Programs & Examples On #Mcisendstring

What does .pack() do?

The pack() method is defined in Window class in Java and it sizes the frame so that all its contents are at or above their preferred sizes.

How do I undo a checkout in git?

Try this first:

git checkout master

(If you're on a different branch than master, use the branch name there instead.)

If that doesn't work, try...

For a single file:

git checkout HEAD /path/to/file

For the entire repository working copy:

git reset --hard HEAD

And if that doesn't work, then you can look in the reflog to find your old head SHA and reset to that:

git reflog
git reset --hard <sha from reflog>

HEAD is a name that always points to the latest commit in your current branch.

Parsing GET request parameters in a URL that contains another URL

$get_url = "";
$my_url = "http://localhost/test.php?id=" . urlencode($get_url);

$my_url outputs:


So now you can get this value using $_GET['id'] or $_REQUEST['id'] (decoded).

echo urldecode($_GET["id"]);


To get every GET parameter:

foreach ($_GET as $key=>$value) {
  echo "$key = " . urldecode($value) . "<br />\n";

$key is GET key and $value is GET value for $key.

Or you can use alternative solution to get array of GET params

$get_parameters = array();
if (isset($_SERVER['QUERY_STRING'])) {
  $pairs = explode('&', $_SERVER['QUERY_STRING']);
  foreach($pairs as $pair) {
    $part = explode('=', $pair);
    $get_parameters[$part[0]] = sizeof($part)>1 ? urldecode($part[1]) : "";

$get_parameters is same as url decoded $_GET.

Class constants in python

Expanding on betabandido's answer, you could write a function to inject the attributes as constants into the module:

def module_register_class_constants(klass, attr_prefix):
        (name, getattr(klass, name)) for name in dir(klass) if name.startswith(attr_prefix)

class Animal(object):
    SIZE_HUGE = "Huge"
    SIZE_BIG = "Big"

module_register_class_constants(Animal, "SIZE_")

class Horse(Animal):
    def printSize(self):
        print SIZE_BIG

Illegal Character when trying to compile java code

That's a byte order mark, as everyone says.

javac does not understand the BOM, not even when you try something like

javac -encoding UTF8

You need to strip the BOM or convert your source file to another encoding. Notepad++ can convert a single files encoding, I'm not aware of a batch utility on the Windows platform for this.

The java compiler will assume the file is in your platform default encoding, so if you use this, you don't have to specify the encoding.

BAT file to open CMD in current directory

As a more general solution you might want to check out the Microsoft Power Toy for XP that adds the "Open Command Window Here" option when you right-click:

In Vista and Windows 7, you'll get that option if you hold down shift and right-click (this is built in).

Pandas rename column by position?

You can do this:

df.rename(columns={ df.columns[1]: "whatever" })

Forcing to download a file using PHP

Here is a more browser-safe solution:

    $fp = @fopen($yourfile, 'rb');

    if (strstr($_SERVER['HTTP_USER_AGENT'], "MSIE"))
    header('Content-Type: "application/octet-stream"');
    header('Content-Disposition: attachment; filename="yourname.file"');
    header('Expires: 0');
    header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
    header("Content-Transfer-Encoding: binary");
    header('Pragma: public');
    header("Content-Length: ".filesize($yourfile));
    header('Content-Type: "application/octet-stream"');
    header('Content-Disposition: attachment; filename="yourname.file"');
    header("Content-Transfer-Encoding: binary");
    header('Expires: 0');
    header('Pragma: no-cache');
    header("Content-Length: ".filesize($yourfile));


JSP tricks to make templating easier?

As skaffman suggested, JSP 2.0 Tag Files are the bee's knees.

Let's take your simple example.

Put the following in WEB-INF/tags/wrapper.tag

<%@tag description="Simple Wrapper Tag" pageEncoding="UTF-8"%>

Now in your example.jsp page:

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags" %>


That does exactly what you think it does.

So, lets expand upon that to something a bit more general. WEB-INF/tags/genericpage.tag

<%@tag description="Overall Page template" pageEncoding="UTF-8"%>
<%@attribute name="header" fragment="true" %>
<%@attribute name="footer" fragment="true" %>
    <div id="pageheader">
      <jsp:invoke fragment="header"/>
    <div id="body">
    <div id="pagefooter">
      <jsp:invoke fragment="footer"/>

To use this:

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags" %>

    <jsp:attribute name="header">
    <jsp:attribute name="footer">
      <p id="copyright">Copyright 1927, Future Bits When There Be Bits Inc.</p>
        <p>Hi I'm the heart of the message</p>

What does that buy you? A lot really, but it gets even better...


<%@tag description="User Page template" pageEncoding="UTF-8"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags" %>
<%@attribute name="userName" required="true"%>

    <jsp:attribute name="header">
      <h1>Welcome ${userName}</h1>
    <jsp:attribute name="footer">
      <p id="copyright">Copyright 1927, Future Bits When There Be Bits Inc.</p>

To use this: (assume we have a user variable in the request)

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags" %>

<t:userpage userName="${user.fullName}">
    First Name: ${user.firstName} <br/>
    Last Name: ${user.lastName} <br/>
    Phone: ${}<br/>

But it turns you like to use that user detail block in other places. So, we'll refactor it. WEB-INF/tags/userdetail.tag

<%@tag description="User Page template" pageEncoding="UTF-8"%>
<%@tag import="com.example.User" %>
<%@attribute name="user" required="true" type="com.example.User"%>

First Name: ${user.firstName} <br/>
Last Name: ${user.lastName} <br/>
Phone: ${}<br/>

Now the previous example becomes:

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags" %>

<t:userpage userName="${user.fullName}">
    <t:userdetail user="${user}"/>

The beauty of JSP Tag files is that it lets you basically tag generic markup and then refactor it to your heart's content.

JSP Tag Files have pretty much usurped things like Tiles etc., at least for me. I find them much easier to use as the only structure is what you give it, nothing preconceived. Plus you can use JSP tag files for other things (like the user detail fragment above).

Here's an example that is similar to DisplayTag that I've done, but this is all done with Tag Files (and the Stripes framework, that's the s: tags..). This results in a table of rows, alternating colors, page navigation, etc:

<t:table items="${actionBean.customerList}" var="obj" css_class="display">
  <t:col css_class="checkboxcol">
    <s:checkbox name="customerIds" value="${obj.customerId}"
                onclick="handleCheckboxRangeSelection(this, event);"/>
  <t:col name="customerId" title="ID"/>
  <t:col name="firstName" title="First Name"/>
  <t:col name="lastName" title="Last Name"/>
    <s:link href="/Customer.action" event="preEdit">
      <s:param name="customer.customerId" value="${obj.customerId}"/>
      <s:param name="page" value="${}"/>

Of course the tags work with the JSTL tags (like c:if, etc.). The only thing you can't do within the body of a tag file tag is add Java scriptlet code, but this isn't as much of a limitation as you might think. If I need scriptlet stuff, I just put the logic in to a tag and drop the tag in. Easy.

So, tag files can be pretty much whatever you want them to be. At the most basic level, it's simple cut and paste refactoring. Grab a chunk of layout, cut it out, do some simple parameterization, and replace it with a tag invocation.

At a higher level, you can do sophisticated things like this table tag I have here.

Found conflicts between different versions of the same dependent assembly that could not be resolved

Changing the build verbosity in visual studio will help to point in the right direction. Follow the below steps to change verbosity in VS

  1. Go to Tools->Options menu in VS
  2. Open Projects and Solutions->Build and Run
  3. Change the value of the MSBuild project build output verbosity. Pick one from Quiet, Minimal, Normal, Detailed and Diagnostic

Check the output window(Ctrl+Alt+O) in VS to see the changes in the build log.

Where in memory are my variables stored in C?

pointers(ex:char *arr,int *arr) -------> heap

Nope, they can be on the stack or in the data segment. They can point anywhere.

Escape text for HTML

.NET 4.0 and above:

using System.Web.Security.AntiXss;
var encoded = AntiXssEncoder.HtmlEncode("input", useNamedEntities: true);

Blur or dim background when Android PopupWindow active

The question was about the Popupwindow class, yet everybody has given answers that use the Dialog class. Thats pretty much useless if you need to use the Popupwindow class, because Popupwindow doesn't have a getWindow() method.

I've found a solution that actually works with Popupwindow. It only requires that the root of the xml file you use for the background activity is a FrameLayout. You can give the Framelayout element an android:foreground tag. What this tag does is specify a drawable resource that will be layered on top of the entire activity (that is, if the Framelayout is the root element in the xml file). You can then control the opacity (setAlpha()) of the foreground drawable.

You can use any drawable resource you like, but if you just want a dimming effect, create an xml file in the drawable folder with the <shape> tag as root.

<?xml version="1.0" encoding="utf-8"?>
    android:shape="rectangle" >
    <solid android:color="#000000" />

(See for more info on the shape element). Note that I didn't specify an alpha value in the color tag that would make the drawable item transparent (e.g #ff000000). The reason for this is that any hardcoded alpha value seems to override any new alpha values we set via the setAlpha() in our code, so we don't want that. However, that means that the drawable item will initially be opaque (solid, non-transparent). So we need to make it transparent in the activity's onCreate() method.

Here's the Framelayout xml element code:

    android:foreground="@drawable/shape_window_dim" >
... your activity's content

Here's the Activity's onCreate() method:

public void onCreate( Bundle savedInstanceState)
  super.onCreate( savedInstanceState);

  setContentView( R.layout.activity_mainmenu);

  // Your own Activity initialization code

  layout_MainMenu = (FrameLayout) findViewById(;
  layout_MainMenu.getForeground().setAlpha( 0);

Finally, the code to dim the activity:

layout_MainMenu.getForeground().setAlpha( 220); // dim

layout_MainMenu.getForeground().setAlpha( 0); // restore

The alpha values go from 0 (opaque) to 255 (invisible). You should un-dim the activity when you dismiss the Popupwindow.

I haven't included code for showing and dismissing the Popupwindow, but here's a link to how it can be done:

Table 'mysql.user' doesn't exist:ERROR

Your database may be corrupt. Try to check if mysql.user exists:

use mysql;
select * from user;

If these are missing you can try recreating the tables by using


or you may have to clean (completely remove it) and reinstall MySQL.

WCF Exception: Could not find a base address that matches scheme http for the endpoint

I tried the binding according to the answer by @Szymon but It did not work for me. I tried basicHttpsBinding which is new in .net 4.5 and It solved the issue. Here is the complete configuration that works for me.

    <serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="false" />
          <serviceMetadata httpGetEnabled="false" httpsGetEnabled="true"/>
          <serviceDebug includeExceptionDetailInFaults="true"/>
        <binding name="basicHttpsBindingForYourService">
          <security mode="Transport">
            <transport clientCredentialType="None" proxyCredentialType="None"/>
      <service name="YourServiceName">
        <endpoint address="" binding="basicHttpsBinding" bindingName="basicHttpsBindingForYourService" contract="YourContract" />

FYI: My application's target framework is 4.5.1. IIS web site that I created to deploy this wcf service only has https binding enabled.

How to iterate over array of objects in Handlebars?

I had a similar issue I was getting the entire object in this but the value was displaying while doing #each.

Solution: I re-structure my array of object like this:

let list =>{
    return {, }

and then in template file:

{{#each list}}
        <td>{{name }}</td>

JQuery - Set Attribute value

Some things before the actual code..

the hash (#) you use as the selector is for IDs and not for names of elements. also the disabled attribute is not a true false scenario .. if it has disabled attribute it means that it is true .. you need to remove the attribute and not set it to false. Also there are the form selectors that identify specific types of items in a form ..

so the code would be


Bringing the answer up-to-date

You should use the .prop() method (added since v1.6)

$("input:checkbox[name='chk0']").prop('disabled', false); // to enable the checkbox


$("input:checkbox[name='chk0']").prop('disabled', true); // to disable the checkbox

Angular HTTP GET with TypeScript error http.get(...).map is not a function in [null]

I tried below commands and it gets fixed:

npm install rxjs@6 rxjs-compat@6 --save

import 'rxjs/Rx'; /storage/emulated/0/New file.txt: open failed: EACCES (Permission denied)

If you are running in Android 29 then you have to use scoped storage or for now, you can bypass this issue by using:


in manifest in the application tag.

How to print to console in pytest?

I needed to print important warning about skipped tests exactly when PyTest muted literally everything.

I didn't want to fail a test to send a signal, so I did a hack as follow:

def test_2_YellAboutBrokenAndMutedTests():
    import atexit
    def report():
        print C_patch.tidy_text("""
In silent mode PyTest breaks low level stream structure I work with, so
I cannot test if my functionality work fine. I skipped corresponding tests.
Run `py.test -s` to make sure everything is tested.""")
    if sys.stdout != sys.__stdout__:

The atexit module allows me to print stuff after PyTest released the output streams. The output looks as follow:

============================= test session starts ==============================
platform linux2 -- Python 2.7.3, pytest-2.9.2, py-1.4.31, pluggy-0.3.1
rootdir: /media/Storage/henaro/smyth/Alchemist2-git/sources/C_patch, inifile: 
collected 15 items .....ssss....s.

===================== 10 passed, 5 skipped in 0.15 seconds =====================
In silent mode PyTest breaks low level stream structure I work with, so
I cannot test if my functionality work fine. I skipped corresponding tests.
Run `py.test -s` to make sure everything is tested.

Message is printed even when PyTest is in silent mode, and is not printed if you run stuff with py.test -s, so everything is tested nicely already.

How to get text from each cell of an HTML table?

I have not used Selenium 2. Selenium 1.x has selenium.getTable("tablename".columnNumber.rowNumber) to reach the required cell. May be you can use webdriverbackedselenium and do this.

And you can get the total rows and columns by using

int numOfRows = selenium.getXpathCount("//table[@id='tableid']//tr")

int numOfCols=selenium.getXpathCount("//table[@id='tableid']//tr//td")

Why use deflate instead of gzip for text files served by Apache?

if I remember correctly

  • gzip will compress a little more than deflate
  • deflate is more efficient

How to calculate moving average without keeping the count and data-total?

The answer of Flip is computationally more consistent than the Muis one.

Using double number format, you could see the roundoff problem in the Muis approach:

The Muis approach

When you divide and subtract, a roundoff appears in the previous stored value, changing it.

However, the Flip approach preserves the stored value and reduces the number of divisions, hence, reducing the roundoff, and minimizing the error propagated to the stored value. Adding only will bring up roundoffs if there is something to add (when N is big, there is nothing to add)

The Flip approach

Those changes are remarkable when you make a mean of big values tend their mean to zero.

I show you the results using a spreadsheet program:

Firstly, the results obtained: Results

The A and B columns are the n and X_n values, respectively.

The C column is the Flip approach, and the D one is the Muis approach, the result stored in the mean. The E column corresponds with the medium value used in the computation.

A graph showing the mean of even values is the next one:


As you can see, there is big differences between both approachs.

How to replace NA values in a table for selected columns

This is now trivial in tidyr with replace_na(). The function appears to work for data.tables as well as data.frames:

tidyr::replace_na(x, list(a=0, b=0))

Know relationships between all the tables of database in SQL Server

Sometimes, a textual representation might also help; with this query on the system catalog views, you can get a list of all FK relationships and how the link two tables (and what columns they operate on).

SELECT 'FK Name', 'Parent table',, cp.column_id, 'Refrenced table',, cr.column_id
    sys.foreign_keys fk
    sys.tables tp ON fk.parent_object_id = tp.object_id
    sys.tables tr ON fk.referenced_object_id = tr.object_id
    sys.foreign_key_columns fkc ON fkc.constraint_object_id = fk.object_id
    sys.columns cp ON fkc.parent_column_id = cp.column_id AND fkc.parent_object_id = cp.object_id
    sys.columns cr ON fkc.referenced_column_id = cr.column_id AND fkc.referenced_object_id = cr.object_id
ORDER BY, cp.column_id

Dump this into Excel, and you can slice and dice - based on the parent table, the referenced table or anything else.

I find visual guides helpful - but sometimes, textual documentation is just as good (or even better) - just my 2 cents.....

How can I get phone serial number (IMEI)

try this

 final TelephonyManager tm =(TelephonyManager)getBaseContext().getSystemService(Context.TELEPHONY_SERVICE);

  String deviceid = tm.getDeviceId();

Javascript to convert UTC to local time

Here is another option that outputs mm/dd/yy:

const date = new Date('2012-11-29 17:00:34 UTC');
//output 11/29/2012

How can I execute a PHP function in a form action?

It's better something like the data to the self page and maybe do a check on user input.

    require_once ( 'username.php' );

    if(isset($_POST)) {
      echo "form post"; // ex $_POST['textfield']

    echo '
    <form name="form1" method="post" action="' . $_SERVER['PHP_SELF'] . '">
          <input type="text" name="textfield" id="textfield">
          <input type="submit" name="button" id="button" value="Submit">

System.MissingMethodException: Method not found?

In my case, there was no code change at all and suddenly one of the servers started getting this and only this exception (all servers have the same code, but only one started having issues):

System.MissingMethodException: Method not found: '?'.


