Google Play services resources were not found. Check your project configuration to ensure that the resources are included

I also had the same problem. In starting, it was working fine then, but sometime later I uninstalled my application completely from my device (I was running it on my mobile) and ran it again, and it shows me the same error.

I had all lib and resources included as it was working, but still I was getting this error so I removed all references and lib from my project build, updated google service play to revision 10, uninstalled application completely from the device and then again added all resources and libs and ran it and it started working again.

One thing to note here is while running I am still seeing this error message in my LogCat, but on my device it is working fine now.

Eclipse Intellisense?

d3dave's answer is cool. However theGreenGarbage mentioned an issue about it which I too find rather annoying. So here's one that doesn't immediately suggest something after '=' sign and when typing blank space:


What I did was simply remove the space and '=' chars from the array :)

Alternatively if you want suggestions when typing blank space, but not after '=' sign:

ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz .(!+-*/~,[{@#$%^&

How do I run a bat file in the background from another bat file?

Two years old, but for completeness...

Standard, inline approach: (i.e. behaviour you'd get when using & in Linux)

START /B CMD /C CALL "foo.bat" [args [...]]

Notes: 1. CALL is paired with the .bat file because that where it usually goes.. (i.e. This is just an extension to the CMD /C CALL "foo.bat" form to make it asynchronous. Usually, it's required to correctly get exit codes, but that's a non-issue here.); 2. Double quotes around the .bat file is only needed if the name contains spaces. (The name could be a path in which case there's more likelihood of that.).

If you don't want the output:

START /B CMD /C CALL "foo.bat" [args [...]] >NUL 2>&1

If you want the bat to be run on an independent console: (i.e. another window)

START CMD /C CALL "foo.bat" [args [...]]

If you want the other window to hang around afterwards:

START CMD /K CALL "foo.bat" [args [...]]

Note: This is actually poor form unless you have users that specifically want to use the opened window as a normal console. If you just want the window to stick around in order to see the output, it's better off putting a PAUSE at the end of the bat file. Or even yet, add ^& PAUSE after the command line:

START CMD /C CALL "foo.bat" [args [...]] ^& PAUSE

ImportError: No module named xlsxwriter

Here are some easy way to get you up and running with the XlsxWriter module.The first step is to install the XlsxWriter module.The pip installer is the preferred method for installing Python modules from PyPI, the Python Package Index:

sudo pip install xlsxwriter


Windows users can omit sudo at the start of the command.

Why is NULL undeclared?

Do use NULL. It is just #defined as 0 anyway and it is very useful to semantically distinguish it from the integer 0.

There are problems with using 0 (and hence NULL). For example:

void f(int);
void f(void*);

f(0); // Ambiguous. Calls f(int).

The next version of C++ (C++0x) includes nullptr to fix this.

f(nullptr); // Calls f(void*).

How to install python3 version of package via pip on Ubuntu?

Firstly, you need to install pip for the Python 3 installation that you want. Then you run that pip to install packages for that Python version.

Since you have both pip and python 3 in /usr/bin, I assume they are both installed with a package manager of some sort. That package manager should also have a Python 3 pip. That's the one you should install.

Felix' recommendation of virtualenv is a good one. If you are only testing, or you are doing development, then you shouldn't install the package in the system python. Using virtualenv, or even building your own Pythons for development, is better in those cases.

But if you actually do want to install this package in the system python, installing pip for Python 3 is the way to go.

Determine the size of an InputStream

If you know that your InputStream is a FileInputStream or a ByteArrayInputStream, you can use a little reflection to get at the stream size without reading the entire contents. Here's an example method:

static long getInputLength(InputStream inputStream) {
    try {
        if (inputStream instanceof FilterInputStream) {
            FilterInputStream filtered = (FilterInputStream)inputStream;
            Field field = FilterInputStream.class.getDeclaredField("in");
            InputStream internal = (InputStream) field.get(filtered);
            return getInputLength(internal);
        } else if (inputStream instanceof ByteArrayInputStream) {
            ByteArrayInputStream wrapper = (ByteArrayInputStream)inputStream;
            Field field = ByteArrayInputStream.class.getDeclaredField("buf");
            byte[] buffer = (byte[])field.get(wrapper);
            return buffer.length;
        } else if (inputStream instanceof FileInputStream) {
            FileInputStream fileStream = (FileInputStream)inputStream;
            return fileStream.getChannel().size();
    } catch (NoSuchFieldException | IllegalAccessException | IOException exception) {
        // Ignore all errors and just return -1.
    return -1;

This could be extended to support additional input streams, I am sure.

How to add directory to classpath in an application run profile in IntelliJ IDEA?

You need not specify the classes folder. Intellij should be able to load it. You will get this error if "Project Compiler output" is blank.

Just make sure that below value is set: Project Settings -> Project -> Project Compiler output to your projectDir/out folder

Checking if sys.argv[x] is defined

It's an ordinary Python list. The exception that you would catch for this is IndexError, but you're better off just checking the length instead.

if len(sys.argv) >= 2:
  startingpoint = sys.argv[1]
  startingpoint = 'blah'

Postgresql: password authentication failed for user "postgres"

Answer given is almost correct just missing some pointers which i'll be taking care of in my solution

First make sure your user have a sudo access if not you can use the below command to add your user as sudo user :-

sudo adduser <username> sudo

The change will take effect the next time the user logs in.

i) Now go to sudo vim /etc/postgresql/<your_postgres_version>/main/pg_hba.conf file and look for line that says :

local   all             postgres                                md5 #peer

and comment that. Just below that line there must be a commented line that says:

local   all             postgres                                peer

or for older versions it'll be :-

local   all         postgres                          ident

Uncomment that line.

ii) Now restart the postgres by using any of these commands :-

sudo /etc/init.d/postgresql restart


sudo service postgresql restart

iii) Now you can simply log into postgres using the following command :

sudo -u postgres psql

iv) once you're in you can create any operation you want to in my case i wanted to create a new database you can do the same using below command :

CREATE DATABASE airflow_replica;

Unzip a file with php

you can use prepacked function

function unzip_file($file, $destination){
    // create object
    $zip = new ZipArchive() ;
    // open archive
    if ($zip->open($file) !== TRUE) {
        return false;
    // extract contents to destination directory
    // close archive
        return true;

How to use it.

echo 'zip archive extracted successfully';
  echo 'zip archive extraction failed';

Docker command can't connect to Docker daemon

  1. I also had the same issue. The problem was in sockets allocated to docker-daemon and docker-client.
  2. First, permission was not set for the docker-client on docker.sock You can set it using "sudo usermod -aG docker $USER"
  3. Then check your bash file where the docker-client is running, For me it was on, while docker-daemon was running on unix socket.(It was set in the configuration file of dockerd).
  4. Just comment the bash-line and it'll work fine.
  5. But if you want to make it work on TCP port instead of unix socket, change the configuration file of dockerd and set it on and keep the line in bash as it is if present or set it to

How to convert a string from uppercase to lowercase in Bash?

If you are using bash 4 you can use the following approach:

echo $x  # HELLO

echo $y  # hello

echo $z  # HELLO

Use only one , or ^ to make the first letter lowercase or uppercase.

git push >> fatal: no configured push destination

I have faced this error, Previous I had push in root directory, and now I have push another directory, so I could be remove this error and run below commands.

git add .
git commit -m "some comments"
git push --set-upstream origin master

How to create a timeline with LaTeX?

I have been struggling to find a proper way to create a timeline, which I could finally do with this modification. Usually while creating a timeline the problem was that I could not add a text to explain each date clearly with a longer text. I modified and further utilized @Zoe Gagnon's latex script. Please feel free to see the following:


        % draw horizontal line   
        \draw (-5,0) -- (6,0);
    % draw vertical lines
    \foreach \x in {-5,-4,-3,-2, -1,0,1,2}
    \draw (\x cm,3pt) -- (\x cm,-3pt);
    % draw nodes
    \draw (-5,0) node[below=3pt] {$ 0 $} node[above=3pt] {$  $};
    \draw (-4,0) node[below=3pt] {$ 1 $} node[above=3pt] {$\begin{turn}{45}
            All individuals vote
    \draw (-3,0) node[below=3pt] {$ 2 $} node[above=3pt] {$\begin{turn}{45} 
        Policy vector decided
    \draw (-2,0) node[below=3pt] {$ 3 $} node[above=3pt] {$\begin{turn}{45}  Becoming a bureaucrat \end{turn} $};
    \draw (-1,0) node[below=3pt] {$ 4 $} node[above=3pt] {$\begin{turn}{45} Bureaucrats' effort choice \end{turn}$};
    \draw (0,0) node[below=3pt] {$ 5 $} node[above=3pt] {$\begin{turn}{45} Tax evasion decision made \end{turn}$};
    \draw (1,0) node[below=3pt] {$  6$} node[above=3pt] {$\begin{turn}{45} $p(x_{t})$ tax evaders caught \end{turn}$};
    \draw (2,0) node[below=3pt] {$ 7 $} node[above=3pt] {$\begin{turn}{45} $q_{t}$ shirking bureaucrats \end{turn}$};
            \draw (3,0) node[below=3pt] {$ $} node[above=3pt] {$\begin{turn}{45} Public service provided  \end{turn}   $};

Longer texts are not allowed, unfortunately. It will look like this:

visual depiction of the timeline above

Reload a DIV without reloading the whole page

Your html is not updated every 15 seconds. The cause could be browser caching. Add Math.random() to avoid browser caching, and it's better to wait until the DOM is fully loaded as pointed out by @shadow. But I think the main cause is the caching

<script type="text/javascript" src="" />
<script type="text/javascript">
    var auto_refresh = setInterval(
    function ()
       $('.View').load('Small.php?' + Math.random()).fadeIn("slow");
    }, 15000); // refresh every 15000 milliseconds

Echo a blank (empty) line to the console from a Windows batch file

Note: Though my original answer attracted several upvotes, I decided that I could do much better. You can find my original (simplistic and misguided) answer in the edit history.

If Microsoft had the intent of providing a means of outputting a blank line from cmd.exe, Microsoft surely would have documented such a simple operation. It is this omission that motivated me to ask this question.

So, because a means for outputting a blank line from cmd.exe is not documented, arguably one should consider any suggestion for how to accomplish this to be a hack. That means that there is no known method for outputting a blank line from cmd.exe that is guaranteed to work (or work efficiently) in all situations.

With that in mind, here is a discussion of methods that have been recommended for outputting a blank line from cmd.exe. All recommendations are based on variations of the echo command.


While this will work in many if not most situations, it should be avoided because it is slower than its alternatives and actually can fail (see here, here, and here). Specifically, cmd.exe first searches for a file named echo and tries to start it. If a file named echo happens to exist in the current working directory, echo. will fail with:

'echo.' is not recognized as an internal or external command,
operable program or batch file.


At the end of this answer, the author argues that these commands can be slow, for instance if they are executed from a network drive location. A specific reason for the potential slowness is not given. But one can infer that it may have something to do with accessing the file system. (Perhaps because : and \ have special meaning in a Windows file system path?)

However, some may consider these to be safe options since : and \ cannot appear in a file name. For that or another reason, echo: is recommended by here.


This lengthy discussion includes what I believe to be all of these. Several of these options are recommended in this SO answer as well. Within the cited discussion, this post ends with what appears to be a recommendation for echo( and echo:.

My question at the top of this page does not specify a version of Windows. My experimentation on Windows 10 indicates that all of these produce a blank line, regardless of whether files named echo, echo+, echo,, ..., echo] exist in the current working directory. (Note that my question predates the release of Windows 10. So I concede the possibility that older versions of Windows may behave differently.)

In this answer, @jeb asserts that echo( always works. To me, @jeb's answer implies that other options are less reliable but does not provide any detail as to why that might be. Note that @jeb contributed much valuable content to other references I have cited in this answer.

Conclusion: Do not use echo.. Of the many other options I encountered in the sources I have cited, the support for these two appears most authoritative:


But I have not found any strong evidence that the use of either of these will always be trouble-free.

Example Usage:

@echo off
echo Here is the first line.
echo There is a blank line above this line.

Expected output:

Here is the first line.

There is a blank line above this line.

How to get the latest file in a folder?

A much faster method on windows (0.05s), call a bat script that does this:


@echo off
for /f %%i in ('dir \\directory\in\question /b/a-d/od/t:c') do set LAST=%%i

where \\directory\in\question is the directory you want to investigate.

from subprocess import Popen, PIPE
p = Popen("get_latest.bat", shell=True, stdout=PIPE,)
stdout, stderr = p.communicate()
print(stdout, stderr)

if it finds a file stdout is the path and stderr is None.

Use stdout.decode("utf-8").rstrip() to get the usable string representation of the file name.

How to rotate a 3D object on axis three.js?

I needed the rotateAroundWorldAxis function but the above code doesn't work with the newest release (r52). It looks like getRotationFromMatrix() was replaced by setEulerFromRotationMatrix()

function rotateAroundWorldAxis( object, axis, radians ) {

    var rotationMatrix = new THREE.Matrix4();

    rotationMatrix.makeRotationAxis( axis.normalize(), radians );
    rotationMatrix.multiplySelf( object.matrix );                       // pre-multiply
    object.matrix = rotationMatrix;
    object.rotation.setEulerFromRotationMatrix( object.matrix );

Elegant solution for line-breaks (PHP)

\n didn't work for me. the \n appear in the bodytext of the email I was sending.. this is how I resolved it.

str_pad($input, 990); //so that the spaces will pad out to the 990 cut off.

Javascript reduce() on Object

If handled as an array is much easier

Return the total amount of fruits:

let fruits = [{ name: 'banana', id: 0, quantity: 9 }, { name: 'strawberry', id: 1, quantity: 1 }, { name: 'kiwi', id: 2, quantity: 2 }, { name: 'apple', id: 3, quantity: 4 }]

let total = fruits.reduce((sum, f) => sum + f.quantity, 0);

Check, using jQuery, if an element is 'display:none' or block on click

$("element").filter(function() { return $(this).css("display") == "none" });

How can I generate a tsconfig.json file?

