Programs & Examples On #Ocamlbuild

OCamlbuild is a generic build tool, that has built-in rules for building OCaml library and programs.

What is the difference between explicit and implicit cursors in Oracle?

An explicit cursor is one you declare, like:

CURSOR my_cursor IS

An implicit cursor is one created to support any in-line SQL you write (either static or dynamic).

Spring MVC - Why not able to use @RequestBody and @RequestParam together

It's too late to answer this question, but it could help for new readers, It seems version issues. I ran all these tests with spring 4.1.4 and found that the order of @RequestBody and @RequestParam doesn't matter.

  1. same as your result
  2. same as your result
  3. gave body= "name=abc", and name = "abc"
  4. Same as 3.
  5. body ="name=abc", name = "xyz,abc"
  6. same as 5.

Location of the android sdk has not been setup in the preferences in mac os?

Hope this helps:

Step 1.) Go to and download appropriate Eclipse version.

Step 2.) Extract downloaded zip file in appropriate location. In this tutorial, I have downloaded and installed it under program files.

Step 3.) Right click on eclipse.exe file and send shortcut to desktop.

Step 4.) Double click on eclipse shortcut from desktop and select appropriate location to create your workspace.

Step 5.) Navigate to Window > Preferences. This should open Preferences window.

Step 6.) On the left hand side page expend “Java” and click on “Installed JREs”

Step 7.) Click Add. It will open “Add JRE” dialog. Select “Standard VM” and click Next.

Step 8.) For “JRE home” select “Direcotry…”. This will open “Browse for folder” dialog. Select the location where your JDK is installed. NOTE: MAKE SURE THAT ITS x64 AS WELL, AS WE ARE USING 64-BIT VERSION OF ECLIPSE.

Step 9.) If you have selected proper location, it will show JDK version in JRE name and it will display “JRE system libraries”.

Step 10.) Click finish. Now your JDK is properly pointed as “Installed JREs”.

Step 11.) Select checkbox unchecked before name of your JDK name.

Click ok and you’re done. You are now using JDK as “Installed JREs”

Read complete procedure at below location.

Quickest way to clear all sheet contents VBA

The .Cells range isn't limited to ones that are being used, so your code is clearing the content of 1,048,576 rows and 16,384 columns - 17,179,869,184 total cells. That's going to take a while. Just clear the UsedRange instead:


Alternately, you can delete the sheet and re-add it:

Application.DisplayAlerts = False
Application.DisplayAlerts = True
Dim sheet As Worksheet
Set sheet = Sheets.Add
sheet.Name = "Zeros"

How to remove all duplicate items from a list

This should be faster and will preserve the original order:

seen = {}
new_list = [seen.setdefault(x, x) for x in my_list if x not in seen]

If you don't care about order, you can just:

new_list = list(set(my_list))

How to clear exisiting dropdownlist items when its content changes?

You should clear out your listbbox prior to binding:

  ' now set datasource and bind

equals vs Arrays.equals in Java

array1.equals(array2) is the same as array1 == array2, i.e. is it the same array. As @alf points out it's not what most people expect.

Arrays.equals(array1, array2) compares the contents of the arrays.

Similarly array.toString() may not be very useful and you need to use Arrays.toString(array).

How to increase Heap size of JVM

Java command line parameters

-Xms: initial heap size
-Xmx: Maximum heap size

if you are using Tomcat. Update CATALINA_OPTS environment variable

export CATALINA_OPTS=-Xms16m -Xmx256m;

Configure Log4net to write to multiple files

Use below XML configuration to configure logs into two or more files:

    <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
      <file value="logs\log.txt" />         
      <appendToFile value="true" /> 
      <rollingStyle value="Size" />
      <maxSizeRollBackups value="10" />
      <maximumFileSize value="10MB" />
      <staticLogFileName value="true" />
      <layout type="log4net.Layout.PatternLayout">           
        <conversionPattern value="%date [%thread] %level %logger - %message%newline" />
     <appender name="RollingLogFileAppender2" type="log4net.Appender.RollingFileAppender">
      <file value="logs\log1.txt" />         
      <appendToFile value="true" /> 
      <rollingStyle value="Size" />
      <maxSizeRollBackups value="10" />
      <maximumFileSize value="10MB" />
      <staticLogFileName value="true" />
      <layout type="log4net.Layout.PatternLayout">        
        <conversionPattern value="%date [%thread] %level %logger - %message%newline" />
      <level value="All" />
      <appender-ref ref="RollingLogFileAppender" />
     <logger additivity="false" name="RollingLogFileAppender2">
    <level value="All"/>
    <appender-ref ref="RollingLogFileAppender2" />

Above XML configuration logs into two different files. To get specific instance of logger programmatically:

ILog logger = log4net.LogManager.GetLogger ("RollingLogFileAppender2");

You can append two or more appender elements inside log4net root element for logging into multiples files.

More info about above XML configuration structure or which appender is best for your application, read details from below links:

Order of execution of tests in TestNG

Tests like unit tests? What for? Tests HAVE to be independant, otherwise.... you can not run a test individually. If they are independent, why even interfere? Plus - what is an "order" if you run them in multiple threads on multiple cores?

How do I extract a substring from a string until the second space is encountered?

string testString = "o1 1232.5467 1232.5467.........";

string secondItem = testString.Split(new char[]{' '}, 3)[1];

How to add additional libraries to Visual Studio project?

Without knowing your compiler, no one can give you specific, step by step instructions, but the basic procedure is as follows:

  1. Specify the path which should be searched in order to find the actual library (usually under Library Search Paths, Library Directories, etc. in the properties page)

  2. Under linker options, specify the actual name of the library. In VS, you would write Allegro.lib (or whatever it is), on Linux you usually just write Allegro (prefixes/suffixes are added automatically in most cases). This is usually under "Libraries->Input", just "Libraries", or something similar.

  3. Ensure that you have included the headers for the library and make sure that they can be found (similar process to that listed in step #1 and #2). If it is a static library, you should be good; if it's a DLL, you need to copy it in your project.

  4. Mash the build button.

jQuery if Element has an ID?

Like this:

var $aWithId = $('.parent a[id]');

Following OP's comment, test it like this:

if($aWithId.length) //or without using variable: if ($('.parent a[id]').length)

Will return all anchor tags inside elements with class parent which have an attribute ID specified

tsconfig.json: Build:No inputs were found in config file

I added the following in the root ( visual studio )

  "compilerOptions": {
    "allowJs": true,
    "noEmit": true,
    "module": "system",
    "noImplicitAny": true,
    "removeComments": true,
    "preserveConstEnums": true,
    "sourceMap": true
  "include": [
  "exclude": [
  "typeAcquisition": {
    "enable": true

Telegram Bot - how to get a group chat id?

Here is the sequence that worked for me after struggling for several hours:

Assume the bot name is my_bot.

1- Add the bot to the group.
Go to the group, click on group name, click on Add members, in the searchbox search for your bot like this: @my_bot, select your bot and click add.

2- Send a dummy message to the bot.
You can use this example: /my_id @my_bot
(I tried a few messages, not all the messages work. The example above works fine. Maybe the message should start with /)

3- Go to following url:
replace XXX:YYYY with your bot token

4- Look for "chat":{"id":-zzzzzzzzzz,
-zzzzzzzzzz is your chat id (with the negative sign).

5- Testing: You can test sending a message to the group with a curl:

curl -X POST "" -d "chat_id=-zzzzzzzzzz&text=my sample text"

If you miss step 2, there would be no update for the group you are looking for. Also if there are multiple groups, you can look for the group name in the response ("title":"group_name").

Hope this helps.

Wireshark vs Firebug vs Fiddler - pros and cons?

I use both Charles Proxy and Fiddler for my HTTP/HTTPS level debugging.

Pros of Charles Proxy:

  1. Handles HTTPS better (you get a Charles Certificate which you'd put in 'Trusted Authorities' list)
  2. Has more features like Load/Save Session (esp. useful when debugging multiple pages), Mirror a website (useful in caching assets and hence faster debugging), etc.
  3. As mentioned by jburgess, handles AMF.
  4. Displays JSON, XML and other kind of responses in a tree structure, making it easier to read. Displays images in image responses instead of binary data.

Cons of Charles Proxy:

  1. Cost :-)

PHP XML Extension: Not installed

You're close

sudo apt-get install php-xml

Then you need to restart apache so it takes effect

sudo service apache2 restart

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

Use SqlTableDependency. It is a c# component raising events when a record is changes. You can find others detail at:

It is similat to .NET SqlDependency except that SqlTableDependency raise events containing modified / deleted or updated database table values:

string conString = "data source=.;initial catalog=myDB;integrated security=True";

using(var tableDependency = new SqlTableDependency<Customers>(conString))
    tableDependency.OnChanged += TableDependency_Changed;

    Console.WriteLine("Waiting for receiving notifications...");
    Console.WriteLine("Press a key to stop");
void TableDependency_Changed(object sender, RecordChangedEventArgs<Customers> e)
    if (e.ChangeType != ChangeType.None)
        var changedEntity = e.Entity;
        Console.WriteLine("DML operation: " + e.ChangeType);
        Console.WriteLine("ID: " + changedEntity.Id);
        Console.WriteLine("Name: " + changedEntity.Name);
        Console.WriteLine("Surname: " + changedEntity.Surname);

pip installs packages successfully, but executables not found from command line

check your $PATH

tox has a command line mode:

audrey:tests jluc$ pip list | grep tox
tox (2.3.1)

where is it?

(edit: the 2.7 stuff doesn't matter much here, sub in any 3.x and pip's behaving pretty much the same way)

audrey:tests jluc$ which tox

and what's in my $PATH?

audrey:tests jluc$ echo $PATH

Notice the /opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin? That's what allows finding my pip-installed stuff

Now, to see where things are from Python, try doing this (substitute rosdep for tox).

>>> import tox
>>> tox.__file__

that prints out:


Now, cd to the directory right above lib in the above. Do you see a bin directory? Do you see rosdep in that bin? If so try adding the bin to your $PATH.

audrey:2.7 jluc$ cd /opt/local/Library/Frameworks/Python.framework/Versions/2.7
audrey:2.7 jluc$ ls -1



Getting the index of a particular item in array

The previous answers will only work if you know the exact value you are searching for - the question states that only a partial value is known.

Array.FindIndex(authors, author => author.Contains("xyz"));

This will return the index of the first item containing "xyz".

Change DataGrid cell colour based on values

Based on the answer by 'Cassio Borghi'. With this method, there is no need to change the XAML at all.

        DataGridTextColumn colNameStatus2 = new DataGridTextColumn();
        colNameStatus2.Header = "Status";
        colNameStatus2.MinWidth = 100;
        colNameStatus2.Binding = new Binding("Status");

        Style style = new Style(typeof(TextBlock));
        Trigger running = new Trigger() { Property = TextBlock.TextProperty, Value = "Running" };
        Trigger stopped = new Trigger() { Property = TextBlock.TextProperty, Value = "Stopped" };

        stopped.Setters.Add(new Setter() { Property = TextBlock.BackgroundProperty, Value = Brushes.Blue });
        running.Setters.Add(new Setter() { Property = TextBlock.BackgroundProperty, Value = Brushes.Green });


        colNameStatus2.ElementStyle = style;

        foreach (var Service in computerResult)
            var RowName = Service;  

What is the default access modifier in Java?

It depends on the context.

When it's within a class:

class example1 {

    int a = 10; // This is package-private (visible within package)

    void method1() // This is package-private as well.

When it's within a interface:

interface example2 {

    int b = 10; // This is public and static.
    void method2(); // This is public and abstract

How to obtain the chat_id of a private Telegram channel?

The option that I do is by using the popular Plus Messenger on Android. The play store link is:

You can click on the Channel and in Channel info below the group name, you can find Channel Id.

Supergroup and Channel Ids will looks like 1068773197 on plus messenger. For your usage on API, you can prefix -100 which would make it -1001068773197.

What is the difference between float and double?

When using floating point numbers you cannot trust that your local tests will be exactly the same as the tests that are done on the server side. The environment and the compiler are probably different on you local system and where the final tests are run. I have seen this problem many times before in some TopCoder competitions especially if you try to compare two floating point numbers.

How do I setup a SSL certificate for an express.js server?