Server stack trace: 
   at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation)
   at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message)

Exception rethrown at [0]: 
   at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
   at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
   at myAccountSearch.AccountSearch.searchtPhone(searchtPhoneRequest request)
   at myAccountSearch.AccountSearchClient.myAccountSearch.AccountSearch.searchtPhone(searchtPhoneRequest request)
   at myAccountSearch.AccountSearchClient.searchtPhone(String ID, String HashID, searchtPhone Phone1)
   at WS.MyValidation(String AccountNumber, String PhoneNumber)

The issue I believe was corrupted AppPool - we have automated AppPool recycling going on every day at 3 am and the issue started at 3 am and then ended on its own at 3 am the next day.

C# - Substring: index and length must refer to a location within the string

You need to check your statement like this :

string url = "";
string lenght = url.Lenght-4;
if(url.Lenght > 15)//eg 15
 string newString = url.Substring(18, lenght);

SQL Server : Transpose rows to columns

SQL Server has a PIVOT command that might be what you are looking for.

select * from Tag
pivot (MAX(Value) for TagID in ([A1],[A2],[A3],[A4])) as TagTime;

If the columns are not constant, you'll have to combine this with some dynamic SQL.


select @columns = substring((Select DISTINCT ',' + QUOTENAME(TagID) FROM Tag FOR XML PATH ('')),2, 1000);

SELECT @sql =

  FOR TagID IN( ' + @columns + ' )) as TagTime;';


Kendo grid date column not formatting

This might be helpful:

columns.Bound(date=> date.START_DATE).Title("Start Date").Format("{0:MM dd, yyyy}");

Replace duplicate spaces with a single space in T-SQL

You can try this:

select Regexp_Replace('single    spaces   only','( ){2,}', ' ') from dual;

Gradle failed to resolve library in Android Studio

Check to see if your gradle is offline. Preferences-ProjectSettings-Gradle. If you're trying to add a library while offline, you'll see that error. Also, try Build-Clean, it may provide you with more detail.

jQuery form input select by id

Why not just:

$('#b').click(function () {
    var val = $(this).val(); 

Or if you don't click it (and I guess you won't) and you will use submit button, you can use prev() function either.

Uploading Images to Server android

Intent photoPickerIntent = new Intent(Intent.ACTION_PICK);
startActivityForResult(photoPickerIntent, 1);


public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == 1)
        if (resultCode == Activity.RESULT_OK) {
            Uri selectedImage = data.getData();

            String filePath = getPath(selectedImage);
            String file_extn = filePath.substring(filePath.lastIndexOf(".") + 1);

            try {
                if (file_extn.equals("img") || file_extn.equals("jpg") || file_extn.equals("jpeg") || file_extn.equals("gif") || file_extn.equals("png")) {
                } else {
                    //NOT IN REQUIRED FORMAT
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block

public String getPath(Uri uri) {
    String[] projection = {MediaColumns.DATA};
    Cursor cursor = managedQuery(uri, projection, null, null, null);
    column_index = cursor
    imagePath = cursor.getString(column_index);

    return cursor.getString(column_index);


HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("LINK TO SERVER");

Multipart FORM DATA

MultipartEntity mpEntity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
if (filePath != null) {
    File file = new File(filePath);
    Log.d("EDIT USER PROFILE", "UPLOAD: file length = " + file.length());
    Log.d("EDIT USER PROFILE", "UPLOAD: file exist = " + file.exists());
    mpEntity.addPart("avatar", new FileBody(file, "application/octet"));


HttpResponse response = httpclient.execute(httppost);

How to convert a char to a String?

Below are various ways to convert to char c to String s (in decreasing order of speed and efficiency)

char c = 'a';
String s = String.valueOf(c);             // fastest + memory efficient
String s = Character.toString(c);
String s = new String(new char[]{c});
String s = String.valueOf(new char[]{c});
String s = new Character(c).toString();
String s = "" + c;                        // slowest + memory inefficient

Vue.js redirection to another page

just use:

window.location.href = ""

Don't use vue-router, otherwise you will be redirected to "!/"

my environment: node 6.2.1, vue 1.0.21, Ubuntu.

Handle spring security authentication exceptions with @ExceptionHandler

Taking answers from @Nicola and @Victor Wing and adding a more standardized way:

import org.springframework.beans.factory.InitializingBean;
import org.springframework.http.HttpStatus;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpResponse;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class UnauthorizedErrorAuthenticationEntryPoint implements AuthenticationEntryPoint, InitializingBean {

    private HttpMessageConverter messageConverter;

    public void commence(HttpServletRequest request, HttpServletResponse response, AuthenticationException exception) throws IOException, ServletException {

        MyGenericError error = new MyGenericError();

        ServerHttpResponse outputMessage = new ServletServerHttpResponse(response);

        messageConverter.write(error, null, outputMessage);

    public void setMessageConverter(HttpMessageConverter messageConverter) {
        this.messageConverter = messageConverter;

    public void afterPropertiesSet() throws Exception {

        if (messageConverter == null) {
            throw new IllegalArgumentException("Property 'messageConverter' is required");


Now, you can inject configured Jackson, Jaxb or whatever you use to convert response bodies on your MVC annotation or XML based configuration with its serializers, deserializers and so on.

nodejs npm global config missing on windows

Have you tried running npm config list? And, if you want to see the defaults, run npm config ls -l.

Add alternating row color to SQL Server Reporting services report

I think this trick is not discussed here. So here it is,

In any type of complex matrix, when you want alternate cell colors, either row wise or column wise, the working solution is,

If you want a alternate color of cells coloumn wise then,

  1. At the bottom right corner of a report design view, in "Column Groups", create a fake parent group on 1 (using expression), named "FakeParentGroup".
  2. Then, in the report design, for cells that to be colored alternatively, use following background color expression

=IIF(RunningValue( Fields![ColumnGroupField].Value, countDistinct, "FakeParentGroup" ) MOD 2, "White", "LightGrey")

Thats all.

Same for the alternate color row wise, just you have to edit solution accordingly.

NOTE: Here, sometimes you need to set border of cells accordingly, usually it vanishes.

Also dont forget to delete value 1 in report that came into pic when you created fake parent group.

app.config for a class library

I don't know why this answer hasn't already been given:

Different callers of the same library will, in general, use different configurations. This implies that the configuration must reside in the executable application, and not in the class library.

You may create an app.config within the class library project. It will contain default configurations for items you create within the library. For instance, it will contain connection strings if you create an Entity Framework model within the class library.

However, these settings will not be used by the executable application calling the library. Instead, these settings may be copied from the library.dll.config file into the app.config or web.config of the caller, so that they may be changed to be specific to the caller, and to the environment into which the caller is deployed.

This is how it has been with .NET since Day 1.

Http post and get request in angular 6

For reading full response in Angular you should add the observe option:

{ observe: 'response' }
    return this.http.get(`${environment.serverUrl}/api/posts/${postId}/comments/?page=${page}&size=${size}`, { observe: 'response' });

How can I get a list of locally installed Python modules?

Since pip version 1.3, you've got access to:

pip list

Which seems to be syntactic sugar for "pip freeze". It will list all of the modules particular to your installation or virtualenv, along with their version numbers. Unfortunately it does not display the current version number of any module, nor does it wash your dishes or shine your shoes.

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '''')' at line 2

There is a single quote in $submitsubject or $submit_message

Why is this a problem?

The single quote char terminates the string in MySQL and everything past that is treated as a sql command. You REALLY don't want to write your sql like that. At best, your application will break intermittently (as you're observing) and at worst, you have just introduced a huge security vulnerability.

Imagine if someone submitted '); DROP TABLE private_messages; in submit message.

Your SQL Command would be:

INSERT INTO private_messages (to_id, from_id, time_sent, subject, message) 
        VALUES('sender_id', 'id', now(),'subjet','');

DROP TABLE private_messages;

Instead you need to properly sanitize your values.

AT A MINIMUM you must run each value through mysql_real_escape_string() but you should really be using prepared statements.

If you were using mysql_real_escape_string() your code would look like this:


    $submit_subject="(no subject)";
$sender_id = mysql_real_escape_string($_POST['sender_id']);

Here is a great article on prepared statements and PDO.

Check if string ends with certain pattern

Of course you can use the StringTokenizer class to split the String with '.' or '/', and check if the last word is "work".

Communication between tabs or windows

Edit 2018: You may better use BroadcastChannel for this purpose, see other answers below. Yet if you still prefer to use localstorage for communication between tabs, do it this way:

In order to get notified when a tab sends a message to other tabs, you simply need to bind on 'storage' event. In all tabs, do this:

$(window).on('storage', message_receive);

The function message_receive will be called every time you set any value of localStorage in any other tab. The event listener contains also the data newly set to localStorage, so you don't even need to parse localStorage object itself. This is very handy because you can reset the value just right after it was set, to effectively clean up any traces. Here are functions for messaging:

// use local storage for messaging. Set message in local storage and clear it right away
// This is a safe way how to communicate with other tabs while not leaving any traces
function message_broadcast(message)

// receive message
function message_receive(ev)
    if (ev.originalEvent.key!='message') return; // ignore other keys
    var message=JSON.parse(ev.originalEvent.newValue);
    if (!message) return; // ignore empty msg or msg reset

    // here you act on messages.
    // you can send objects like { 'command': 'doit', 'data': 'abcd' }
    if (message.command == 'doit') alert(;

    // etc.

So now once your tabs bind on the onstorage event, and you have these two functions implemented, you can simply broadcast a message to other tabs calling, for example:


Remember that sending the exact same message twice will be propagated only once, so if you need to repeat messages, add some unique identifier to them, like

message_broadcast({'command':'reset', 'uid': (new Date).getTime()+Math.random()})

Also remember that the current tab which broadcasts the message doesn't actually receive it, only other tabs or windows on the same domain.

You may ask what happens if the user loads a different webpage or closes his tab just after the setItem() call before the removeItem(). Well, from my own testing the browser puts unloading on hold until the entire function message_broadcast() is finished. I tested to put inthere some very long for() cycle and it still waited for the cycle to finish before closing. If the user kills the tab just inbetween, then the browser won't have enough time to save the message to disk, thus this approach seems to me like safe way how to send messages without any traces. Comments welcome.

what is Ljava.lang.String;@

I also met this problem when I've made ListView for android app:

Map<String, Object> m;

for(int i=0; i < dates.length; i++){
    m = new HashMap<String, Object>();
    m.put(ATTR_DATES, dates[i]);
    m.put(ATTR_SQUATS, squats[i]);
    m.put(ATTR_BP, benchpress[i]);
    m.put(ATTR_ROW, row[i]);

The problem was that I've forgotten to use the [i] index inside the loop

Cannot perform runtime binding on a null reference, But it is NOT a null reference

This exception is also thrown when a non-existent property is being updated dynamically, using reflection.

If one is using reflection to dynamically update property values, it's worth checking to make sure the passed PropertyName is identical to the actual property.

In my case, I was attempting to update Employee.firstName, but the property was actually Employee.FirstName.

Worth keeping in mind. :)

Location Services not working in iOS 8

I was pulling my hair out with the same problem. Xcode gives you the error:

Trying to start MapKit location updates without prompting for location authorization. Must call -[CLLocationManager requestWhenInUseAuthorization] or -[CLLocationManager requestAlwaysAuthorization] first.

But even if you implement one of the above methods, it won't prompt the user unless there is an entry in the info.plist for NSLocationAlwaysUsageDescription or NSLocationWhenInUseUsageDescription.

Add the following lines to your info.plist where the string values represent the reason you you need to access the users location

<string>This application requires location services to work</string>

<string>This application requires location services to work</string>

I think these entries may have been missing since I started this project in Xcode 5. I'm guessing Xcode 6 might add default entries for these keys but have not confirmed.

You can find more information on these two Settings here

How do I invert BooleanToVisibilityConverter?

I know this is dated, but, you don't need to re-implement anything.

What I did was to negate the value on the property like this:

<!-- XAML code -->
<StackPanel Name="x"  Visibility="{Binding    Path=Specials, ElementName=MyWindow, Converter={StaticResource BooleanToVisibilityConverter}}"></StackPanel>    
<StackPanel Name="y"  Visibility="{Binding Path=NotSpecials, ElementName=MyWindow, Converter={StaticResource BooleanToVisibilityConverter}}"></StackPanel>        


//Code behind
public bool Specials
    get { return (bool) GetValue(SpecialsProperty); }
        NotSpecials= !value; 
        SetValue(SpecialsProperty, value);

public bool NotSpecials
    get { return (bool) GetValue(NotSpecialsProperty); }
    set { SetValue(NotSpecialsProperty, value); }

And it works just fine!

Am I missing something?

How to get the file name from a full path using JavaScript?

A question asking "get file name without extension" refer to here but no solution for that. Here is the solution modified from Bobbie's solution.

var name_without_ext = (file_name.split('\\').pop().split('/').pop().split('.'))[0];

Is there a "goto" statement in bash?

Although others have already clarified that there is no direct goto equivalent in bash (and provided the closest alternatives such as functions, loops, and break), I would like to illustrate how using a loop plus break can simulate a specific type of goto statement.

The situation where I find this the most useful is when I need to return to the beginning of a section of code if certain conditions are not met. In the example below, the while loop will run forever until ping stops dropping packets to a test IP.



# Loop forever (until break is issued)
while true; do

    # Do a simple test for Internet connectivity
    PacketLoss=$(ping "$TestIP" -c 2 | grep -Eo "[0-9]+% packet loss" | grep -Eo "^[0-9]")

    # Exit the loop if ping is no longer dropping packets
    if [ "$PacketLoss" == 0 ]; then
        echo "Connection restored"
        echo "No connectivity"

apc vs eaccelerator vs xcache

Even both eacceleator and xcache perform quite well during moderate loads, APC maintains its stability under serious request intensity. If we're talking about a few hundred requests/sec here, you'll not feel the difference. But if you're trying to respond more, definetely stick with APC. Especially if your application has overly dynamic characteristics which will likely cause locking issues under such loads. may help.

C99 stdint.h header and MS Visual Studio

Microsoft do not support C99 and haven't announced any plans to. I believe they intend to track C++ standards but consider C as effectively obsolete except as a subset of C++.

New projects in Visual Studio 2003 and later have the "Compile as C++ Code (/TP)" option set by default, so any .c files will be compiled as C++.

How can I tell if a Java integer is null?

For me just using the Integer.toString() method works for me just fine. You can convert it over if you just want to very if it is null. Example below:

private void setCarColor(int redIn, int blueIn, int greenIn)
//Integer s = null;
if (Integer.toString(redIn) == null || Integer.toString(blueIn) == null ||     Integer.toString(greenIn) == null )

How to Lock the data in a cell in excel using vba

Let's say for example in one case, if you want to locked cells from range A1 to I50 then below is the code:

Worksheets("Enter your sheet name").Range("A1:I50").Locked = True
ActiveSheet.Protect Password:="Enter your Password"

In another case if you already have a protected sheet then follow below code:

ActiveSheet.Unprotect Password:="Enter your Password"
Worksheets("Enter your sheet name").Range("A1:I50").Locked = True
ActiveSheet.Protect Password:="Enter your Password"

Gradle - Move a folder from ABC to XYZ

Your task declaration is incorrectly combining the Copy task type and project.copy method, resulting in a task that has nothing to copy and thus never runs. Besides, Copy isn't the right choice for renaming a directory. There is no Gradle API for renaming, but a bit of Groovy code (leveraging Java's File API) will do. Assuming Project1 is the project directory:

task renABCToXYZ {     doLast {         file("ABC").renameTo(file("XYZ"))     } } 

Looking at the bigger picture, it's probably better to add the renaming logic (i.e. the doLast task action) to the task that produces ABC.

How to get the Touch position in android?

public boolean onTouchEvent(MotionEvent event)
    int x = (int)event.getX();
    int y = (int)event.getY();

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
        case MotionEvent.ACTION_MOVE:
        case MotionEvent.ACTION_UP:

    return false;

The three cases are so that you can react to different types of events, in this example tapping or dragging or lifting the finger again.

Pushing empty commits to remote

 $ git commit --allow-empty -m "Trigger Build"

How to check file input size with jQuery?

Use below to check file's size and clear if it's greater,

    $("input[type='file']").on("change", function () {
     if(this.files[0].size > 2000000) {
       alert("Please upload file less than 2MB. Thanks!!");

raw_input function in Python

The "input" function converts the input you enter as if it were python code. "raw_input" doesn't convert the input and takes the input as it is given. Its advisable to use raw_input for everything. Usage:

>>a = raw_input()

calculating execution time in c++

If you have cygwin installed, from it's bash shell, run your executable, say MyProgram, using the time utility, like so:

/usr/bin/time ./MyProgram

This will report how long the execution of your program took -- the output would look something like the following:

real    0m0.792s
user    0m0.046s
sys     0m0.218s

You could also manually modify your C program to instrument it using the clock() library function, like so:

#include <time.h>
int main(void) {
    clock_t tStart = clock();
    /* Do your stuff here */
    printf("Time taken: %.2fs\n", (double)(clock() - tStart)/CLOCKS_PER_SEC);
    return 0;

Get the Year/Month/Day from a datetime in php?