$ npm run tsc -- --init
This worked for the below package.json

  "devDependencies": {
    "@types/jasmine": "^3.6.2",
    "@types/node": "^14.14.19",
    "jasmine": "^3.6.3",
    "protractor": "^7.0.0",
    "typescript": "^4.1.3"

RSA encryption and decryption in Python

Here is my implementation for python 3 and pycrypto

from Crypto.PublicKey import RSA
key = RSA.generate(4096)
f = open('/home/john/Desktop/my_rsa_public.pem', 'wb')
f = open('/home/john/Desktop/my_rsa_private.pem', 'wb')

f = open('/home/john/Desktop/my_rsa_public.pem', 'rb')
f1 = open('/home/john/Desktop/my_rsa_private.pem', 'rb')
key = RSA.importKey(
key1 = RSA.importKey(

x = key.encrypt(b"dddddd",32)

z = key1.decrypt(x)

How to export data to an excel file using PHPExcel

I currently use this function in my project after a series of googling to download excel file from sql statement

    // $sql = sql query e.g "select * from mytablename"
    // $filename = name of the file to download 
        function queryToExcel($sql, $fileName = 'name.xlsx') {
                // initialise excel column name
                // currently limited to queries with less than 27 columns
        $columnArray = array("A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z");
                // Execute the database query
                $result =  mysql_query($sql) or die(mysql_error());

                // Instantiate a new PHPExcel object
                $objPHPExcel = new PHPExcel();
                // Set the active Excel worksheet to sheet 0
                // Initialise the Excel row number
                $rowCount = 1;
    // fetch result set column information
                $finfo = mysqli_fetch_fields($result);
// initialise columnlenght counter                
$columnlenght = 0;
                foreach ($finfo as $val) {
// set column header values                   
  $objPHPExcel->getActiveSheet()->SetCellValue($columnArray[$columnlenght++] . $rowCount, $val->name);
// make the column headers bold

                // Iterate through each result from the SQL query in turn
                // We fetch each database result row into $row in turn

                while ($row = mysqli_fetch_array($result, MYSQL_NUM)) {
                    for ($i = 0; $i < $columnLenght; $i++) {
                        $objPHPExcel->getActiveSheet()->SetCellValue($columnArray[$i] . $rowCount, $row[$i]);
// set header information to force download
                header('Content-type: application/');
                header('Content-Disposition: attachment; filename="' . $fileName . '"');
                // Instantiate a Writer to create an OfficeOpenXML Excel .xlsx file        
                // Write the Excel file to filename some_excel_file.xlsx in the current directory                
                $objWriter = new PHPExcel_Writer_Excel2007($objPHPExcel); 
                // Write the Excel file to filename some_excel_file.xlsx in the current directory

SQL Server Pivot Table with multiple column aggregates

I used your own pivot as a nested query and came to this result:

  SUM(ISNULL([Australia], 0)) AS [Transactions Australia],
  SUM(CASE WHEN [Australia] IS NOT NULL THEN [TotalAmount] ELSE 0 END) AS [Amount Australia],
  SUM(ISNULL([Austria], 0)) AS [Transactions Austria],
  SUM(CASE WHEN [Austria] IS NOT NULL THEN [TotalAmount] ELSE 0 END) AS [Amount Austria]
  select * 
  from  mytransactions
  pivot (sum (totalcount) for country in ([Australia], [Austria])) as pvt
) AS [sub]
  [sub].[numericmonth] ASC

Here is the Fiddle.

How to prevent column break within an element?

Firefox now supports this:

page-break-inside: avoid;

This solves the problem of elements breaking across columns.

React Hook Warnings for async function in useEffect: useEffect function must return a cleanup function or nothing


const MyFunctionnalComponent: React.FC = props => {_x000D_
  useEffect(() => {_x000D_
    // Using an IIFE_x000D_
    (async function anyNameFunction() {_x000D_
      await loadContent();_x000D_
  }, []);_x000D_
  return <div></div>;_x000D_

How to check if number is divisible by a certain number?

n % x == 0

Means that n can be divided by x. So... for instance, in your case:

boolean isDivisibleBy20 = number % 20 == 0;

Also, if you want to check whether a number is even or odd (whether it is divisible by 2 or not), you can use a bitwise operator:

boolean even = (number & 1) == 0;
boolean odd  = (number & 1) != 0;

How to use ClassLoader.getResources() correctly?

MRalwasser, I'd give you a hint, cast the URL.getConnection() to JarURLConnection. Then use JarURLConnection.getJarFile() and voila! You have the JarFile and you are free to access the resources inside.

The rest I leave to you.

Hope this helps!

Open mvc view in new window from controller

You can use as follows

public ActionResult NewWindow()
    return Content("<script>'{url}','_blank')</script>");

Rewrite URL after redirecting 404 error htaccess

Try this in your .htaccess:


ErrorDocument 404
ErrorDocument 500
# or map them to one error document:
# ErrorDocument 404 /pages/errors/error_redirect.php
# ErrorDocument 500 /pages/errors/error_redirect.php

RewriteEngine On
RewriteBase /

RewriteCond %{REQUEST_URI} ^/404/$
RewriteRule ^(.*)$ /pages/errors/404.php [L]

RewriteCond %{REQUEST_URI} ^/500/$
RewriteRule ^(.*)$ /pages/errors/500.php [L]

# or map them to one error document:
#RewriteCond %{REQUEST_URI} ^/404/$ [OR]
#RewriteCond %{REQUEST_URI} ^/500/$
#RewriteRule ^(.*)$ /pages/errors/error_redirect.php [L]

The ErrorDocument redirects all 404s to a specific URL, all 500s to another url (replace with your domain).

The Rewrite rules map that URL to your actual 404.php script. The RewriteCond regular expressions can be made more generic if you want, but I think you have to explicitly define all ErrorDocument codes you want to override.

Local Redirect:

Change .htaccess ErrorDocument to a file that exists (must exist, or you'll get an error):

ErrorDocument 404 /pages/errors/404_redirect.php


   header('Location: /404/');

Redirect based on error number

Looks like you'll need to specify an ErrorDocument line in .htaccess for every error you want to redirect (see: Apache ErrorDocument and Apache Custom Error). The .htaccess example above has multiple examples in it. You can use the following as the generic redirect script to replace 404_redirect.php above.


   $error_url = $_SERVER["REDIRECT_STATUS"] . '/';
   $error_path = $error_url . '.php';

   if ( ! file_exists($error_path)) {
      // this is the default error if a specific error page is not found
      $error_url = '404/';

   header('Location: ' . $error_url);

MySQL my.ini location


Open a Windows command shell and type: echo %PROGRAMDATA%. On Windows Vista this results in: C:\ProgramData.

According to, the first location MySQL will look under is in %PROGRAMDATA%\MySQL\MySQL Server 5.6\my.ini. In your Windows shell if you do ls "%PROGRAMDATA%\MySQL\MySQL Server 5.6\my.ini", you will see that the file is there.

Unlike most suggestions you will find in Stackoverflow and around the web, putting the file in C:\Program Files\MySQL\MySQL Server 5.6\my.ini WILL NOT WORK. Neither will C:\Program Files (x86)\MySQL\MySQL Server 5.1. The reason being quoted on the MySQL link posted above:

On Windows, MySQL programs read startup options from the following files, in the specified order (top items are used first).

The 5.6 MSI installer does create a my.ini in the highest priority location, meaning no other file will ever be found/used, except for the one created by the installer.

The solution accepted above will not work for 5.6 MSI-based installs.

How to return a list of keys from a Hash Map?

List<String> yourList = new ArrayList<>(map.keySet());

This is will do just fine.

How to do a subquery in LINQ?

This is how I've been doing subqueries in LINQ, I think this should get what you want. You can replace the explicit CompanyRoleId == 2... with another subquery for the different roles you want or join it as well.

from u in Users
join c in (
    from crt in CompanyRolesToUsers
    where CompanyRoleId == 2
    || CompanyRoleId == 3
    || CompanyRoleId == 4) on u.UserId equals c.UserId
where u.lastname.Contains("fra")
select u;

How can I find out if I have Xcode commandline tools installed?

I was able to find my version of Xcode on maxOS Sierra using this command:

pkgutil | grep version

as per this answer.

Check key exist in python dict

Use the in keyword.

if 'apples' in d:
    if d['apples'] == 20:
        print('20 apples')
        print('Not 20 apples')

If you want to get the value only if the key exists (and avoid an exception trying to get it if it doesn't), then you can use the get function from a dictionary, passing an optional default value as the second argument (if you don't pass it it returns None instead):

if d.get('apples', 0) == 20:
    print('20 apples.')
    print('Not 20 apples.')

How to Get XML Node from XDocument

The .Elements operation returns a LIST of XElements - but what you really want is a SINGLE element. Add this:

XElement Contacts = (from xml2 in XMLDoc.Elements("Contacts").Elements("Node")
                    where xml2.Element("ID").Value == variable
                    select xml2).FirstOrDefault();

This way, you tell LINQ to give you the first (or NULL, if none are there) from that LIST of XElements you're selecting.


Change Background color (css property) using Jquery

   $(this).css({"backgroundColor" : "blue"});

Xcode - How to fix 'NSUnknownKeyException', reason: … this class is not key value coding-compliant for the key X" error?

I had a similar problem for a project that has two targets (with their own MainWindow XIB). The fundamental issue that caused this error for me was that the UIViewController class wasn't included in the second project's resource list. I.e. interface builder allowed me to specify it in MainWindow.xib, but at runtime the system couldn't locate the class.

I.e. cmd-click on the UIViewController class in question and double-check that it's included in the 'Targets' tab.

Using Google Text-To-Speech in Javascript

The below JavaScript code sends "text" to be spoken/converted to mp3 audio to google cloud text-to-speech API and gets mp3 audio content as response back.

 var text-to-speech = function(state) {
    const url = ''
    const data = {
         'text':'Android is a mobile operating system developed by Google, based on the Linux kernel and designed primarily for touchscreen mobile devices such as smartphones and tablets.'
     const otherparam={
           "content-type":"application/json; charset=UTF-8"
    .then(data=>{return data.json()})
    .then(res=>{console.log(res.audioContent); })

How to create file execute mode permissions in Git on Windows?

If the files already have the +x flag set, git update-index --chmod=+x does nothing and git thinks there's nothing to commit, even though the flag isn't being saved into the repo.

You must first remove the flag, run the git command, then put the flag back:

chmod -x <file>
git update-index --chmod=+x <file>
chmod +x <file>

then git sees a change and will allow you to commit the change.

What is Robocopy's "restartable" option?

Restartable mode (/Z) has to do with a partially-copied file. With this option, should the copy be interrupted while any particular file is partially copied, the next execution of robocopy can pick up where it left off rather than re-copying the entire file.

That option could be useful when copying very large files over a potentially unstable connection.

Backup mode (/B) has to do with how robocopy reads files from the source system. It allows the copying of files on which you might otherwise get an access denied error on either the file itself or while trying to copy the file's attributes/permissions. You do need to be running in an Administrator context or otherwise have backup rights to use this flag.

What does .shape[] do in "for i in range(Y.shape[0])"?

shape is a tuple that gives you an indication of the number of dimensions in the array. So in your case, since the index value of Y.shape[0] is 0, your are working along the first dimension of your array.


 An array has a shape given by the number of elements along each axis:
 >>> a = floor(10*random.random((3,4)))

 >>> a
 array([[ 7.,  5.,  9.,  3.],
        [ 7.,  2.,  7.,  8.],
        [ 6.,  8.,  3.,  2.]])

 >>> a.shape
 (3, 4)

and has some more examples.

Regex match everything after question mark?

Check out this site: Basically the site allows you to enter some example text (what you would be looking for on your site) and then as you build the regular expression it will highlight what is being matched in real time.

Ignore Typescript Errors "property does not exist on value of type"

In my particular project I couldn't get it to work, and used declare var $;. Not a clean/recommended solution, it doesnt recognise the JQuery variables, but I had no errors after using that (and had to for my automatic builds to succeed).

I want to execute shell commands from Maven's pom.xml

Thanks! Tomer Ben David. it helped me. as I am doing pip install in demo folder as you mentioned npm install


IEnumerable vs List - What to Use? How do they work?

A class that implement IEnumerable allows you to use the foreach syntax.

Basically it has a method to get the next item in the collection. It doesn't need the whole collection to be in memory and doesn't know how many items are in it, foreach just keeps getting the next item until it runs out.

This can be very useful in certain circumstances, for instance in a massive database table you don't want to copy the entire thing into memory before you start processing the rows.

Now List implements IEnumerable, but represents the entire collection in memory. If you have an IEnumerable and you call .ToList() you create a new list with the contents of the enumeration in memory.

Your linq expression returns an enumeration, and by default the expression executes when you iterate through using the foreach. An IEnumerable linq statement executes when you iterate the foreach, but you can force it to iterate sooner using .ToList().

Here's what I mean:

var things = 
    from item in BigDatabaseCall()
    where ....
    select item;

// this will iterate through the entire linq statement:
int count = things.Count();

// this will stop after iterating the first one, but will execute the linq again
bool hasAnyRecs = things.Any();

// this will execute the linq statement *again*
foreach( var thing in things ) ...

// this will copy the results to a list in memory
var list = things.ToList()

// this won't iterate through again, the list knows how many items are in it
int count2 = list.Count();

// this won't execute the linq statement - we have it copied to the list
foreach( var thing in list ) ...

How to enter special characters like "&" in oracle database?


What does Statement.setFetchSize(nSize) method really do in SQL Server JDBC driver?

I had the exact same problem in a project. The issue is that even though the fetch size might be small enough, the JDBCTemplate reads all the result of your query and maps it out in a huge list which might blow your memory. I ended up extending NamedParameterJdbcTemplate to create a function which returns a Stream of Object. That Stream is based on the ResultSet normally returned by JDBC but will pull data from the ResultSet only as the Stream requires it. This will work if you don't keep a reference of all the Object this Stream spits. I did inspire myself a lot on the implementation of org.springframework.jdbc.core.JdbcTemplate#execute(org.springframework.jdbc.core.ConnectionCallback). The only real difference has to do with what to do with the ResultSet. I ended up writing this function to wrap up the ResultSet:

private <T> Stream<T> wrapIntoStream(ResultSet rs, RowMapper<T> mapper) {
    CustomSpliterator<T> spliterator = new CustomSpliterator<T>(rs, mapper, Long.MAX_VALUE, NON-NULL | IMMUTABLE | ORDERED);
    Stream<T> stream =, false);
    return stream;
private static class CustomSpliterator<T> extends Spliterators.AbstractSpliterator<T> {
    // won't put code for constructor or properties here
    // the idea is to pull for the ResultSet and set into the Stream
    public boolean tryAdvance(Consumer<? super T> action) {
        try {
            // you can add some logic to close the stream/Resultset automatically
            if( {
                T mapped = mapper.mapRow(rs, rowNumber++);
                return true;
            } else {
                return false;
        } catch (SQLException) {
            // do something with this Exception

you can add some logic to make that Stream "auto closable", otherwise don't forget to close it when you are done.