I was able to get SSL working with the following boilerplate code:

var fs = require('fs'),
    http = require('http'),
    https = require('https'),
    express = require('express');

var port = 8000;

var options = {
    key: fs.readFileSync('./ssl/privatekey.pem'),
    cert: fs.readFileSync('./ssl/certificate.pem'),

var app = express();

var server = https.createServer(options, app).listen(port, function(){
  console.log("Express server listening on port " + port);

app.get('/', function (req, res) {
    res.end("hello world\n");

Table with fixed header and fixed column on pure css

After two days fighting with Internet Explorer 9 + Chrome + Firefox (Windows) and Safari (Mac), I have found a system that is

  • Compatible with all these browsers
  • Without using javascript
  • Using only une div and one table
  • Fixed header and footer (Except for IE), with scrollable body. Header and body with same column widths

Result: enter image description here


      <th class="nombre"><%= f.label :cost_center %></th>
      <th class="cabecera cc">Personal</th>
      <th class="cabecera cc">Dpto</th>
    <% @cost_centers.each do |cc| %>
      <td class="nombre"><%= cc.nombre_corto %></td>
      <td class="cc"><%= cc.cacentrocoste %></td>
      <td class="cc"><%= cc.cacentrocoste_dpto %></td>
    <% end %>
      <td colspan="3"><a href="#">Mostrar mas usuarios</a></td>


  margin-bottom: 2px;
  float: right;
  display: inline-block;
  overflow-y: auto;
  overflow-x: hidden;

div.cost_center label { 

div.cost_center table{
  border-collapse: collapse; 

div.cost_center table tr{
div.cost_center th{

div.cost_center table tbody{
  display: block;
  overflow: auto;

div.cost_center table thead{

div.cost_center table tfoot{
div.cost_center table tfoot td{
div.cost_center .cc{
  text-align: center; 
  border: 1px solid #999;

div.cost_center .nombre{
div.cost_center tbody .nombre{
  border: 1px solid #999;

div.cost_center table tfoot td{
 border: 1px solid #999; 

div.cost_center table th, 
div.cost_center table td { 
  padding: 2px;
  vertical-align: middle; 

div.cost_center table tbody td {
  white-space: normal;
  font:  .8em/1.4em Verdana, sans-serif;
  color: #000;
  background-color: white;
div.cost_center table th.cabecera { 
  font:  0.8em/1.4em Verdana, sans-serif;
  color: #000;
  background-color: #FFEAB5;

What is the difference between NULL, '\0' and 0?

A byte with a value of 0x00 is, on the ASCII table, the special character called NUL or NULL. In C, since you shouldn't embed control characters in your source code, this is represented in C strings with an escaped 0, i.e., \0.

But a true NULL is not a value. It is the absence of a value. For a pointer, it means the pointer has nothing to point to. In a database, it means there is no value in a field (which is not the same thing as saying the field is blank, 0, or filled with spaces).

The actual value a given system or database file format uses to represent a NULL isn't necessarily 0x00.

Range with step of type float

One explanation might be floating point rounding issues. For example, if you could call

range(0, 0.4, 0.1)

you might expect an output of

[0, 0.1, 0.2, 0.3]

but you in fact get something like

[0, 0.1, 0.2000000001, 0.3000000001]

due to rounding issues. And since range is often used to generate indices of some sort, it's integers only.

Still, if you want a range generator for floats, you can just roll your own.

def xfrange(start, stop, step):
    i = 0
    while start + i * step < stop:
        yield start + i * step
        i += 1

Create table with jQuery - append

Following is done for multiple file uploads using jquery:

File input button:

 <input type="file" name="uploadFiles" id="uploadFiles" multiple="multiple" class="input-xlarge" onchange="getFileSizeandName(this);"/> 

Displaying File name and File size in a table:

<div id="uploadMultipleFilediv">
<table id="uploadTable" class="table table-striped table-bordered table-condensed"></table></div>

Javascript for getting the file name and file size:

function getFileSizeandName(input)
    var select = $('#uploadTable');
    var totalsizeOfUploadFiles = "";
    for(var i =0; i<input.files.length; i++)
        var filesizeInBytes = input.files[i].size; // file size in bytes
        var filesizeInMB = (filesizeInBytes / (1024*1024)).toFixed(2); // convert the file size from bytes to mb
        var filename = input.files[i].name;
        totalsizeOfUploadFiles = totalsizeOfUploadFiles+filesizeInMB;
        //alert("File name is : "+filename+" || size : "+filesizeInMB+" MB || size : "+filesizeInBytes+" Bytes");               

How to create a string with format?

First read Official documentation for Swift language.

Answer should be



1) Any floating point value by default double

 var myVal = 5.2 // its double by default;

-> If you want to display floating point value then you need to explicitly define such like a

     var myVal:Float = 5.2 // now its float value;

This is far more clear.

How to create .pfx file from certificate and private key?

You need to use the makecert tool.

Open a command prompt as admin and type the following:

makecert -sky exchange -r -n "CN=<CertificateName>" -pe -a sha1 -len 2048 -ss My "<CertificateName>.cer"

Where <CertifcateName> = the name of your cert to create.

Then you can open the Certificate Manager snap-in for the management console by typing certmgr.msc in the Start menu, click personal > certificates > and your cert should be available.

Here is an article.

Convert HTML5 into standalone Android App

You could use PhoneGap.

This has the benefit of being a cross-platform solution. Be warned though that you may need to pay subscription fees. The simplest solution is to just embed a WebView as detailed in @Enigma's answer.

How to programmatically log out from Facebook SDK 3.0 without using Facebook login/logout button?

Since Facebook's Android SDK v4.0 you need to execute the following:


This is not sufficient. This will simply clear cached access token and profile so that AccessToken.getCurrentAccessToken() and Profile.getCurrentProfile() will now become null.

To completely logout you need to revoke permissions and then call LoginManager.getInstance().logOut();. To revoke permission execute following graph API -

    GraphRequest delPermRequest = new GraphRequest(AccessToken.getCurrentAccessToken(), "/{user-id}/permissions/", null, HttpMethod.DELETE, new GraphRequest.Callback() {
        public void onCompleted(GraphResponse graphResponse) {
                FacebookRequestError error =graphResponse.getError();
                    Log.e(TAG, error.toString());
                }else {
    Log.d(TAG,"Executing revoke permissions with graph path" + delPermRequest.getGraphPath());

IIs Error: Application Codebehind=“Global.asax.cs” Inherits=“nadeem.MvcApplication”

You can change it by editing Globas.asax file (not Global.asax.cs). Find it in app folder in windows explorer then edit

<%@ Application Codebehind="Global.asax.cs" Inherits="YourAppName.Global" Language="C#" %>


<%@ Application Codebehind="Global.asax.cs" Inherits="YourAppName.MvcApplication" Language="C#" %>

How to resize an image with OpenCV2.0 and Python2.6

Example doubling the image size

There are two ways to resize an image. The new size can be specified:

  1. Manually;

    height, width = src.shape[:2]

    dst = cv2.resize(src, (2*width, 2*height), interpolation = cv2.INTER_CUBIC)

  2. By a scaling factor.

    dst = cv2.resize(src, None, fx = 2, fy = 2, interpolation = cv2.INTER_CUBIC), where fx is the scaling factor along the horizontal axis and fy along the vertical axis.

To shrink an image, it will generally look best with INTER_AREA interpolation, whereas to enlarge an image, it will generally look best with INTER_CUBIC (slow) or INTER_LINEAR (faster but still looks OK).

Example shrink image to fit a max height/width (keeping aspect ratio)

import cv2

img = cv2.imread('YOUR_PATH_TO_IMG')

height, width = img.shape[:2]
max_height = 300
max_width = 300

# only shrink if img is bigger than required
if max_height < height or max_width < width:
    # get scaling factor
    scaling_factor = max_height / float(height)
    if max_width/float(width) < scaling_factor:
        scaling_factor = max_width / float(width)
    # resize image
    img = cv2.resize(img, None, fx=scaling_factor, fy=scaling_factor, interpolation=cv2.INTER_AREA)

cv2.imshow("Shrinked image", img)
key = cv2.waitKey()

Using your code with cv2

import cv2 as cv

im = cv.imread(path)

height, width = im.shape[:2]

thumbnail = cv.resize(im, (round(width / 10), round(height / 10)), interpolation=cv.INTER_AREA)

cv.imshow('exampleshq', thumbnail)

Skip the headers when editing a csv file using Python

Your reader variable is an iterable, by looping over it you retrieve the rows.

To make it skip one item before your loop, simply call next(reader, None) and ignore the return value.

You can also simplify your code a little; use the opened files as context managers to have them closed automatically:

with open("tmob_notcleaned.csv", "rb") as infile, open("tmob_cleaned.csv", "wb") as outfile:
   reader = csv.reader(infile)
   next(reader, None)  # skip the headers
   writer = csv.writer(outfile)
   for row in reader:
       # process each row

# no need to close, the files are closed automatically when you get to this point.

If you wanted to write the header to the output file unprocessed, that's easy too, pass the output of next() to writer.writerow():

headers = next(reader, None)  # returns the headers or `None` if the input is empty
if headers:

How to download dependencies in gradle

There is no task to download dependencies; they are downloaded on demand. To learn how to manage dependencies with Gradle, see "Chapter 8. Dependency Management Basics" in the Gradle User Guide.

Styling the arrow on bootstrap tooltips

For styling each directional arrows(left, right,top and bottom), we have to select each arrow using CSS attribute selector and then style them individually.

Trick: Top arrow must have border color only on top side and transparent on other 3 sides. Other directional arrows also need to be styled this way.

click here for Working Jsfiddle Link

Here is the simple CSS,

.tooltip-inner { background-color:#8447cf;}

[data-placement="top"] + .tooltip > .tooltip-arrow { border-top-color: #8447cf;}

[data-placement="right"] + .tooltip > .tooltip-arrow { border-right-color: #8447cf;}

[data-placement="bottom"] + .tooltip > .tooltip-arrow {border-bottom-color: #8447cf;}

[data-placement="left"] + .tooltip > .tooltip-arrow {border-left-color: #8447cf; }

Javascript call() & apply() vs bind()?

They all attach this into function (or object) and the difference is in the function invocation (see below).

call attaches this into function and executes the function immediately:

var person = {  
  name: "James Smith",
  hello: function(thing) {
    console.log( + " says hello " + thing);

person.hello("world");  // output: "James Smith says hello world"{ name: "Jim Smith" }, "world"); // output: "Jim Smith says hello world"

bind attaches this into function and it needs to be invoked separately like this:

var person = {  
  name: "James Smith",
  hello: function(thing) {
    console.log( + " says hello " + thing);

person.hello("world");  // output: "James Smith says hello world"
var helloFunc = person.hello.bind({ name: "Jim Smith" });
helloFunc("world");  // output: Jim Smith says hello world"

or like this:

var helloFunc = person.hello.bind({ name: "Jim Smith" }, "world");
helloFunc();  // output: Jim Smith says hello world"

apply is similar to call except that it takes an array-like object instead of listing the arguments out one at a time:

function personContainer() {
  var person = {  
     name: "James Smith",
     hello: function() {
       console.log( + " says hello " + arguments[1]);
  person.hello.apply(person, arguments);
personContainer("world", "mars"); // output: "James Smith says hello mars", note: arguments[0] = "world" , arguments[1] = "mars"                                     

How to use MapView in android using google map V2?

More complete sample from here and here.

Or you can check out my layout sample. p.s no need to put API key in the map view.

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

<LinearLayout xmlns:android=""


    <ListView android:id="@+id/nearby_lv"


How to save username and password in Git?

In that case you need git credential helper to tell git to remember your GitHub password and username by using following command line :

git config --global credential.helper wincred 

and if you are using repo using SSH key then you need SSH key to authenticate.

The type WebMvcConfigurerAdapter is deprecated

In Spring every request will go through the DispatcherServlet. To avoid Static file request through DispatcherServlet(Front contoller) we configure MVC Static content.

Spring 3.1. introduced the ResourceHandlerRegistry to configure ResourceHttpRequestHandlers for serving static resources from the classpath, the WAR, or the file system. We can configure the ResourceHandlerRegistry programmatically inside our web context configuration class.

  • we have added the /js/** pattern to the ResourceHandler, lets include the foo.js resource located in the webapp/js/ directory
  • we have added the /resources/static/** pattern to the ResourceHandler, lets include the foo.html resource located in the webapp/resources/ directory
public class StaticResourceConfiguration implements WebMvcConfigurer {

    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        System.out.println("WebMvcConfigurer - addResourceHandlers() function get loaded...");

            .addResolver(new GzipResourceResolver())
            .addResolver(new PathResourceResolver());

XML Configuration

<mvc:annotation-driven />
  <mvc:resources mapping="/staticFiles/path/**" location="/staticFilesFolder/js/"

Spring Boot MVC Static Content if the file is located in the WAR’s webapp/resources folder.


How to get hostname from IP (Linux)?

Another simple way I found for using in LAN is

ssh [username@ip] uname -n

If you need to login command line will be

sshpass -p "[password]" ssh [username@ip] uname -n

Uncaught TypeError: Cannot read property 'length' of undefined

console.log(typeof json_data !== 'undefined'
    ? json_data.length : 'There is no spoon.');

...or more simply...

console.log(json_data ? json_data.length : 'json_data is null or undefined');

`getchar()` gives the same output as the input string

Strings, by C definition, are terminated by '\0'. You have no "C strings" in your program.

Your program reads characters (buffered till ENTER) from the standard input (the keyboard) and writes them back to the standard output (the screen). It does this no matter how many characters you type or for how long you do this.

To stop the program you have to indicate that the standard input has no more data (huh?? how can a keyboard have no more data?).

You simply press Ctrl+D (Unix) or Ctrl+Z (Windows) to pretend the file has reached its end.
Ctrl+D (or Ctrl+Z) are not really characters in the C sense of the word.

If you run your program with input redirection, the EOF is the actual end of file, not a make belief one
./a.out < source.c

Ordering by the order of values in a SQL IN() clause

Give this a shot:

SELECT name, description, ...
    (SELECT id FROM table1 WHERE...)
    (SELECT display_order FROM table1 WHERE...),
    (SELECT name FROM table1 WHERE...)