Try below code if you want to use php loop to display

  <select name="birth_month">
    <?php for( $m=1; $m<=12; ++$m ) { 
      $month_label = date('F', mktime(0, 0, 0, $m, 1));
      <option value="<?php echo $month_label; ?>"><?php echo $month_label; ?></option>
    <?php } ?>
  <select name="birth_day">
      $start_date = 1;
      $end_date   = 31;
      for( $j=$start_date; $j<=$end_date; $j++ ) {
        echo '<option value='.$j.'>'.$j.'</option>';
  <select name="birth_year">
      $year = date('Y');
      $min = $year - 60;
      $max = $year;
      for( $i=$max; $i>=$min; $i-- ) {
        echo '<option value='.$i.'>'.$i.'</option>';

How do I programmatically click a link with javascript?


Node - how to run app.js?

Just adding this. In your package.json, if your "main": "index.js" is correctly set. Just use node .

  "name": "app",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
  "devDependencies": {

Not able to install Python packages [SSL: TLSV1_ALERT_PROTOCOL_VERSION]

This worked for me. Add sudo before python

curl |sudo python

how do I loop through a line from a csv file in powershell

$header3 = @("Field_1","Field_2","Field_3","Field_4","Field_5")     

Import-Csv $fileName -Header $header3 -Delimiter "`t" | select -skip 3 | Foreach-Object {

    $record = $indexName 
    foreach ($property in $_.PSObject.Properties){

        #doSomething $property.Name, $property.Value

            if($property.Name -like '*TextWrittenAsNumber*'){

                $record = $record + "," + '"' + $property.Value + '"' 
                $record = $record + "," + $property.Value 

        $array.add($record) | out-null  
        #write-host $record                         

Write-back vs Write-Through caching?

Write-back and write-through describe policies when a write hit occurs, that is when the cache has the requested information. In these examples, we assume a single processor is writing to main memory with a cache.

Write-through: The information is written to the cache and memory, and the write finishes when both have finished. This has the advantage of being simpler to implement, and the main memory is always consistent (in sync) with the cache (for the uniprocessor case - if some other device modifies main memory, then this policy is not enough), and a read miss never results in writes to main memory. The obvious disadvantage is that every write hit has to do two writes, one of which accesses slower main memory.

Write-back: The information is written to a block in the cache. The modified cache block is only written to memory when it is replaced (in effect, a lazy write). A special bit for each cache block, the dirty bit, marks whether or not the cache block has been modified while in the cache. If the dirty bit is not set, the cache block is "clean" and a write miss does not have to write the block to memory.

The advantage is that writes can occur at the speed of the cache, and if writing within the same block only one write to main memory is needed (when the previous block is being replaced). The disadvantages are that this protocol is harder to implement, main memory can be not consistent (not in sync) with the cache, and reads that result in replacement may cause writes of dirty blocks to main memory.

The policies for a write miss are detailed in my first link.

These protocols don't take care of the cases with multiple processors and multiple caches, as is common in modern processors. For this, more complicated cache coherence mechanisms are required. Write-through caches have simpler protocols since a write to the cache is immediately reflected in memory.

Good resources:

Address validation using Google Maps API

Google basis (free) does not provide address verification (Geocoding) as there is no UK postcode license.

This means postcode searches are very in-accurate. The proximity search is very poor, even for town searches, often not recognising locations.

This is why Google have a premier and a enterprise solution which still is more expensive and not as good as business mapping specialists like bIng and Via Michelin who also have API's.

As a free lance developer, so serious business would use Google as the system is weak and really provides a watered down solution.

need to add a class to an element

You can use result.className = 'red';, but you can also use result.classList.add('red');. The .classList.add(str) way is usually easier if you need to add a class in general, and don't want to check if the class is already in the list of classes.

Docker how to change repository name or rename image?

Recently I had to migrate some images from Docker registry ( to Artifactory (

docker pull
docker tag
docker push

Preferred way of getting the selected item of a JComboBox

The first method is right.

The second method kills kittens if you attempt to do anything with x after the fact other than Object methods.

Change app language programmatically in Android

private void setLanguage(String language) {
    Locale locale = new Locale(language);
    Configuration config = new Configuration();
    } else {
        config.locale = locale;


Converting list to *args when calling function

*args just means that the function takes a number of arguments, generally of the same type.

Check out this section in the Python tutorial for more info.

Failed to load ApplicationContext (with annotation)

In my case, I had to do the following while running with Junit5

@SpringBootTest(classes = {abc.class}) @ExtendWith(SpringExtension.class

Here abc.class was the class that was being tested

How to rollback just one step using rake db:migrate

For starters

rake db:rollback will get you back one step


rake db:rollback STEP=n

Will roll you back n migrations where n is the number of recent migrations you want to rollback.

More references here.

Python - 'ascii' codec can't decode byte


encode converts a unicode object to a string object. But here you have invoked it on a string object (because you don't have the u). So python has to convert the string to a unicode object first. So it does the equivalent of


But the decode fails because the string isn't valid ascii. That's why you get a complaint about not being able to decode.

Inserting into Oracle and retrieving the generated sequence ID

Doing it as a stored procedure does have lot of advantages. You can get the sequence that is inserted into the table using syntax insert into table_name values returning.


some_seq_val  number;
lv_seq        number;
some_seq_val := your_seq.nextval;
insert into your_tab (col1, col2, col3) 
values (some_seq_val, val2, val3) returning some_seq_val into lv_seq;

dbms_output.put_line('The inserted sequence is: '||to_char(lv_seq));

Or just return some_seq_val. In case you are not making use of SEQUENCE, and arriving the sequence on some calculation, you can make use of returning into effectively.

MySQL Where DateTime is greater than today

I guess you looking for CURDATE() or NOW() .

  SELECT name, datum 
  FROM tasks 
  WHERE datum >= CURDATE()

LooK the rsult of NOW and CURDATE

   NOW()                    CURDATE()        
   2008-11-11 12:45:34      2008-11-11       

NVIDIA NVML Driver/library version mismatch

First I installed the Nvidia driver.

Next I installed cuda.

Ater that I got the "Driver/library version mismatch" ERROR but I could see the cuda version so I purged the Nvidia driver and reinstall it.

Then it worked correctly.

Get GMT Time in Java

Odds are good you did the right stuff on the back end in getting the date, but there's nothing to indicate that you didn't take that GMT time and format it according to your machine's current locale.

final Date currentTime = new Date();

final SimpleDateFormat sdf =
        new SimpleDateFormat("EEE, MMM d, yyyy hh:mm:ss a z");

// Give it to me in GMT time.
System.out.println("GMT time: " + sdf.format(currentTime));

The key is to use your own DateFormat, not the system provided one. That way you can set the DateFormat's timezone to what you wish, instead of it being set to the Locale's timezone.

Create table variable in MySQL

If you don't want to store table in database then @Evan Todd already has been provided temporary table solution.

But if you need that table for other users and want to store in db then you can use below procedure.

Create below ‘stored procedure’:



USE `test`$$

DROP PROCEDURE IF EXISTS `sp_variable_table`$$

CREATE DEFINER=`root`@`localhost` PROCEDURE `sp_variable_table`()

SELECT CONCAT(‘zafar_’,REPLACE(TIME(NOW()),’:',’_')) INTO @tbl;

SET @str=CONCAT(“create table “,@tbl,” (pbirfnum BIGINT(20) NOT NULL DEFAULT ’0', paymentModes TEXT ,paymentmodeDetails TEXT ,shippingCharges TEXT ,shippingDetails TEXT ,hypenedSkuCodes TEXT ,skuCodes TEXT ,itemDetails TEXT ,colorDesc TEXT ,size TEXT ,atmDesc TEXT ,promotional TEXT ,productSeqNumber VARCHAR(16) DEFAULT NULL,entity TEXT ,entityDetails TEXT ,kmtnmt TEXT ,rating BIGINT(1) DEFAULT NULL,discount DECIMAL(15,0) DEFAULT NULL,itemStockDetails VARCHAR(38) NOT NULL DEFAULT ”) ENGINE=INNODB DEFAULT CHARSET=utf8");
PREPARE stmt FROM @str;

SELECT ‘Table has been created’;



Now you can execute this procedure to create a variable name table as per below-

call sp_variable_table();

You can check new table after executing below command-

use test;show tables like ‘%zafar%’; — test is here ‘database’ name.

You can also check more details at below path-

how to merge 200 csv files in Python

An easy-to-use function:

def csv_merge(destination_path, *source_paths):
Merges all csv files on source_paths to destination_path.
:param destination_path: Path of a single csv file, doesn't need to exist
:param source_paths: Paths of csv files to be merged into, needs to exist
:return: None
with open(destination_path,"a") as dest_file:
    with open(source_paths[0]) as src_file:
        for src_line in
    for i in range(len(source_paths)):
        with open(source_paths[i]) as src_file:
            for src_line in src_file:

Negation in Python

The negation operator in Python is not. Therefore just replace your ! with not.

For your example, do this:

if not os.path.exists("/usr/share/sounds/blues") :
    proc = subprocess.Popen(["mkdir", "/usr/share/sounds/blues"])

For your specific example (as Neil said in the comments), you don't have to use the subprocess module, you can simply use os.mkdir() to get the result you need, with added exception handling goodness.


blues_sounds_path = "/usr/share/sounds/blues"
if not os.path.exists(blues_sounds_path):
    except OSError:
        # Handle the case where the directory could not be created.

Grid of responsive squares

I use this solution for responsive boxes of different rations:


<div class="box ratio1_1">
  <div class="box-content">
            ... CONTENT HERE ...


.box-content {
  width: 100%; height: 100%;
  top: 0;right: 0;bottom: 0;left: 0;
  position: absolute;
.box {
  position: relative;
  width: 100%;
.box::before {
    content: "";
    display: block;
    padding-top: 100%; /*square for no ratio*/
.ratio1_1::before { padding-top: 100%; }
.ratio1_2::before { padding-top: 200%; }
.ratio2_1::before { padding-top: 50%; }
.ratio4_3::before { padding-top: 75%; }
.ratio16_9::before { padding-top: 56.25%; }

See demo on

How to select lines between two marker patterns which may occur multiple times with awk/sed

From the previous response's links, the one that did it for me, running ksh on Solaris, was this:

sed '1,/firstmatch/d;/secondmatch/,$d'
  • 1,/firstmatch/d: from line 1 until the first time you find firstmatch, delete.
  • /secondmatch/,$d: from the first occurrance of secondmatch until the end of file, delete.
  • Semicolon separates the two commands, which are executed in sequence.

Convert image from PIL to openCV format

The code commented works as well, just choose which do you prefer

import numpy as np
from PIL import Image

def convert_from_cv2_to_image(img: np.ndarray) -> Image:
    # return Image.fromarray(cv2.cvtColor(img, cv2.COLOR_BGR2RGB))
    return Image.fromarray(img)

def convert_from_image_to_cv2(img: Image) -> np.ndarray:
    # return cv2.cvtColor(numpy.array(img), cv2.COLOR_RGB2BGR)
    return np.asarray(img)

How to grep, excluding some patterns?

Just use awk, it's much simpler than grep in letting you clearly express compound conditions.

If you want to skip lines that contains both loom and gloom:

awk '/loom/ && !/gloom/{ print FILENAME, FNR, $0 }' ~/projects/**/trunk/src/**/*.@(h|cpp)

or if you want to print them:

awk '/(^|[^g])loom/{ print FILENAME, FNR, $0 }' ~/projects/**/trunk/src/**/*.@(h|cpp)

and if the reality is you just want lines where loom appears as a word by itself:

awk '/\<loom\>/{ print FILENAME, FNR, $0 }' ~/projects/**/trunk/src/**/*.@(h|cpp)

PHP Parse HTML code

Use PHP Document Object Model:

   $str = '<h1>T1</h1>Lorem ipsum.<h1>T2</h1>The quick red fox...<h1>T3</h1>... jumps over the lazy brown FROG';
   $DOM = new DOMDocument;

   //get all H1
   $items = $DOM->getElementsByTagName('h1');

   //display all H1 text
   for ($i = 0; $i < $items->length; $i++)
        echo $items->item($i)->nodeValue . "<br/>";

This outputs as:


[EDIT]: After OP Clarification:

If you want the content like Lorem ipsum. etc, you can directly use this regex:

   $str = '<h1>T1</h1>Lorem ipsum.<h1>T2</h1>The quick red fox...<h1>T3</h1>... jumps over the lazy brown FROG';
   echo preg_replace("#<h1.*?>.*?</h1>#", "", $str);

this outputs:

Lorem ipsum.The quick red fox...... jumps over the lazy brown FROG

What does `unsigned` in MySQL mean and when to use it?

MySQL says:

All integer types can have an optional (nonstandard) attribute UNSIGNED. Unsigned type can be used to permit only nonnegative numbers in a column or when you need a larger upper numeric range for the column. For example, if an INT column is UNSIGNED, the size of the column's range is the same but its endpoints shift from -2147483648 and 2147483647 up to 0 and 4294967295.

When do I use it ?

Ask yourself this question: Will this field ever contain a negative value?
If the answer is no, then you want an UNSIGNED data type.

A common mistake is to use a primary key that is an auto-increment INT starting at zero, yet the type is SIGNED, in that case you’ll never touch any of the negative numbers and you are reducing the range of possible id's to half.

How can I mock requests and the response?

Try using the responses library. Here is an example from their documentation:

import responses
import requests

def test_simple():
    responses.add(responses.GET, '',
                  json={'error': 'not found'}, status=404)

    resp = requests.get('')

    assert resp.json() == {"error": "not found"}

    assert len(responses.calls) == 1
    assert responses.calls[0].request.url == ''
    assert responses.calls[0].response.text == '{"error": "not found"}'

It provides quite a nice convenience over setting up all the mocking yourself.

There's also HTTPretty:

It's not specific to requests library, more powerful in some ways though I found it doesn't lend itself so well to inspecting the requests that it intercepted, which responses does quite easily

There's also httmock.

Python - Create list with numbers between 2 values?

assuming you want to have a range between x to y


>>> range(11,17)
[11, 12, 13, 14, 15, 16]

use list for 3.x support

rsync copy over only certain types of files using include option

One more addition: if you need to sync files by its extensions in one dir only (without of recursion) you should use a construction like this:

rsync -auzv --include './' --include '*.ext' --exclude '*' /source/dir/ /destination/dir/

Pay your attention to the dot in the first --include. --no-r does not work in this construction.


Thanks to for the valuable comment!

Efficiently getting all divisors of a given number

for( int i = 1; i * i <= num; i++ )
/* upto sqrt is because every divisor after sqrt
    is also found when the number is divided by i.
   EXAMPLE like if number is 90 when it is divided by 5
    then you can also see that 90/5 = 18
    where 18 also divides the number.
   But when number is a perfect square
    then num / i == i therefore only i is the factor

How do I instantiate a Queue object in java?

Queue in Java is defined as an interface and many ready-to-use implementation is present as part of JDK release. Here are some: LinkedList, Priority Queue, ArrayBlockingQueue, ConcurrentLinkedQueue, Linked Transfer Queue, Synchronous Queue etc.

SO You can create any of these class and hold it as Queue reference. for example

import java.util.LinkedList;
import java.util.Queue;

public class QueueExample {

 public static void main (String[] args) {
  Queue que = new LinkedList();
  System.out.println("Queue Print:: " + que);
  String head = que.element();
  System.out.println("Head element:: " + head);
  String element1 = que.poll();
  System.out.println("Removed Element:: " + element1);
  System.out.println("Queue Print after poll:: " + que);
  String element2 = que.remove();
  System.out.println("Removed Element:: " + element2);
  System.out.println("Queue Print after remove:: " + que);  

You can also implement your own custom Queue implementing Queue interface.

Convert float to string with precision & number of decimal digits specified?

Here I am providing a negative example where your want to avoid when converting floating number to strings.

float num=99.463;
float tmp1=round(num*1000);
float tmp2=tmp1/1000;
cout << tmp1 << " " << tmp2 << " " << to_string(tmp2) << endl;

You get

99463 99.463 99.462997

Note: the num variable can be any value close to 99.463, you will get the same print out. The point is to avoid the convenient c++11 "to_string" function. It took me a while to get out this trap. The best way is the stringstream and sprintf methods (C language). C++11 or newer should provided a second parameter as the number of digits after the floating point to show. Right now the default is 6. I am positing this so that others won't wast time on this subject.

I wrote my first version, please let me know if you find any bug that needs to be fixed. You can control the exact behavior with the iomanipulator. My function is for showing the number of digits after the decimal point.

string ftos(float f, int nd) {
   ostringstream ostr;
   int tens = stoi("1" + string(nd, '0'));
   ostr << round(f*tens)/tens;
   return ostr.str();

How to use ternary operator in razor (specifically on HTML attributes)?

in my problem I want the text of anchor <a>text</a> inside my view to be based on some value and that text is retrieved form App string Resources

so, this @() is the solution

<a href='#'>
      @(Model.ID == 0 ? Resource_en.Back : Resource_en.Department_View_DescartChanges)

if the text is not from App string Resources use this

@(Model.ID == 0 ? "Back" :"Descart Changes")

how to convert a string to an array in php

The explode() function breaks a string into an array.