Picking a random element from a set

Can't you just get the size/length of the set/array, generate a random number between 0 and the size/length, then call the element whose index matches that number? HashSet has a .size() method, I'm pretty sure.

In psuedocode -

function randFromSet(target){
 var targetLength:uint = target.length()
 var randomIndex:uint = random(0,targetLength);
 return target[randomIndex];

How do I read any request header in PHP

IF: you only need a single header, instead of all headers, the quickest method is:

// Replace XXXXXX_XXXX with the name of the header you need in UPPERCASE (and with '-' replaced by '_')
$headerStringValue = $_SERVER['HTTP_XXXXXX_XXXX'];

ELSE IF: you run PHP as an Apache module or, as of PHP 5.4, using FastCGI (simple method):


$headers = apache_request_headers();

foreach ($headers as $header => $value) {
    echo "$header: $value <br />\n";

ELSE: In any other case, you can use (userland implementation):

function getRequestHeaders() {
    $headers = array();
    foreach($_SERVER as $key => $value) {
        if (substr($key, 0, 5) <> 'HTTP_') {
        $header = str_replace(' ', '-', ucwords(str_replace('_', ' ', strtolower(substr($key, 5)))));
        $headers[$header] = $value;
    return $headers;

$headers = getRequestHeaders();

foreach ($headers as $header => $value) {
    echo "$header: $value <br />\n";

See Also:
getallheaders() - (PHP >= 5.4) cross platform edition Alias of apache_request_headers() apache_response_headers() - Fetch all HTTP response headers.
headers_list() - Fetch a list of headers to be sent.

PHP Echo text Color

this works for me every time try this.

echo "<font color='blue'>".$myvariable."</font>";

since font is not supported in html5 you can do this

echo "<p class="variablecolor">".$myvariable."</p>";

then in css do

color: blue;}

Remove trailing zeros from decimal in SQL Server

The easiest way is to CAST the value as FLOAT and then to a string data type.


Converting XML to JSON using Python?

You may want to have a look at This project starts off with an XML to JSON conversion of a large library of XML files. There was much research done in the conversion, and the most simple intuitive XML -> JSON mapping was produced (it is described early in the document). In summary, convert everything to a JSON object, and put repeating blocks as a list of objects.

objects meaning key/value pairs (dictionary in Python, hashmap in Java, object in JavaScript)

There is no mapping back to XML to get an identical document, the reason is, it is unknown whether a key/value pair was an attribute or an <key>value</key>, therefore that information is lost.

If you ask me, attributes are a hack to start; then again they worked well for HTML.

How can we generate getters and setters in Visual Studio?

First get Extension just press (Ctrl + Shift + X) and install getter setter ....

After this, just select your variable and right click. Go to Command palette...

And type getter ... It will suggest generate get and set methods. Click on this...

Django -- Template tag in {% if %} block

You shouldn't use the double-bracket {{ }} syntax within if or ifequal statements, you can simply access the variable there like you would in normal python:

{% if title == source %}
{% endif %}

Java: Date from unix timestamp

Date d = new Date(i * 1000 + TimeZone.getDefault().getRawOffset());

How can I convert a timestamp from yyyy-MM-ddThh:mm:ss:SSSZ format to MM/dd/yyyy hh:mm:ss.SSS format? From ISO8601 to UTC

Hope this Helps:

public String getSystemTimeInBelowFormat() {
    String timestamp = new SimpleDateFormat("yyyy-mm-dd 'T' HH:MM:SS.mmm-HH:SS").format(new Date());
    return timestamp;

How to install easy_install in Python 2.7.1 on Windows 7

I know this isn't a direct answer to your question but it does offer one solution to your problem. Python 2.7.9 includes PIP and SetupTools, if you update to this version you will have one solution to your problem.

How would I find the second largest salary from the employee table?

Try this:

SELECT max(salary)
FROM emptable
WHERE salary < (SELECT max(salary)
                FROM emptable);

How to use concerns in Rails 4

This post helped me understand concerns.

# app/models/trader.rb
class Trader
  include Shared::Schedule

# app/models/concerns/shared/schedule.rb
module Shared::Schedule
  extend ActiveSupport::Concern

Using Jasmine to spy on a function without an object

If you are defining your function:

function test() {};

Then, this is equivalent to:

window.test = function() {}  /* (in the browser) */

So spyOn(window, 'test') should work.

If that is not, you should also be able to:

test = jasmine.createSpy();

If none of those are working, something else is going on with your setup.

I don't think your fakeElement technique works because of what is going on behind the scenes. The original globalMethod still points to the same code. What spying does is proxy it, but only in the context of an object. If you can get your test code to call through the fakeElement it would work, but then you'd be able to give up global fns.

HTML SELECT - Change selected option by VALUE using JavaScript

If you are using jQuery:


Automatic creation date for Django model form objects?

You can use the auto_now and auto_now_add options for updated_at and created_at respectively.

class MyModel(models.Model):
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

What is a "method" in Python?

If you think of an object as being similar to a noun, then a method is similar to a verb. Use a method right after an object (i.e. a string or a list) to apply a method's action to it.

How can I find whitespace in a String?

Use this code, was better solution for me.

public static boolean containsWhiteSpace(String line){
    boolean space= false; 
    if(line != null){

        for(int i = 0; i < line.length(); i++){

            if(line.charAt(i) == ' '){
            space= true;

    return space;

How to determine the IP address of a Solaris system

The following worked pretty well for me:

ping -s my_host_name

Oracle date function for the previous month

I believe this would also work:

select count(distinct switch_id)   
  from [email protected]  
   dealer_name =  'XXXX'    
   and (creation_date BETWEEN add_months(trunc(sysdate,'mm'),-1) and  trunc(sysdate, 'mm'))

It has the advantage of using BETWEEN which is the way the OP used his date selection criteria.

c++ boost split string

The problem is somewhere else in your code, because this works:

string line("test\ttest2\ttest3");
vector<string> strs;

cout << "* size of the vector: " << strs.size() << endl;    
for (size_t i = 0; i < strs.size(); i++)
    cout << strs[i] << endl;

and testing your approach, which uses a vector iterator also works:

string line("test\ttest2\ttest3");
vector<string> strs;

cout << "* size of the vector: " << strs.size() << endl;
for (vector<string>::iterator it = strs.begin(); it != strs.end(); ++it)
    cout << *it << endl;

Again, your problem is somewhere else. Maybe what you think is a \t character on the string, isn't. I would fill the code with debugs, starting by monitoring the insertions on the vector to make sure everything is being inserted the way its supposed to be.


* size of the vector: 3

Eclipse: How do I add the javax.servlet package to a project?

Go to


include JAR


For me it worked

How do I debug "Error: spawn ENOENT" on node.js?

Are you changing the env option?

Then look at this answer.

I was trying to spawn a node process and TIL that you should spread the existing environment variables when you spawn else you'll loose the PATH environment variable and possibly other important ones.

This was the fix for me:

const nodeProcess = spawn('node', ['--help'], {
  env: {
    // by default, spawn uses `process.env` for the value of `env`
    // you can _add_ to this behavior, by spreading `process.env`

Match line break with regular expression

You could search for:

<li><a href="#">[^\n]+

And replace with:


Where $0 is the whole match. The exact semantics will depend on the language are you using though.

WARNING: You should avoid parsing HTML with regex. Here's why.

CASE (Contains) rather than equal statement

CASE WHEN ', ' + dbo.Table.Column +',' LIKE '%, lactulose,%' 
  THEN 'BP Medication' ELSE '' END AS [BP Medication]

The leading ', ' and trailing ',' are added so that you can handle the match regardless of where it is in the string (first entry, last entry, or anywhere in between).

That said, why are you storing data you want to search on as a comma-separated string? This violates all kinds of forms and best practices. You should consider normalizing your schema.

In addition: don't use 'single quotes' as identifier delimiters; this syntax is deprecated. Use [square brackets] (preferred) or "double quotes" if you must. See "string literals as column aliases" here:

EDIT If you have multiple values, you can do this (you can't short-hand this with the other CASE syntax variant or by using something like IN()):

  WHEN ', ' + dbo.Table.Column +',' LIKE '%, lactulose,%' 
  WHEN ', ' + dbo.Table.Column +',' LIKE '%, amlodipine,%' 
  THEN 'BP Medication' ELSE '' END AS [BP Medication]

If you have more values, it might be worthwhile to use a split function, e.g.

USE tempdb;

       ( SELECT Item = x.i.value('(./text())[1]', 'nvarchar(max)')
         FROM ( SELECT [XML] = CONVERT(XML, '<i>'
         + REPLACE(@List,',', '</i><i>') + '</i>').query('.')
           ) AS a CROSS APPLY [XML].nodes('i') AS x(i) ) AS y

CREATE TABLE dbo.[Table](ID INT, [Column] VARCHAR(255));

(1,'lactulose, Lasix (furosemide), oxazepam, propranolol, rabeprazole, sertraline,'),
(2,'lactulite, Lasix (furosemide), lactulose, propranolol, rabeprazole, sertraline,'),
(3,'lactulite, Lasix (furosemide), oxazepam, propranolol, rabeprazole, sertraline,'),
(4,'lactulite, Lasix (furosemide), lactulose, amlodipine, rabeprazole, sertraline,');

  FROM dbo.[Table] AS t
  INNER JOIN dbo.SplitStrings('lactulose,amlodipine') AS s
  ON ', ' + t.[Column] + ',' LIKE '%, ' + s.Item + ',%'



How to check if a specified key exists in a given S3 bucket using Java

Alternatively you can use Minio-Java client library, its Open Source and compatible with AWS S3 API.

You can use Minio-Java examples for the same.

import io.minio.MinioClient;
import io.minio.errors.MinioException;


import org.xmlpull.v1.XmlPullParserException;

public class GetObject {
  public static void main(String[] args)
    throws NoSuchAlgorithmException, IOException, InvalidKeyException, XmlPullParserException, MinioException {
    // Note: YOUR-ACCESSKEYID, YOUR-SECRETACCESSKEY and my-bucketname are
    // dummy values, please replace them with original values.
    // Set s3 endpoint, region is calculated automatically
    MinioClient s3Client = new MinioClient("", "YOUR-ACCESSKEYID", "YOUR-SECRETACCESSKEY");
    InputStream stream = s3Client.getObject("my-bucketname", "my-objectname");

    byte[] buf = new byte[16384];
    int bytesRead;
    while ((bytesRead =, 0, buf.length)) >= 0) {
      System.out.println(new String(buf, 0, bytesRead));


I hope it helps.

Disclaimer : I work for Minio

Div side by side without float

I am currently working on this, and i have already a number of solutions. It is nice to have a high quality site, that i can use also for my convenience. Because if you do not write these things down, you will eventually forget some parts. And i can also recommend writing some basic's down if you are starting any kind of new programming/design.

So if the float functions are causing problems there is a couple of options you can try.

One is modify the div alignment in the div tag it self like so <div class="kosher" align=left> If this does not suit you then there is another option with margin like so.

.leftdiv {
    display: inline-block;
    width: 40%;
    float: left;
.rightdiv {
    display: block;
    margin-right: 20px;
    margin-left: 45%;

Don't forget to remove the <div align=left>.

Correct way of looping through C++ arrays

string texts[] = {"Apple", "Banana", "Orange"};
for( unsigned int a = 0; a < sizeof(texts); a = a + 1 )
    cout << "value of a: " << texts[a] << endl;

Nope. Totally a wrong way of iterating through an array. sizeof(texts) is not equal to the number of elements in the array!

The modern, C++11 ways would be to:

  • use std::array if you want an array whose size is known at compile-time; or
  • use std::vector if its size depends on runtime

Then use range-for when iterating.

#include <iostream>
#include <array>

int main() {
    std::array<std::string, 3> texts = {"Apple", "Banana", "Orange"};
    // ^ An array of 3 elements with the type std::string

    for(const auto& text : texts) {   // Range-for!
        std::cout << text << std::endl;

Live example

You may ask, how is std::array better than the ol' C array? The answer is that it has the additional safety and features of other standard library containers, mostly closely resembling std::vector. Further, The answer is that it doesn't have the quirks of decaying to pointers and thus losing type information, which, once you lose the original array type, you can't use range-for or std::begin/end on it.

changing color of h2

If you absolutely must use HTML to give your text color, you have to use the (deprecated) <font>-tag:

<h2><font color="#006699">Process Report</font></h2>

But otherwise, I strongly recommend you to do as rekire said: use CSS.

Best Practice to Organize Javascript Library & CSS Folder Structure

          bootstrap/--------------Libraries can have js/css/images------------
     common/--------------------common section will have application level resources             


This is how I organized my application's static resources.

How to check if a symlink exists

-L returns true if the "file" exists and is a symbolic link (the linked file may or may not exist). You want -f (returns true if file exists and is a regular file) or maybe just -e (returns true if file exists regardless of type).

According to the GNU manpage, -h is identical to -L, but according to the BSD manpage, it should not be used:

-h file True if file exists and is a symbolic link. This operator is retained for compatibility with previous versions of this program. Do not rely on its existence; use -L instead.

How to avoid installing "Unlimited Strength" JCE policy files when deploying an application?

You could use method

javax.crypto.Cipher.getMaxAllowedKeyLength(String transformation)

to test the available key length, use that and inform the user about what is going on. Something stating that your application is falling back to 128 bit keys due to the policy files not being installed, for example. Security conscious users will install the policy files, others will continue using weaker keys.

Good tool for testing socket connections?

I would go with netcat too , but since you can't use it , here is an alternative : netcat :). You can find netcat implemented in three languages ( python/ruby/perl ) . All you need to do is install the interpreters for the language you choose . Surely , that won't be viewed as a hacking tool .