The WHEREs will probably take a little tweaking to get the correlated subqueries working properly, but the basic principle should be sound.

How to synchronize a static variable among threads running different instances of a class in Java?

If you're simply sharing a counter, consider using an AtomicInteger or another suitable class from the java.util.concurrent.atomic package:

public class Test {

    private final static AtomicInteger count = new AtomicInteger(0); 

    public void foo() {  

How can I get the height and width of an uiimage?

let imageView: UIImageView = //this is your existing imageView

let imageViewHeight: CGFloat = imageView.frame.height

let imageViewWidth: CGFloat = imageView.frame.width

Git keeps asking me for my ssh key passphrase

If you are not using GitBash and are on Windows - you need to start your ssh-agent using this command


If your ssh agent is not set up, you can open PowerShell as admin and set it to manual mode

Get-Service -Name ssh-agent | Set-Service -StartupType Manual

How do you set the EditText keyboard to only consist of numbers on Android?

I think you used somehow the right way to show the number only on the keyboard so better try the given line with xml in your edit text and it will work perfectly so here the code is-


In case any doubt you can again ask to me i'll try to completely sort out your problem. Thanks

How to get the name of the current Windows user in JavaScript

Working for me on IE:

<script type="text/javascript">
  var WinNetwork = new ActiveXObject("WScript.Network");

...but ActiveX controls needs to be on in security settings.

Difference between java.lang.RuntimeException and java.lang.Exception

Exceptions are a good way to handle unexpected events in your application flow. RuntimeException are unchecked by the Compiler but you may prefer to use Exceptions that extend Exception Class to control the behaviour of your api clients as they are required to catch errors for them to compile. Also forms good documentation.

If want to achieve clean interface use inheritance to subclass the different types of exception your application has and then expose the parent exception.

A keyboard shortcut to comment/uncomment the select text in Android Studio

You can also use regions. See

Select a block of code, then press Code > Surround With... (Ctrl + Alt + T) and select "region...endregion Comments" (2).

Import Maven dependencies in IntelliJ IDEA

Reimport the project. If you install maven plugin you can use this.

Right click on the project -> Maven -> Reimport

How do search engines deal with AngularJS applications?

Angular's own website serves simplified content to search engines:

Say your Angular app is consuming a Node.js/Express-driven JSON api, like /api/path/to/resource. Perhaps you could redirect any requests with ?_escaped_fragment_ to /api/path/to/resource.html, and use content negotiation to render an HTML template of the content, rather than return the JSON data.

The only thing is, your Angular routes would need to match 1:1 with your REST API.

EDIT: I'm realizing that this has the potential to really muddy up your REST api and I don't recommend doing it outside of very simple use-cases where it might be a natural fit.

Instead, you can use an entirely different set of routes and controllers for your robot-friendly content. But then you're duplicating all of your AngularJS routes and controllers in Node/Express.

I've settled on generating snapshots with a headless browser, even though I feel that's a little less-than-ideal.

Download a file from HTTPS using download.file()

I've succeed with the following code:

url = ""
x = read.csv(file=url)

Note that I've changed the protocol from https to http, since the first one doesn't seem to be supported in R.

li:before{ content: "¦"; } How to Encode this Special Character as a Bullit in an Email Stationery?

Lea's converter is no longer available. I just used this converter


  1. Enter the Unicode decimal version such as 8226 in the tool's green input field.
  2. Press Dec code points
  3. See the result in the box Unicode U+hex notation (eg U+2022)
  4. Use it in your CSS. Eg content: '\2022'

ps. I have no connection with the web site.

Adding new line of data to TextBox

I find this method saves a lot of typing, and prevents a lot of typos.

string nl = "\r\n";

txtOutput.Text = "First line" + nl + "Second line" + nl + "Third line";

Getting the absolute path of the executable, using C#?

On my side, I used, with a form application:

String Directory = System.Windows.Forms.Application.StartupPath;

it takes the application startup path.

Type definition in object literal in TypeScript

// Use ..

const Per = {
  name: 'HAMZA',
  age: 20,
  coords: {
    tele: '09',
    lan: '190'
  setAge(age: Number): void {
    this.age = age;
  getAge(): Number {
    return age;
const { age, name }: { age: Number; name: String } = Per;
const {
  coords: { tele, lan }
}: { coords: { tele: String; lan: String } } = Per;


SQL Server query to find all permissions/access for all users in a database

Here is my version, adapted from others. I spent 30 minutes just now trying to remember how I came up with this, and @Jeremy 's answer seems to be the core inspiration. I didn't want to update Jeremy's answer, just in case I introduced bugs, so I am posting my version of it here.

I suggest pairing the full script with some inspiration taken from Kenneth Fisher's T-SQL Tuesday: What Permissions Does a Specific User Have?: This will allow you to answer compliance/audit questions bottom-up, as opposed to top-down.

EXECUTE AS LOGIN = '<loginname>'

SELECT AS GroupNames
FROM sys.login_token token
JOIN sys.server_principals grp
    ON token.sid = grp.sid
WHERE token.[type] = 'WINDOWS GROUP'
  AND grp.[type] = 'G'


To understand what this covers, consider Contoso\DB_AdventureWorks_Accounting Windows AD Group with member Contoso\John.Doe. John.Doe authenticates to AdventureWorks via server_principal Contoso\DB_AdventureWorks_Logins Windows AD Group. If someone asks you, "What permissions does John.Doe have?", you cannot answer that question with just the below script. You need to then iterate through each row returned by the below script and join it to the above script. (You may also need to normalize for stale name values via looking up the SID in your Active Directory provider.)

Here is the script, without incorporating such reverse look-up logic.


--Script source found at :
Security Audit Report
1) List all access provisioned to a sql user or windows user/group directly 
2) List all access provisioned to a sql user or windows user/group through a database or application role
3) List all access provisioned to the public role

Columns Returned:
UserName         : SQL or Windows/Active Directory user account.  This could also be an Active Directory group.
UserType         : Value will be either 'SQL User' or 'Windows User'.  This reflects the type of user defined for the 
                  SQL Server user account.
PrinciaplUserName: if UserName is not blank, then UserName else DatabaseUserName
PrincipalType    : Possible values are 'SQL User', 'Windows User', 'Database Role', 'Windows Group'
DatabaseUserName : Name of the associated user as defined in the database user account.  The database user may not be the
                   same as the server user.
Role             : The role name.  This will be null if the associated permissions to the object are defined at directly
                   on the user account, otherwise this will be the name of the role that the user is a member of.
PermissionType   : Type of permissions the user/role has on an object. Examples could include CONNECT, EXECUTE, SELECT
                   This value may not be populated for all roles.  Some built in roles have implicit permission
PermissionState  : Reflects the state of the permission type, examples could include GRANT, DENY, etc.
                   This value may not be populated for all roles.  Some built in roles have implicit permission
ObjectType       : Type of object the user/role is assigned permissions on.  Examples could include USER_TABLE, 
                   This value may not be populated for all roles.  Some built in roles have implicit permission
ObjectName       : Name of the object that the user/role is assigned permissions on.  
                   This value may not be populated for all roles.  Some built in roles have implicit permission
ColumnName       : Name of the column of the object that the user/role is assigned permissions on. This value
                   is only populated if the object is a table, view or a table value function.                 

DECLARE @HideDatabaseDiagrams BIT = 1;

--List all access provisioned to a sql user or windows user/group directly 
    [UserName] = CASE dbprinc.[type] 
                    WHEN 'S' THEN dbprinc.[name] -- SQL User
                    WHEN 'U' THEN sprinc.[name] -- Windows User
                    WHEN 'R' THEN NULL -- Database Role
                    WHEN 'G' THEN NULL -- Windows Group
                    ELSE NULL
    [UserType] = CASE dbprinc.[type]
                    WHEN 'S' THEN 'SQL User'
                    WHEN 'U' THEN 'Windows User'
                    WHEN 'R' THEN NULL -- Database Role
                    WHEN 'G' THEN NULL -- Windows Group
                    ELSE dbprinc.[type]
    [PrincipalUserName] = COALESCE(
                    CASE dbprinc.[type]
                        WHEN 'S' THEN dbprinc.[name] -- SQL User
                        WHEN 'U' THEN sprinc.[name] -- Windows User
                        WHEN 'R' THEN NULL -- Database Role
                        WHEN 'G' THEN NULL -- Windows Group
                        ELSE NULL
    [PrincipalType] = CASE dbprinc.[type]
                    WHEN 'S' THEN 'SQL User'
                    WHEN 'U' THEN 'Windows User'
                    WHEN 'R' THEN 'Database Role'
                    WHEN 'G' THEN 'Windows Group'
    [DatabaseUserName] = dbprinc.[name],
    [Role] = null,
    [PermissionType] = perm.[permission_name],
    [PermissionState] = perm.[state_desc],
    [ObjectType] = obj.[type_desc],--perm.[class_desc],
    [ObjectSchema] = OBJECT_SCHEMA_NAME(perm.major_id),
    [ObjectName] = OBJECT_NAME(perm.major_id),
    [ColumnName] = col.[name]
    --database user
    sys.database_principals dbprinc  
    --Login accounts
    sys.server_principals sprinc on dbprinc.[sid] = sprinc.[sid]
LEFT JOIN        
    sys.database_permissions perm ON perm.[grantee_principal_id] = dbprinc.[principal_id]
    --Table columns
    sys.columns col ON col.[object_id] = perm.major_id 
                    AND col.[column_id] = perm.[minor_id]
    sys.objects obj ON perm.[major_id] = obj.[object_id]
    dbprinc.[type] in ('S','U')
        WHEN @HideDatabaseDiagrams = 1 AND
        dbprinc.[name] = 'guest'
        AND (
                obj.type_desc = 'SQL_SCALAR_FUNCTION'
                AND OBJECT_NAME(perm.major_id) = 'fn_diagramobjects'
            OR (
                obj.type_desc = 'SQL_STORED_PROCEDURE'
                AND OBJECT_NAME(perm.major_id) IN
        THEN 0
        ELSE 1
    END = 1
--List all access provisioned to a sql user or windows user/group through a database or application role
    [UserName] = CASE memberprinc.[type]
                    WHEN 'S' THEN memberprinc.[name]
                    WHEN 'U' THEN sprinc.[name]
                    WHEN 'R' THEN NULL -- Database Role
                    WHEN 'G' THEN NULL -- Windows Group
                    ELSE NULL
    [UserType] = CASE memberprinc.[type]
                    WHEN 'S' THEN 'SQL User'
                    WHEN 'U' THEN 'Windows User'
                    WHEN 'R' THEN NULL -- Database Role
                    WHEN 'G' THEN NULL -- Windows Group
    [PrincipalUserName] = COALESCE(
                    CASE memberprinc.[type]
                        WHEN 'S' THEN memberprinc.[name]
                        WHEN 'U' THEN sprinc.[name]
                        WHEN 'R' THEN NULL -- Database Role
                        WHEN 'G' THEN NULL -- Windows Group
                        ELSE NULL
    [PrincipalType] = CASE memberprinc.[type]
                    WHEN 'S' THEN 'SQL User'
                    WHEN 'U' THEN 'Windows User'
                    WHEN 'R' THEN 'Database Role'
                    WHEN 'G' THEN 'Windows Group'
    [DatabaseUserName] = memberprinc.[name],
    [Role] = roleprinc.[name],
    [PermissionType] = perm.[permission_name],
    [PermissionState] = perm.[state_desc],
    [ObjectType] = obj.type_desc,--perm.[class_desc],
    [ObjectSchema] = OBJECT_SCHEMA_NAME(perm.major_id),
    [ObjectName] = OBJECT_NAME(perm.major_id),
    [ColumnName] = col.[name]
    --Role/member associations
    sys.database_role_members members
    sys.database_principals roleprinc ON roleprinc.[principal_id] = members.[role_principal_id]
    --Role members (database users)
    sys.database_principals memberprinc ON memberprinc.[principal_id] = members.[member_principal_id]
    --Login accounts
    sys.server_principals sprinc on memberprinc.[sid] = sprinc.[sid]
    sys.database_permissions perm ON perm.[grantee_principal_id] = roleprinc.[principal_id]
    --Table columns
    sys.columns col on col.[object_id] = perm.major_id 
                    AND col.[column_id] = perm.[minor_id]
    sys.objects obj ON perm.[major_id] = obj.[object_id]
        WHEN @HideDatabaseDiagrams = 1 AND
        memberprinc.[name] = 'guest'
        AND (
                obj.type_desc = 'SQL_SCALAR_FUNCTION'
                AND OBJECT_NAME(perm.major_id) = 'fn_diagramobjects'
            OR (
                obj.type_desc = 'SQL_STORED_PROCEDURE'
                AND OBJECT_NAME(perm.major_id) IN
        THEN 0
        ELSE 1
    END = 1
--List all access provisioned to the public role, which everyone gets by default
    [UserName] = '{All Users}',
    [UserType] = '{All Users}',
    [PrincipalUserName] = '{All Users}',
    [PrincipalType] = '{All Users}',
    [DatabaseUserName] = '{All Users}',
    [Role] = roleprinc.[name],
    [PermissionType] = perm.[permission_name],
    [PermissionState] = perm.[state_desc],
    [ObjectType] = obj.type_desc,--perm.[class_desc],
    [ObjectSchema] = OBJECT_SCHEMA_NAME(perm.major_id),
    [ObjectName] = OBJECT_NAME(perm.major_id),
    [ColumnName] = col.[name]
    sys.database_principals roleprinc
LEFT JOIN        
    --Role permissions
    sys.database_permissions perm ON perm.[grantee_principal_id] = roleprinc.[principal_id]
    --Table columns
    sys.columns col on col.[object_id] = perm.major_id
                    AND col.[column_id] = perm.[minor_id]
    --All objects
    sys.objects obj ON obj.[object_id] = perm.[major_id]
    --Only roles
    roleprinc.[type] = 'R' AND
    --Only public role
    roleprinc.[name] = 'public' AND
    --Only objects of ours, not the MS objects
    obj.is_ms_shipped = 0
        WHEN @HideDatabaseDiagrams = 1 AND
        roleprinc.[name] = 'public'
        AND (
                obj.type_desc = 'SQL_SCALAR_FUNCTION'
                AND OBJECT_NAME(perm.major_id) = 'fn_diagramobjects'
            OR (
                obj.type_desc = 'SQL_STORED_PROCEDURE'
                AND OBJECT_NAME(perm.major_id) IN
        THEN 0
        ELSE 1
    END = 1