    $str = "Hello world. It's a beautiful day.";
    print_r (explode(" ",$str));

Output: Array ( [0] => Hello [1] => world. [2] => It's [3] => a [4] => beautiful [5] => day. )

Prompt for user input in PowerShell

Place this at the top of your script. It will cause the script to prompt the user for a password. The resulting password can then be used elsewhere in your script via $pw.

     [Parameter(Mandatory=$true, Position=0, HelpMessage="Password?")]

   $pw = [Runtime.InteropServices.Marshal]::PtrToStringAuto([Runtime.InteropServices.Marshal]::SecureStringToBSTR($password))

If you want to debug and see the value of the password you just read, use:

   write-host $pw

Convert String value format of YYYYMMDDHHMMSS to C# DateTime

You have to use a custom parsing string. I also suggest to include the invariant culture to identify that this format does not relate to any culture. Plus, it will prevent a warning in some code analysis tools.

var date = DateTime.ParseExact(value, "yyyyMMddHHmmss", CultureInfo.InvariantCulture);

Git - deleted some files locally, how do I get them from a remote repository

Also, I add to do the following steps so that the git repo would be correctly linked with the IDE:

 $ git reset <commit #>

 $ git checkout <file/path>

I hope this was helpful!!

How to call loading function with React useEffect only once

I like to define a mount function, it tricks EsLint in the same way useMount does and I find it more self-explanatory.

const mount = () => {
  // ...

  const unmount = () => {
    // ...
  return unmount
useEffect(mount, [])

Vertical dividers on horizontal UL menu

.last { border-right: none

.last { border-right: none !important; }

How to show form input fields based on select value?

I got its answer. Here is my code

<label for="db">Choose type</label>
<select name="dbType" id=dbType">
   <option>Choose Database Type</option>
   <option value="oracle">Oracle</option>
   <option value="mssql">MS SQL</option>
   <option value="mysql">MySQL</option>
   <option value="other">Other</option>

<div id="other" class="selectDBType" style="display:none;">
<label for="specify">Specify</label>
<input type="text" name="specify" placeholder="Specify Databse Type"/>

And my script is

$(function() {

        $('#dbType').change(function() {
            $('#' + $(this).val()).slideDown("slow");

Adding null values to arraylist

You can add nulls to the ArrayList, and you will have to check for nulls in the loop:

for(Item i : itemList) {
   if (i != null) {


itemsList.size(); would take the null into account.

 List<Integer> list = new ArrayList<Integer>();
 list.add (5);
 System.out.println (list.size());
 for (Integer value : list) {
   if (value == null)
       System.out.println ("null value");
       System.out.println (value);

Output :

null value

Negative list index?

Negative numbers mean that you count from the right instead of the left. So, list[-1] refers to the last element, list[-2] is the second-last, and so on.

How do you concatenate Lists in C#?

It also worth noting that Concat works in constant time and in constant memory. For example, the following code

        long boundary = 60000000;
        for (long i = 0; i < boundary; i++)
        var listConcat = list1.Concat(list2);
        var list = listConcat.ToList();

gives the following timing/memory metrics:

After lists filled mem used: 1048730 KB
concat two enumerables: 00:00:00.0023309 mem used: 1048730 KB
convert concat to list: 00:00:03.7430633 mem used: 2097307 KB
list1.AddRange(list2) : 00:00:00.8439870 mem used: 2621595 KB

Populating a data frame in R in a loop

I had a case in where I was needing to use a data frame within a for loop function. In this case, it was the "efficient", however, keep in mind that the database was small and the iterations in the loop were very simple. But maybe the code could be useful for some one with similar conditions.

The for loop purpose was to use the raster extract function along five locations (i.e. 5 Tokio, New York, Sau Paulo, Seul & Mexico city) and each location had their respective raster grids. I had a spatial point database with more than 1000 observations allocated within the 5 different locations and I was needing to extract information from 10 different raster grids (two grids per location). Also, for the subsequent analysis, I was not only needing the raster values but also the unique ID for each observations.

After preparing the spatial data, which included the following tasks:

  1. Import points shapefile with the readOGR function (rgdap package)
  2. Import raster files with the raster function (raster package)
  3. Stack grids from the same location into one file, with the function stack (raster package)

Here the for loop code with the use of a data frame:

1. Add stacked rasters per location into a list

raslist <- list(LOC1,LOC2,LOC3,LOC4,LOC5)

2. Create an empty dataframe, this will be the output file

TB <- data.frame(VAR1=double(),VAR2=double(),ID=character())

3. Set up for loop function

L1 <- seq(1,5,1) # the location ID is a numeric variable with values from 1 to 5 

for (i in 1:length(L1)) {
  dat=subset(points,LOCATION==i) # select corresponding points for location [i] 
  t=data.frame(extract(raslist[[i]],dat),dat$ID) # run extract function with points & raster stack for location [i]

Is there a unique Android device ID?

To understand the available Unique Ids in Android devices. Use this official guide.

Best practices for unique identifiers:

IMEI, Mac Addresses, Instance Id, GUIDs, SSAID, Advertising Id, Safety Net API to verify devices.

Android Open External Storage directory(sdcard) for storing file

The internal storage is referred to as "external storage" in the API.

As mentioned in the Environment documentation

Note: don't be confused by the word "external" here. This directory can better be thought as media/shared storage. It is a filesystem that can hold a relatively large amount of data and that is shared across all applications (does not enforce permissions). Traditionally this is an SD card, but it may also be implemented as built-in storage in a device that is distinct from the protected internal storage and can be mounted as a filesystem on a computer.

To distinguish whether "Environment.getExternalStorageDirectory()" actually returned physically internal or external storage, call Environment.isExternalStorageEmulated(). If it's emulated, than it's internal. On newer devices that have internal storage and sdcard slot Environment.getExternalStorageDirectory() will always return the internal storage. While on older devices that have only sdcard as a media storage option it will always return the sdcard.

There is no way to retrieve all storages using current Android API.

I've created a helper based on Vitaliy Polchuk's method in the answer below

How can I get the list of mounted external storage of android device

NOTE: starting KitKat secondary storage is accessible only as READ-ONLY, you may want to check for writability using the following method

 * Checks whether the StorageVolume is read-only
 * @param volume
 *            StorageVolume to check
 * @return true, if volume is mounted read-only
public static boolean isReadOnly(@NonNull final StorageVolume volume) {
    if (volume.mFile.equals(Environment.getExternalStorageDirectory())) {
        // is a primary storage, check mounted state by Environment
        return android.os.Environment.getExternalStorageState().equals(
    } else {
        if (volume.getType() == Type.USB) {
            return volume.isReadOnly();
        //is not a USB storagem so it's read-only if it's mounted read-only or if it's a KitKat device
        return volume.isReadOnly() || Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;

StorageHelper class

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.StringTokenizer;

import android.os.Environment;

public final class StorageHelper {

    //private static final String TAG = "StorageHelper";

    private StorageHelper() {

    private static final String STORAGES_ROOT;

    static {
        final String primaryStoragePath = Environment.getExternalStorageDirectory()
        final int index = primaryStoragePath.indexOf(File.separatorChar, 1);
        if (index != -1) {
            STORAGES_ROOT = primaryStoragePath.substring(0, index + 1);
        } else {
            STORAGES_ROOT = File.separator;

    private static final String[] AVOIDED_DEVICES = new String[] {
        "rootfs", "tmpfs", "dvpts", "proc", "sysfs", "none"

    private static final String[] AVOIDED_DIRECTORIES = new String[] {
        "obb", "asec"

    private static final String[] DISALLOWED_FILESYSTEMS = new String[] {
        "tmpfs", "rootfs", "romfs", "devpts", "sysfs", "proc", "cgroup", "debugfs"

     * Returns a list of mounted {@link StorageVolume}s Returned list always
     * includes a {@link StorageVolume} for
     * {@link Environment#getExternalStorageDirectory()}
     * @param includeUsb
     *            if true, will include USB storages
     * @return list of mounted {@link StorageVolume}s
    public static List<StorageVolume> getStorages(final boolean includeUsb) {
        final Map<String, List<StorageVolume>> deviceVolumeMap = new HashMap<String, List<StorageVolume>>();

        // this approach considers that all storages are mounted in the same non-root directory
        if (!STORAGES_ROOT.equals(File.separator)) {
            BufferedReader reader = null;
            try {
                reader = new BufferedReader(new FileReader("/proc/mounts"));
                String line;
                while ((line = reader.readLine()) != null) {
                    // Log.d(TAG, line);
                    final StringTokenizer tokens = new StringTokenizer(line, " ");

                    final String device = tokens.nextToken();
                    // skipped devices that are not sdcard for sure
                    if (arrayContains(AVOIDED_DEVICES, device)) {

                    // should be mounted in the same directory to which
                    // the primary external storage was mounted
                    final String path = tokens.nextToken();
                    if (!path.startsWith(STORAGES_ROOT)) {

                    // skip directories that indicate tha volume is not a storage volume
                    if (pathContainsDir(path, AVOIDED_DIRECTORIES)) {

                    final String fileSystem = tokens.nextToken();
                    // don't add ones with non-supported filesystems
                    if (arrayContains(DISALLOWED_FILESYSTEMS, fileSystem)) {

                    final File file = new File(path);
                    // skip volumes that are not accessible
                    if (!file.canRead() || !file.canExecute()) {

                    List<StorageVolume> volumes = deviceVolumeMap.get(device);
                    if (volumes == null) {
                        volumes = new ArrayList<StorageVolume>(3);
                        deviceVolumeMap.put(device, volumes);

                    final StorageVolume volume = new StorageVolume(device, file, fileSystem);
                    final StringTokenizer flags = new StringTokenizer(tokens.nextToken(), ",");
                    while (flags.hasMoreTokens()) {
                        final String token = flags.nextToken();
                        if (token.equals("rw")) {
                            volume.mReadOnly = false;
                        } else if (token.equals("ro")) {
                            volume.mReadOnly = true;

            } catch (IOException ex) {
            } finally {
                if (reader != null) {
                    try {
                    } catch (IOException ex) {
                        // ignored

        // remove volumes that are the same devices
        boolean primaryStorageIncluded = false;
        final File externalStorage = Environment.getExternalStorageDirectory();
        final List<StorageVolume> volumeList = new ArrayList<StorageVolume>();
        for (final Entry<String, List<StorageVolume>> entry : deviceVolumeMap.entrySet()) {
            final List<StorageVolume> volumes = entry.getValue();
            if (volumes.size() == 1) {
                // go ahead and add
                final StorageVolume v = volumes.get(0);
                final boolean isPrimaryStorage = v.file.equals(externalStorage);
                primaryStorageIncluded |= isPrimaryStorage;
                setTypeAndAdd(volumeList, v, includeUsb, isPrimaryStorage);
            final int volumesLength = volumes.size();
            for (int i = 0; i < volumesLength; i++) {
                final StorageVolume v = volumes.get(i);
                if (v.file.equals(externalStorage)) {
                    primaryStorageIncluded = true;
                    // add as external storage and continue
                    setTypeAndAdd(volumeList, v, includeUsb, true);
                // if that was the last one and it's not the default external
                // storage then add it as is
                if (i == volumesLength - 1) {
                    setTypeAndAdd(volumeList, v, includeUsb, false);
        // add primary storage if it was not found
        if (!primaryStorageIncluded) {
            final StorageVolume defaultExternalStorage = new StorageVolume("", externalStorage, "UNKNOWN");
            defaultExternalStorage.mEmulated = Environment.isExternalStorageEmulated();
            defaultExternalStorage.mType =
                    defaultExternalStorage.mEmulated ? StorageVolume.Type.INTERNAL
                            : StorageVolume.Type.EXTERNAL;
            defaultExternalStorage.mRemovable = Environment.isExternalStorageRemovable();
            defaultExternalStorage.mReadOnly =
            volumeList.add(0, defaultExternalStorage);
        return volumeList;

     * Sets {@link StorageVolume.Type}, removable and emulated flags and adds to
     * volumeList
     * @param volumeList
     *            List to add volume to
     * @param v
     *            volume to add to list
     * @param includeUsb
     *            if false, volume with type {@link StorageVolume.Type#USB} will
     *            not be added
     * @param asFirstItem
     *            if true, adds the volume at the beginning of the volumeList
    private static void setTypeAndAdd(final List<StorageVolume> volumeList,
            final StorageVolume v,
            final boolean includeUsb,
            final boolean asFirstItem) {
        final StorageVolume.Type type = resolveType(v);
        if (includeUsb || type != StorageVolume.Type.USB) {
            v.mType = type;
            if (v.file.equals(Environment.getExternalStorageDirectory())) {
                v.mRemovable = Environment.isExternalStorageRemovable();
            } else {
                v.mRemovable = type != StorageVolume.Type.INTERNAL;
            v.mEmulated = type == StorageVolume.Type.INTERNAL;
            if (asFirstItem) {
                volumeList.add(0, v);
            } else {

     * Resolved {@link StorageVolume} type
     * @param v
     *            {@link StorageVolume} to resolve type for
     * @return {@link StorageVolume} type
    private static StorageVolume.Type resolveType(final StorageVolume v) {
        if (v.file.equals(Environment.getExternalStorageDirectory())
                && Environment.isExternalStorageEmulated()) {
            return StorageVolume.Type.INTERNAL;
        } else if (containsIgnoreCase(v.file.getAbsolutePath(), "usb")) {
            return StorageVolume.Type.USB;
        } else {
            return StorageVolume.Type.EXTERNAL;

     * Checks whether the array contains object
     * @param array
     *            Array to check
     * @param object
     *            Object to find
     * @return true, if the given array contains the object
    private static <T> boolean arrayContains(T[] array, T object) {
        for (final T item : array) {
            if (item.equals(object)) {
                return true;
        return false;

     * Checks whether the path contains one of the directories
     * For example, if path is /one/two, it returns true input is "one" or
     * "two". Will return false if the input is one of "one/two", "/one" or
     * "/two"
     * @param path
     *            path to check for a directory
     * @param dirs
     *            directories to find
     * @return true, if the path contains one of the directories
    private static boolean pathContainsDir(final String path, final String[] dirs) {
        final StringTokenizer tokens = new StringTokenizer(path, File.separator);
        while (tokens.hasMoreElements()) {
            final String next = tokens.nextToken();
            for (final String dir : dirs) {
                if (next.equals(dir)) {
                    return true;
        return false;

     * Checks ifString contains a search String irrespective of case, handling.
     * Case-insensitivity is defined as by
     * {@link String#equalsIgnoreCase(String)}.
     * @param str
     *            the String to check, may be null
     * @param searchStr
     *            the String to find, may be null
     * @return true if the String contains the search String irrespective of
     *         case or false if not or {@code null} string input
    public static boolean containsIgnoreCase(final String str, final String searchStr) {
        if (str == null || searchStr == null) {
            return false;
        final int len = searchStr.length();
        final int max = str.length() - len;
        for (int i = 0; i <= max; i++) {
            if (str.regionMatches(true, i, searchStr, 0, len)) {
                return true;
        return false;

     * Represents storage volume information
    public static final class StorageVolume {

         * Represents {@link StorageVolume} type
        public enum Type {
             * Device built-in internal storage. Probably points to
             * {@link Environment#getExternalStorageDirectory()}

             * External storage. Probably removable, if no other
             * {@link StorageVolume} of type {@link #INTERNAL} is returned by
             * {@link StorageHelper#getStorages(boolean)}, this might be
             * pointing to {@link Environment#getExternalStorageDirectory()}

             * Removable usb storage

         * Device name
        public final String device;

         * Points to mount point of this device
        public final File file;

         * File system of this device
        public final String fileSystem;

         * if true, the storage is mounted as read-only
        private boolean mReadOnly;

         * If true, the storage is removable
        private boolean mRemovable;

         * If true, the storage is emulated
        private boolean mEmulated;

         * Type of this storage
        private Type mType;

        StorageVolume(String device, File file, String fileSystem) {
            this.device = device;
            this.file = file;
            this.fileSystem = fileSystem;

         * Returns type of this storage
         * @return Type of this storage
        public Type getType() {
            return mType;

         * Returns true if this storage is removable
         * @return true if this storage is removable
        public boolean isRemovable() {
            return mRemovable;

         * Returns true if this storage is emulated
         * @return true if this storage is emulated
        public boolean isEmulated() {
            return mEmulated;

         * Returns true if this storage is mounted as read-only
         * @return true if this storage is mounted as read-only
        public boolean isReadOnly() {
            return mReadOnly;

        public int hashCode() {
            final int prime = 31;
            int result = 1;
            result = prime * result + ((file == null) ? 0 : file.hashCode());
            return result;

         * Returns true if the other object is StorageHelper and it's
         * {@link #file} matches this one's
         * @see Object#equals(Object)
        public boolean equals(Object obj) {
            if (obj == this) {
                return true;
            if (obj == null) {
                return false;
            if (getClass() != obj.getClass()) {
                return false;
            final StorageVolume other = (StorageVolume) obj;
            if (file == null) {
                return other.file == null;
            return file.equals(other.file);

        public String toString() {
            return file.getAbsolutePath() + (mReadOnly ? " ro " : " rw ") + mType + (mRemovable ? " R " : "")
                    + (mEmulated ? " E " : "") + fileSystem;

Google Maps V3 marker with label

The way to do this without use of plugins is to make a subclass of google's OverlayView() method.