Here are the links :

Perl implementation

Python implementation

Ruby Implementation

When correctly use Task.Run and when just async-await

One issue with your ContentLoader is that internally it operates sequentially. A better pattern is to parallelize the work and then sychronize at the end, so we get

public class PageViewModel : IHandle<SomeMessage>

   public async void Handle(SomeMessage message)

      // makes UI very laggy, but still not dead
      await this.contentLoader.LoadContentAsync(); 


public class ContentLoader 
    public async Task LoadContentAsync()
        var tasks = new List<Task>();

        await Task.WhenAll(tasks).ConfigureAwait(false);

Obviously, this doesn't work if any of the tasks require data from other earlier tasks, but should give you better overall throughput for most scenarios.

grep --ignore-case --only

This is a known bug on the initial 2.5.1, and has been fixed in early 2007 (Redhat 2.5.1-5) according to the bug reports. Unfortunately Apple is still using 2.5.1 even on Mac OS X 10.7.2.

You could get a newer version via Homebrew (3.0) or MacPorts (2.26) or fink (3.0-1).

Edit: Apparently it has been fixed on OS X 10.11 (or maybe earlier), even though the grep version reported is still 2.5.1.

When and where to use GetType() or typeof()?

typeof is applied to a name of a type or generic type parameter known at compile time (given as identifier, not as string). GetType is called on an object at runtime. In both cases the result is an object of the type System.Type containing meta-information on a type.

Example where compile-time and run-time types are equal

string s = "hello";

Type t1 = typeof(string);
Type t2 = s.GetType();

t1 == t2 ==> true

Example where compile-time and run-time types are different

object obj = "hello";

Type t1 = typeof(object); // ==> object
Type t2 = obj.GetType();  // ==> string!

t1 == t2 ==> false

i.e., the compile time type (static type) of the variable obj is not the same as the runtime type of the object referenced by obj.

Testing types

If, however, you only want to know whether mycontrol is a TextBox then you can simply test

if (mycontrol is TextBox)

Note that this is not completely equivalent to

if (mycontrol.GetType() == typeof(TextBox))    

because mycontrol could have a type that is derived from TextBox. In that case the first comparison yields true and the second false! The first and easier variant is OK in most cases, since a control derived from TextBox inherits everything that TextBox has, probably adds more to it and is therefore assignment compatible to TextBox.

public class MySpecializedTextBox : TextBox

MySpecializedTextBox specialized = new MySpecializedTextBox();
if (specialized is TextBox)       ==> true

if (specialized.GetType() == typeof(TextBox))        ==> false


If you have the following test followed by a cast and T is nullable ...

if (obj is T) {
    T x = (T)obj; // The casting tests, whether obj is T again!

... you can change it to ...

T x = obj as T;
if (x != null) {

Testing whether a value is of a given type and casting (which involves this same test again) can both be time consuming for long inheritance chains. Using the as operator followed by a test for null is more performing.

Starting with C# 7.0 you can simplify the code by using pattern matching:

if (obj is T t) {
    // t is a variable of type T having a non-null value.

Btw.: this works for value types as well. Very handy for testing and unboxing. Note that you cannot test for nullable value types:

if (o is int? ni) ===> does NOT compile!

This is because either the value is null or it is an int. This works for int? o as well as for object o = new Nullable<int>(x);:

if (o is int i) ===> OK!

I like it, because it eliminates the need to access the Nullable<T>.Value property.

How to accept Date params in a GET request to Spring MVC Controller?

This is what I did to get formatted date from front end

  @RequestMapping(value = "/{dateString}", method = RequestMethod.GET)
  public HttpStatus getSomething(@PathVariable @DateTimeFormat(iso = DateTimeFormat.ISO.DATE) String dateString) {
   return OK;

You can use it to get what you want.

Click a button programmatically

Best implementation depends of what you are attempting to do exactly. Nadeem_MK gives you a valid one. Know you can also:

  1. raise the Button2_Click event using PerformClick() method:

    Private Sub Button1_Click(sender As Object, e As System.EventArgs) Handles Button1.Click
        'do stuff
    End Sub
  2. attach the same handler to many buttons:

    Private Sub Button1_Click(sender As Object, e As System.EventArgs) _
        Handles Button1.Click, Button2.Click
        'do stuff
    End Sub
  3. call the Button2_Click method using the same arguments than Button1_Click(...) method (IF you need to know which is the sender, for example) :

    Private Sub Button1_Click(sender As Object, e As System.EventArgs) Handles Button1.Click
        'do stuff
         Button2_Click(sender, e)
    End Sub

How to make a parent div auto size to the width of its children divs

The parent div (I assume the outermost div) is display: block and will fill up all available area of its container (in this case, the body) that it can. Use a different display type -- inline-block is probably what you are going for:

How to print SQL statement in codeigniter model

if you need a quick test on your query, this works great for me

echo $this->db->last_query(); die;

Convert Pandas Column to DateTime

raw_data['Mycol'] =  pd.to_datetime(raw_data['Mycol'], format='%d%b%Y:%H:%M:%S.%f')

works, however it results in a Python warning of A value is trying to be set on a copy of a slice from a DataFrame. Try using .loc[row_indexer,col_indexer] = value instead

I would guess this is due to some chaining indexing.

Can't update: no tracked branch

Assume you have a local branch "Branch-200" (or other name) and server repository contains "origin/Branch-1". If you have local "Branch-1" not linked with "origin/Branch-1", rename it to "Branch-200".

In Android Studio checkout to "origin/Branch-1" creating a new local branch "Branch-1", then merge with you local branch "Branch-200".

How do I use InputFilter to limit characters in an EditText in Android?

Use this its work 100% your need and very simple.

android:digits="@string/myAlphaNumeric" />

In strings.xml

<string name="myAlphaNumeric">abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789</string>

How to retrieve the hash for the current commit in Git?

Here is another way of doing it with :)

git log | grep -o '\w\{8,\}' | head -n 1

Online SQL Query Syntax Checker

SQLFiddle will let you test out your queries, while it doesn't explicitly correct syntax etc. per se it does let you play around with the script and will definitely let you know if things are working or not.

What's the bad magic number error?

This can also happen if you have the wrong python27.dll file (in case of Windows), to solve this just re-install (or extract) python with the exact corresponding dll version. I had a similar experience.

invalid use of non-static data member

The nested class doesn't know about the outer class, and protected doesn't help. You'll have to pass some actual reference to objects of the nested class type. You could store a foo*, but perhaps a reference to the integer is enough:

class Outer
    int n;

    class Inner
        int & a;
        Inner(int & b) : a(b) { }
        int & get() { return a; }

    // ...  for example:

    Inner inn;
    Outer() : inn(n) { }

Now you can instantiate inner classes like Inner i(n); and call i.get().

MySQL Workbench Dark Theme

MySQL Workbench 8.0 Update

Based on Gunther's answer, it seems like in code_editor.xml they're planning to enable a dark mode at some point down the road. What was once fore-color has now been split into fore-color-light and fore-color-dark. Likewise with back-color.

Here's how to get a dark editor (not whole application theme) based on the Monokai colours provided graciously by elMestre:

dark-gray:         #282828;
brown-gray:        #49483E;
gray:              #888888;
light-gray:        #CCCCCC;
ghost-white:       #F8F8F0;
light-ghost-white: #F8F8F2;
yellow:            #E6DB74;
blue:              #66D9EF;
pink:              #F92672;
purple:            #AE81FF;
brown:             #75715E;
orange:            #FD971F;
light-orange:      #FFD569;
green:             #A6E22E;
sea-green:         #529B2F; 

<style id="32" fore-color-light="#DDDDDD" back-color-light="#282828" fore-color-dark="#DDDDDD" back-color-dark="#282828" bold="No" />   <!-- STYLE_DEFAULT       !BACKGROUND!   -->
<style id="33" fore-color-light="#DDDDDD" back-color-light="#282828" fore-color-dark="#DDDDDD" back-color-dark="#282828" bold="No" />   <!-- STYLE_LINENUMBER                   -->
<style id= "0" fore-color-light="#DDDDDD" back-color-light="#282828" fore-color-dark="#DDDDDD" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_DEFAULT                  -->

<style id= "1" fore-color-light="#999999" back-color-light="#282828" fore-color-dark="#999999" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_COMMENT                  -->
<style id= "2" fore-color-light="#999999" back-color-light="#282828" fore-color-dark="#999999" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_COMMENTLINE              -->
<style id= "3" fore-color-light="#DDDDDD" back-color-light="#282828" fore-color-dark="#DDDDDD" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_VARIABLE                 -->
<style id= "4" fore-color-light="#66D9EF" back-color-light="#282828" fore-color-dark="#66D9EF" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_SYSTEMVARIABLE           -->
<style id= "5" fore-color-light="#66D9EF" back-color-light="#282828" fore-color-dark="#66D9EF" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_KNOWNSYSTEMVARIABLE      -->
<style id= "6" fore-color-light="#AE81FF" back-color-light="#282828" fore-color-dark="#AE81FF" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_NUMBER                   -->
<style id= "7" fore-color-light="#F92672" back-color-light="#282828" fore-color-dark="#F92672" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_MAJORKEYWORD             -->
<style id= "8" fore-color-light="#F92672" back-color-light="#282828" fore-color-dark="#F92672" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_KEYWORD                  -->
<style id= "9" fore-color-light="#9B859D" back-color-light="#282828" fore-color-dark="#9B859D" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_DATABASEOBJECT           -->
<style id="10" fore-color-light="#DDDDDD" back-color-light="#282828" fore-color-dark="#DDDDDD" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_PROCEDUREKEYWORD         -->
<style id="11" fore-color-light="#E6DB74" back-color-light="#282828" fore-color-dark="#E6DB74" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_STRING                   -->
<style id="12" fore-color-light="#E6DB74" back-color-light="#282828" fore-color-dark="#E6DB74" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_SQSTRING                 -->
<style id="13" fore-color-light="#E6DB74" back-color-light="#282828" fore-color-dark="#E6DB74" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_DQSTRING                 -->
<style id="14" fore-color-light="#F92672" back-color-light="#282828" fore-color-dark="#F92672" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_OPERATOR                 -->
<style id="15" fore-color-light="#9B859D" back-color-light="#282828" fore-color-dark="#9B859D" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_FUNCTION                 -->
<style id="16" fore-color-light="#DDDDDD" back-color-light="#282828" fore-color-dark="#DDDDDD" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_IDENTIFIER               -->
<style id="17" fore-color-light="#E6DB74" back-color-light="#282828" fore-color-dark="#E6DB74" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_QUOTEDIDENTIFIER         -->
<style id="18" fore-color-light="#529B2F" back-color-light="#282828" fore-color-dark="#529B2F" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_USER1                    -->
<style id="19" fore-color-light="#529B2F" back-color-light="#282828" fore-color-dark="#529B2F" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_USER2                    -->
<style id="20" fore-color-light="#529B2F" back-color-light="#282828" fore-color-dark="#529B2F" back-color-dark="#282828" bold="No" />   <!-- SCE_MYSQL_USER3                    -->
<style id="21" fore-color-light="#66D9EF" back-color-light="#49483E" fore-color-dark="#66D9EF" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_HIDDENCOMMAND            -->
<style id="22" fore-color-light="#909090" back-color-light="#49483E" fore-color-dark="#909090" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_PLACEHOLDER              -->
<!-- All styles again in their variant in a hidden command -->
<style id="65" fore-color-light="#999999" back-color-light="#49483E" fore-color-dark="#999999" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_COMMENT                  -->
<style id="66" fore-color-light="#999999" back-color-light="#49483E" fore-color-dark="#999999" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_COMMENTLINE              -->
<style id="67" fore-color-light="#DDDDDD" back-color-light="#49483E" fore-color-dark="#DDDDDD" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_VARIABLE                 -->
<style id="68" fore-color-light="#66D9EF" back-color-light="#49483E" fore-color-dark="#66D9EF" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_SYSTEMVARIABLE           -->
<style id="69" fore-color-light="#66D9EF" back-color-light="#49483E" fore-color-dark="#66D9EF" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_KNOWNSYSTEMVARIABLE      -->
<style id="70" fore-color-light="#AE81FF" back-color-light="#49483E" fore-color-dark="#AE81FF" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_NUMBER                   -->
<style id="71" fore-color-light="#F92672" back-color-light="#49483E" fore-color-dark="#F92672" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_MAJORKEYWORD             -->
<style id="72" fore-color-light="#F92672" back-color-light="#49483E" fore-color-dark="#F92672" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_KEYWORD                  -->
<style id="73" fore-color-light="#9B859D" back-color-light="#49483E" fore-color-dark="#9B859D" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_DATABASEOBJECT           -->
<style id="74" fore-color-light="#DDDDDD" back-color-light="#49483E" fore-color-dark="#DDDDDD" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_PROCEDUREKEYWORD         -->
<style id="75" fore-color-light="#E6DB74" back-color-light="#49483E" fore-color-dark="#E6DB74" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_STRING                   -->
<style id="76" fore-color-light="#E6DB74" back-color-light="#49483E" fore-color-dark="#E6DB74" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_SQSTRING                 -->
<style id="77" fore-color-light="#E6DB74" back-color-light="#49483E" fore-color-dark="#E6DB74" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_DQSTRING                 -->
<style id="78" fore-color-light="#F92672" back-color-light="#49483E" fore-color-dark="#F92672" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_OPERATOR                 -->
<style id="79" fore-color-light="#9B859D" back-color-light="#49483E" fore-color-dark="#9B859D" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_FUNCTION                 -->
<style id="80" fore-color-light="#DDDDDD" back-color-light="#49483E" fore-color-dark="#DDDDDD" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_IDENTIFIER               -->
<style id="81" fore-color-light="#E6DB74" back-color-light="#49483E" fore-color-dark="#E6DB74" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_QUOTEDIDENTIFIER         -->
<style id="82" fore-color-light="#529B2F" back-color-light="#49483E" fore-color-dark="#529B2F" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_USER1                    -->
<style id="83" fore-color-light="#529B2F" back-color-light="#49483E" fore-color-dark="#529B2F" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_USER2                    -->
<style id="84" fore-color-light="#529B2F" back-color-light="#49483E" fore-color-dark="#529B2F" back-color-dark="#49483E" bold="No" />   <!-- SCE_MYSQL_USER3                    -->
<style id="85" fore-color-light="#66D9EF" back-color-light="#888888" fore-color-dark="#66D9EF" back-color-dark="#888888" bold="No" />   <!-- SCE_MYSQL_HIDDENCOMMAND            -->
<style id="86" fore-color-light="#AAAAAA" back-color-light="#888888" fore-color-dark="#AAAAAA" back-color-dark="#888888" bold="No" />   <!-- SCE_MYSQL_PLACEHOLDER              -->  

Remember to paste all these styles inside of the <language name="SCLEX_MYSQL"> tag in data > code_editor.xml.

enter image description here

Where do I find the current C or C++ standard documents?