Validation for 10 digit mobile number and focus input field on invalid

$().ready(function () {

            function (value, element) {
                if (value == "")
                    return false;
                return value.match(/^\d{10}$/);
            "Please enter 10 digits Contact # (No spaces or dash)"

        rules: {
            phone: "tendigits"
        messages: {
            phone: "Please enter 10 digits Contact # (No spaces or dash)",




How to solve munmap_chunk(): invalid pointer error in C++

The hint is, the output file is created even if you get this error. The automatic deconstruction of vector starts after your code executed. Elements in the vector are deconstructed as well. This is most probably where the error occurs. The way you access the vector is through vector::operator[] with an index read from stream. Try vector::at() instead of vector::operator[]. This won't solve your problem, but will show which assignment to the vector causes error.

How to check if an alert exists using WebDriver?

ExpectedConditions is obsolete, so:

        WebDriverWait wait = new WebDriverWait(driver, TimeSpan.FromSeconds(15));

C# Selenium 'ExpectedConditions is obsolete'

Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?

If you are using vitamio library and this fatal error occur.

Then make sure that in your project gradle targetSdkVersion must be less than 23.


How to list all AWS S3 objects in a bucket using Java

This is direct from AWS documentation:

AmazonS3 s3client = new AmazonS3Client(new ProfileCredentialsProvider());        

ListObjectsRequest listObjectsRequest = new ListObjectsRequest()
ObjectListing objectListing;

do {
        objectListing = s3client.listObjects(listObjectsRequest);
        for (S3ObjectSummary objectSummary : 
            objectListing.getObjectSummaries()) {
            System.out.println( " - " + objectSummary.getKey() + "  " +
                    "(size = " + objectSummary.getSize() + 
} while (objectListing.isTruncated());

How can I print a circular structure in a JSON-like format?

In Node.js, you can use util.inspect(object). It automatically replaces circular links with "[Circular]".

Albeit being built-in (no installation is required), you must import it

import * as util from 'util' // has no default export
import { inspect } from 'util' // or directly
// or 
var util = require('util')
To use it, simply call

Also be aware that you can pass options object to inspect (see link above)

inspect(myObject[, options: {showHidden, depth, colors, showProxy, ...moreOptions}])

Please, read and give kudos to commenters below...

store and retrieve a class object in shared preference

There is no way to store objects in SharedPreferences, What i did is to create a public class, put all the parameters i need and create setters and getters, i was able to access my objects,

Logging with Retrofit 2

hey guys,i already find solution:

  public static <T> T createApi(Context context, Class<T> clazz, String host, boolean debug) {
    if (singleton == null) {
        synchronized (RetrofitUtils.class) {
            if (singleton == null) {
                RestAdapter.Builder builder = new RestAdapter.Builder();
                        .setClient(new OkClient(OkHttpUtils.getInstance(context)))
                        .setConverter(new GsonConverter(GsonUtils.newInstance()))
                        .setErrorHandler(new ErrorHandlers())
                        .setLogLevel(debug ? RestAdapter.LogLevel.FULL : RestAdapter.LogLevel.NONE)/*LogLevel.BASIC will cause response.getBody().in() close*/
                        .setLog(new RestAdapter.Log() {
                            public void log(String message) {
                                if (message.startsWith("{") || message.startsWith("["))
                                else {
                singleton =;
    return singleton.create(clazz);

How to check for empty array in vba macro

Public Function IsEmptyArray(InputArray As Variant) As Boolean

   On Error GoTo ErrHandler:
   IsEmptyArray = Not (UBound(InputArray) >= 0)
   Exit Function

   IsEmptyArray = True

End Function

Check which element has been clicked with jQuery

Answer from vpiTriumph lays out the details nicely.
Here's a small handy variation for when there are unique element ids for the data set you want to access:

    var id =;
    console.log('id = ' + id); 

Everytime I run gulp anything, I get a assertion error. - Task function must be specified

Gulp 4.0 has changed the way that tasks should be defined if the task depends on another task to execute. The list parameter has been deprecated.

An example from your gulpfile.js would be:

// Starts a BrowerSync instance
gulp.task('server', ['build'], function(){
  browser.init({server: './_site', port: port});

Instead of the list parameter they have introduced gulp.series() and gulp.parallel().

This task should be changed to something like this:

// Starts a BrowerSync instance
gulp.task('server', gulp.series('build', function(){
  browser.init({server: './_site', port: port});

I'm not an expert in this. You can see a more robust example in the gulp documentation for running tasks in series or these following excellent blog posts by Jhey Thompkins and Stefan Baumgartner

How can I combine two HashMap objects containing the same types?

A small snippet I use very often to create map from other maps:

static public <K, V> Map<K, V> merge(Map<K, V>... args) {
    final Map<K, V> buffer = new HashMap<>();

    for (Map m : args) {

    return buffer;

Difference between Pragma and Cache-Control headers?

There is no difference, except that Pragma is only defined as applicable to the requests by the client, whereas Cache-Control may be used by both the requests of the clients and the replies of the servers.

So, as far as standards go, they can only be compared from the perspective of the client making a requests and the server receiving a request from the client. The defines the scenario as follows:

HTTP/1.1 caches SHOULD treat "Pragma: no-cache" as if the client had sent "Cache-Control: no-cache". No new Pragma directives will be defined in HTTP.

  Note: because the meaning of "Pragma: no-cache as a response
  header field is not actually specified, it does not provide a
  reliable replacement for "Cache-Control: no-cache" in a response

The way I would read the above:

  • if you're writing a client and need no-cache:

    • just use Pragma: no-cache in your requests, since you may not know if Cache-Control is supported by the server;
    • but in replies, to decide on whether to cache, check for Cache-Control
  • if you're writing a server:

    • in parsing requests from the clients, check for Cache-Control; if not found, check for Pragma: no-cache, and execute the Cache-Control: no-cache logic;
    • in replies, provide Cache-Control.

Of course, reality might be different from what's written or implied in the RFC!

Why does Java have an "unreachable statement" compiler error?

One of the goals of compilers is to rule out classes of errors. Some unreachable code is there by accident, it's nice that javac rules out that class of error at compile time.

For every rule that catches erroneous code, someone will want the compiler to accept it because they know what they're doing. That's the penalty of compiler checking, and getting the balance right is one of the tricker points of language design. Even with the strictest checking there's still an infinite number of programs that can be written, so things can't be that bad.

How do I call an Angular 2 pipe with multiple arguments?

In your component's template you can use multiple arguments by separating them with colons:

{{ myData | myPipe: 'arg1':'arg2':'arg3'... }}

From your code it will look like this:

new MyPipe().transform(myData, arg1, arg2, arg3)

And in your transform function inside your pipe you can use the arguments like this:

export class MyPipe implements PipeTransform { 
    // specify every argument individually   
    transform(value: any, arg1: any, arg2: any, arg3: any): any { }
    // or use a rest parameter
    transform(value: any, ...args: any[]): any { }

Beta 16 and before (2016-04-26)

Pipes take an array that contains all arguments, so you need to call them like this:

new MyPipe().transform(myData, [arg1, arg2, arg3...])

And your transform function will look like this:

export class MyPipe implements PipeTransform {    
    transform(value:any, args:any[]):any {
        var arg1 = args[0];
        var arg2 = args[1];

Spring Boot Configure and Use Two DataSources

Here you go.

Add in your file:

#first db
spring.datasource.url = [url]
spring.datasource.username = [username]
spring.datasource.password = [password]
spring.datasource.driverClassName = oracle.jdbc.OracleDriver

#second db ...
spring.secondDatasource.url = [url]
spring.secondDatasource.username = [username]
spring.secondDatasource.password = [password]
spring.secondDatasource.driverClassName = oracle.jdbc.OracleDriver

Add in any class annotated with @Configuration the following methods:

public DataSource primaryDataSource() {
    return DataSourceBuilder.create().build();

public DataSource secondaryDataSource() {
    return DataSourceBuilder.create().build();

How to change the background color of the options menu?

Thanks Marcus! It works on 2.3 smoothly by fixing some syntax errors, here's the fixed code

    protected void setMenuBackground() {
    getLayoutInflater().setFactory(new Factory() {

        public View onCreateView(final String name, final Context context,
                final AttributeSet attrs) {

            if (name.equalsIgnoreCase("")) {

                try { // Ask our inflater to create the view
                    final LayoutInflater f = getLayoutInflater();
                    final View[] view = new View[1];
                    try {
                        view[0] = f.createView(name, null, attrs);
                    } catch (InflateException e) {
                        hackAndroid23(name, attrs, f, view);
                    // Kind of apply our own background
                    new Handler().post(new Runnable() {
                        public void run() {

                    return view[0];
                } catch (InflateException e) {
                } catch (ClassNotFoundException e) {

            return null;

static void hackAndroid23(final String name,
        final android.util.AttributeSet attrs, final LayoutInflater f,
        final View[] view) {
    // mConstructorArgs[0] is only non-null during a running call to
    // inflate()
    // so we make a call to inflate() and inside that call our dully
    // XmlPullParser get's called
    // and inside that it will work to call
    // "f.createView( name, null, attrs );"!
    try {
        f.inflate(new XmlPullParser() {
            public int next() throws XmlPullParserException, IOException {
                try {
                    view[0] = (TextView) f.createView(name, null, attrs);
                } catch (InflateException e) {
                } catch (ClassNotFoundException e) {
                throw new XmlPullParserException("exit");
        }, null, false);
    } catch (InflateException e1) {
        // "exit" ignored

How do we download a blob url video

The process can differ depending on where and how the video is being hosted. Knowing that can help to answer the question in more detail.

As an example; this is how you can download videos with blob links on Vimeo.

  1. View the source code of the video player iframe
  2. Search for mp4
  3. Copy link with token query
  4. Download before token expires

Source & step-by-step instructions here.

enter image description here

How to check a string against null in java?

I'm not sure what was wrong with The MYYN's answer.

if (yourString != null) {
  //do fun stuff with yourString here

The above null check is quite alright.

If you are trying to check if a String reference is equal (ignoring case) to another string that you know is not a null reference, then do something like this:

String x = "this is not a null reference"
if (x.equalsIgnoreCase(yourStringReferenceThatMightBeNull) ) {
  //do fun stuff

If there is any doubt as to whether or not you have null references for both Strings you are comparing, you'll need to check for a null reference on at least one of them to avoid the possibility of a NullPointerException.

What precisely does 'Run as administrator' do?

Okay, let's re-iterate...

The actual question (and an excellent one at that)

"What does 'run as admin' do that being a member of the administrators group does not?"

(Answer)1. It allows you to call on administrator rights while under a user session.

Note: The question is wrongly put; one is a command and the other is a group object to apply policies.

Open a command prompt and type runas /?.

This will list all the switches the runas command line can use.

As for the Administrators Group this is based on GPEDIT or SECPOL and whether or not a Domain administrator is present or not or a network is present or not.

Usually these things will apply restrictions on computers that the administrators group is not affected by.

The question should be

What does runas admin do that run as user does not?


What does the Administrator group do that a customized user group can't?

You are mixing apples and oranges.

Windows 10 SSH keys

I found a notable exception that in Windows 10, using the described route only wrote the files to the folder if the file names where not specified in the ssh-keygen generator.

giving a custom key name caused the files containing the RSA public and private keys not to be written to the folder.

  • Open the windows command line
  • Type ssh-keygen
  • Leave file name blank, just press return,
  • Set your passphrase
  • Generate your key files. They will now exist. and be stored in c:/Users/YourUserName/.ssh/

(using Admin Command Line and Windows 10 Pro)


I have tried to install the missing packages. Installing the toolchain and restarting CLion solved all in my case:

pacman -S mingw-w64-x86_64-cmake mingw-w64-x86_64-extra-cmake-modules
pacman -S mingw-w64-x86_64-make
pacman -S mingw-w64-x86_64-gdb
pacman -S mingw-w64-x86_64-toolchain

In Tensorflow, get the names of all the Tensors in a graph

You can do

[ for n in tf.get_default_graph().as_graph_def().node]

Also, if you are prototyping in an IPython notebook, you can show the graph directly in notebook, see show_graph function in Alexander's Deep Dream notebook

IntelliJ Organize Imports

ALT+ENTER was far from eclipse habit ,in IDEA for me mouse over did not work , so in setting>IDESetting>Keymap>Show intention actions and quick-fixes I changed it to mouse left click , It did not support mouse over! but mouse left click was OK and closest to my intention.