You make a custom function and apply it to the map.

function Label() { 

Now you prototype your subclass and add HTML nodes:

Label.prototype = new google.maps.OverlayView; //subclassing google's overlayView
Label.prototype.onAdd = function() {
        this.MySpecialDiv               = document.createElement('div');
        this.MySpecialDiv.className     = 'MyLabel';
        this.getPanes().overlayImage.appendChild(this.MySpecialDiv); //attach it to overlay panes so it behaves like markers


you also have to implement remove and draw functions as stated in the API docs, or this won't work.

Label.prototype.onRemove = function() {
... // remove your stuff and its events if any
Label.prototype.draw = function() {
      var position = this.getProjection().fromLatLngToDivPixel(this.get('position')); // translate map latLng coords into DOM px coords for css positioning
var pos = this.get('position');
                'top'   : position.y + 'px',
                'left'  : position.x + 'px'

That's the gist of it, you'll have to do some more work in your specific implementation.

jQuery get the image src

In my case this format worked on latest version of jQuery:


Convert/cast an stdClass object to another class

BTW: Converting is highly important if you are serialized, mainly because the de-serialization breaks the type of objects and turns into stdclass, including DateTime objects.

I updated the example of @Jadrovski, now it allows objects and arrays.


$stdobj=new StdClass();
$obj=new SomeClass();

example array

$stdobjArr=array(new StdClass(),new StdClass());
$obj[0]=new SomeClass(); // at least the first object should indicates the right class.

code: (its recursive). However, i don't know if its recursive with arrays. May be its missing an extra is_array

public static function fixCast(&$destination,$source)
    if (is_array($source)) {
        foreach($source as $sourceItem) {
            $obj = new $getClass();
    } else {
        $sourceReflection = new \ReflectionObject($source);
        $sourceProperties = $sourceReflection->getProperties();
        foreach ($sourceProperties as $sourceProperty) {
            $name = $sourceProperty->getName();
            if (is_object(@$destination->{$name})) {
                fixCast($destination->{$name}, $source->$name);
            } else {
                $destination->{$name} = $source->$name;

What does numpy.random.seed(0) do?

As noted, numpy.random.seed(0) sets the random seed to 0, so the pseudo random numbers you get from random will start from the same point. This can be good for debuging in some cases. HOWEVER, after some reading, this seems to be the wrong way to go at it, if you have threads because it is not thread safe.

from differences-between-numpy-random-and-random-random-in-python:

For numpy.random.seed(), the main difficulty is that it is not thread-safe - that is, it's not safe to use if you have many different threads of execution, because it's not guaranteed to work if two different threads are executing the function at the same time. If you're not using threads, and if you can reasonably expect that you won't need to rewrite your program this way in the future, numpy.random.seed() should be fine for testing purposes. If there's any reason to suspect that you may need threads in the future, it's much safer in the long run to do as suggested, and to make a local instance of the numpy.random.Random class. As far as I can tell, random.random.seed() is thread-safe (or at least, I haven't found any evidence to the contrary).

example of how to go about this:

from numpy.random import RandomState
prng = RandomState()
print prng.permutation(10)
prng = RandomState()
print prng.permutation(10)
prng = RandomState(42)
print prng.permutation(10)
prng = RandomState(42)
print prng.permutation(10)

may give:

[3 0 4 6 8 2 1 9 7 5]

[1 6 9 0 2 7 8 3 5 4]

[8 1 5 0 7 2 9 4 3 6]

[8 1 5 0 7 2 9 4 3 6]

Lastly, note that there might be cases where initializing to 0 (as opposed to a seed that has not all bits 0) may result to non-uniform distributions for some few first iterations because of the way xor works, but this depends on the algorithm, and is beyond my current worries and the scope of this question.

LINQ where clause with lambda expression having OR clauses and null values returning incomplete results

Try writting the lambda with the same conditions as the delegate. like this:

  List<AnalysisObject> analysisObjects = 
    (x => 
       (x.ID == packageId)
    || (x.Parent != null && x.Parent.ID == packageId)
    || (x.Parent != null && x.Parent.Parent != null && x.Parent.Parent.ID == packageId)

Get unique values from arraylist in java

you can use this for making a list Unique

ArrayList<String> listWithDuplicateValues = new ArrayList<>();

ArrayList uniqueList = (ArrayList);

PHP fwrite new line

How about you store it like this? Maybe in username:password format, so


Then you can use list($username,$password) = explode(':',file_get_contents('users.txt')); to parse the data on your end.

Difference Between Select and SelectMany

There are several overloads to SelectMany. One of them allows you to keep trace of any relationship between parent and children while traversing the hierarchy.

Example: suppose you have the following structure: League -> Teams -> Player.

You can easily return a flat collection of players. However you may lose any reference to the team the player is part of.

Fortunately there is an overload for such purpose:

var teamsAndTheirLeagues = 
         from helper in leagues.SelectMany
               ( l => l.Teams
                 , ( league, team ) => new { league, team } )
                      where > 2 
                           && helper.league.Teams.Count < 10
                           select new 
                                  { LeagueID = helper.league.ID
                                    , Team = 

The previous example is taken from Dan's IK blog. I strongly recommend you take a look at it.

How to install CocoaPods?

Simple Steps to installed pod file:

  1. Open terminal 2.Command on terminal: sudo gem install cocoapods

  2. set your project path on terminal.

  3. command : pod init

  4. go to pod file of your project and adding pod which you want to install

  5. added in pod file : pod 'AFNetworking', '~> 3.0

  6. Command : Pod install

  7. Close project of Xcode

  8. open your Project from terminals

  9. Command : open PodDemos.xcworkspace

python dictionary sorting in descending order based on values

sort dictionary 'in_dict' by value in decreasing order

sorted_dict = {r: in_dict[r] for r in sorted(in_dict, key=in_dict.get, reverse=True)}

example above

sorted_d = {r: d[r] for r in sorted(d, key=d.get('key3'), reverse=True)}

Selenium and xPath - locating a link by containing text

@FindBy(xpath = "//span[@class='y2' and contains(text(), 'Your Text')] ") 
private WebElementFacade emailLinkToVerifyAccount;

This approach will work for you, hopefully.

Why is 2 * (i * i) faster than 2 * i * i in Java?

I got similar results:

2 * (i * i): 0.458765943 s, n=119860736
2 * i * i: 0.580255126 s, n=119860736

I got the SAME results if both loops were in the same program, or each was in a separate .java file/.class, executed on a separate run.

Finally, here is a javap -c -v <.java> decompile of each:

     3: ldc           #3                  // String 2 * (i * i):
     5: invokevirtual #4                  // Method java/io/PrintStream.print:(Ljava/lang/String;)V
     8: invokestatic  #5                  // Method java/lang/System.nanoTime:()J
     8: invokestatic  #5                  // Method java/lang/System.nanoTime:()J
    11: lstore_1
    12: iconst_0
    13: istore_3
    14: iconst_0
    15: istore        4
    17: iload         4
    19: ldc           #6                  // int 1000000000
    21: if_icmpge     40
    24: iload_3
    25: iconst_2
    26: iload         4
    28: iload         4
    30: imul
    31: imul
    32: iadd
    33: istore_3
    34: iinc          4, 1
    37: goto          17


     3: ldc           #3                  // String 2 * i * i:
     5: invokevirtual #4                  // Method java/io/PrintStream.print:(Ljava/lang/String;)V
     8: invokestatic  #5                  // Method java/lang/System.nanoTime:()J
    11: lstore_1
    12: iconst_0
    13: istore_3
    14: iconst_0
    15: istore        4
    17: iload         4
    19: ldc           #6                  // int 1000000000
    21: if_icmpge     40
    24: iload_3
    25: iconst_2
    26: iload         4
    28: imul
    29: iload         4
    31: imul
    32: iadd
    33: istore_3
    34: iinc          4, 1
    37: goto          17


java -version
java version "1.8.0_121"
Java(TM) SE Runtime Environment (build 1.8.0_121-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.121-b13, mixed mode)

OpenCV - Saving images to a particular folder of choice

FOR MAC USERS if you are working with open cv

import cv2


jQuery UI 1.10: dialog and zIndex option

To sandwich an my element between the modal screen and a dialog, I need to lift my element above the modal-screen, and then lift the dialog above my element.

I had a small success by doing the following after creating the dialog on element $dlg.


Since each dialog has a different starting z-index (they incrementally get larger) I make adjustment a string with a boost value, like this:

const adjustment = "+=99";

However, jQuery just keeps increasing the zIndex value on the modal screen, so by the second dialog, the sandwich no longer worked. I gave up on ui-dialog "modal", made it "false", and just created my own modal. It imitates jQueryUI exactly. Here it is:

CoverAll = {};
CoverAll.modalDiv = null;

CoverAll.modalCloak = function(zIndex) {
  var div = CoverAll.modalDiv;
  if(!CoverAll.modalDiv) {
    div = CoverAll.modalDiv = document.createElement('div'); = '#aaaaaa';    = '0.3';   = 'fixed';        = '0';       = '0';      = '100%';     = '100%';
  if(!div.parentElement) {
  if(zIndex == null)
    zIndex = 100;  = zIndex;
  return div;

CoverAll.modalUncloak = function() {
  var div = CoverAll.modalDiv;
  if(div && div.parentElement) {
  return div;

jQuery, get ID of each element in a class using .each?

patrick dw's answer is right on.

For kicks and giggles I thought I would post a simple way to return an array of all the IDs.

var arrayOfIds = $.map($(".myClassName"), function(n, i){

Why would a " Connection timed out" exception occur when URL is up?

If the URL works fine in the web browser on the same machine, it might be that the Java code isn't using the HTTP proxy the browser is using for connecting to the URL.

href="javascript:" vs. href="javascript:void(0)"

When using javascript: in navigation the return value of the executed script, if there is one, becomes the content of a new document which is displayed in the browser. The void operator in JavaScript causes the return value of the expression following it to return undefined, which prevents this action from happening. You can try it yourself, copy the following into the address bar and press return:


The result is a new page with only the word "hello". Now change it to:

javascript:void "hello"

...nothing happens.

When you write javascript: on its own there's no script being executed, so the result of that script execution is also undefined, so the browser does nothing. This makes the following more or less equivalent:

javascript:void 0;

With the exception that undefined can be overridden by declaring a variable with the same name. Use of void 0 is generally pointless, and it's basically been whittled down from void functionThatReturnsSomething().

As others have mentioned, it's better still to use return false; in the click handler than use the javascript: protocol.

How to use sha256 in php5.3.0

A way better solution is to just use the excelent compatibility script from Anthony Ferrara:

Please, and also, when checking the password, always add a way (preferibly async, so it doesn't impact the check process for timming attacks) to update the hash if needed.

Script for rebuilding and reindexing the fragmented index?

I have found the following script is very good at maintaining indexes, you can have this scheduled to run nightly or whatever other timeframe you wish.

Remove the complete styling of an HTML button/submit

In bootstrap 4 is easiest. You can use the classes: bg-transparent and border-0

How to return dictionary keys as a list in Python?

If you need to store the keys separately, here's a solution that requires less typing than every other solution presented thus far, using Extended Iterable Unpacking (python3.x+).

newdict = {1: 0, 2: 0, 3: 0}
*k, = newdict

# [1, 2, 3]

            ¦ k = list(d)   ¦   9 characters (excluding whitespace)   ¦
            ¦ k = [*d]      ¦   6 characters                          ¦
            ¦ *k, = d       ¦   5 characters                          ¦

Interface/enum listing standard mime-type constants

I solved this with a static class:

public class MimeTypes {

    private static final HashMap<String, String> mimeTypes;