The text of a draft of the ANSI C standard (aka C.89) is available online. This was standardized by the ANSI committee prior to acceptance by the ISO C Standard (C.90), so the numbering of the sections differ (ANSI sections 2 through 4 correspond roughly to ISO sections 5 through 7), although the content is (supposed to be) largely identical.

Run git pull over all subdirectories

None of the top 5 answers worked for me, and the question talked about directories.

This worked:

for d in *; do pushd $d && git pull && popd; done

Create the perfect JPA entity

My 2 cents addition to the answers here are:

  1. With reference to Field or Property access (away from performance considerations) both are legitimately accessed by means of getters and setters, thus, my model logic can set/get them in the same manner. The difference comes to play when the persistence runtime provider (Hibernate, EclipseLink or else) needs to persist/set some record in Table A which has a foreign key referring to some column in Table B. In case of a Property access type, the persistence runtime system uses my coded setter method to assign the cell in Table B column a new value. In case of a Field access type, the persistence runtime system sets the cell in Table B column directly. This difference is not of importance in the context of a uni-directional relationship, yet it is a MUST to use my own coded setter method (Property access type) for a bi-directional relationship provided the setter method is well designed to account for consistency. Consistency is a critical issue for bi-directional relationships refer to this link for a simple example for a well-designed setter.

  2. With reference to Equals/hashCode: It is impossible to use the Eclipse auto-generated Equals/hashCode methods for entities participating in a bi-directional relationship, otherwise they will have a circular reference resulting in a stackoverflow Exception. Once you try a bidirectional relationship (say OneToOne) and auto-generate Equals() or hashCode() or even toString() you will get caught in this stackoverflow exception.

Mac OS X - EnvironmentError: mysql_config not found

Also this happens when I was installing mysqlclient,

$ pip install mysqlclient

As user3429036 said,

$ brew install mysql

Publish to IIS, setting Environment Variable

To get the details about the error I had to add ASPNETCORE_ENVIRONMENT environment variable for the corresponding Application Pool system.applicationHost/applicationPools.

Note: the web application in my case was ASP.NET Core 2 web application hosted on IIS 10. It can be done via Configuration Editor in IIS Manager (see Editing Collections with Configuration Editor to figure out where to find this editor in IIS Manager).

Can a background image be larger than the div itself?

Not really - the background image is bounded by the element it's applied to, and the overflow properties only apply to the content (i.e. markup) within an element.

You can add another div into your footer div and apply the background image to that, though, and have that overflow instead.

Excel VBA - select a dynamic cell range

I like to used this method the most, it will auto select the first column to the last column being used. However, if the last cell in the first row or the last cell in the first column are empty, this code will not calculate properly. Check the link for other methods to dynamically select cell range.

Sub DynamicRange()
'Best used when first column has value on last row and first row has a value in the last column

Dim sht As Worksheet
Dim LastRow As Long
Dim LastColumn As Long
Dim StartCell As Range

Set sht = Worksheets("Sheet1")
Set StartCell = Range("A1")

'Find Last Row and Column
  LastRow = sht.Cells(sht.Rows.Count, StartCell.Column).End(xlUp).Row
  LastColumn = sht.Cells(StartCell.Row, sht.Columns.Count).End(xlToLeft).Column

'Select Range
  sht.Range(StartCell, sht.Cells(LastRow, LastColumn)).Select

End Sub

SELECT INTO Variable in MySQL DECLARE causes syntax error?

It is worth noting that despite the fact that you can SELECT INTO global variables like:


You can NOT use FETCH INTO global variables like:


Looks like it's not a bug. I hope it will be helpful to someone...

UINavigationBar Hide back Button Text

This is from my xamarin.forms code, the class derives from NavigationRenderer

NavigationBar.Items.FirstOrDefault().BackBarButtonItem = new UIBarButtonItem( "", UIBarButtonItemStyle.Plain, null);

CSS / HTML Navigation and Logo on same line

Firstly, let's use some semantic HTML.

<nav class="navigation-bar">
    <img class="logo" src="logo.png">
        <li><a href="#">Home</a></li>
        <li><a href="#">Projects</a></li>
        <li><a href="#">About</a></li>
        <li><a href="#">Services</a></li>
        <li><a href="#">Get in Touch</a></li>

In fact, you can even get away with the more minimalist:

<nav class="navigation-bar">
    <img class="logo" src="logo.png">
    <a href="#">Home</a>
    <a href="#">Projects</a>
    <a href="#">About</a>
    <a href="#">Services</a>
    <a href="#">Get in Touch</a>

Then add some CSS:

.navigation-bar {
    width: 100%;  /* i'm assuming full width */
    height: 80px; /* change it to desired width */
    background-color: red; /* change to desired color */
.logo {
    display: inline-block;
    vertical-align: top;
    width: 50px;
    height: 50px;
    margin-right: 20px;
    margin-top: 15px;    /* if you want it vertically middle of the navbar. */
.navigation-bar > a {
    display: inline-block;
    vertical-align: top;
    margin-right: 20px;
    height: 80px;        /* if you want it to take the full height of the bar */
    line-height: 80px;    /* if you want it vertically middle of the navbar */

Obviously, the actual margins, heights and line-heights etc. depend on your design.

Other options are to use tables or floats for layout, but these are generally frowned upon.

Last but not least, I hope you get cured of div-itis.

Adding Http Headers to HttpClient

Create a HttpRequestMessage, set the Method to GET, set your headers and then use SendAsync instead of GetAsync.

var client = new HttpClient();
var request = new HttpRequestMessage() {
    RequestUri = new Uri(""),
    Method = HttpMethod.Get,
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("text/plain"));
var task = client.SendAsync(request)
    .ContinueWith((taskwithmsg) =>
        var response = taskwithmsg.Result;

        var jsonTask = response.Content.ReadAsAsync<JsonObject>();
        var jsonObject = jsonTask.Result;

How to create and handle composite primary key in JPA

The MyKey class (@Embeddable) should not have any relationships like @ManyToOne

Guzzle 6: no more json() method for responses

If you guys still interested, here is my workaround based on Guzzle middleware feature:

  1. Create JsonAwaraResponse that will decode JSON response by Content-Type HTTP header, if not - it will act as standard Guzzle Response:

    namespace GuzzleHttp\Psr7;
    class JsonAwareResponse extends Response
         * Cache for performance
         * @var array
        private $json;
        public function getBody()
            if ($this->json) {
                return $this->json;
            // get parent Body stream
            $body = parent::getBody();
            // if JSON HTTP header detected - then decode
            if (false !== strpos($this->getHeaderLine('Content-Type'), 'application/json')) {
                return $this->json = \json_decode($body, true);
            return $body;
  2. Create Middleware which going to replace Guzzle PSR-7 responses with above Response implementation:

    $client = new \GuzzleHttp\Client();
    /** @var HandlerStack $handler */
    $handler = $client->getConfig('handler');
    $handler->push(\GuzzleHttp\Middleware::mapResponse(function (\Psr\Http\Message\ResponseInterface $response) {
        return new \GuzzleHttp\Psr7\JsonAwareResponse(
    }), 'json_decode_middleware');

After this to retrieve JSON as PHP native array use Guzzle as always:

$jsonArray = $client->get('')->getBody();

Tested with guzzlehttp/guzzle 6.3.3

Can the Unix list command 'ls' output numerical chmod permissions?

Use this to display the Unix numerical permission values (octal values) and file name.

stat -c '%a %n' *

Use this to display the Unix numerical permission values (octal values) and the folder's sgid and sticky bit, user name of the owner, group name, total size in bytes and file name.

stat -c '%a %A %U %G %s %n' *

enter image description here

Add %y if you need time of last modification in human-readable format. For more options see stat.

Better version using an Alias

Using an alias is a more efficient way to accomplish what you need and it also includes color. The following displays your results organized by group directories first, display in color, print sizes in human readable format (e.g., 1K 234M 2G) edit your ~/.bashrc and add an alias for your account or globally by editing /etc/profile.d/

Typing cls displays your new LS command results.

alias cls="ls -lha --color=always -F --group-directories-first |awk '{k=0;s=0;for(i=0;i<=8;i++){;k+=((substr(\$1,i+2,1)~/[rwxst]/)*2^(8-i));};j=4;for(i=4;i<=10;i+=3){;s+=((substr(\$1,i,1)~/[stST]/)*j);j/=2;};if(k){;printf(\"%0o%0o \",s,k);};print;}'"

Alias is the most efficient solution

Folder Tree

While you are editing your bashrc or include the following alias to see a graphical representation where typing lstree will display your current folder tree structure

alias lstree="ls -R | grep ":$" | sed -e 's/:$//' -e 's/[^-][^\/]*\//--/g' -e 's/^/   /' -e 's/-/|/'"

It would display:


How do I change an HTML selected option using JavaScript?


document.getElementById('personlist').getElementsByTagName('option')[11].selected = 'selected'



javascript password generator

This will produce a realistic password if having characters [\]^_ is fine. Requires lodash and es7

String.fromCodePoint(...range(8).map(() => Math.floor(Math.random() * 57) + 0x41))

and here's without lodash

String.fromCodePoint(...Array.from({length: 8}, () => Math.floor(Math.random() * 57) + 65))

How to check if current thread is not main thread

Xamarin.Android port: (C#)

public bool IsMainThread => Build.VERSION.SdkInt >= BuildVersionCodes.M
    ? Looper.MainLooper.IsCurrentThread
    : Looper.MyLooper() == Looper.MainLooper;


if (IsMainThread) {
    // you are on UI/Main thread

How to set an iframe src attribute from a variable in AngularJS

You need also $sce.trustAsResourceUrl or it won't open the website inside the iframe:

angular.module('myApp', [])_x000D_
    .controller('dummy', ['$scope', '$sce', function ($scope, $sce) {_x000D_
    $scope.url = $sce.trustAsResourceUrl('');_x000D_
    $scope.changeIt = function () {_x000D_
        $scope.url = $sce.trustAsResourceUrl('');_x000D_
<script src=""></script>_x000D_
<div ng-app="myApp" ng-controller="dummy">_x000D_
    <iframe ng-src="{{url}}" width="300" height="200"></iframe>_x000D_
    <button ng-click="changeIt()">Change it</button>_x000D_

Change image size with JavaScript

//  This one has print statement so you can see the result at every stage if     you would like.  They are not needed

function crop(image, width, height)
    image.width = width;
    image.height = height;
    //print ("in function", image, image.getWidth(), image.getHeight());
    return image;

var image = new SimpleImage("name of your image here");
//print ("original", image, image.getWidth(), image.getHeight());
print ("final", image, image.getWidth(), image.getHeight());

Android Studio - Emulator - eglSurfaceAttrib not implemented

Fix: Unlock your device before running it.

Hi Guys: Think I may have a fix for this:

Sounds ridiculous but try unlocking your Virtual Device; i.e. use your mouse to swipe and open. Your app should then work!!

Getting Gradle dependencies in IntelliJ IDEA using Gradle build

Andrey's above post is still valid for the latest version of Intellij as of 3rd Quarter of 2017. So use it. 'Cause, build project, and external command line gradle build, does NOT add it to the external dependencies in Intellij...crazy as that sounds it is true. Only difference now is that the UI looks different to the above, but still the same icon for updating is used. I am only putting an answer here, cause I cannot paste a snapshot of the new UI...I dont want any up votes per se. Andrey still gave the correct answer above: enter image description here

What are the JavaScript KeyCodes?

Here are some useful links:

The 2nd column is the keyCode and the html column shows how it will displayed. You can test it here.

iPhone App Minus App Store?

After copying the the app to the iPhone in the way described by @Jason Weathered, make sure to "chmod +x" of the app, otherwise it won't run.

What parameters should I use in a Google Maps URL to go to a lat-lon?

yeah I had the same question for a long time and I found the perfect one. here are some parameters from it. = value


is used to specify the search query in Google maps search.
eg : or,-114.01679


is used to specify the location alternative to q=. Also has the added effect of allowing you to increase the AddressDetails Accuracy value by being more precise. Mostly only useful if query is a business or suchlike.


Zoom level. Can be set 19 normally, but in certain cases can go up to 23.


Latitude and longitude of the map centre point. Must be in that order. Requires decimal format. Interestingly, you can use this without q, in which case it doesn’t show a marker.


Similar to ll, only this sets the lat/long of the centre point for a business search. Requires the same input criteria as ll.


Sets the kind of map shown. Can be set to:

m – normal  map,
k – satellite,
h – hybrid,
p – terrain


Sets the starting point for directions searches. You can also add text into this in brackets to bold it in the directions sidebar.


Sets the end point for directions searches, and again will bold any text added in brackets.You can also add "+to:" which will set via points. These can be added multiple times.


Allows you to insert via points in directions. Must be in CSV format. For example, via=1,5 addresses 1 and 5 will be via points without entries in the sidebar. The start point (which is set as 0), and 2, 3 and 4 will all show full addresses.


Changes the units used to measure distance (will default to the standard unit in country of origin). Change to ptk for metric or ptm for imperial.


Does stuff with My Maps. Set to 0 show defined My Maps, b to turn the My Maps sidebar on, 1 to show the My Maps tab on its own, or 2 to go to the new My Map creator form.


can set miscellaneous values below:

h - Avoid highway
t - Avoid tolls


Nodejs cannot find installed module on Windows

For me worked on Windows 10 npm config set prefix %AppData%\npm\node_modules

How to use the start command in a batch file?

I think this other Stack Overflow answer would solve your problem: How do I run a bat file in the background from another bat file?