#define in Java

Manifold Preprocessor implemented as a javac compiler plugin is designed exclusively for conditional compilation of Java source code. It uses familiar C/C++ style of directives: #define, #undef, #if, #elif, #else, #endif, #error. and #warning.

It has Maven and Gradle plugins.

The most efficient way to remove first N elements in a list?

l = [1, 2, 3, 4, 5]
del l[0:3] # Here 3 specifies the number of items to be deleted.

This is the code if you want to delete a number of items from the list. You might as well skip the zero before the colon. It does not have that importance. This might do as well.

l = [1, 2, 3, 4, 5]
del l[:3] # Here 3 specifies the number of items to be deleted.

Redirect from web api post action

    public RedirectResult Get()
        return RedirectPermanent("");

Difference between -XX:+UseParallelGC and -XX:+UseParNewGC

After a lot of searching, the best explanation I've found is from Java Performance Tuning website in Question of the month: 1.4.1 Garbage collection algorithms, January 29th, 2003

Young generation garbage collection algorithms

The (original) copying collector (Enabled by default). When this collector kicks in, all application threads are stopped, and the copying collection proceeds using one thread (which means only one CPU even if on a multi-CPU machine). This is known as a stop-the-world collection, because basically the JVM pauses everything else until the collection is completed.

The parallel copying collector (Enabled using -XX:+UseParNewGC). Like the original copying collector, this is a stop-the-world collector. However this collector parallelizes the copying collection over multiple threads, which is more efficient than the original single-thread copying collector for multi-CPU machines (though not for single-CPU machines). This algorithm potentially speeds up young generation collection by a factor equal to the number of CPUs available, when compared to the original singly-threaded copying collector.

The parallel scavenge collector (Enabled using -XX:UseParallelGC). This is like the previous parallel copying collector, but the algorithm is tuned for gigabyte heaps (over 10GB) on multi-CPU machines. This collection algorithm is designed to maximize throughput while minimizing pauses. It has an optional adaptive tuning policy which will automatically resize heap spaces. If you use this collector, you can only use the the original mark-sweep collector in the old generation (i.e. the newer old generation concurrent collector cannot work with this young generation collector).

From this information, it seems the main difference (apart from CMS cooperation) is that UseParallelGC supports ergonomics while UseParNewGC doesn't.

How to check if X server is running?

xprop -root &> /dev/null my tried & true command to test for an "X-able" situation. And, it's pretty much guaranteed to be on any system running X, of course, the command fails if not found anyways, so even if it doesnt exist, you can pretty much assume there is no X either. (thats why I use &> instead of >)

"git rebase origin" vs."git rebase origin/master"

Here's a better option:

git remote set-head -a origin

From the documentation:

With -a, the remote is queried to determine its HEAD, then $GIT_DIR/remotes//HEAD is set to the same branch. e.g., if the remote HEAD is pointed at next, "git remote set-head origin -a" will set $GIT_DIR/refs/remotes/origin/HEAD to refs/remotes/origin/next. This will only work if refs/remotes/origin/next already exists; if not it must be fetched first.

This has actually been around quite a while (since v1.6.3); not sure how I missed it!

Apply CSS style attribute dynamically in Angular JS

ngStyle directive allows you to set CSS style on an HTML element dynamically.

Expression which evals to an object whose keys are CSS style names and values are corresponding values for those CSS keys. Since some CSS style names are not valid keys for an object, they must be quoted.

ng-style="{color: myColor}"

Your code will be:

<div ng-style="{'width':'20px', 'height':'20px', 'margin-top':'10px', 'border':'solid 1px black', 'background-color':'#ff0000'}"></div>

If you want to use scope variables:

<div ng-style="{'background-color': data.backgroundCol}"></div>

Here an example on fiddle that use ngStyle, and below the code with the running snippet:

angular.module('myApp', [])_x000D_
.controller('MyCtrl', function($scope) {_x000D_
  $scope.items = [{_x000D_
      name: 'Misko',_x000D_
      title: 'Angular creator'_x000D_
    }, {_x000D_
      name: 'Igor',_x000D_
      title: 'Meetup master'_x000D_
    }, {_x000D_
      name: 'Vojta',_x000D_
      title: 'All-around superhero'_x000D_
.pending-delete {_x000D_
  background-color: pink_x000D_
<script src=""></script>_x000D_
<div ng-app="myApp" ng-controller='MyCtrl' ng-style="{color: myColor}">_x000D_
  <input type="text" ng-model="myColor" placeholder="enter a color name">_x000D_
  <div ng-repeat="item in items" ng-class="{'pending-delete': item.checked}">_x000D_
    name: {{}}, {{item.title}}_x000D_
    <input type="checkbox" ng-model="item.checked" />_x000D_
    <span ng-show="item.checked"/><span>(will be deleted)</span>_x000D_
    <div ng-hide="myColor== 'red'">I will hide if the color is set to 'red'.</div>_x000D_

Add Insecure Registry to Docker

Anyone looking to add insecure registry on amazon linux 2: You will have to change the setting under /etc/sysconfig/docker and then restart docker daemon: here's how my /etc/sysconfig/docker looks like

# The max number of open files for the daemon itself, and all
# running containers.  The default value of 1048576 mirrors the value
# used by the systemd service unit.

# Additional startup options for the Docker daemon, for example:
# OPTIONS="--ip-forward=true --iptables=true"
# By default we limit the number of open files per container
OPTIONS="--default-ulimit nofile=1024:4096 --insecure-registry yourinsecureregistryhostname:port"

# How many seconds the sysvinit script waits for the pidfile to appear
# when starting the daemon.

How can I print variable and string on same line in Python?

Use , to separate strings and variables while printing:

print("If there was a birth every 7 seconds, there would be: ", births, "births")

, in print function separates the items by a single space:

>>> print("foo", "bar", "spam")
foo bar spam

or better use string formatting:

print("If there was a birth every 7 seconds, there would be: {} births".format(births))

String formatting is much more powerful and allows you to do some other things as well, like padding, fill, alignment, width, set precision, etc.

>>> print("{:d} {:03d} {:>20f}".format(1, 2, 1.1))
1 002             1.100000
  0's padded to 2


>>> births = 4
>>> print("If there was a birth every 7 seconds, there would be: ", births, "births")
If there was a birth every 7 seconds, there would be:  4 births

# formatting
>>> print("If there was a birth every 7 seconds, there would be: {} births".format(births))
If there was a birth every 7 seconds, there would be: 4 births

Select entries between dates in doctrine 2

I believe the correct way of doing it would be to use query builder expressions:

$now = new DateTimeImmutable();
$thirtyDaysAgo = $now->sub(new \DateInterval("P30D"));
   ->add('where', $qb->expr()->between(
   ->setParameters(array('from' => $thirtyDaysAgo, 'to' => $now));

Edit: The advantage this method has over any of the other answers here is that it's database software independent - you should let Doctrine handle the date type as it has an abstraction layer for dealing with this sort of thing.

If you do something like adding a string variable in the form 'Y-m-d' it will break when it goes to a database platform other than MySQL, for example.

What Does 'zoom' do in CSS?

Surprised that nobody mentioned that zoom: 1; is useful for IE6-7, to solve most IE-only bugs by triggering hasLayout.

Python: Is there an equivalent of mid, right, and left from BASIC?

You can use this method also it will act like that


#Front Two(Left)

#Last Two(Right)# edited

mid = len(thadari) //2

lefthalf = thadari[:mid]
righthalf = thadari[mid:]

Hope it will help

What is the difference between a static method and a non-static method?

A static method belongs to the class and a non-static method belongs to an object of a class. I am giving one example how it creates difference between outputs.

public class DifferenceBetweenStaticAndNonStatic {

  static int count = 0;
  private int count1 = 0;

  public DifferenceBetweenStaticAndNonStatic(){
    count1 = count1+1;

  public int getCount1() {
    return count1;

  public void setCount1(int count1) {
    this.count1 = count1;

  public static int countStaticPosition() {
    count = count+1; 
    return count;
     * one can not use non static variables in static if we will
     * return count1 it will give compilation error. return count1;

public class StaticNonStaticCheck {

  public static void main(String[] args){
    for(int i=0;i<4;i++) {
      DifferenceBetweenStaticAndNonStatic p =new DifferenceBetweenStaticAndNonStatic();
      System.out.println("static count position is " +DifferenceBetweenStaticAndNonStatic.count);
        System.out.println("static count position is " +p.getCount1());
        System.out.println("static count position is " +DifferenceBetweenStaticAndNonStatic.countStaticPosition());

        System.out.println("next case: ");
        System.out.println(" ");



Now output will be:::

static count position is 0
static count position is 1
static count position is 1
next case: 

static count position is 1
static count position is 1
static count position is 2
next case: 

static count position is 2
static count position is 1
static count position is 3
next case:  

Sorting a List<int>

var values = new int[] {5,7,3};
var sortedValues = values.OrderBy(v => v).ToList();   // result 3,5,7

Enum String Name from Value

Use this:

string bob = nameof(EnumDisplayStatus.Visible);

Getting results between two dates in PostgreSQL

Looking at the dates for which it doesn't work -- those where the day is less than or equal to 12 -- I'm wondering whether it's parsing the dates as being in YYYY-DD-MM format?

Best way to remove the last character from a string built with stringbuilder

Use the following after the loop.


or simply change to

string commaSeparatedList = input.Aggregate((a, x) => a + ", " + x)

Most Useful Attributes

I always use attributes, [Serializable], [WebMethod], [DefaultValue], [Description("description here")].

but beside that there is a Global Attributes in c#.

[assembly: System.CLSCompliant(true)]
[assembly: AssemblyCulture("")]
[assembly: AssemblyDescription("")]

How to access the first property of a Javascript object?

Solution with lodash library:

_.find(example) // => {name: "foo1"}

but there is no guarantee of the object properties internal storage order because it depends on javascript VM implementation.

CSS to prevent child element from inheriting parent styles

Unfortunately, you're out of luck here.

There is inherit to copy a certain value from a parent to its children, but there is no property the other way round (which would involve another selector to decide which style to revert).

You will have to revert style changes manually:

div { color: green; }

form div { color: red; }

form div div.content { color: green; }

If you have access to the markup, you can add several classes to style precisely what you need:

form div.sub { color: red; }

form div div.content { /* remains green */ }

Edit: The CSS Working Group is up to something:

div.content {
  all: revert;

No idea, when or if ever this will be implemented by browsers.

Edit 2: As of March 2015 all modern browsers but Safari and IE/Edge have implemented it: (thanks, @Lea Verou!)

Edit 3: default was renamed to revert.

How to declare an array of strings in C++?

Declare an array of strings in C++ like this : char array_of_strings[][]

For example : char array_of_strings[200][8192];

will hold 200 strings, each string having the size 8kb or 8192 bytes.

use strcpy(line[i],tempBuffer); to put data in the array of strings.

How to check if a string is numeric?

If you are allowed to use third party libraries, suggest the following.


Deserializing a JSON file with JavaScriptSerializer()

Create a sub-class User with an id field and screen_name field, like this:

public class User
    public string id { get; set; }
    public string screen_name { get; set; }

public class Response {

    public string id { get; set; }
    public string text { get; set; }
    public string url { get; set; }
    public string width { get; set; }
    public string height { get; set; }
    public string size { get; set; }
    public string type { get; set; }
    public string timestamp { get; set; }
    public User user { get; set; }

Prevent textbox autofill with previously entered values

Autocomplete need to set off from textbox

<asp:TextBox ID="TextBox1" runat="server" autocomplete="off"></asp:TextBox>

Determine if Python is running inside virtualenv

  • Updated Nov 2019 (appended).

I routinely use several Anaconda-installed virtual environments (venv). This code snippet/examples enables you to determine whether or not you are in a venv (or your system environment), and to also require a specific venv for your script.

Add to Python script (code snippet):

# ----------------------------------------------------------------------------
# Want script to run in Python 3.5 (has required installed OpenCV, imutils, ... packages):
import os

# First, see if we are in a conda venv { py27: Python 2.7 | py35: Python 3.5 | tf: TensorFlow | thee : Theano }
except KeyError:
   print("\tPlease set the py35 { p3 | Python 3.5 } environment!\n")

# If we are in a conda venv, require the p3 venv:
if os.environ['CONDA_DEFAULT_ENV'] != "py35":
    print("\tPlease set the py35 { p3 | Python 3.5 } environment!\n")

# See also:
# Python: Determine if running inside virtualenv
# [ ... SNIP! ... ]


$ p2
  [Anaconda Python 2.7 venv (source activate py27)]

(py27) $ python
    Please set the py35 { p3 | Python 3.5 } environment!