    static {
        mimeTypes = new HashMap<String, String>() {
                put(".323", "text/h323");
                put(".3g2", "video/3gpp2");
                put(".3gp", "video/3gpp");
                put(".3gp2", "video/3gpp2");
                put(".3gpp", "video/3gpp");
                put(".7z", "application/x-7z-compressed");
                put(".aa", "audio/audible");
                put(".AAC", "audio/aac");
                put(".aaf", "application/octet-stream");
                put(".aax", "audio/");
                put(".ac3", "audio/ac3");
                put(".aca", "application/octet-stream");
                put(".accda", "application/msaccess.addin");
                put(".accdb", "application/msaccess");
                put(".accdc", "application/");
                put(".accde", "application/msaccess");
                put(".accdr", "application/msaccess.runtime");
                put(".accdt", "application/msaccess");
                put(".accdw", "application/msaccess.webapplication");
                put(".accft", "application/msaccess.ftemplate");
                put(".acx", "application/internet-property-stream");
                put(".AddIn", "text/xml");
                put(".ade", "application/msaccess");
                put(".adobebridge", "application/x-bridge-url");
                put(".adp", "application/msaccess");
                put(".ADT", "audio/vnd.dlna.adts");
                put(".ADTS", "audio/aac");
                put(".afm", "application/octet-stream");
                put(".ai", "application/postscript");
                put(".aif", "audio/x-aiff");
                put(".aifc", "audio/aiff");
                put(".aiff", "audio/aiff");
                put(".air", "application/vnd.adobe.air-application-installer-package+zip");
                put(".amc", "application/x-mpeg");
                put(".application", "application/x-ms-application");
                put(".art", "image/x-jg");
                put(".asa", "application/xml");
                put(".asax", "application/xml");
                put(".ascx", "application/xml");
                put(".asd", "application/octet-stream");
                put(".asf", "video/x-ms-asf");
                put(".ashx", "application/xml");
                put(".asi", "application/octet-stream");
                put(".asm", "text/plain");
                put(".asmx", "application/xml");
                put(".aspx", "application/xml");
                put(".asr", "video/x-ms-asf");
                put(".asx", "video/x-ms-asf");
                put(".atom", "application/atom+xml");
                put(".au", "audio/basic");
                put(".avi", "video/x-msvideo");
                put(".axs", "application/olescript");
                put(".bas", "text/plain");
                put(".bcpio", "application/x-bcpio");
                put(".bin", "application/octet-stream");
                put(".bmp", "image/bmp");
                put(".c", "text/plain");
                put(".cab", "application/octet-stream");
                put(".caf", "audio/x-caf");
                put(".calx", "application/");
                put(".cat", "application/");
                put(".cc", "text/plain");
                put(".cd", "text/plain");
                put(".cdda", "audio/aiff");
                put(".cdf", "application/x-cdf");
                put(".cer", "application/x-x509-ca-cert");
                put(".chm", "application/octet-stream");
                put(".class", "application/x-java-applet");
                put(".clp", "application/x-msclip");
                put(".cmx", "image/x-cmx");
                put(".cnf", "text/plain");
                put(".cod", "image/cis-cod");
                put(".config", "application/xml");
                put(".contact", "text/x-ms-contact");
                put(".coverage", "application/xml");
                put(".cpio", "application/x-cpio");
                put(".cpp", "text/plain");
                put(".crd", "application/x-mscardfile");
                put(".crl", "application/pkix-crl");
                put(".crt", "application/x-x509-ca-cert");
                put(".cs", "text/plain");
                put(".csdproj", "text/plain");
                put(".csh", "application/x-csh");
                put(".csproj", "text/plain");
                put(".css", "text/css");
                put(".csv", "text/csv");
                put(".cur", "application/octet-stream");
                put(".cxx", "text/plain");
                put(".dat", "application/octet-stream");
                put(".datasource", "application/xml");
                put(".dbproj", "text/plain");
                put(".dcr", "application/x-director");
                put(".def", "text/plain");
                put(".deploy", "application/octet-stream");
                put(".der", "application/x-x509-ca-cert");
                put(".dgml", "application/xml");
                put(".dib", "image/bmp");
                put(".dif", "video/x-dv");
                put(".dir", "application/x-director");
                put(".disco", "text/xml");
                put(".dll", "application/x-msdownload");
                put(".dll.config", "text/xml");
                put(".dlm", "text/dlm");
                put(".doc", "application/msword");
                put(".docm", "application/");
                put(".docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document");
                put(".dot", "application/msword");
                put(".dotm", "application/");
                put(".dotx", "application/vnd.openxmlformats-officedocument.wordprocessingml.template");
                put(".dsp", "application/octet-stream");
                put(".dsw", "text/plain");
                put(".dtd", "text/xml");
                put(".dtsConfig", "text/xml");
                put(".dv", "video/x-dv");
                put(".dvi", "application/x-dvi");
                put(".dwf", "drawing/x-dwf");
                put(".dwp", "application/octet-stream");
                put(".dxr", "application/x-director");
                put(".eml", "message/rfc822");
                put(".emz", "application/octet-stream");
                put(".eot", "application/octet-stream");
                put(".eps", "application/postscript");
                put(".etl", "application/etl");
                put(".etx", "text/x-setext");
                put(".evy", "application/envoy");
                put(".exe", "application/octet-stream");
                put(".exe.config", "text/xml");
                put(".fdf", "application/vnd.fdf");
                put(".fif", "application/fractals");
                put(".filters", "Application/xml");
                put(".fla", "application/octet-stream");
                put(".flr", "x-world/x-vrml");
                put(".flv", "video/x-flv");
                put(".fsscript", "application/fsharp-script");
                put(".fsx", "application/fsharp-script");
                put(".generictest", "application/xml");
                put(".gif", "image/gif");
                put(".group", "text/x-ms-group");
                put(".gsm", "audio/x-gsm");
                put(".gtar", "application/x-gtar");
                put(".gz", "application/x-gzip");
                put(".h", "text/plain");
                put(".hdf", "application/x-hdf");
                put(".hdml", "text/x-hdml");
                put(".hhc", "application/x-oleobject");
                put(".hhk", "application/octet-stream");
                put(".hhp", "application/octet-stream");
                put(".hlp", "application/winhlp");
                put(".hpp", "text/plain");
                put(".hqx", "application/mac-binhex40");
                put(".hta", "application/hta");
                put(".htc", "text/x-component");
                put(".htm", "text/html");
                put(".html", "text/html");
                put(".htt", "text/webviewhtml");
                put(".hxa", "application/xml");
                put(".hxc", "application/xml");
                put(".hxd", "application/octet-stream");
                put(".hxe", "application/xml");
                put(".hxf", "application/xml");
                put(".hxh", "application/octet-stream");
                put(".hxi", "application/octet-stream");
                put(".hxk", "application/xml");
                put(".hxq", "application/octet-stream");
                put(".hxr", "application/octet-stream");
                put(".hxs", "application/octet-stream");
                put(".hxt", "text/html");
                put(".hxv", "application/xml");
                put(".hxw", "application/octet-stream");
                put(".hxx", "text/plain");
                put(".i", "text/plain");
                put(".ico", "image/x-icon");
                put(".ics", "application/octet-stream");
                put(".idl", "text/plain");
                put(".ief", "image/ief");
                put(".iii", "application/x-iphone");
                put(".inc", "text/plain");
                put(".inf", "application/octet-stream");
                put(".inl", "text/plain");
                put(".ins", "application/x-internet-signup");
                put(".ipa", "application/x-itunes-ipa");
                put(".ipg", "application/x-itunes-ipg");
                put(".ipproj", "text/plain");
                put(".ipsw", "application/x-itunes-ipsw");
                put(".iqy", "text/x-ms-iqy");
                put(".isp", "application/x-internet-signup");
                put(".ite", "application/x-itunes-ite");
                put(".itlp", "application/x-itunes-itlp");
                put(".itms", "application/x-itunes-itms");
                put(".itpc", "application/x-itunes-itpc");
                put(".IVF", "video/x-ivf");
                put(".jar", "application/java-archive");
                put(".java", "application/octet-stream");
                put(".jck", "application/liquidmotion");
                put(".jcz", "application/liquidmotion");
                put(".jfif", "image/pjpeg");
                put(".jnlp", "application/x-java-jnlp-file");
                put(".jpb", "application/octet-stream");
                put(".jpe", "image/jpeg");
                put(".jpeg", "image/jpeg");
                put(".jpg", "image/jpeg");
                put(".js", "application/x-javascript");
                put(".json", "application/json");
                put(".jsx", "text/jscript");
                put(".jsxbin", "text/plain");
                put(".latex", "application/x-latex");
                put(".library-ms", "application/windows-library+xml");
                put(".lit", "application/x-ms-reader");
                put(".loadtest", "application/xml");
                put(".lpk", "application/octet-stream");
                put(".lsf", "video/x-la-asf");
                put(".lst", "text/plain");
                put(".lsx", "video/x-la-asf");
                put(".lzh", "application/octet-stream");
                put(".m13", "application/x-msmediaview");
                put(".m14", "application/x-msmediaview");
                put(".m1v", "video/mpeg");
                put(".m2t", "video/vnd.dlna.mpeg-tts");
                put(".m2ts", "video/vnd.dlna.mpeg-tts");
                put(".m2v", "video/mpeg");
                put(".m3u", "audio/x-mpegurl");
                put(".m3u8", "audio/x-mpegurl");
                put(".m4a", "audio/m4a");
                put(".m4b", "audio/m4b");
                put(".m4p", "audio/m4p");
                put(".m4r", "audio/x-m4r");
                put(".m4v", "video/x-m4v");
                put(".mac", "image/x-macpaint");
                put(".mak", "text/plain");
                put(".man", "application/x-troff-man");
                put(".manifest", "application/x-ms-manifest");
                put(".map", "text/plain");
                put(".master", "application/xml");
                put(".mda", "application/msaccess");
                put(".mdb", "application/x-msaccess");
                put(".mde", "application/msaccess");
                put(".mdp", "application/octet-stream");
                put(".me", "application/x-troff-me");
                put(".mfp", "application/x-shockwave-flash");
                put(".mht", "message/rfc822");
                put(".mhtml", "message/rfc822");
                put(".mid", "audio/mid");
                put(".midi", "audio/mid");
                put(".mix", "application/octet-stream");
                put(".mk", "text/plain");
                put(".mmf", "application/x-smaf");
                put(".mno", "text/xml");
                put(".mny", "application/x-msmoney");
                put(".mod", "video/mpeg");
                put(".mov", "video/quicktime");
                put(".movie", "video/x-sgi-movie");
                put(".mp2", "video/mpeg");
                put(".mp2v", "video/mpeg");
                put(".mp3", "audio/mpeg");
                put(".mp4", "video/mp4");
                put(".mp4v", "video/mp4");
                put(".mpa", "video/mpeg");
                put(".mpe", "video/mpeg");
                put(".mpeg", "video/mpeg");
                put(".mpf", "application/");
                put(".mpg", "video/mpeg");
                put(".mpp", "application/");
                put(".mpv2", "video/mpeg");
                put(".mqv", "video/quicktime");
                put(".ms", "application/x-troff-ms");
                put(".msi", "application/octet-stream");
                put(".mso", "application/octet-stream");
                put(".mts", "video/vnd.dlna.mpeg-tts");
                put(".mtx", "application/xml");
                put(".mvb", "application/x-msmediaview");
                put(".mvc", "application/x-miva-compiled");
                put(".mxp", "application/x-mmxp");
                put(".nc", "application/x-netcdf");
                put(".nsc", "video/x-ms-asf");
                put(".nws", "message/rfc822");
                put(".ocx", "application/octet-stream");
                put(".oda", "application/oda");
                put(".odc", "text/x-ms-odc");
                put(".odh", "text/plain");
                put(".odl", "text/plain");
                put(".odp", "application/vnd.oasis.opendocument.presentation");
                put(".ods", "application/oleobject");
                put(".odt", "application/vnd.oasis.opendocument.text");
                put(".one", "application/onenote");
                put(".onea", "application/onenote");
                put(".onepkg", "application/onenote");
                put(".onetmp", "application/onenote");
                put(".onetoc", "application/onenote");
                put(".onetoc2", "application/onenote");
                put(".orderedtest", "application/xml");
                put(".osdx", "application/opensearchdescription+xml");
                put(".p10", "application/pkcs10");
                put(".p12", "application/x-pkcs12");
                put(".p7b", "application/x-pkcs7-certificates");
                put(".p7c", "application/pkcs7-mime");
                put(".p7m", "application/pkcs7-mime");
                put(".p7r", "application/x-pkcs7-certreqresp");
                put(".p7s", "application/pkcs7-signature");
                put(".pbm", "image/x-portable-bitmap");
                put(".pcast", "application/x-podcast");
                put(".pct", "image/pict");
                put(".pcx", "application/octet-stream");
                put(".pcz", "application/octet-stream");
                put(".pdf", "application/pdf");
                put(".pfb", "application/octet-stream");
                put(".pfm", "application/octet-stream");
                put(".pfx", "application/x-pkcs12");
                put(".pgm", "image/x-portable-graymap");
                put(".pic", "image/pict");
                put(".pict", "image/pict");
                put(".pkgdef", "text/plain");
                put(".pkgundef", "text/plain");
                put(".pko", "application/");
                put(".pls", "audio/scpls");
                put(".pma", "application/x-perfmon");
                put(".pmc", "application/x-perfmon");
                put(".pml", "application/x-perfmon");
                put(".pmr", "application/x-perfmon");
                put(".pmw", "application/x-perfmon");
                put(".png", "image/png");
                put(".pnm", "image/x-portable-anymap");
                put(".pnt", "image/x-macpaint");
                put(".pntg", "image/x-macpaint");
                put(".pnz", "image/png");
                put(".pot", "application/");
                put(".potm", "application/");
                put(".potx", "application/vnd.openxmlformats-officedocument.presentationml.template");
                put(".ppa", "application/");
                put(".ppam", "application/");
                put(".ppm", "image/x-portable-pixmap");
                put(".pps", "application/");
                put(".ppsm", "application/");
                put(".ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow");
                put(".ppt", "application/");
                put(".pptm", "application/");
                put(".pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation");
                put(".prf", "application/pics-rules");
                put(".prm", "application/octet-stream");
                put(".prx", "application/octet-stream");
                put(".ps", "application/postscript");
                put(".psc1", "application/PowerShell");
                put(".psd", "application/octet-stream");
                put(".psess", "application/xml");
                put(".psm", "application/octet-stream");
                put(".psp", "application/octet-stream");
                put(".pub", "application/x-mspublisher");
                put(".pwz", "application/");
                put(".qht", "text/x-html-insertion");
                put(".qhtm", "text/x-html-insertion");
                put(".qt", "video/quicktime");
                put(".qti", "image/x-quicktime");
                put(".qtif", "image/x-quicktime");
                put(".qtl", "application/x-quicktimeplayer");
                put(".qxd", "application/octet-stream");
                put(".ra", "audio/x-pn-realaudio");
                put(".ram", "audio/x-pn-realaudio");
                put(".rar", "application/octet-stream");
                put(".ras", "image/x-cmu-raster");
                put(".rat", "application/rat-file");
                put(".rc", "text/plain");
                put(".rc2", "text/plain");
                put(".rct", "text/plain");
                put(".rdlc", "application/xml");
                put(".resx", "application/xml");
                put(".rf", "image/vnd.rn-realflash");
                put(".rgb", "image/x-rgb");
                put(".rgs", "text/plain");
                put(".rm", "application/vnd.rn-realmedia");
                put(".rmi", "audio/mid");
                put(".rmp", "application/vnd.rn-rn_music_package");
                put(".roff", "application/x-troff");
                put(".rpm", "audio/x-pn-realaudio-plugin");
                put(".rqy", "text/x-ms-rqy");
                put(".rtf", "application/rtf");
                put(".rtx", "text/richtext");
                put(".ruleset", "application/xml");
                put(".s", "text/plain");
                put(".safariextz", "application/x-safari-safariextz");
                put(".scd", "application/x-msschedule");
                put(".sct", "text/scriptlet");
                put(".sd2", "audio/x-sd2");
                put(".sdp", "application/sdp");
                put(".sea", "application/octet-stream");
                put(".searchConnector-ms", "application/windows-search-connector+xml");
                put(".setpay", "application/set-payment-initiation");
                put(".setreg", "application/set-registration-initiation");
                put(".settings", "application/xml");
                put(".sgimb", "application/x-sgimb");
                put(".sgml", "text/sgml");
                put(".sh", "application/x-sh");
                put(".shar", "application/x-shar");
                put(".shtml", "text/html");
                put(".sit", "application/x-stuffit");
                put(".sitemap", "application/xml");
                put(".skin", "application/xml");
                put(".sldm", "application/");
                put(".sldx", "application/vnd.openxmlformats-officedocument.presentationml.slide");
                put(".slk", "application/");
                put(".sln", "text/plain");
                put(".slupkg-ms", "application/x-ms-license");
                put(".smd", "audio/x-smd");
                put(".smi", "application/octet-stream");
                put(".smx", "audio/x-smd");
                put(".smz", "audio/x-smd");
                put(".snd", "audio/basic");
                put(".snippet", "application/xml");
                put(".snp", "application/octet-stream");
                put(".sol", "text/plain");
                put(".sor", "text/plain");
                put(".spc", "application/x-pkcs7-certificates");
                put(".spl", "application/futuresplash");
                put(".src", "application/x-wais-source");
                put(".srf", "text/plain");
                put(".SSISDeploymentManifest", "text/xml");
                put(".ssm", "application/streamingmedia");
                put(".sst", "application/");
                put(".stl", "application/");
                put(".sv4cpio", "application/x-sv4cpio");
                put(".sv4crc", "application/x-sv4crc");
                put(".svc", "application/xml");
                put(".swf", "application/x-shockwave-flash");
                put(".t", "application/x-troff");
                put(".tar", "application/x-tar");
                put(".tcl", "application/x-tcl");
                put(".testrunconfig", "application/xml");
                put(".testsettings", "application/xml");
                put(".tex", "application/x-tex");
                put(".texi", "application/x-texinfo");
                put(".texinfo", "application/x-texinfo");
                put(".tgz", "application/x-compressed");
                put(".thmx", "application/");
                put(".thn", "application/octet-stream");
                put(".tif", "image/tiff");
                put(".tiff", "image/tiff");
                put(".tlh", "text/plain");
                put(".tli", "text/plain");
                put(".toc", "application/octet-stream");
                put(".tr", "application/x-troff");
                put(".trm", "application/x-msterminal");
                put(".trx", "application/xml");
                put(".ts", "video/vnd.dlna.mpeg-tts");
                put(".tsv", "text/tab-separated-values");
                put(".ttf", "application/octet-stream");
                put(".tts", "video/vnd.dlna.mpeg-tts");
                put(".txt", "text/plain");
                put(".u32", "application/octet-stream");
                put(".uls", "text/iuls");
                put(".user", "text/plain");
                put(".ustar", "application/x-ustar");
                put(".vb", "text/plain");
                put(".vbdproj", "text/plain");
                put(".vbk", "video/mpeg");
                put(".vbproj", "text/plain");
                put(".vbs", "text/vbscript");
                put(".vcf", "text/x-vcard");
                put(".vcproj", "Application/xml");
                put(".vcs", "text/plain");
                put(".vcxproj", "Application/xml");
                put(".vddproj", "text/plain");
                put(".vdp", "text/plain");
                put(".vdproj", "text/plain");
                put(".vdx", "application/");
                put(".vml", "text/xml");
                put(".vscontent", "application/xml");
                put(".vsct", "text/xml");
                put(".vsd", "application/vnd.visio");
                put(".vsi", "application/ms-vsi");
                put(".vsix", "application/vsix");
                put(".vsixlangpack", "text/xml");
                put(".vsixmanifest", "text/xml");
                put(".vsmdi", "application/xml");
                put(".vspscc", "text/plain");
                put(".vss", "application/vnd.visio");
                put(".vsscc", "text/plain");
                put(".vssettings", "text/xml");
                put(".vssscc", "text/plain");
                put(".vst", "application/vnd.visio");
                put(".vstemplate", "text/xml");
                put(".vsto", "application/x-ms-vsto");
                put(".vsw", "application/vnd.visio");
                put(".vsx", "application/vnd.visio");
                put(".vtx", "application/vnd.visio");
                put(".wav", "audio/wav");
                put(".wave", "audio/wav");
                put(".wax", "audio/x-ms-wax");
                put(".wbk", "application/msword");
                put(".wbmp", "image/vnd.wap.wbmp");
                put(".wcm", "application/");
                put(".wdb", "application/");
                put(".wdp", "image/");
                put(".webarchive", "application/x-safari-webarchive");
                put(".webtest", "application/xml");
                put(".wiq", "application/xml");
                put(".wiz", "application/msword");
                put(".wks", "application/");
                put(".WLMP", "application/wlmoviemaker");
                put(".wlpginstall", "application/x-wlpg-detect");
                put(".wlpginstall3", "application/x-wlpg3-detect");
                put(".wm", "video/x-ms-wm");
                put(".wma", "audio/x-ms-wma");
                put(".wmd", "application/x-ms-wmd");
                put(".wmf", "application/x-msmetafile");
                put(".wml", "text/vnd.wap.wml");
                put(".wmlc", "application/vnd.wap.wmlc");
                put(".wmls", "text/vnd.wap.wmlscript");
                put(".wmlsc", "application/vnd.wap.wmlscriptc");
                put(".wmp", "video/x-ms-wmp");
                put(".wmv", "video/x-ms-wmv");
                put(".wmx", "video/x-ms-wmx");
                put(".wmz", "application/x-ms-wmz");
                put(".wpl", "application/");
                put(".wps", "application/");
                put(".wri", "application/x-mswrite");
                put(".wrl", "x-world/x-vrml");
                put(".wrz", "x-world/x-vrml");
                put(".wsc", "text/scriptlet");
                put(".wsdl", "text/xml");
                put(".wvx", "video/x-ms-wvx");
                put(".x", "application/directx");
                put(".xaf", "x-world/x-vrml");
                put(".xaml", "application/xaml+xml");
                put(".xap", "application/x-silverlight-app");
                put(".xbap", "application/x-ms-xbap");
                put(".xbm", "image/x-xbitmap");
                put(".xdr", "text/plain");
                put(".xht", "application/xhtml+xml");
                put(".xhtml", "application/xhtml+xml");
                put(".xla", "application/");
                put(".xlam", "application/");
                put(".xlc", "application/");
                put(".xld", "application/");
                put(".xlk", "application/");
                put(".xll", "application/");
                put(".xlm", "application/");
                put(".xls", "application/");
                put(".xlsb", "application/");
                put(".xlsm", "application/");
                put(".xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
                put(".xlt", "application/");
                put(".xltm", "application/");
                put(".xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template");
                put(".xlw", "application/");
                put(".xml", "text/xml");
                put(".xmta", "application/xml");
                put(".xof", "x-world/x-vrml");
                put(".XOML", "text/plain");
                put(".xpm", "image/x-xpixmap");
                put(".xps", "application/");
                put(".xrm-ms", "text/xml");
                put(".xsc", "application/xml");
                put(".xsd", "text/xml");
                put(".xsf", "text/xml");
                put(".xsl", "text/xml");
                put(".xslt", "text/xml");
                put(".xsn", "application/octet-stream");
                put(".xss", "application/xml");
                put(".xtp", "application/octet-stream");
                put(".xwd", "image/x-xwindowdump");
                put(".z", "application/x-compress");
                put(".zip", "application/x-zip-compressed");

    public static String getMimeType(String extension) {
        if (extension == null) {
            return null;

        if (!extension.startsWith(".")) {
            extension = "." + extension.toLowerCase(Locale.getDefault());

        String mime = mimeTypes.get(extension);

        return mime != null ? mime : "application/octet-stream";

How to erase the file contents of text file in Python?