Basically, you use the /B and /C options:

START /B CMD /C CALL "foo.bat" [args [...]] >NUL 2>&1

Adding files to java classpath at runtime

Try this one on for size.

private static void addSoftwareLibrary(File file) throws Exception {
    Method method = URLClassLoader.class.getDeclaredMethod("addURL", new Class[]{URL.class});
    method.invoke(ClassLoader.getSystemClassLoader(), new Object[]{file.toURI().toURL()});

This edits the system class loader to include the given library jar. It is pretty ugly, but it works.

External VS2013 build error "error MSB4019: The imported project <path> was not found"

You should copy folder WebApplications from C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v12.0\ to C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v11.0\

jQuery append text inside of an existing paragraph tag

Try this


Why should I use core.autocrlf=true in Git?

The only specific reasons to set autocrlf to true are:

  • avoid git status showing all your files as modified because of the automatic EOL conversion done when cloning a Unix-based EOL Git repo to a Windows one (see issue 83 for instance)
  • and your coding tools somehow depends on a native EOL style being present in your file:

Unless you can see specific treatment which must deal with native EOL, you are better off leaving autocrlf to false (git config --global core.autocrlf false).

Note that this config would be a local one (because config isn't pushed from repo to repo)

If you want the same config for all users cloning that repo, check out "What's the best CRLF handling strategy with git?", using the text attribute in the .gitattributes file.


*.vcproj    text eol=crlf
*.sh        text eol=lf

Note: starting git 2.8 (March 2016), merge markers will no longer introduce mixed line ending (LF) in a CRLF file.
See "Make Git use CRLF on its “<<<<<<< HEAD” merge lines"

Assign result of dynamic sql to variable

Sample to execute an SQL string within the stored procedure:

(I'm using this to compare the number of entries on each table as first check for a regression test, within a cursor loop)

select @SqlQuery1 = N'select @CountResult1 = (select isnull(count(*),0) from ' + @DatabaseFirst+'.dbo.'+@ObjectName + ')'

execute sp_executesql    @SqlQuery1 , N'@CountResult1 int OUTPUT',     @CountResult1 = @CountResult1 output;

How to make Twitter Bootstrap menu dropdown on hover rather than click

I created a pure on hover dropdown menu based on the latest (v2.0.2) Bootstrap framework that has support for multiple submenus and thought I'd post it for future users:

body {_x000D_
  padding-top: 60px;_x000D_
  padding-bottom: 40px;_x000D_
.sidebar-nav {_x000D_
  padding: 9px 0;_x000D_
.dropdown-menu .sub-menu {_x000D_
  left: 100%;_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  visibility: hidden;_x000D_
  margin-top: -1px;_x000D_
.dropdown-menu li:hover .sub-menu {_x000D_
  visibility: visible;_x000D_
.dropdown:hover .dropdown-menu {_x000D_
  display: block;_x000D_
.nav-tabs .dropdown-menu,_x000D_
.nav-pills .dropdown-menu,_x000D_
.navbar .dropdown-menu {_x000D_
  margin-top: 0;_x000D_
.navbar .sub-menu:before {_x000D_
  border-bottom: 7px solid transparent;_x000D_
  border-left: none;_x000D_
  border-right: 7px solid rgba(0, 0, 0, 0.2);_x000D_
  border-top: 7px solid transparent;_x000D_
  left: -7px;_x000D_
  top: 10px;_x000D_
.navbar .sub-menu:after {_x000D_
  border-top: 6px solid transparent;_x000D_
  border-left: none;_x000D_
  border-right: 6px solid #fff;_x000D_
  border-bottom: 6px solid transparent;_x000D_
  left: 10px;_x000D_
  top: 11px;_x000D_
  left: -6px;_x000D_
<link href="" rel="stylesheet" />_x000D_
<div class="navbar navbar-fixed-top">_x000D_
  <div class="navbar-inner">_x000D_
    <div class="container-fluid">_x000D_
      <a data-target=".nav-collapse" data-toggle="collapse" class="btn btn-navbar">_x000D_
        <span class="icon-bar"></span>_x000D_
        <span class="icon-bar"></span>_x000D_
        <span class="icon-bar"></span>_x000D_
      <a href="#" class="brand">Project name</a>_x000D_
      <div class="nav-collapse">_x000D_
        <ul class="nav">_x000D_
          <li class="active"><a href="#">Home</a></li>_x000D_
          <li><a href="#">Link</a></li>_x000D_
          <li><a href="#">Link</a></li>_x000D_
          <li><a href="#">Link</a></li>_x000D_
          <li class="dropdown">_x000D_
            <a data-toggle="dropdown" class="dropdown-toggle" href="#">Dropdown <b class="caret"></b></a>_x000D_
            <ul class="dropdown-menu">_x000D_
                <a href="#">2-level Dropdown <i class="icon-arrow-right"></i></a>_x000D_
                <ul class="dropdown-menu sub-menu">_x000D_
                  <li><a href="#">Action</a></li>_x000D_
                  <li><a href="#">Another action</a></li>_x000D_
                  <li><a href="#">Something else here</a></li>_x000D_
                  <li class="divider"></li>_x000D_
                  <li class="nav-header">Nav header</li>_x000D_
                  <li><a href="#">Separated link</a></li>_x000D_
                  <li><a href="#">One more separated link</a></li>_x000D_
              <li><a href="#">Another action</a></li>_x000D_
              <li><a href="#">Something else here</a></li>_x000D_
              <li class="divider"></li>_x000D_
              <li class="nav-header">Nav header</li>_x000D_
              <li><a href="#">Separated link</a></li>_x000D_
              <li><a href="#">One more separated link</a></li>_x000D_
        <form action="" class="navbar-search pull-left">_x000D_
          <input type="text" placeholder="Search" class="search-query span2">_x000D_
        <ul class="nav pull-right">_x000D_
          <li><a href="#">Link</a></li>_x000D_
          <li class="divider-vertical"></li>_x000D_
          <li class="dropdown">_x000D_
            <a class="#" href="#">Menu</a>_x000D_
      <!-- /.nav-collapse -->_x000D_
<ul class="nav nav-pills">_x000D_
  <li class="active"><a href="#">Regular link</a></li>_x000D_
  <li class="dropdown">_x000D_
    <a href="#" data-toggle="dropdown" class="dropdown-toggle">Dropdown <b class="caret"></b></a>_x000D_
    <ul class="dropdown-menu" id="menu1">_x000D_
        <a href="#">2-level Menu <i class="icon-arrow-right"></i></a>_x000D_
        <ul class="dropdown-menu sub-menu">_x000D_
          <li><a href="#">Action</a></li>_x000D_
          <li><a href="#">Another action</a></li>_x000D_
          <li><a href="#">Something else here</a></li>_x000D_
          <li class="divider"></li>_x000D_
          <li class="nav-header">Nav header</li>_x000D_
          <li><a href="#">Separated link</a></li>_x000D_
          <li><a href="#">One more separated link</a></li>_x000D_
      <li><a href="#">Another action</a></li>_x000D_
      <li><a href="#">Something else here</a></li>_x000D_
      <li class="divider"></li>_x000D_
      <li><a href="#">Separated link</a></li>_x000D_
  <li class="dropdown">_x000D_
    <a href="#">Menu</a>_x000D_
  <li class="dropdown">_x000D_
    <a href="#">Menu</a>_x000D_


android: how to use getApplication and getApplicationContext from non activity / service class

The getApplication() method is located in the Activity class, so whenever you want getApplication() in a non activity class you have to pass an Activity instance to the constructor of that non activity class.

assume that test is my non activity class:

Test test = new Test(this);

In that class i have created one constructor:

 public Class Test
    public Activity activity;
    public Test (Activity act)
         this.activity = act;
         // Now here you can get getApplication()

find difference between two text files with one item per line

If you want to use loops You can try like this: (diff and cmp are much more efficient. )

while read line
    flag = 0
    while read line2
       if ( "$line" = "$line2" )
            flag = 1
     done < file1 
     if ( flag -eq 0 )
         echo $line > file3
done < file2

Note: The program is only to provide a basic insight into what can be done if u dont want to use system calls such as diff n comm..

How to call a javaScript Function in jsp on page load without using <body onload="disableView()">

Either use window.onload this way

    window.onload = function() {
        // ...

or alternatively

    window.onload = functionName;

(yes, without the parentheses)

Or just put the script at the very bottom of page, right before </body>. At that point, all HTML DOM elements are ready to be accessed by document functions.



Laravel: Get Object From Collection By Attribute

Elegant solution for finding a value ( can be adapted:

$desired_object_key = $food->array_search(24, $food->lists('id'));
if ($desired_object_key !== false) {
   $desired_object = $food[$desired_object_key];

Does Python have a toString() equivalent, and can I convert a db.Model element to String?

In Python we can use the __str__() method.

We can override it in our class like this:

class User: 

    firstName = ''
    lastName = ''

    def __str__(self):
        return self.firstName + " " + self.lastName

and when running


it will call the function __str__(self) and print the firstName and lastName

How do I execute external program within C code in linux with arguments?

You can use fork() and system() so that your program doesn't have to wait until system() returns.

#include <stdio.h>
#include <stdlib.h>

int main(int argc,char* argv[]){

    int status;

    // By calling fork(), a child process will be created as a exact duplicate of the calling process.
    // Search for fork() (maybe "man fork" on Linux) for more information.
    if(fork() == 0){ 
        // Child process will return 0 from fork()
        printf("I'm the child process.\n");
        status = system("my_app");
        // Parent process will return a non-zero value from fork()
        printf("I'm the parent.\n");

    printf("This is my main program and it will continue running and doing anything i want to...\n");

    return 0;

How to split a comma-separated value to columns

This worked for me

CREATE FUNCTION [dbo].[SplitString](
    @delimited NVARCHAR(MAX),
    @delimiter NVARCHAR(100)
    DECLARE @xml XML
    SET @xml = N'<t>' + REPLACE(@delimited,@delimiter,'</t><t>') + '</t>'
    INSERT INTO @t(val)
    SELECT  r.value('.','varchar(MAX)') as item
    FROM  @xml.nodes('/t') as records(r)

Read from database and fill DataTable

Private Function LoaderData(ByVal strSql As String) As DataTable
    Dim cnn As SqlConnection
    Dim dad As SqlDataAdapter

    Dim dtb As New DataTable
    cnn = New SqlConnection(My.Settings.mySqlConnectionString)
        dad = New SqlDataAdapter(strSql, cnn)
    Catch ex As Exception
    End Try
    Return dtb
End Function

Favicon dimensions?

Wikipedia has this to say:

Additionally, such icon files can be either 16×16 or 32×32 pixels in size, and either 8-bit or 24-bit in color depth (note that GIF files have a limited, 256 color palette entries).

I think the best way is to use a 32x32 gif and test it with different browsers.

What svn command would list all the files modified on a branch?

svn log -q -v shows paths and hides comments. All the paths are indented so you can search for lines starting with whitespace. Then pipe to cut and sort to tidy up:

svn log --stop-on-copy -q -v | grep '^[[:space:]]'| cut -c6- | sort -u

This gets all the paths mentioned on the branch since its branch point. Note it will list deleted and added, as well as modified files. I just used this to get the stuff I should worry about reviewing on a slightly messy branch from a new dev.

double free or corruption (!prev) error in c program

double *ptr = malloc(sizeof(double *) * TIME);
/* ... */
for(tcount = 0; tcount <= TIME; tcount++)
  • You're overstepping the array. Either change <= to < or alloc SIZE + 1 elements
  • Your malloc is wrong, you'll want sizeof(double) instead of sizeof(double *)
  • As ouah comments, although not directly linked to your corruption problem, you're using *(ptr+tcount) without initializing it

  • Just as a style note, you might want to use ptr[tcount] instead of *(ptr + tcount)
  • You don't really need to malloc + free since you already know SIZE

Print array elements on separate lines in Bash?

Just quote the argument to echo:

( IFS=$'\n'; echo "${my_array[*]}" )

the sub shell helps restoring the IFS after use

How to filter rows in pandas by regex

Using str slice

   a    b
1  2  foo
2  3  fat

sorting dictionary python 3

The accepted answer definitely works, but somehow miss an important point.

The OP is asking for a dictionary sorted by it's keys this is just not really possible and not what OrderedDict is doing.

OrderedDict is maintaining the content of the dictionary in insertion order. First item inserted, second item inserted, etc.

>>> d = OrderedDict()
>>> d['foo'] = 1
>>> d['bar'] = 2
>>> d
OrderedDict([('foo', 1), ('bar', 2)])

>>> d = OrderedDict()
>>> d['bar'] = 2
>>> d['foo'] = 1
>>> d
OrderedDict([('bar', 2), ('foo', 1)])

Hencefore I won't really be able to sort the dictionary inplace, but merely to create a new dictionary where insertion order match key order. This is explicit in the accepted answer where the new dictionary is b.

This may be important if you are keeping access to dictionaries through containers. This is also important if you itend to change the dictionary later by adding or removing items: they won't be inserted in key order but at the end of dictionary.

>>> d = OrderedDict({'foo': 5, 'bar': 8})
>>> d
OrderedDict([('foo', 5), ('bar', 8)])
>>> d['alpha'] = 2
>>> d
OrderedDict([('foo', 5), ('bar', 8), ('alpha', 2)])

Now, what does mean having a dictionary sorted by it's keys ? That makes no difference when accessing elements by keys, this only matter when you are iterating over items. Making that a property of the dictionary itself seems like overkill. In many cases it's enough to sort keys() when iterating.

That means that it's equivalent to do:

>>> d = {'foo': 5, 'bar': 8}
>>> for k,v in d.iteritems(): print k, v

on an hypothetical sorted by key dictionary or:

>>> d = {'foo': 5, 'bar': 8}
>>> for k, v in iter((k, d[k]) for k in sorted(d.keys())): print k, v

Of course it is not hard to wrap that behavior in an object by overloading iterators and maintaining a sorted keys list. But it is likely overkill.

"ORA-01438: value larger than specified precision allowed for this column" when inserting 3

You can't update with a number greater than 1 for datatype number(2,2) is because, the first parameter is the total number of digits in the number and the second one (.i.e 2 here) is the number of digits in decimal part. I guess you can insert or update data < 1. i.e. 0.12, 0.95 etc.