(py27) $ p3
  [Anaconda Python 3.5 venv (source activate py35)]

(py35) $ python -n50

    current env: py35
    processing (live): found 2 faces and 4 eyes in this frame
    threaded OpenCV implementation
    num_frames: 50
    webcam -- approx. FPS: 18.59
    Found 2 faces and 4 eyes!
(py35) $

Update 1 -- use in bash scripts:

You can also use this approach in bash scripts (e.g., those that must run in a specific virtual environment). Example (added to bash script):

if [ $CONDA_DEFAULT_ENV ]        ## << note the spaces (important in BASH)!
        printf 'venv: operating in tf-env, proceed ...'
        printf 'Note: must run this script in tf-env venv'

Update 2 [Nov 2019]

Since my original post I've moved on from Anaconda venv (and Python itself has evolved viz-a-viz virtual environments).

Reexamining this issue, here is some updated Python code that you can insert to test that you are operating in a specific Python virtual environment (venv).

import os, re
    if'py37', os.environ['VIRTUAL_ENV']):
except KeyError:
    print("\n\tPlease set the Python3 venv [alias: p3]!\n")

Here is some explanatory code.

[victoria@victoria ~]$ date; python --version
  Thu 14 Nov 2019 11:27:02 AM PST
  Python 3.8.0

[victoria@victoria ~]$ python
  Python 3.8.0 (default, Oct 23 2019, 18:51:26) 
  [GCC 9.2.0] on linux
  Type "help", "copyright", "credits" or "license" for more information.

>>> import os, re

>>>'py37', os.environ['VIRTUAL_ENV'])
<re.Match object; span=(20, 24), match='py37'>

>>> try:
...     if'py37', os.environ['VIRTUAL_ENV']):
...       print('\n\tOperating in Python3 venv, please proceed!  :-)')
... except KeyError:
...     print("\n\tPlease set the Python3 venv [alias: p3]!\n")

    Please set the Python3 venv [alias: p3]!

>>> [Ctrl-d]
  now exiting EditableBufferInteractiveConsole...

[victoria@victoria ~]$ p3
  [Python 3.7 venv (source activate py37)]

(py37) [victoria@victoria ~]$ python --version
  Python 3.8.0

(py37) [victoria@victoria ~]$ env | grep -i virtual

(py37) [victoria@victoria ~]$ python
  Python 3.8.0 (default, Oct 23 2019, 18:51:26) 
  [GCC 9.2.0] on linux
  Type "help", "copyright", "credits" or "license" for more information.

>>> import os, re
>>> try:
...     if'py37', os.environ['VIRTUAL_ENV']):
...       print('\n\tOperating in Python3 venv, please proceed!  :-)')
... except KeyError:
...     print("\n\tPlease set the Python3 venv [alias: p3]!\n")

    Operating in Python3 venv, please proceed!  :-)

How do I tell if a regular file does not exist in Bash?

To test file existence, the parameter can be any one of the following:

-e: Returns true if file exists (regular file, directory, or symlink)
-f: Returns true if file exists and is a regular file
-d: Returns true if file exists and is a directory
-h: Returns true if file exists and is a symlink

All the tests below apply to regular files, directories, and symlinks:

-r: Returns true if file exists and is readable
-w: Returns true if file exists and is writable
-x: Returns true if file exists and is executable
-s: Returns true if file exists and has a size > 0

Example script:


if [ -f "$FILE" ]; then
   echo "File $FILE exists"
   echo "File $FILE does not exist"

What's the best way to iterate an Android Cursor?

The cursor is the Interface that represents a 2-dimensional table of any database.

When you try to retrieve some data using SELECT statement, then the database will 1st create a CURSOR object and return its reference to you.

The pointer of this returned reference is pointing to the 0th location which is otherwise called as before the first location of the Cursor, so when you want to retrieve data from the cursor, you have to 1st move to the 1st record so we have to use moveToFirst

When you invoke moveToFirst() method on the Cursor, it takes the cursor pointer to the 1st location. Now you can access the data present in the 1st record

The best way to look :

Cursor cursor

for (cursor.moveToFirst(); 
     cursor.moveToNext()) {

"date(): It is not safe to rely on the system's timezone settings..."

If you using Plesk, try it, First, Open PHP Settings, at the bottom of page, change date.timezone from DEFAULT to UTC.

enter image description here

enter image description here

Chart.js canvas resize

In IOS and Android the browser hides the toolbar when you are scrolling, thereby changing the size of the window which inturn lead chartjs to resize the graph. The solution is to maintain the aspect ratio.

var options = { 
    responsive: true,
    maintainAspectRatio: true

This should solve your problem.

Android transparent status bar and actionbar

It supports after KITKAT. Just add following code inside onCreate method of your Activity. No need any modifications to Manifest file.

                Window w = getWindow(); // in Activity's onCreate() for instance
                w.setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS, WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

Generate full SQL script from EF 5 Code First Migrations

To add to Matt wilson's answer I had a bunch of code-first entity classes but no database as I hadn't taken a backup. So I did the following on my Entity Framework project:

Open Package Manager console in Visual Studio and type the following:



Give your migration a name such as 'Initial' and then create the migration. Finally type the following:


Update-Database -Script -SourceMigration:0

The final command will create your database tables from your entity classes (provided your entity classes are well formed).

Given two directory trees, how can I find out which files differ by content?

You said Linux, so you luck out (at least it should be available, not sure when it was added):

diff --brief --recursive dir1/ dir2/ # GNU long options
diff -qr dir1/ dir2/ # common short options

Should do what you need.

If you also want to see differences for files that may not exist in either directory:

diff --brief --recursive --new-file dir1/ dir2/ # GNU long options
diff -qrN dir1/ dir2/ # common short options

Search for exact match of string in excel row using VBA Macro

Try this:

Sub GetColumns()

Dim lnRow As Long, lnCol As Long

lnRow = 3 'For testing

lnCol = Sheet1.Cells(lnRow, 1).EntireRow.Find(What:="sds", LookIn:=xlValues, LookAt:=xlPart, SearchOrder:=xlByColumns, SearchDirection:=xlNext, MatchCase:=False).Column

End Sub

Probably best not to use colIndex and rowIndex as variable names as they are already mentioned in the Excel Object Library.

#1055 - Expression of SELECT list is not in GROUP BY clause and contains nonaggregated column this is incompatible with sql_mode=only_full_group_by

You can disable sql_mode=only_full_group_by by some command you can try this by terminal or MySql IDE



I have tried this and worked for me. Thanks :)


The group_concat supports its own order by clause

So you should be able to write:

SELECT li.clientid, group_concat(li.views order by views) AS views,
group_concat(li.percentage order by percentage) 
FROM table_views GROUP BY client_id

CSS selector for first element with class

You can change your code to something like this to get it work

<div class="home">
  <p class="red">first</p>
  <p class="red">second</p>
  <p class="red">third</p>
  <p class="red">fourth</p>

This does the job for you

.home span + .red{
      border:3px solid green;

Here is a CSS reference from SnoopCode about that.

Set select option 'selected', by value

  • You must take it in mind the value you want to change dynamically, must be same as one present in the options you define in your HTML as it is case sensative. You can change your select box dynamically as follows,

$("div#YOUR_ID").val(VALUE_CHANGED).change(); //value must present in options you selected otherwise it will not work

Possible reason for NGINX 499 error codes

I know this is an old thread, but it exactly matches what recently happened to me and I thought I'd document it here. The setup (in Docker) is as follows:

  • nginx_proxy
  • nginx
  • php_fpm running the actual app.

The symptom was a "502 Gateway Timeout" on the application login prompt. Examination of logs found:

  • the button works via an HTTP POST to /login ... and so ...
  • nginx-proxy got the /login request, and eventually reported a timeout.
  • nginx returned a 499 response, which of course means "the host died."
  • the /login request did not appear at all(!) in the FPM server's logs!
  • there were no tracebacks or error-messages in FPM ... nada, zero, zippo, none.

It turned out that the problem was a failure to connect to the database to verify the login. But how to figure that out turned out to be pure guesswork.

The complete absence of application traceback logs ... or even a record that the request had been received by FPM ... was a complete (and, devastating ...) surprise to me. Yes, the application is supposed to log failures, but in this case it looks like the FPM worker process died with a runtime error, leading to the 499 response from nginx. Now, this obviously is a problem in our application ... somewhere. But I wanted to record the particulars of what happened for the benefit of the next folks who face something like this.

Should I use typescript? or I can just use ES6?

I've been using Typescript in my current angular project for about a year and a half and while there are a few issues with definitions every now and then the DefinitelyTyped project does an amazing job at keeping up with the latest versions of most popular libraries.

Having said that there is a definite learning curve when transitioning from vanilla JavaScript to TS and you should take into account the ability of you and your team to make that transition. Also if you are going to be using angular 1.x most of the examples you will find online will require you to translate them from JS to TS and overall there are not a lot of resources on using TS and angular 1.x together right now.

If you plan on using angular 2 there are a lot of examples using TS and I think the team will continue to provide most of the documentation in TS, but you certainly don't have to use TS to use angular 2.

ES6 does have some nice features and I personally plan on getting more familiar with it but I would not consider it a production-ready language at this point. Mainly due to a lack of support by current browsers. Of course, you can write your code in ES6 and use a transpiler to get it to ES5, which seems to be the popular thing to do right now.

Overall I think the answer would come down to what you and your team are comfortable learning. I personally think both TS and ES6 will have good support and long futures, I prefer TS though because you tend to get language features quicker and right now the tooling support (in my opinion) is a little better.

How can I increase the JVM memory?

When starting the JVM, two parameters can be adjusted to suit your memory needs :


specifies the initial Java heap size and


the maximum Java heap size.

"Server Tomcat v7.0 Server at localhost failed to start" without stack trace while it works in terminal

In my case, the problem was in the web.xml file, where i forgot to precede the url-pattern with a "/" (e.g. /

What solved my problem was, as mentioned above by @Ajak6, by adding the servlet API as an external JAR library for the project.

However, I found a better way, by adding Tomcat to the target runtime as follow;

1) project > properties

2) on the side menu select "Targeted runtimes"

3) select Tomcat (click apply)

4) click ok

Cursor adapter and sqlite example

In Android, How to use a Cursor with a raw query in sqlite:

Cursor c = sampleDB.rawQuery("SELECT FirstName, Age FROM mytable " +
           "where Age > 10 LIMIT 5", null);

if (c != null ) {
    if  (c.moveToFirst()) {
        do {
            String firstName = c.getString(c.getColumnIndex("FirstName"));
            int age = c.getInt(c.getColumnIndex("Age"));
            results.add("" + firstName + ",Age: " + age);
        }while (c.moveToNext());

Add an index (numeric ID) column to large data frame

If your data.frame is a data.table, you can use special symbol .I:

data[, ID := .I]

ARM compilation error, VFP registers used by executable, not object file

In my case CFLAGS = -O0 -g -Wall -I. -mcpu=cortex-m4 -mthumb -mfpu=fpv4-sp-d16 -mfloat-abi=soft has helped. As you can see, i used it for my stm32f407.

How do I access refs of a child component in the parent component

Recommended for React versions prior to 16.3

If it cannot be avoided the suggested pattern extracted from the React docs would be:

import React, { Component } from 'react';

const Child = ({ setRef }) => <input type="text" ref={setRef} />;

class Parent extends Component {
    constructor(props) {
        this.setRef = this.setRef.bind(this);

    componentDidMount() {
        // Calling a function on the Child DOM element

    setRef(input) {
        this.childRef = input;

    render() {
        return <Child setRef={this.setRef} />

The Parent forwards a function as prop bound to Parent's this. When React calls the Child's ref prop setRef it will assign the Child's ref to the Parent's childRef property.

Recommended for React >= 16.3

Ref forwarding is an opt-in feature that lets some components take a ref they receive, and pass it further down (in other words, “forward” it) to a child.

We create Components that forward their ref with React.forwardRef. The returned Component ref prop must be of the same type as the return type of React.createRef. Whenever React mounts the DOM node then property current of the ref created with React.createRef will point to the underlying DOM node.

import React from "react";

const LibraryButton = React.forwardRef((props, ref) => (
  <button ref={ref} {...props}>

class AutoFocus extends React.Component {
  constructor(props) {
    this.childRef = React.createRef();
    this.onClick = this.onClick.bind(this);

  componentDidMount() {

  onClick() {

  render() {
    return <LibraryButton onClick={this.onClick} ref={this.childRef} />;

Forwarding refs HOC example

Created Components are forwarding their ref to a child node.

function logProps(Component) {
  class LogProps extends React.Component {
    componentDidUpdate(prevProps) {
      console.log('old props:', prevProps);
      console.log('new props:', this.props);

    render() {
      const {forwardedRef,} = this.props;

      // Assign the custom prop "forwardedRef" as a ref
      return <Component ref={forwardedRef} {} />;

  // Note the second param "ref" provided by React.forwardRef.
  // We can pass it along to LogProps as a regular prop, e.g. "forwardedRef"
  // And it can then be attached to the Component.
  return React.forwardRef((props, ref) => {
    return <LogProps {...props} forwardedRef={ref} />;

See Forwarding Refs in React docs.