In python:

open('file.txt', 'w').close()

Or alternatively, if you have already an opened file:

f = open('file.txt', 'r+')
f.truncate(0) # need '0' when using r+

In C++, you could use something similar.

How to get full file path from file name?



Install .ipa to iPad with or without iTunes

You can also checkout ios-deploy.

It is as simple as running ios-deploy -b path/to/ipa/file.

It even works with path/to/, which should be in the same location if you are doing cordova/phonegap builds locally.


Android AudioRecord example

Here I am posting you the some code example which record good quality of sound using AudioRecord API.

Note: If you use in emulator the sound quality will not much good because we are using sample rate 8k which only supports in emulator. In device use sample rate to 44.1k for better quality.

public class Audio_Record extends Activity {
    private static final int RECORDER_SAMPLERATE = 8000;
    private static final int RECORDER_CHANNELS = AudioFormat.CHANNEL_IN_MONO;
    private static final int RECORDER_AUDIO_ENCODING = AudioFormat.ENCODING_PCM_16BIT;
    private AudioRecord recorder = null;
    private Thread recordingThread = null;
    private boolean isRecording = false;

    public void onCreate(Bundle savedInstanceState) {


        int bufferSize = AudioRecord.getMinBufferSize(RECORDER_SAMPLERATE,

    private void setButtonHandlers() {
        ((Button) findViewById(;
        ((Button) findViewById(;

    private void enableButton(int id, boolean isEnable) {
        ((Button) findViewById(id)).setEnabled(isEnable);

    private void enableButtons(boolean isRecording) {
        enableButton(, !isRecording);
        enableButton(, isRecording);

    int BufferElements2Rec = 1024; // want to play 2048 (2K) since 2 bytes we use only 1024
    int BytesPerElement = 2; // 2 bytes in 16bit format

    private void startRecording() {

        recorder = new AudioRecord(MediaRecorder.AudioSource.MIC,
                RECORDER_AUDIO_ENCODING, BufferElements2Rec * BytesPerElement);

        isRecording = true;
        recordingThread = new Thread(new Runnable() {
            public void run() {
        }, "AudioRecorder Thread");

        //convert short to byte
    private byte[] short2byte(short[] sData) {
        int shortArrsize = sData.length;
        byte[] bytes = new byte[shortArrsize * 2];
        for (int i = 0; i < shortArrsize; i++) {
            bytes[i * 2] = (byte) (sData[i] & 0x00FF);
            bytes[(i * 2) + 1] = (byte) (sData[i] >> 8);
            sData[i] = 0;
        return bytes;


    private void writeAudioDataToFile() {
        // Write the output audio in byte

        String filePath = "/sdcard/voice8K16bitmono.pcm";
        short sData[] = new short[BufferElements2Rec];

        FileOutputStream os = null;
        try {
            os = new FileOutputStream(filePath);
        } catch (FileNotFoundException e) {

        while (isRecording) {
            // gets the voice output from microphone to byte format

  , 0, BufferElements2Rec);
            System.out.println("Short writing to file" + sData.toString());
            try {
                // // writes the data to file from buffer
                // // stores the voice buffer
                byte bData[] = short2byte(sData);
                os.write(bData, 0, BufferElements2Rec * BytesPerElement);
            } catch (IOException e) {
        try {
        } catch (IOException e) {

    private void stopRecording() {
        // stops the recording activity
        if (null != recorder) {
            isRecording = false;
            recorder = null;
            recordingThread = null;

    private View.OnClickListener btnClick = new View.OnClickListener() {
        public void onClick(View v) {
            switch (v.getId()) {
            case {
            case {

    public boolean onKeyDown(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_BACK) {
        return super.onKeyDown(keyCode, event);

For more detail try this AUDIORECORD BLOG.

Happy Coding !!

Scroll Automatically to the Bottom of the Page

If you want to scroll entire page to the bottom:

var scrollingElement = (document.scrollingElement || document.body);
scrollingElement.scrollTop = scrollingElement.scrollHeight;

See the sample on JSFiddle

If you want to scroll an element to the bottom:

function gotoBottom(id){
   var element = document.getElementById(id);
   element.scrollTop = element.scrollHeight - element.clientHeight;

And that's how it works:

enter image description here

Ref: scrollTop, scrollHeight, clientHeight

UPDATE: Latest versions of Chrome (61+) and Firefox does not support scrolling of body, see:

How to set cell spacing and UICollectionView - UICollectionViewFlowLayout size ratio?

Add these 2 lines

layout.minimumInteritemSpacing = 0
layout.minimumLineSpacing = 0

So you have:

   // Do any additional setup after loading the view, typically from a nib.
        let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()
        layout.sectionInset = UIEdgeInsets(top: 20, left: 0, bottom: 10, right: 0)
        layout.itemSize = CGSize(width: screenWidth/3, height: screenWidth/3)
        layout.minimumInteritemSpacing = 0
        layout.minimumLineSpacing = 0
        collectionView!.collectionViewLayout = layout

That will remove all the spaces and give you a grid layout:

enter image description here

If you want the first column to have a width equal to the screen width then add the following function:

func collectionView(collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAtIndexPath indexPath: NSIndexPath) -> CGSize {
    if indexPath.row == 0
        return CGSize(width: screenWidth, height: screenWidth/3)
    return CGSize(width: screenWidth/3, height: screenWidth/3);


Grid layout will now look like (I've also added a blue background to first cell): enter image description here

Index of element in NumPy array

This problem can be solved efficiently using the numpy_indexed library (disclaimer: I am its author); which was created to address problems of this type. npi.indices can be viewed as an n-dimensional generalisation of list.index. It will act on nd-arrays (along a specified axis); and also will look up multiple entries in a vectorized manner as opposed to a single item at a time.

a = np.random.rand(50, 60, 70)
i = np.random.randint(0, len(a), 40)
b = a[i]

import numpy_indexed as npi
assert all(i == npi.indices(a, b))

This solution has better time complexity (n log n at worst) than any of the previously posted answers, and is fully vectorized.

HTML email in outlook table width issue - content is wider than the specified table width

I guess problem is in width attributes in table and td remove 'px' for example

<table border="0" cellpadding="0" cellspacing="0" width="580px" style="background-color: #0290ba;">

Should be

<table border="0" cellpadding="0" cellspacing="0" width="580" style="background-color: #0290ba;">

How can I get my webapp's base URL in ASP.NET MVC?

This is a conversion of an property to MVC . It's a pretty much all singing all dancing get root url method.

Declare a helper class:

namespace MyTestProject.Helpers
    using System.Web;

    public static class PathHelper
        public static string FullyQualifiedApplicationPath(HttpRequestBase httpRequestBase)
            string appPath = string.Empty;

            if (httpRequestBase != null)
                //Formatting the fully qualified website url/name
                appPath = string.Format("{0}://{1}{2}{3}",
                            httpRequestBase.Url.Port == 80 ? string.Empty : ":" + httpRequestBase.Url.Port,

            if (!appPath.EndsWith("/"))
                appPath += "/";

            return appPath;


To use from a controller:


To use in a view:

@using MyTestProject.Helpers


How to set ID using javascript?

Do you mean like this?

var hello1 = document.getElementById('hello1'); = btoa(;

To further the example, say you wanted to get all elements with the class 'abc'. We can use querySelectorAll() to accomplish this:


<div class="abc"></div>
<div class="abc"></div>


var abcElements = document.querySelectorAll('.abc');

// Set their ids
for (var i = 0; i < abcElements.length; i++)
    abcElements[i].id = 'abc-' + i;

This will assign the ID 'abc-<index number>' to each element. So it would come out like this:

<div class="abc" id="abc-0"></div>
<div class="abc" id="abc-1"></div>

To create an element and assign an id we can use document.createElement() and then appendChild().

var div = document.createElement('div'); = 'hello1';

var body = document.querySelector('body');


You can set the id on your element like this if your script is in your HTML file.

<input id="{{str(product["avt"]["fto"])}}" >
<span>New price :</span>
<span class="assign-me">

<script type="text/javascript">
    var s = document.getElementsByClassName('assign-me')[0]; = btoa({{str(produit["avt"]["fto"])}});

Your requirements still aren't 100% clear though.

How to get CRON to call in the correct PATHs

The simplest workaround I've found looks like this:

* * * * * root su -l -c command

This example invokes su as root user and starts the shell with the user's full environment, including $PATH, set as if they were logged in. It works the same on different distros, is more reliable than sourcing .bashrc (which hasn't worked for me) and avoids hardcoding specific paths which can be a problem if you're providing an example or setup tool and don't know what distro or file layout on the user's system.

You can also specify the username after su if you want a different user than root, but you should probably leave the root parameter before su command since this ensures su has sufficient privileges to switch to any user you specify.

What is the { get; set; } syntax in C#?

A property is a like a layer that separates the private variable from other members of a class. From outside world it feels like a property is just a field, a property can be accessed using .Property

public class Person
    public string FirstName { get; set; }

    public string LastName { get; set; }

    public string FullName => $"{FirstName} {LastName}";

public class Person
    public string FirstName { get; set; }

    public string LastName { get; set; }

    public string FullName { get { return $"{FirstName} {LastName}"; } }

FullName is a Property. The one with arrow is a shortcut. From outside world, we can access FullName like this:

var person = new Person();

Callers do not care about how you implemented the FullName. But inside the class you can change FullName whatever you want.

Check out Microsoft Documentation for more detailed explanation:

Set HTML dropdown selected option using JSTL

Assuming that you have a collection ${roles} of the elements to put in the combo, and ${selected} the selected element, It would go like this:

<select name='role'>
    <option value="${selected}" selected>${selected}</option>
    <c:forEach items="${roles}" var="role">
        <c:if test="${role != selected}">
            <option value="${role}">${role}</option>

UPDATE (next question)

You are overwriting the attribute "productSubCategoryName". At the end of the for loop, the last productSubCategoryName.

Because of the limitations of the expression language, I think the best way to deal with this is to use a map:

Map<String,Boolean> map = new HashMap<String,Boolean>();
for(int i=0;i<userProductData.size();i++){
    String productSubCategoryName=userProductData.get(i).getProductSubCategory();
    map.put(productSubCategoryName, true);
request.setAttribute("productSubCategoryMap", map);

And then in the JSP:

<select multiple="multiple" name="prodSKUs">
    <c:forEach items="${productSubCategoryList}" var="productSubCategoryList">
        <option value="${productSubCategoryList}" ${not empty productSubCategoryMap[productSubCategoryList] ? 'selected' : ''}>${productSubCategoryList}</option>

UILabel - auto-size label to fit text?

  1. Add missing constraints in storyboard.
  2. Select UILabel in storyboard and set the attributes "Line" to 0.
  3. Ref Outlet the UILabel to Controller.h with id:label
  4. Controller.m and add [label sizeToFit]; in viewDidLoad

"application blocked by security settings" prevent applets running using oracle SE 7 update 51 on firefox on Linux mint

You can also use Edit Site List and make it be an exception so that you can run it from the specific website.

Regular expression for validating names and surnames?

This one worked perfectly for me in JavaScript: ^[a-zA-Z]+[\s|-]?[a-zA-Z]+[\s|-]?[a-zA-Z]+$

Here is the method:

function isValidName(name) {
    var found =^[a-zA-Z]+[\s|-]?[a-zA-Z]+[\s|-]?[a-zA-Z]+$/);
    return found > -1;

Create a circular button in BS3

To add a rounded border in any button the best way is to add the border-radius property. I belive this class is better because you can add-it at any button size. If you set the height and widht you will need to create a "rouding" class to each button size.

.btn-circle {_x000D_
  border-radius: 50%;_x000D_
<button class='btn-circle'>Click Me!</button>_x000D_
<button class='btn-circle'>?</button>

Find IP address of directly connected device

You can also get information from directly connected networking devices, such as network switches with LDWin, a portable and free Windows program published on github:

LDWin supports the following methods of link discovery: CDP (Cisco Discovery Protocol) and LLDP (Link Layer Discovery Protocol).

You can obtain the model, management IP, VLAN identifier, Port identifier, firmware version, etc.

JTable How to refresh table model after insert delete or update the data.

If you want to notify your JTable about changes of your data, use

From the documentation:

Notifies all listeners that all cell values in the table's rows may have changed. The number of rows may also have changed and the JTable should redraw the table from scratch. The structure of the table (as in the order of the columns) is assumed to be the same.

How to implement a queue using two stacks?

Below is the solution in javascript language using ES6 syntax.


//stack using array
class Stack {
  constructor() { = [];

  push(data) {;

  pop() {

  peek() {
    return[ - 1];


export { Stack };


import { Stack } from "./Stack";

class QueueUsingTwoStacks {
  constructor() {
    this.stack1 = new Stack();
    this.stack2 = new Stack();

  enqueue(data) {

  dequeue() {
    //if both stacks are empty, return undefined
    if (this.stack1.size() === 0 && this.stack2.size() === 0)
      return undefined;

    //if stack2 is empty, pop all elements from stack1 to stack2 till stack1 is empty
    if (this.stack2.size() === 0) {
      while (this.stack1.size() !== 0) {

    //pop and return the element from stack 2
    return this.stack2.pop();

export { QueueUsingTwoStacks };

Below is the usage:


import { StackUsingTwoQueues } from './StackUsingTwoQueues';

let que = new QueueUsingTwoStacks();

console.log(que.dequeue());  //output: "A"

Model summary in pytorch

Keras like model summary using torchsummary:

from torchsummary import summary
summary(model, input_size=(3, 224, 224))

PHP Converting Integer to Date, reverse of strtotime

Yes you can convert it back. You can try:

date("Y-m-d H:i:s", 1388516401);

The logic behind this conversion from date to an integer is explained in strtotime in PHP:

The function expects to be given a string containing an English date format and will try to parse that format into a Unix timestamp (the number of seconds since January 1 1970 00:00:00 UTC), relative to the timestamp given in now, or the current time if now is not supplied.

For example, strtotime("1970-01-01 00:00:00") gives you 0 and strtotime("1970-01-01 00:00:01") gives you 1.

This means that if you are printing strtotime("2014-01-01 00:00:01") which will give you output 1388516401, so the date 2014-01-01 00:00:01 is 1,388,516,401 seconds after January 1 1970 00:00:00 UTC.

Unfortunately Launcher3 has stopped working error in android studio?

It appears to be relate to the graphics driver. In the emulator configuration, changing Emulated Graphics to Software - GLES 2.0 caused the crashes to stop.

jQuery selector for id starts with specific text

If all your divs start with editDialog as you stated, then you can use the following selector:


Or you could use a class selector instead if it's easier for you

<div id="editDialog-0" class="editDialog">...</div>


For loop example in MySQL

drop table if exists foo;
create table foo
id int unsigned not null auto_increment primary key,
val smallint unsigned not null default 0

drop procedure if exists load_foo_test_data;

delimiter #
create procedure load_foo_test_data()

declare v_max int unsigned default 1000;
declare v_counter int unsigned default 0;

  truncate table foo;
  start transaction;
  while v_counter < v_max do
    insert into foo (val) values ( floor(0 + (rand() * 65535)) );
    set v_counter=v_counter+1;
  end while;
end #

delimiter ;

call load_foo_test_data();

select * from foo order by id;

How to send JSON instead of a query string with $.ajax?