Please check NUMBER DATATYPE in NUMBER Datatype.

Restrict SQL Server Login access to only one database

  1. Connect to your SQL server instance using management studio
  2. Goto Security -> Logins -> (RIGHT CLICK) New Login
  3. fill in user details
  4. Under User Mapping, select the databases you want the user to be able to access and configure


You'll also want to goto Security -> Server Roles, and for public check the permissions for TSQL Default TCP/TSQL Default VIA/TSQL Local Machine/TSQL Named Pipesand remove the connect permission

Count characters in textarea

We weren't happy with any of the purposed solutions.

So we've created a complete char counter solution for JQuery, built on top of jquery-jeditable. It's a textarea plugin extension that can count to both ways, displays a custom message, limits char count and also supports jquery-datatables.

You can test it right away on JSFiddle.

GitHub link:

Quick start

Add these lines to your HTML:

<script async src="[email protected]/dist/jquery.jeditable.charcounter.realworld.min.js"></script>
<script async src="[email protected]/dist/jquery.charcounter.realworld.min.js"></script>

And then:


How to correctly save instance state of Fragments in back stack?

I just want to give the solution that I came up with that handles all cases presented in this post that I derived from Vasek and devconsole. This solution also handles the special case when the phone is rotated more than once while fragments aren't visible.

Here is were I store the bundle for later use since onCreate and onSaveInstanceState are the only calls that are made when the fragment isn't visible

MyObject myObject;
private Bundle savedState = null;
private boolean createdStateInDestroyView;
private static final String SAVED_BUNDLE_TAG = "saved_bundle";

public void onCreate(Bundle savedInstanceState) {
    if (savedInstanceState != null) {
        savedState = savedInstanceState.getBundle(SAVED_BUNDLE_TAG);

Since destroyView isn't called in the special rotation situation we can be certain that if it creates the state we should use it.

public void onDestroyView() {
    savedState = saveState();
    createdStateInDestroyView = true;
    myObject = null;

This part would be the same.

private Bundle saveState() { 
    Bundle state = new Bundle();
    state.putSerializable(SAVED_BUNDLE_TAG, myObject);
    return state;

Now here is the tricky part. In my onActivityCreated method I instantiate the "myObject" variable but the rotation happens onActivity and onCreateView don't get called. Therefor, myObject will be null in this situation when the orientation rotates more than once. I get around this by reusing the same bundle that was saved in onCreate as the out going bundle.

public void onSaveInstanceState(Bundle outState) {

    if (myObject == null) {
        outState.putBundle(SAVED_BUNDLE_TAG, savedState);
    } else {
        outState.putBundle(SAVED_BUNDLE_TAG, createdStateInDestroyView ? savedState : saveState());
    createdStateInDestroyView = false;

Now wherever you want to restore the state just use the savedState bundle

public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    if(savedState != null) {
        myObject = (MyObject) savedState.getSerializable(SAVED_BUNDLE_TAG);

Python: Find a substring in a string and returning the index of the substring

Here is a simple approach:

my_string = 'abcdefg'



I the substring is not there, you will get -1. For example:

my_string = 'abcdefg'



Sometimes, you might want to throw exception if substring is not there:

my_string = 'abcdefg'
print(text.index('xyz')) # It returns an index only if it's present


Traceback (most recent call last):

File "", line 6, in print(text.index('xyz'))

ValueError: substring not found

failed to resolve and

Along with other provided solutions, make sure to have the following within project/build.gradle

allprojects {
    repositories {
        maven {
            url ""

Having Django serve downloadable files

For a very simple but not efficient or scalable solution, you can just use the built in django serve view. This is excellent for quick prototypes or one-off work, but as has been mentioned throughout this question, you should use something like apache or nginx in production.

from django.views.static import serve
filepath = '/some/path/to/local/file.txt'
return serve(request, os.path.basename(filepath), os.path.dirname(filepath))

Java: Convert String to TimeStamp

DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");

Date date = formatter.parse(dateString);

Timestamp timestamp = new Timestamp(date.getTime());


Find MongoDB records where array field is not empty

You can use any of the following to achieve this.
Both also take care of not returning a result for objects that don't have the requested key in them:{pictures: {$exists: true, $gt: {$size: 0}}}){comments: {$exists: true, $not: {$size: 0}}})

How do I override nested NPM dependency versions?

You can use npm shrinkwrap functionality, in order to override any dependency or sub-dependency.

I've just done this in a grunt project of ours. We needed a newer version of connect, since 2.7.3. was causing trouble for us. So I created a file named npm-shrinkwrap.json:

  "dependencies": {
    "grunt-contrib-connect": {
      "version": "0.3.0",
      "from": "[email protected]",
      "dependencies": {
        "connect": {
          "version": "2.8.1",
          "from": "connect@~2.7.3"

npm should automatically pick it up while doing the install for the project.


Run script on mac prompt "Permission denied"

In my case, I had made a stupid typo in the shebang.

So in case someone else on with fat fingers stumbles across this question:

Whoops: #!/usr/local/bin ruby

I meant to write: #!/usr/bin/env ruby

The vague error ZSH gives sent me down the wrong path:

ZSH: zsh: permission denied: ./foo.rb

Bash: bash: ./foo.rb: /usr/local/bin: bad interpreter: Permission denied

Editing legend (text) labels in ggplot

The legend titles can be labeled by specific aesthetic.

This can be achieved using the guides() or labs() functions from ggplot2 (more here and here). It allows you to add guide/legend properties using the aesthetic mapping.

Here's an example using the mtcars data set and labs():

ggplot(mtcars, aes(x=mpg, y=disp, size=hp, col=as.factor(cyl), shape=as.factor(gear))) +
  geom_point() +
  labs(x="miles per gallon", y="displacement", size="horsepower", 
       col="# of cylinders", shape="# of gears")

enter image description here

Answering the OP's question using guides():

# transforming the data from wide to long
dfm <- melt(df, id="TY")

# creating a scatterplot
ggplot(data = dfm, aes(x=TY, y=value, color=variable)) + 
  geom_point(size=5) +
  labs(title="Temperatures\n", x="TY [°C]", y="Txxx") +
  scale_color_manual(labels = c("T999", "T888"), values = c("blue", "red")) +
  theme_bw() +
  guides(color=guide_legend("my title"))  # add guide properties by aesthetic

enter image description here

How to add New Column with Value to the Existing DataTable?

Without For loop:

Dim newColumn As New Data.DataColumn("Foo", GetType(System.String))     
newColumn.DefaultValue = "Your DropDownList value" 


System.Data.DataColumn newColumn = new System.Data.DataColumn("Foo", typeof(System.String));
newColumn.DefaultValue = "Your DropDownList value";

nginx error "conflicting server name" ignored

You have another server_name somewhere in the config.

How can I add 1 day to current date?

int days = 1;
var newDate = new Date( + days*24*60*60*1000);


var days = 2;_x000D_
var newDate = new Date(*24*60*60*1000);_x000D_
document.write('Today: <em>');_x000D_
document.write(new Date());_x000D_
document.write('</em><br/> New: <strong>');_x000D_

Get the last item in an array

ES6 object destructuring is another way to go.

const {length, [length-1]: last}=[1,2,3,4,5]_x000D_

You extract length property from Array using object destructuring. You create another dynamic key using already extracted key by [length-1] and assign it to last, all in one line.

Handling of non breaking space: <p>&nbsp;</p> vs. <p> </p>

If I understand your issue this should work

&emsp—the em space; this should be a very wide space, typically as much as four real spaces. &ensp—the en space; this should be a somewhat wide space, roughly two regular spaces. &thinsp—this will be a narrow space, even more narrow than a regular space.


Android - Back button in the title bar

The other answers don't mention that you can also set this in the XML of your Toolbar widget:


For example:

    app:title="@string/title_activity_acoustic_progress" />

Using .NET, how can you find the mime type of a file based on the file signature not the extension

I found this one useful. For VB.NET developers:

    Public Shared Function GetFromFileName(ByVal fileName As String) As String
        Return GetFromExtension(Path.GetExtension(fileName).Remove(0, 1))
    End Function

    Public Shared Function GetFromExtension(ByVal extension As String) As String
        If extension.StartsWith("."c) Then
            extension = extension.Remove(0, 1)
        End If

        If MIMETypesDictionary.ContainsKey(extension) Then
            Return MIMETypesDictionary(extension)
        End If

        Return "unknown/unknown"
    End Function

    Private Shared ReadOnly MIMETypesDictionary As New Dictionary(Of String, String)() From { _
         {"ai", "application/postscript"}, _
         {"aif", "audio/x-aiff"}, _
         {"aifc", "audio/x-aiff"}, _
         {"aiff", "audio/x-aiff"}, _
         {"asc", "text/plain"}, _
         {"atom", "application/atom+xml"}, _
         {"au", "audio/basic"}, _
         {"avi", "video/x-msvideo"}, _
         {"bcpio", "application/x-bcpio"}, _
         {"bin", "application/octet-stream"}, _
         {"bmp", "image/bmp"}, _
         {"cdf", "application/x-netcdf"}, _
         {"cgm", "image/cgm"}, _
         {"class", "application/octet-stream"}, _
         {"cpio", "application/x-cpio"}, _
         {"cpt", "application/mac-compactpro"}, _
         {"csh", "application/x-csh"}, _
         {"css", "text/css"}, _
         {"dcr", "application/x-director"}, _
         {"dif", "video/x-dv"}, _
         {"dir", "application/x-director"}, _
         {"djv", "image/vnd.djvu"}, _
         {"djvu", "image/vnd.djvu"}, _
         {"dll", "application/octet-stream"}, _
         {"dmg", "application/octet-stream"}, _
         {"dms", "application/octet-stream"}, _
         {"doc", "application/msword"}, _
         {"dtd", "application/xml-dtd"}, _
         {"dv", "video/x-dv"}, _
         {"dvi", "application/x-dvi"}, _
         {"dxr", "application/x-director"}, _
         {"eps", "application/postscript"}, _
         {"etx", "text/x-setext"}, _
         {"exe", "application/octet-stream"}, _
         {"ez", "application/andrew-inset"}, _
         {"gif", "image/gif"}, _
         {"gram", "application/srgs"}, _
         {"grxml", "application/srgs+xml"}, _
         {"gtar", "application/x-gtar"}, _
         {"hdf", "application/x-hdf"}, _
         {"hqx", "application/mac-binhex40"}, _
         {"htm", "text/html"}, _
         {"html", "text/html"}, _
         {"ice", "x-conference/x-cooltalk"}, _
         {"ico", "image/x-icon"}, _
         {"ics", "text/calendar"}, _
         {"ief", "image/ief"}, _
         {"ifb", "text/calendar"}, _
         {"iges", "model/iges"}, _
         {"igs", "model/iges"}, _
         {"jnlp", "application/x-java-jnlp-file"}, _
         {"jp2", "image/jp2"}, _
         {"jpe", "image/jpeg"}, _
         {"jpeg", "image/jpeg"}, _
         {"jpg", "image/jpeg"}, _
         {"js", "application/x-javascript"}, _
         {"kar", "audio/midi"}, _
         {"latex", "application/x-latex"}, _
         {"lha", "application/octet-stream"}, _
         {"lzh", "application/octet-stream"}, _
         {"m3u", "audio/x-mpegurl"}, _
         {"m4a", "audio/mp4a-latm"}, _
         {"m4b", "audio/mp4a-latm"}, _
         {"m4p", "audio/mp4a-latm"}, _
         {"m4u", "video/vnd.mpegurl"}, _
         {"m4v", "video/x-m4v"}, _
         {"mac", "image/x-macpaint"}, _
         {"man", "application/x-troff-man"}, _
         {"mathml", "application/mathml+xml"}, _
         {"me", "application/x-troff-me"}, _
         {"mesh", "model/mesh"}, _
         {"mid", "audio/midi"}, _
         {"midi", "audio/midi"}, _
         {"mif", "application/vnd.mif"}, _
         {"mov", "video/quicktime"}, _
         {"movie", "video/x-sgi-movie"}, _
         {"mp2", "audio/mpeg"}, _
         {"mp3", "audio/mpeg"}, _
         {"mp4", "video/mp4"}, _
         {"mpe", "video/mpeg"}, _
         {"mpeg", "video/mpeg"}, _
         {"mpg", "video/mpeg"}, _
         {"mpga", "audio/mpeg"}, _
         {"ms", "application/x-troff-ms"}, _
         {"msh", "model/mesh"}, _
         {"mxu", "video/vnd.mpegurl"}, _
         {"nc", "application/x-netcdf"}, _
         {"oda", "application/oda"}, _
         {"ogg", "application/ogg"}, _
         {"pbm", "image/x-portable-bitmap"}, _
         {"pct", "image/pict"}, _
         {"pdb", "chemical/x-pdb"}, _
         {"pdf", "application/pdf"}, _
         {"pgm", "image/x-portable-graymap"}, _
         {"pgn", "application/x-chess-pgn"}, _
         {"pic", "image/pict"}, _
         {"pict", "image/pict"}, _
         {"png", "image/png"}, _
         {"pnm", "image/x-portable-anymap"}, _
         {"pnt", "image/x-macpaint"}, _
         {"pntg", "image/x-macpaint"}, _
         {"ppm", "image/x-portable-pixmap"}, _
         {"ppt", "application/"}, _
         {"ps", "application/postscript"}, _
         {"qt", "video/quicktime"}, _
         {"qti", "image/x-quicktime"}, _
         {"qtif", "image/x-quicktime"}, _
         {"ra", "audio/x-pn-realaudio"}, _
         {"ram", "audio/x-pn-realaudio"}, _
         {"ras", "image/x-cmu-raster"}, _
         {"rdf", "application/rdf+xml"}, _
         {"rgb", "image/x-rgb"}, _
         {"rm", "application/vnd.rn-realmedia"}, _
         {"roff", "application/x-troff"}, _
         {"rtf", "text/rtf"}, _
         {"rtx", "text/richtext"}, _
         {"sgm", "text/sgml"}, _
         {"sgml", "text/sgml"}, _
         {"sh", "application/x-sh"}, _
         {"shar", "application/x-shar"}, _
         {"silo", "model/mesh"}, _
         {"sit", "application/x-stuffit"}, _
         {"skd", "application/x-koan"}, _
         {"skm", "application/x-koan"}, _
         {"skp", "application/x-koan"}, _
         {"skt", "application/x-koan"}, _
         {"smi", "application/smil"}, _
         {"smil", "application/smil"}, _
         {"snd", "audio/basic"}, _
         {"so", "application/octet-stream"}, _
         {"spl", "application/x-futuresplash"}, _
         {"src", "application/x-wais-source"}, _
         {"sv4cpio", "application/x-sv4cpio"}, _
         {"sv4crc", "application/x-sv4crc"}, _
         {"svg", "image/svg+xml"}, _
         {"swf", "application/x-shockwave-flash"}, _
         {"t", "application/x-troff"}, _
         {"tar", "application/x-tar"}, _
         {"tcl", "application/x-tcl"}, _
         {"tex", "application/x-tex"}, _
         {"texi", "application/x-texinfo"}, _
         {"texinfo", "application/x-texinfo"}, _
         {"tif", "image/tiff"}, _
         {"tiff", "image/tiff"}, _
         {"tr", "application/x-troff"}, _
         {"tsv", "text/tab-separated-values"}, _
         {"txt", "text/plain"}, _
         {"ustar", "application/x-ustar"}, _
         {"vcd", "application/x-cdlink"}, _
         {"vrml", "model/vrml"}, _
         {"vxml", "application/voicexml+xml"}, _
         {"wav", "audio/x-wav"}, _
         {"wbmp", "image/vnd.wap.wbmp"}, _
         {"wbmxl", "application/vnd.wap.wbxml"}, _
         {"wml", "text/vnd.wap.wml"}, _
         {"wmlc", "application/vnd.wap.wmlc"}, _
         {"wmls", "text/vnd.wap.wmlscript"}, _
         {"wmlsc", "application/vnd.wap.wmlscriptc"}, _
         {"wrl", "model/vrml"}, _
         {"xbm", "image/x-xbitmap"}, _
         {"xht", "application/xhtml+xml"}, _
         {"xhtml", "application/xhtml+xml"}, _
         {"xls", "application/"}, _
         {"xml", "application/xml"}, _
         {"xpm", "image/x-xpixmap"}, _
         {"xsl", "application/xml"}, _
         {"xslt", "application/xslt+xml"}, _
         {"xul", "application/vnd.mozilla.xul+xml"}, _
         {"xwd", "image/x-xwindowdump"}, _
         {"xyz", "chemical/x-xyz"}, _
         {"zip", "application/zip"} _