Converting string to integer

The function you need is CInt.

ie CInt(PrinterLabel)

See Type Conversion Functions (Visual Basic) on MSDN

Edit: Be aware that CInt and its relatives behave differently in and VBScript. For example, in, CInt casts to a 32-bit integer, but in VBScript, CInt casts to a 16-bit integer. Be on the lookout for potential overflows!

Is it safe to clean docker/overlay2/


/# df
/dev/xvda1      51467016 39384516   9886300  80% /

Ok, let's first try system prune

#/ docker system prune --volumes
/# df
/dev/xvda1      51467016 38613596  10657220  79% /

Not so great, seems like it cleaned up a few megabytes. Let's go crazy now:

/# sudo su
/# service docker stop
/# cd /var/lib/docker
/var/lib/docker# rm -rf *
/# service docker start
/var/lib/docker# df
/dev/xvda1      51467016 8086924  41183892  17% /

Nice! Just remember that this is NOT recommended in anything but a throw-away server. At this point Docker's internal database won't be able to find any of these overlays and it may cause unintended consequences.

How to vertically align a html radio button to it's label?

Adding display:inline-block to the labels and giving them padding-top would fix this, I think. Also, just setting the line-height on the labels would also.

How can I add a box-shadow on one side of an element?

To get the clipped effect on up to two sides you can use pseudo elements with background gradients.

header::before, main::before, footer::before, header::after, main::after, footer::after {
    display:    block;
    content:    '';
    position:   absolute;
    width:      8px;
    height:     100%;
    top:        0px;

header::before, main::before, footer::before {
    left:       -8px;
    background: linear-gradient(to left, rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0));

header::after, main::after, footer::after {
    right:      -8px;
    background: linear-gradient(to right, rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0));

will add a nice shadow-like effect to the left and right of the elements that normally make up a document.

Display string as html in mvc view

I had a similar problem recently, and google landed me here, so I put this answer here in case others land here as well, for completeness.

I noticed that when I had badly formatted html, I was actually having all my html tags stripped out, with just the non-tag content remaining. I particularly had a table with a missing opening table tag, and then all my html tags from the entire string where ripped out completely.

So, if the above doesn't work, and you're still scratching your head, then also check you html for being valid.

I notice even after I got it working, MVC was adding tbody tags where I had none. This tells me there is clean up happening (MVC 5), and that when it can't happen, it strips out all/some tags.

Error: Node Sass does not yet support your current environment: Windows 64-bit with false

I got this error, with angular 7, what helped me is, From the windows power shell I run the command:

npm install --global --production windows-build-tools

then again I reopen my VS Code, on it's terminal I run the same command npm uninstall node-sass and npm install node-sass

How to test if a DataSet is empty?

Don't forget to set table name da.Fill(ds,"tablename");

So you return data using table name instead of 0

if (ds.Tables["tablename"].Rows.Count == 0)
  MessageBox.Show("No result found");

SQL Server: converting UniqueIdentifier to string in a case statement

In my opinion, uniqueidentifier / GUID is neither a varchar nor an nvarchar but a char(36). Therefore I use:

CAST(xyz AS char(36))

Zooming MKMapView to fit annotation pins?

In Swift use

mapView.showAnnotations(annotationArray, animated: true)

In Objective c

[mapView showAnnotations:annotationArray animated:YES];

How do I create a slug in Django?

There is corner case with some utf-8 characters


>>> from django.template.defaultfilters import slugify
>>> slugify(u"test aescóln")
u'test-aescon' # there is no "l"

This can be solved with Unidecode

>>> from unidecode import unidecode
>>> from django.template.defaultfilters import slugify
>>> slugify(unidecode(u"test aescóln"))

Why maven? What are the benefits?

Maven is one of the tools where you need to actually decide up front that you like it and want to use it, since you will spend quite some time learning it, and having made said decision once and for all will allow you to skip all kinds of doubt while learning (because you like it and want to use it)!

The strong conventions help in many places - like Hudson that can do wonders with Maven projects - but it may be hard to see initially.

edit: As of 2016 Maven is the only Java build tool where all three major IDEs can use the sources out of the box. In other words, using maven makes your build IDE-agnostic. This allows for e.g. using Netbeans profiling even if you normally work In eclipse

Java 8 LocalDate Jackson format

@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
@JsonSerialize(using = LocalDateTimeSerializer.class)
@JsonDeserialize(using = LocalDateTimeDeserializer.class)
private LocalDateTime createdDate;

Better way to find index of item in ArrayList?

If your List is sorted and has good random access (as ArrayList does), you should look into Collections.binarySearch. Otherwise, you should use List.indexOf, as others have pointed out.

But your algorithm is sound, fwiw (other than the == others have pointed out).

When is the init() function run?

init will be called everywhere uses its package(no matter blank import or import), but only one time.

this is a package:

package demo

import (

var count int

func init() {

// Do do
func Do() {

any package(main package or any test package) import it as blank :

_ ""

or import it using it func:


func someFunc(){

the init will log 0 only one time. the first package using it, its init func will run before the package's init. So:

A calls B, B calls C, all of them have init func, the C's init will be run first before B's, B's before A's.

How to call shell commands from Ruby

This is not really an answer but maybe someone will find it useful:

When using TK GUI on Windows, and you need to call shell commands from rubyw, you will always have an annoying CMD window popping up for less then a second.

To avoid this you can use:'Shell.Application').ShellExecute('ipconfig > log.txt','','','open',0)

or'WScript.Shell').Run('ipconfig > log.txt',0,0)

Both will store the ipconfig output inside log.txt, but no windows will come up.

You will need to require 'win32ole' inside your script.

system(), exec() and spawn() will all pop up that annoying window when using TK and rubyw.

encrypt and decrypt md5

It's not possible to decrypt MD5 hash which created. You need all information to decrypt the MD5 value which was used during encryption.

You can use AES algorithm to encrypt and decrypt

JavaScript AES encryption and decryption (Advanced Encryption Standard)

Error: unmappable character for encoding UTF8 during maven compilation

When i inspect the console i found that the version of maven compiler is 2.5.1 but in other side i try to build my project with maven 3.2.2.So after writting the exact version in pom.xml, it works good. Here is the full tag:


Automatically start a Windows Service on install

Programmatic options for controlling services:

  • Native code can used, "Starting a Service". Maximum control with minimum dependencies but the most work.
  • WMI: Win32_Service has a StartService method. This is good for cases where you need to be able to perform other processing (e.g. to select which service).
  • PowerShell: execute Start-Service via RunspaceInvoke or by creating your own Runspace and using its CreatePipeline method to execute. This is good for cases where you need to be able to perform other processing (e.g. to select which service) with a much easier coding model than WMI, but depends on PSH being installed.
  • A .NET application can use ServiceController

SQL Not Like Statement not working

Is the value of your particular COMMENT column null?

Sometimes NOT LIKE doesn't know how to behave properly around nulls.

Escape double quote character in XML

You can try using the a backslash followed by a "u" and then the unicode value for the character, for example the unicode value of the double quote is

" -> U+0022

Therefore if you were setting it as part of text in XML in android it would look something like this,

     android:text=" \u0022 Showing double quotes \u0022 "/>

This would produce a text in the TextView roughly something like this

" Showing double quotes "

You can find unicode of most symbols and characters here

Match exact string

Use the start and end delimiters: ^abc$

How to add a new project to Github using VS Code

Go to VS COde -> View -> Terminal

enter image description here

git init git add . git commit -m "FirstCommit" git remote add origin git pull origin master git push -f origin master

Note : Some time git push -u origin master doesn't work anticipated.

Why isn't Python very good for functional programming?

Another reason not mentioned above is that many built-in functions and methods of built-in types modify an object but do not return the modified object. If those modified objects were returned, that would make functional code cleaner and more concise. For example, if some_list.append(some_object) returned some_list with some_object appended.

Short IF - ELSE statement

As others have indicated, something of the form

x ? y : z

is an expression, not a (complete) statement. It is an rvalue which needs to get used someplace - like on the right side of an assignment, or a parameter to a function etc.

Perhaps you could look at this:

How do I open a new window using jQuery?

This works:

myWindow ='','myWindow', "width=200, height=200");

How to get different colored lines for different plots in a single figure?

Matplotlib does this by default.


import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)

Basic plot demonstrating color cycling

And, as you may already know, you can easily add a legend:

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)

plt.legend(['y = x', 'y = 2x', 'y = 3x', 'y = 4x'], loc='upper left')

Basic plot with legend

If you want to control the colors that will be cycled through:

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

plt.gca().set_color_cycle(['red', 'green', 'blue', 'yellow'])

plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)

plt.legend(['y = x', 'y = 2x', 'y = 3x', 'y = 4x'], loc='upper left')

Plot showing control over default color cycling

If you're unfamiliar with matplotlib, the tutorial is a good place to start.


First off, if you have a lot (>5) of things you want to plot on one figure, either:

  1. Put them on different plots (consider using a few subplots on one figure), or
  2. Use something other than color (i.e. marker styles or line thickness) to distinguish between them.

Otherwise, you're going to wind up with a very messy plot! Be nice to who ever is going to read whatever you're doing and don't try to cram 15 different things onto one figure!!

Beyond that, many people are colorblind to varying degrees, and distinguishing between numerous subtly different colors is difficult for more people than you may realize.

That having been said, if you really want to put 20 lines on one axis with 20 relatively distinct colors, here's one way to do it:

import matplotlib.pyplot as plt
import numpy as np

num_plots = 20

# Have a look at the colormaps here and decide which one you'd like:
colormap =
plt.gca().set_prop_cycle(plt.cycler('color',, 1, num_plots))))

# Plot several different functions...
x = np.arange(10)
labels = []
for i in range(1, num_plots + 1):
    plt.plot(x, i * x + 5 * i)
    labels.append(r'$y = %ix + %i$' % (i, 5*i))

# I'm basically just demonstrating several different legend options here...
plt.legend(labels, ncol=4, loc='upper center', 
           bbox_to_anchor=[0.5, 1.1], 
           columnspacing=1.0, labelspacing=0.0,
           handletextpad=0.0, handlelength=1.5,
           fancybox=True, shadow=True)

Unique colors for 20 lines based on a given colormap

Android get current Locale, not default

I´ve used this:

String currentLanguage = Locale.getDefault().getDisplayLanguage();
if (currentLanguage.toLowerCase().contains("en")) {
   //do something

Find oldest/youngest datetime object in a list

The datetime module has its own versions of min and max as available methods.

null vs empty string in Oracle

In oracle an empty varchar2 and null are treated the same, and your observations show that.

when you write:

select * from table where a = '';

its the same as writing

select * from table where a = null;

and not a is null

which will never equate to true, so never return a row. same on the insert, a NOT NULL means you cant insert a null or an empty string (which is treated as a null)

Send email by using codeigniter library via localhost

Please check my working code.

function sendMail()
    $config = Array(
  'protocol' => 'smtp',
  'smtp_host' => 'ssl://',
  'smtp_port' => 465,
  'smtp_user' => '[email protected]', // change it to yours
  'smtp_pass' => 'xxx', // change it to yours
  'mailtype' => 'html',
  'charset' => 'iso-8859-1',
  'wordwrap' => TRUE

        $message = '';
        $this->load->library('email', $config);
      $this->email->from('[email protected]'); // change it to yours
      $this->email->to('[email protected]');// change it to yours
      $this->email->subject('Resume from JobsBuddy for your Job posting');
      echo 'Email sent.';


Convert String to double in Java

Citing the quote from Robertiano above again - because this is by far the most versatile and localization adaptive version. It deserves a full post!

Another option:

DecimalFormat df = new DecimalFormat(); 
DecimalFormatSymbols sfs = new DecimalFormatSymbols();
double d = df.parse(number).doubleValue();

Unable to execute dex: method ID not in [0, 0xffff]: 65536

The perfect solution for this would be to work with Proguard. as aleb mentioned in the comment. It will decrease the size of the dex file by half.

AngularJS dynamic routing

Ok solved it.

Added the solution to GitHub -

In my app.js routing config:

$routeProvider.when('/pages/:name', {
    templateUrl: '/pages/home.html', 
    controller: CMSController 

Then in my CMS controller:

function CMSController($scope, $route, $routeParams) {

    $route.current.templateUrl = '/pages/' + $ + ".html";

    $.get($route.current.templateUrl, function (data) {
        $scope.$apply(function () {
CMSController.$inject = ['$scope', '$route', '$routeParams'];

With #views being my <div id="views" ng-view></div>

So now it works with standard routing and dynamic routing.

To test it I copied about.html called it portfolio.html, changed some of it's contents and entered /#/pages/portfolio into my browser and hey presto portfolio.html was displayed....

Updated Added $apply and $compile to the html so that dynamic content can be injected.

What is the behavior difference between return-path, reply-to and from?

Another way to think about Return-Path vs Reply-To is to compare it to snail mail.

When you send an envelope in the mail, you specify a return address. If the recipient does not exist or refuses your mail, the postmaster returns the envelope back to the return address. For email, the return address is the Return-Path.

Inside of the envelope might be a letter and inside of the letter it may direct the recipient to "Send correspondence to example address". For email, the example address is the Reply-To.

In essence, a Postage Return Address is comparable to SMTP's Return-Path header and SMTP's Reply-To header is similar to the replying instructions contained in a letter.

How do I use valgrind to find memory leaks?

Try this:

valgrind --leak-check=full -v ./your_program

As long as valgrind is installed it will go through your program and tell you what's wrong. It can give you pointers and approximate places where your leaks may be found. If you're segfault'ing, try running it through gdb.

Generating a Random Number between 1 and 10 Java

This will work for generating a number 1 - 10. Make sure you import Random at the top of your code.

import java.util.Random;

If you want to test it out try something like this.

Random rn = new Random();

for(int i =0; i < 100; i++)
    int answer = rn.nextInt(10) + 1;

Also if you change the number in parenthesis it will create a random number from 0 to that number -1 (unless you add one of course like you have then it will be from 1 to the number you've entered).

How to set session variable in jquery?

Use localStorage to store the fact that you opened the page :

$(document).ready(function() {
    var yetVisited = localStorage['visited'];
    if (!yetVisited) {
        // open popup
        localStorage['visited'] = "yes";

Rails: How can I set default values in ActiveRecord?

I strongly suggest using the "default_value_for" gem:

There are some tricky scenarios that pretty much require overriding the initialize method, which that gem does.


Your db default is NULL, your model/ruby-defined default is "some string", but you actually want to set the value to nil for whatever reason: nil)

Most solutions here will fail to set the value to nil, and will instead set it to the default.

OK, so instead of taking the ||= approach, you switch to my_attr_changed?...

BUT now imagine your db default is "some string", your model/ruby-defined default is "some other string", but under a certain scenario, you want to set the value to "some string" (the db default): 'some_string')

This will result in my_attr_changed? being false because the value matches the db default, which in turn will fire your ruby-defined default code and set the value to "some other string" -- again, not what you desired.

For those reasons I don't think this can properly be accomplished with just an after_initialize hook.

Again, I think the "default_value_for" gem is taking the right approach:

Oracle 10g: Extract data (select) from XML (CLOB Type)

Try this instead:

select xmltype(t.xml).extract('//fax/text()').getStringVal() from mytab t

How to get position of a certain element in strings vector, to use it as an index in ints vector?

To get a position of an element in a vector knowing an iterator pointing to the element, simply subtract v.begin() from the iterator:

ptrdiff_t pos = find(Names.begin(), Names.end(), old_name_) - Names.begin();

Now you need to check pos against Names.size() to see if it is out of bounds or not:

if(pos >= Names.size()) {
    //old_name_ not found

vector iterators behave in ways similar to array pointers; most of what you know about pointer arithmetic can be applied to vector iterators as well.

Starting with C++11 you can use std::distance in place of subtraction for both iterators and pointers:

ptrdiff_t pos = distance(Names.begin(), find(Names.begin(), Names.end(), old_name_));

How to link to part of the same document in Markdown?

The pandoc manual explains how to link to your headers, using their identifier. I did not check support of this by other parsers, but it was reported that it does not work on github.

The identifier can be specified manually:

## my heading text {#mht}

Some normal text here,
including a [link to the header](#mht).

or you can use the auto-generated identifier (in this case #my-heading-text). Both are explained in detail in the pandoc manual.

NOTE: This only works when converting to HTML, LaTex, ConTeXt, Textile or AsciiDoc.

What operator is <> in VBA

in sql... we use it for "not equals"... I am guessing, its the same in VB aswell.

Styling input buttons for iPad and iPhone

Please add this css code

input {
-webkit-appearance: none;
-moz-appearance: none;
appearance: none;

Export HTML page to PDF on user click using JavaScript

This is because you define your "doc" variable outside of your click event. The first time you click the button the doc variable contains a new jsPDF object. But when you click for a second time, this variable can't be used in the same way anymore. As it is already defined and used the previous time.

change it to:

$(function () {

    var specialElementHandlers = {
        '#editor': function (element,renderer) {
            return true;
 $('#cmd').click(function () {
        var doc = new jsPDF();
            $('#target').html(), 15, 15, 
            { 'width': 170, 'elementHandlers': specialElementHandlers }, 
            function(){'sample-file.pdf'); }


and it will work.

issue ORA-00001: unique constraint violated coming in INSERT/UPDATE

Oracle's error message should be somewhat longer. It usually looks like this:

ORA-00001: unique constraint (TABLE_UK1) violated

The name in parentheses is the constrait name. It tells you which constraint was violated.

Initializing a struct to 0

See §6.7.9 Initialization:

21 If there are fewer initializers in a brace-enclosed list than there are elements or members of an aggregate, or fewer characters in a string literal used to initialize an array of known size than there are elements in the array, the remainder of the aggregate shall be initialized implicitly the same as objects that have static storage duration.

So, yes both of them work. Note that in C99 a new way of initialization, called designated initialization can be used too:

myStruct _m1 = {.c2 = 0, .c1 = 1};

Rerouting stdin and stdout from C

And in the meantime, there's a C source code library that will do all this for you, redirecting stdout or stderr. But the cool part is that it lets you assign as many callback functions as you want to the intercepted streams, allowing you then to very easily send a single message to multiple destinations, a DB, a text file, etc.

On top of that, it makes it trivial to create new streams that look and behave the same as stdout and stderr, where you can redirect these new streams to multiple locations as well.

look for U-Streams C library on *oogle.

How to change port for jenkins window service when 8080 is being used

On Windows (with Windows Service).

Edit the file C:\Program Files (x86)\Jenkins\jenkins.xml with 8083 if you want 8083 port.

<arguments>-Xrs -Xmx256m -Dhudson.lifecycle=hudson.lifecycle.WindowsServiceLifecycle -jar "%BASE%\jenkins.war" --httpPort=8083</arguments>

git pull aborted with error filename too long

Open your.gitconfig file to add the longpaths property. So it will look like the following:

symlinks = false
autocrlf = true
longpaths = true

Is there a performance difference between i++ and ++i in C?

Please don't let the question of "which one is faster" be the deciding factor of which to use. Chances are you're never going to care that much, and besides, programmer reading time is far more expensive than machine time.

Use whichever makes most sense to the human reading the code.

Select distinct rows from datatable in Linq

We can get the distinct similar to the example shown below

           var  distinctValues =  DetailedBreakDown_Table.AsEnumerable().Select(r => new
                InvestmentVehicleID = r.Field<string>("InvestmentVehicleID"),
                Universe = r.Field<string>("Universe"),
                AsOfDate = _imqDate,
                Ticker = "",
                Cusip = "",
                PortfolioDate = r.Field<DateTime>("PortfolioDate")

            } ).Distinct();

WPF Label Foreground Color

The title "WPF Label Foreground Color" is very simple (exactly what I was looking for) but the OP's code is so cluttered it's easy to miss how simple it can be to set text foreground color on two different labels:

    <Label Foreground="Red">Red text</Label>
    <Label Foreground="Blue">Blue text</Label>

In summary, No, there was nothing wrong with your snippet.

What does 'wb' mean in this code, using Python?

That is the mode with which you are opening the file. "wb" means that you are writing to the file (w), and that you are writing in binary mode (b).

Check out the documentation for more: clicky

Uncaught SoapFault exception: [HTTP] Error Fetching http headers

Please update your php.ini with

default_socket_timeout = 120

You can create your own php.ini if php is installed a CGI instead of a Apache module

How to escape special characters in building a JSON string?

regarding AlexB's post:

 \'  Apostrophe or single quote
 \"  Double quote

escaping single quotes is only valid in single quoted json strings
escaping double quotes is only valid in double quoted json strings


'Bart\'s car'       -> valid
'Bart says \"Hi\"'  -> invalid

How can I read and parse CSV files in C++?

Here is code for reading a matrix, note you also have a csvwrite function in matlab

void loadFromCSV( const std::string& filename )
    std::ifstream       file( filename.c_str() );
    std::vector< std::vector<std::string> >   matrix;
    std::vector<std::string>   row;
    std::string                line;
    std::string                cell;

    while( file )
        std::stringstream lineStream(line);

        while( std::getline( lineStream, cell, ',' ) )
            row.push_back( cell );

        if( !row.empty() )
            matrix.push_back( row );

    for( int i=0; i<int(matrix.size()); i++ )
        for( int j=0; j<int(matrix[i].size()); j++ )
            std::cout << matrix[i][j] << " ";

        std::cout << std::endl;

Git Pull While Ignoring Local Changes?

The command bellow wont work always. If you do just:

$ git checkout thebranch
Already on 'thebranch'
Your branch and 'origin/thebranch' have diverged,
and have 23 and 7 different commits each, respectively.

$ git reset --hard
HEAD is now at b05f611 Here the commit message bla, bla

$ git pull
Auto-merging thefile1.c
CONFLICT (content): Merge conflict in thefile1.c
CONFLICT (content): Merge conflict in
Automatic merge failed; fix conflicts and then commit the result.

and so on...

To really start over, downloading thebranch and overwriting all your local changes, just do:

$ git checkout thebranch
$ git reset --hard origin/thebranch

This will work just fine.

$ git checkout thebranch
Already on 'thebranch'
Your branch and 'origin/thebranch' have diverged,
and have 23 and 7 different commits each, respectively.

$ git reset --hard origin/thebranch
HEAD is now at 7639058 Here commit message again...

$ git status
# On branch thebranch
nothing to commit (working directory clean)

$ git checkout thebranch
Already on 'thebranch'

Google Maps API V3 : How show the direction from a point A to point B (Blue line)?

Using Javascript

I created a working demo that shows how to use the Google Maps API Directions Service in Javascript through a

  • DirectionsService object to send and receive direction requests
  • DirectionsRenderer object to render the returned route on the map

function initMap() {_x000D_
  var pointA = new google.maps.LatLng(51.7519, -1.2578),_x000D_
    pointB = new google.maps.LatLng(50.8429, -0.1313),_x000D_
    myOptions = {_x000D_
      zoom: 7,_x000D_
      center: pointA_x000D_
    map = new google.maps.Map(document.getElementById('map-canvas'), myOptions),_x000D_
    // Instantiate a directions service._x000D_
    directionsService = new google.maps.DirectionsService,_x000D_
    directionsDisplay = new google.maps.DirectionsRenderer({_x000D_
      map: map_x000D_
    markerA = new google.maps.Marker({_x000D_
      position: pointA,_x000D_
      title: "point A",_x000D_
      label: "A",_x000D_
      map: map_x000D_
    markerB = new google.maps.Marker({_x000D_
      position: pointB,_x000D_
      title: "point B",_x000D_
      label: "B",_x000D_
      map: map_x000D_
  // get route from A to B_x000D_
  calculateAndDisplayRoute(directionsService, directionsDisplay, pointA, pointB);_x000D_
function calculateAndDisplayRoute(directionsService, directionsDisplay, pointA, pointB) {_x000D_
    origin: pointA,_x000D_
    destination: pointB,_x000D_
    travelMode: google.maps.TravelMode.DRIVING_x000D_
  }, function(response, status) {_x000D_
    if (status == google.maps.DirectionsStatus.OK) {_x000D_
    } else {_x000D_
      window.alert('Directions request failed due to ' + status);_x000D_
    body {_x000D_
      height: 100%;_x000D_
      margin: 0;_x000D_
      padding: 0;_x000D_
    #map-canvas {_x000D_
      height: 100%;_x000D_
      width: 100%;_x000D_
<script src=""></script>_x000D_
<div id="map-canvas"></div>

Also on Jsfiddle:

Using Google Maps Web Services

You can use the Web Services using an API_KEY issuing a request like this:

An API_KEY can be obtained in the Google Developer Console with a quota of 2,500 free requests/day.

A request can return JSON or XML results that can be used to draw a path on a map.

Official documentation for Web Services using the Google Maps Directions API are here

Get child node index



Explanation :

  • element.parentNode.children ? Returns the brothers of element, including that element.

  • Array.from ? Casts the constructor of children to an Array object

  • indexOf ? You can apply indexOf because you now have an Array object.

How do I delete everything below row X in VBA/Excel?

It sounds like something like the below will suit your needs:

With Sheets("Sheet1")
    .Rows( X & ":" & .Rows.Count).Delete
End With

Where X is a variable that = the row number ( 415 )

How to compare dates in Java?

Use compareTo:


Vertically align text within input field of fixed-height without display: table or padding?

After much searching and frustration a combo of setting height, line height and no padding worked for me when using a fixed height (24px) background image for a text input field.

.form-text {
    color: white;
    outline: none;
    background-image: url(input_text.png);
    border-width: 0px;
    padding: 0px 10px 0px 10px;
    margin: 0px;
    width: 274px;
    height: 24px;
    line-height: 24px;
    vertical-align: middle;

Passing an array of parameters to a stored procedure

You could use a temp table which the stored procedure expects to exist. This will work on older versions of SQL Server, which do not support XML etc.

(INT myid)
    DELETE YourTable
    FROM YourTable                    

How do I check if a given Python string is a substring of another one?

Try using in like this:

>>> x = 'hello'
>>> y = 'll'
>>> y in x

Finding square root without using sqrt function?

Why not try to use the Babylonian method for finding a square root.

Here is my code for it:

double sqrt(double number)
    double error = 0.00001; //define the precision of your result
    double s = number;

    while ((s - number / s) > error) //loop until precision satisfied 
        s = (s + number / s) / 2;
    return s;

Good luck!

click or change event on radio using jquery



instead of


or you can use a shorthand form