Angularjs error Unknown provider

Make sure you are loading those modules ( and myApp.directives) as dependencies of your main app module, like this:

angular.module('myApp', ['myApp.directives', '']);


How can I do time/hours arithmetic in Google Spreadsheet?

In an fresh spreadsheet with 36:00:00 entered in A1 and 3:00:00 entered in B1 then:


say in C1 returns 12.

Why won't eclipse switch the compiler to Java 8?

First install the JDK1.8 set to Path Open Eclipse and Oper Eclipse Market Place option. Search for jdk 1.8 for kepler Install the required plugin. Restart the eclipse. Change compiler level to 1.8 from preferences. If still there is an error then click on the file and change the compiler setting explicitly to Jdk 1.8

How do I make a simple crawler in PHP?

In it's simplest form:

function crawl_page($url, $depth = 5) {
    if($depth > 0) {
        $html = file_get_contents($url);

        preg_match_all('~<a.*?href="(.*?)".*?>~', $html, $matches);

        foreach($matches[1] as $newurl) {
            crawl_page($newurl, $depth - 1);

        file_put_contents('results.txt', $newurl."\n\n".$html."\n\n", FILE_APPEND);

crawl_page('', 5);

That function will get contents from a page, then crawl all found links and save the contents to 'results.txt'. The functions accepts an second parameter, depth, which defines how long the links should be followed. Pass 1 there if you want to parse only links from the given page.

Initialize value of 'var' in C# to null

var variables still have a type - and the compiler error message says this type must be established during the declaration.

The specific request (assigning an initial null value) can be done, but I don't recommend it. It doesn't provide an advantage here (as the type must still be specified) and it could be viewed as making the code less readable:

var x = (String)null;

Which is still "type inferred" and equivalent to:

String x = null;

The compiler will not accept var x = null because it doesn't associate the null with any type - not even Object. Using the above approach, var x = (Object)null would "work" although it is of questionable usefulness.

Generally, when I can't use var's type inference correctly then

  1. I am at a place where it's best to declare the variable explicitly; or
  2. I should rewrite the code such that a valid value (with an established type) is assigned during the declaration.

The second approach can be done by moving code into methods or functions.

How to get the row number from a datatable?

Why don't you try this

for(int i=0; i < dt.Rows.Count; i++)
  // u can use here the i

"dd/mm/yyyy" date format in excel through vba

Your issue is with attempting to change your month by adding 1. 1 in date serials in Excel is equal to 1 day. Try changing your month by using the following:

NewDate = Format(DateAdd("m",1,StartDate),"dd/mm/yyyy")

How to create JSON object using jQuery

Nested JSON object

var data = {
            type: 'success', note:'Updated successfully',

You can parse this data.view.type and data.view.note

JSON Object and inside Array

var data = {
          view: [ 
                {type: 'success', note:'updated successfully'}

You can parse this data.view[0].type and data.view[0].note

How to make a local variable (inside a function) global

If you need access to the internal states of a function, you're possibly better off using a class. You can make a class instance behave like a function by making it a callable, which is done by defining __call__:

class StatefulFunction( object ):
    def __init__( self ):
        self.public_value = 'foo'

    def __call__( self ):
        return self.public_value

>> f = StatefulFunction()
>> f()
>> f.public_value = 'bar'
>> f()

Phone: numeric keyboard for text input

try this:

$(document).ready(function() {
    $(document).find('input[type=number]').attr('type', 'tel');


grep a tab in UNIX

use gawk, set the field delimiter to tab (\t) and check for number of fields. If more than 1, then there is/are tabs

awk -F"\t" 'NF>1' file

Getting the actual usedrange

What sort of button, neither a Forms Control nor an ActiveX control should affect the used range.

It is a known problem that excel does not keep track of the used range very well. Any reference to the used range via VBA will reset the value to the current used range. So try running this sub procedure:

Sub ResetUsedRng()
End Sub 

Failing that you may well have some formatting hanging round. Try clearing/deleting all the cells after your last row.

Regarding the above also see:

Excel Developer Tip

Another method to find the last used cell:

    Dim rLastCell As Range

    Set rLastCell = ActiveSheet.Cells.Find(What:="*", After:=.Cells(1, 1), LookIn:=xlFormulas, LookAt:= _
    xlPart, SearchOrder:=xlByRows, SearchDirection:=xlPrevious, MatchCase:=False)

Change the search direction to find the first used cell.

How to get names of enum entries?

My Enum is like this:

export enum UserSorting {
    SortByFullName = "Sort by FullName", 
    SortByLastname = "Sort by Lastame", 
    SortByEmail = "Sort by Email", 
    SortByRoleName = "Sort by Role", 
    SortByCreatedAt = "Sort by Creation date", 
    SortByCreatedBy = "Sort by Author", 
    SortByUpdatedAt = "Sort by Edit date", 
    SortByUpdatedBy = "Sort by Editor", 

so doing this return undefined:


To resolve this issue, I choose another way to do it using a Pipe:

import { Pipe, PipeTransform } from '@angular/core';

    name: 'enumKey'
export class EnumKeyPipe implements PipeTransform {

  transform(value, args: string[] = null): any {
    let enumValue = args[0];
    var keys = Object.keys(value);
    var values = Object.values(value);
    for (var i = 0; i < keys.length; i++) {
      if (values[i] == enumValue) {
        return keys[i];
    return null;

And to use it:

return this.enumKeyPipe.transform(UserSorting, [UserSorting.SortByUpdatedAt]);

How can I close a Twitter Bootstrap popover with a click from anywhere (else) on the page?

I found this to be a modified solution of pbaron's suggestion above, because his solution activated the popover('hide') on all elements with class 'popup-marker'. However, when you're using popover() for html content instead of the data-content, as I'm doing below, any clicks inside that html popup actually activate the popover('hide'), which promptly closes the window. This method below iterates through each .popup-marker element and discovers first if the parent is related to the .popup-marker's id that was clicked, and if so then does not hide it. All other divs are hidden...

            $('html').click(function(e) {
                // this is my departure from pbaron's code above
                // $('.popup-marker').popover('hide');
                $('.popup-marker').each(function() {
                    if ($('.popup-marker').attr('id')!=($(this).attr('id'))) {

                html: true,
                // this is where I'm setting the html for content from a nearby hidden div with id="html-"+clicked_div_id
                content: function() { return $('#html-'+$(this).attr('id')).html(); },
                trigger: 'manual'
            }).click(function(e) {

Access denied for user 'homestead'@'localhost' (using password: YES)

just change these things in the .env file of your root folder.


It worked for me.

Get string character by index - Java

None of the proposed answers works for surrogate pairs used to encode characters outside of the Unicode Basic Multiligual Plane.

Here is an example using three different techniques to iterate over the "characters" of a string (incl. using Java 8 stream API). Please notice this example includes characters of the Unicode Supplementary Multilingual Plane (SMP). You need a proper font to display this example and the result correctly.

// String containing characters of the Unicode 
// Supplementary Multilingual Plane (SMP)
// In that particular case, hieroglyphs.
String str = "The quick brown  jumps over the lazy ";

Iterate of chars

The first solution is a simple loop over all char of the string:

/* 1 */
        "\n\nUsing char iterator (do not work for surrogate pairs !)");
for (int pos = 0; pos < str.length(); ++pos) {
    char c = str.charAt(pos);
    System.out.printf("%s ", Character.toString(c));
    //                       ^^^^^^^^^^^^^^^^^^^^^
    //                   Convert to String as per OP request

Iterate of code points

The second solution uses an explicit loop too, but accessing individual code points with codePointAt and incrementing the loop index accordingly to charCount:

/* 2 */
        "\n\nUsing Java 1.5 codePointAt(works as expected)");
for (int pos = 0; pos < str.length();) {
    int cp = str.codePointAt(pos);

    char    chars[] = Character.toChars(cp);
    //                ^^^^^^^^^^^^^^^^^^^^^
    //               Convert to a `char[]`
    //               as code points outside the Unicode BMP
    //               will map to more than one Java `char`
    System.out.printf("%s ", new String(chars));
    //                       ^^^^^^^^^^^^^^^^^
    //               Convert to String as per OP request

    pos += Character.charCount(cp);
    //     ^^^^^^^^^^^^^^^^^^^^^^^
    //    Increment pos by 1 of more depending
    //    the number of Java `char` required to
    //    encode that particular codepoint.

Iterate over code points using the Stream API

The third solution is basically the same as the second, but using the Java 8 Stream API:

/* 3 */
        "\n\nUsing Java 8 stream (works as expected)");
    cp -> {
        char    chars[] = Character.toChars(cp);
        //                ^^^^^^^^^^^^^^^^^^^^^
        //               Convert to a `char[]`
        //               as code points outside the Unicode BMP
        //               will map to more than one Java `char`
        System.out.printf("%s ", new String(chars));
        //                       ^^^^^^^^^^^^^^^^^
        //               Convert to String as per OP request


When you run that test program, you obtain:

Using char iterator (do not work for surrogate pairs !)
T h e   q u i c k   b r o w n   ? ?   j u m p s   o v e r   t h e   l a z y   ? ? ? ? ? ? ? ? 

Using Java 1.5 codePointAt(works as expected)
T h e   q u i c k   b r o w n      j u m p s   o v e r   t h e   l a z y       

Using Java 8 stream (works as expected)
T h e   q u i c k   b r o w n      j u m p s   o v e r   t h e   l a z y       

As you can see (if you're able to display hieroglyphs properly), the first solution does not handle properly characters outside of the Unicode BMP. On the other hand, the other two solutions deal well with surrogate pairs.

How to check if input date is equal to today's date?

TodayDate = new Date();
if (TodayDate > AnotherDate) {} else{}

< = also works, Although with =, it might have to match the milliseconds.

How do I add the contents of an iterable to a set?

Use list comprehension.

Short circuiting the creation of iterable using a list for example :)

>>> x = [1, 2, 3, 4]
>>> k = x.__iter__()
>>> k
<listiterator object at 0x100517490>
>>> l = [y for y in k]
>>> l
[1, 2, 3, 4]
>>> z = Set([1,2])
>>> z.update(l)
>>> z
set([1, 2, 3, 4])

[Edit: missed the set part of question]

Could not load file or assembly 'System.Web.Http 4.0.0 after update from 2012 to 2013

    <assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" culture="neutral" />
    <bindingRedirect oldVersion="" newVersion="" />
    <assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
    <bindingRedirect oldVersion="" newVersion="" />

Is there a simple way to use button to navigate page as a link does in angularjs

Your ngClick is correct; you just need the right service. $location is what you're looking for. Check out the docs for the full details, but the solution to your specific question is this:

$location.path( '/new-page.html' );

The $location service will add the hash (#) if it's appropriate based on your current settings and ensure no page reload occurs.

You could also do something more flexible with a directive if you so chose:

.directive( 'goClick', function ( $location ) {
  return function ( scope, element, attrs ) {
    var path;

    attrs.$observe( 'goClick', function (val) {
      path = val;

    element.bind( 'click', function () {
      scope.$apply( function () {
        $location.path( path );

And then you could use it on anything:

<button go-click="/go/to/this">Click!</button>

There are many ways to improve this directive; it's merely to show what could be done. Here's a Plunker demonstrating it in action:

How do I create a view controller file after creating a new view controller?

To add new ViewController once you have have an existing ViewController, follow below step:

  1. Click on background of Main.storyboard.

  2. Search and select ViewController from object library at the utility window.

  3. Drag and drop it in background to create a new ViewController.

How to read one single line of csv data in Python?

To read only the first row of the csv file use next() on the reader object.

with open('some.csv', newline='') as f:
  reader = csv.reader(f)
  row1 = next(reader)  # gets the first line
  # now do something here 
  # if first row is the header, then you can do one more next() to get the next row:
  # row2 = next(f)

or :

with open('some.csv', newline='') as f:
  reader = csv.reader(f)
  for row in reader:
    # do something here with `row`