If you are sending this back to and need the data in request.form[] then you'll need to set the content type to "application/x-www-form-urlencoded; charset=utf-8"

Original post here

Secondly get rid of the Datatype, if your not expecting a return the POST will wait for about 4 minutes before failing. See here

Regular Expression: Allow letters, numbers, and spaces (with at least one letter or number)

To go ahead and get a point out there, instead of repeatedly using these:

[A-Za-z0-9 _]

I have two (hopefully better) replacements for those two:

[\w ]

The first one matches any word character (alphanumeric and _, as well as Unicode) and the space. The second matches anything that isn't a non-word character or an underscore (alphanumeric only, as well as Unicode).

If you don't want Unicode matching, then stick with the other answers. But these just look easier on the eyes (in my opinion). Taking the "preferred" answer as of this writing and using the shorter regexes gives us:

^[\w ]*[^\W_][\w ]*$

Perhaps more readable, perhaps less. Certainly shorter. Your choice.


Just as a note, I am assuming Perl-style regexes here. Your regex engine may or may not support things like \w and \W.


Tested mine with the JS regex tester that someone linked to and some basic examples worked fine. Didn't do anything extensive, just wanted to make sure that \w and \W worked fine in JS.


Having tried to test some Unicode with the JS regex tester site, I've discovered the problem: that page uses ISO instead of Unicode. No wonder my Japanese input didn't match. Oh well, that shouldn't be difficult to fix:

<meta http-equiv="Content-Type" content="text/html; charset=utf-8">

Or so. I don't know what should be done as far as JavaScript, but I'm sure it's not hard.

How to implement DrawerArrowToggle from Android appcompat v7 21 library

To answer the updated part of your question: to style the drawer icon/arrow, you have two options:

Style the arrow itself

To do this, override drawerArrowStyle in your theme like so:

<style name="AppBaseTheme" parent="Theme.AppCompat.Light">
    <item name="drawerArrowStyle">@style/MyTheme.DrawerArrowToggle</item>
<style name="MyTheme.DrawerArrowToggle" parent="Widget.AppCompat.DrawerArrowToggle">
    <item name="color">@android:color/holo_purple</item>
    <!-- ^ this will make the icon purple -->

This is probably not what you want, because the ActionBar itself should have consistent styling with the arrow, so, most probably, you want the option two:

Theme the ActionBar/Toolbar

Override the android:actionBarTheme (actionBarTheme for appcompat) attribute of the global application theme with your own theme (which you probably should derive from ThemeOverlay.Material.ActionBar/ThemeOverlay.AppCompat.ActionBar) like so:

<style name="AppBaseTheme" parent="Theme.AppCompat.Light">
    <item name="actionBarTheme">@style/MyTheme.ActionBar</item>
<style name="MyTheme.ActionBar" parent="ThemeOverlay.AppCompat.ActionBar">
    <item name="android:textColorPrimary">@android:color/white</item>
    <!-- ^ this will make text and arrow white -->
    <!-- you can also override drawerArrowStyle here -->

An important note here is that when using a custom layout with a Toolbar instead of stock ActionBar implementation (e.g. if you're using the DrawerLayout-NavigationView-Toolbar combo to achieve the Material-style drawer effect where it's visible under translucent statusbar), the actionBarTheme attribute is obviosly not picked up automatically (because it's meant to be taken care of by the AppCompatActivity for the default ActionBar), so for your custom Toolbar don't forget to apply your theme manually:

<!--inside your custom layout with DrawerLayout
and NavigationView or whatever -->

-- this will resolve to either AppCompat's default ThemeOverlay.AppCompat.ActionBar or your override if you set the attribute in your derived theme.

PS a little comment about the drawerArrowStyle override and the spinBars attribute -- which a lot of sources suggest should be set to true to get the drawer/arrow animation. Thing is, spinBars it is true by default in AppCompat (check out the Base.Widget.AppCompat.DrawerArrowToggle.Common style), you don't have to override actionBarTheme at all to get the animation working. You get the animation even if you do override it and set the attribute to false, it's just a different, less twirly animation. The important thing here is to use ActionBarDrawerToggle, it's what pulls in the fancy animated drawable.

Add back button to action bar

Simpler and better: For API >= 16

Simply add "parentActivityName" for each activity in Manifest. The back button will automatically take u to the parent activity.

        android:parentActivityName="com.example.myfirstapp.MainActivity" >

How do I make an auto increment integer field in Django?

You can create an autofield. Here is the documentation for the same

Please remember Django won't allow to have more than one AutoField in a model, In your model you already have one for your primary key (which is default). So you'll have to override model's save method and will probably fetch the last inserted record from the table and accordingly increment the counter and add the new record.

Please make that code thread safe because in case of multiple requests you might end up trying to insert same value for different new records.

SQL JOIN - WHERE clause vs. ON clause

Let's consider those tables :


id | SomeData


id | id_A | SomeOtherData

id_A being a foreign key to table A

Writting this query :

ON = B.id_A;

Will provide this result :

/ : part of the result
            A         |                                 |
+---------------------+-------+                         |
|/////////////////////|///////|                         |
|/////////////////////|///////|                         |
|/////////////////////|///////|                         |
|/////////////////////|///////|                         |

What is in A but not in B means that there is null values for B.

Now, let's consider a specific part in B.id_A, and highlight it from the previous result :

/ : part of the result
* : part of the result with the specific B.id_A
            A         |                                 |
+---------------------+-------+                         |
|/////////////////////|///////|                         |
|/////////////////////|///////|                         |
|/////////////////////+---+///|                         |
|/////////////////////|***|///|                         |

Writting this query :

ON = B.id_A
AND B.id_A = SpecificPart;

Will provide this result :

/ : part of the result
* : part of the result with the specific B.id_A
            A         |                                 |
+---------------------+-------+                         |
|/////////////////////|       |                         |
|/////////////////////|       |                         |
|/////////////////////+---+   |                         |
|/////////////////////|***|   |                         |

Because this removes in the inner join the values that aren't in B.id_A = SpecificPart

Now, let's change the query to this :

ON = B.id_A
WHERE B.id_A = SpecificPart;

The result is now :

/ : part of the result
* : part of the result with the specific B.id_A
            A         |                                 |
+---------------------+-------+                         |
|                     |       |                         |
|                     |       |                         |
|                     +---+   |                         |
|                     |***|   |                         |
|                     +---+---+-------------------------+
|                             |

Because the whole result is filtered against B.id_A = SpecificPart removing the parts B.id_A IS NULL, that are in the A that aren't in B

ALTER TABLE DROP COLUMN failed because one or more objects access this column

In addition to accepted answer, if you're using Entity Migrations for updating database, you should add this line at the beggining of the Up() function in your migration file:

Sql("alter table dbo.CompanyTransactions drop constraint [df__CompanyTr__Creat__0cdae408];");

You can find the constraint name in the error at nuget packet manager console which starts with FK_dbo.

2 "style" inline css img tags?

Do not use more than one style attribute. Just seperate styles in the style attribute with ; It is a block of inline CSS, so think of this as you would do CSS in a separate stylesheet.

So in this case its: style="height:100px;width:100px;"

You can use this for any CSS style, so if you wanted to change the colour of the text to white: style="height:100px;width:100px;color:#ffffff" and so on.

However, it is worth using inline CSS sparingly, as it can make code less manageable in future. Using an external stylesheet may be a better option for this. It depends really on your requirements. Inline CSS does make for quicker coding.

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

For those searching for the inverse of this, i.e. looking for tables that do not contain a certain column name, here is the query...

SELECT DISTINCT TABLE_NAME FROM information_schema.columns WHERE 
TABLE_NAME FROM information_schema.columns WHERE column_name = 
'column_name' AND TABLE_SCHEMA = 'your_db_name');

This came in really handy when we began to slowly implement use of InnoDB's special ai_col column and needed to figure out which of our 200 tables had yet to be upgraded.

How to link 2 cell of excel sheet?

I Found Solution Of You Question But In Stack Not Allow to Upload Video See the link below it show better explain

How to link two (multiple) workbooks and cells in Excel...

To get total number of columns in a table in sql

The below query will display all the tables and corresponding column count in a database schema

SELECT Table_Name, count(*) as [No.of Columns]
WHERE table_schema = 'dbo' -- schema name
group by table_name

Export DataBase with MySQL Workbench with INSERT statements

You can do it using mysqldump tool in command-line:

mysqldump your_database_name > script.sql

This creates a file with database create statements together with insert statements.

More info about options for mysql dump:

How to write MySQL query where A contains ( "a" or "b" )

I've used most of the times the LIKE option and it works just fine. I just like to share one of my latest experiences where I used INSTR function. Regardless of the reasons that made me consider this options, what's important here is that the use is similar: instr(A, 'text 1') > 0 or instr(A, 'text 2') > 0 Another option could be: (instr(A, 'text 1') + instr(A, 'text 2')) > 0

I'd go with the LIKE '%text1%' OR LIKE '%text2%' option... if not hope this other option helps

What 'additional configuration' is necessary to reference a .NET 2.0 mixed mode assembly in a .NET 4.0 project?

This forum post on the .NET Framework Developer Center. It might provide some insight.

(Add to the app's config file.)

  <startup useLegacyV2RuntimeActivationPolicy="true">
    <supportedRuntime version="v4.0"/>

MySQL dump by query

Combining much of above here is my real practical example, selecting records based on both meterid & timestamp. I have needed this command for years. Executes really quickly.

mysqldump -uuser -ppassword main_dbo trHourly --where="MeterID =5406 AND TIMESTAMP<'2014-10-13 05:00:00'" --no-create-info --skip-extended-insert | grep  '^INSERT' > 5406.sql

mysql error 1364 Field doesn't have a default values

Its work and tested Copy to Config File: /etc/mysql/my.cnf OR /bin/mysql/my.ini

port = 3306

then restart MySQL

Add st, nd, rd and th (ordinal) suffix to a number

You've only got 12 days? I'd be tempted to make it just a simple lookup array:

var suffixes = ['','st','nd','rd','th','th','th','th','th','th','th','th','th'];


var i = 2;
var day = i + suffixes[i]; // result: '2nd'


var i = 8;
var day = i + suffixes[i]; // result: '8th'

Get access to parent control from user control - C#

Not Ideal, but try this...

Change the usercontrol to Component class (In the code editor), build the solution and remove all the code with errors (Related to usercontrols but not available in components so the debugger complains about it)

Change the usercontrol back to usercontrol class...

Now it recognises the name and parent property but shows the component as non-visual as it is no longer designable.

Convert JsonNode into POJO

String jsonInput = "{ \"hi\": \"Assume this is the JSON\"} ";
com.fasterxml.jackson.databind.ObjectMapper mapper =
    new com.fasterxml.jackson.databind.ObjectMapper();
MyClass myObject = objectMapper.readValue(jsonInput, MyClass.class);

If your JSON input in has more properties than your POJO has and you just want to ignore the extras in Jackson 2.4, you can configure your ObjectMapper as follows. This syntax is different from older Jackson versions. (If you use the wrong syntax, it will silently do nothing.)


Java multiline string


Java 8 added a new static method to java.lang.String which offers a slightly better alternative:

String.join( CharSequence delimiter , CharSequence... elements )

Using it:

String s = String.join(
    "First line.",
    "Second line.",
    "The rest.",
    "And the last!"

Shell script current directory?

To print the current working Directory i.e. pwd just type command like:

echo "the PWD is : ${pwd}"

Redirecting 404 error with .htaccess via 301 for SEO etc

I came up with the solution and posted it on my blog

here is the htaccess code also

RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule . / [L,R=301]

but I posted other solutions on my blog too, it depends what you need really

Convert JSON string to array of JSON objects in Javascript

If your using jQuery, it's parseJSON function can be used and is preferable to JavaScript's native eval() function.

Make a negative number positive

You want to wrap each number into Math.abs(). e.g.


prints out "1".

If you want to avoid writing the Math.-part, you can include the Math util statically. Just write

import static java.lang.Math.abs;

along with your imports, and you can refer to the abs()-function just by writing


Add single element to array in numpy

append() creates a new array which can be the old array with the appended element.

I think it's more normal to use the proper method for adding an element:

a = numpy.append(a, a[0])

Is List<Dog> a subclass of List<Animal>? Why are Java generics not implicitly polymorphic?

Lets take the example from JavaSE tutorial

public abstract class Shape {
    public abstract void draw(Canvas c);

public class Circle extends Shape {
    private int x, y, radius;
    public void draw(Canvas c) {

public class Rectangle extends Shape {
    private int x, y, width, height;
    public void draw(Canvas c) {

So why a list of dogs (circles) should not be considered implicitly a list of animals (shapes) is because of this situation:

// drawAll method call

public void drawAll(List<Shape> shapes) {
   shapes.add(new Rectangle());    

So Java "architects" had 2 options which address this problem:

  1. do not consider that a subtype is implicitly it's supertype, and give a compile error, like it happens now

  2. consider the subtype to be it's supertype and restrict at compile the "add" method (so in the drawAll method, if a list of circles, subtype of shape, would be passed, the compiler should detected that and restrict you with compile error into doing that).

For obvious reasons, that chose the first way.

DD/MM/YYYY Date format in Moment.js

You can use this


However, this returns a date string in the specified format for today, not a moment date object. Doing the following will make it a moment date object in the format you want.

var someDateString = moment().format("DD/MM/YYYY");
var someDate = moment(someDateString, "DD/MM/YYYY");

Append to string variable

var str1 = 'abc';
var str2 = str1+' def'; // str2 is now 'abc def'

Handling NULL values in Hive

Firstly — I don't think column1 is not NULL or column1 <> '' makes very much sense. Maybe you meant to write column1 is not NULL and column1 <> '' (AND instead of OR)?

Secondly — because of Hive's "schema on read" approach to table definitions, invalid values will be converted to NULL when you read from them. So, for example, if table1.column1 is of type STRING and table2.column1 is of type INT, then I don't think that table1.column1 IS NOT NULL is enough to guarantee that table2.column1 IS NOT NULL. (I'm not sure about this, though.)

How can I create an observable with a delay

import * as Rx from 'rxjs/Rx';

We should add the above import to make the blow code to work

Let obs = Rx.Observable

obs.subscribe(value => console.log('Subscriber: ' + value));

Simple tool to 'accept theirs' or 'accept mine' on a whole file using git

The solution is very simple. git checkout <filename> tries to check out file from the index, and therefore fails on merge.

What you need to do is (i.e. checkout a commit):

To checkout your own version you can use one of:

git checkout HEAD -- <filename>


git checkout --ours -- <filename>

(Warning!: If you are rebasing --ours and --theirs are swapped.)


git show :2:<filename> > <filename> # (stage 2 is ours)

To checkout the other version you can use one of:

git checkout test-branch -- <filename>


git checkout --theirs -- <filename>


git show :3:<filename> > <filename> # (stage 3 is theirs)

You would also need to run 'add' to mark it as resolved:

git add <filename>

Pros/cons of using redux-saga with ES6 generators vs redux-thunk with ES2017 async/await

Update in July 2020:

During the last 16 months, maybe the most notable change in the React community is React hooks.

According to what I observe, in order to gain better compatibility with functional components and hooks, projects (even those large ones) would tend to use:

  1. hook + async thunk (hook makes everything very flexible so you could actually place async thunk in where you want and use it as normal functions, for example, still write thunk in action.ts and then useDispatch() to trigger the thunk:,
  2. useRequest,
  3. GraphQL/Apollo useQuery useMutation
  4. react-fetching-library
  5. other popular choices of data fetching/API call libraries, tools, design patterns, etc

In comparison, redux-saga doesn't really provide significant benefit in most normal cases of API calls comparing to the above approaches for now, while increasing project complexity by introducing many saga files/generators (also because the last release v1.1.1 of redux-saga was on 18 Sep 2019, which was a long time ago).

But still, redux-saga provides some unique features such as racing effect and parallel requests. Therefore, if you need these special functionalities, redux-saga is still a good choice.

Original post in March 2019:

Just some personal experience:

  1. For coding style and readability, one of the most significant advantages of using redux-saga in the past is to avoid callback hell in redux-thunk — one does not need to use many nesting then/catch anymore. But now with the popularity of async/await thunk, one could also write async code in sync style when using redux-thunk, which may be regarded as an improvement in redux-thunk.

  2. One may need to write much more boilerplate codes when using redux-saga, especially in Typescript. For example, if one wants to implement a fetch async function, the data and error handling could be directly performed in one thunk unit in action.js with one single FETCH action. But in redux-saga, one may need to define FETCH_START, FETCH_SUCCESS and FETCH_FAILURE actions and all their related type-checks, because one of the features in redux-saga is to use this kind of rich “token” mechanism to create effects and instruct redux store for easy testing. Of course one could write a saga without using these actions, but that would make it similar to a thunk.

  3. In terms of the file structure, redux-saga seems to be more explicit in many cases. One could easily find an async related code in every sagas.ts, but in redux-thunk, one would need to see it in actions.

  4. Easy testing may be another weighted feature in redux-saga. This is truly convenient. But one thing that needs to be clarified is that redux-saga “call” test would not perform actual API call in testing, thus one would need to specify the sample result for the steps which may be used after the API call. Therefore before writing in redux-saga, it would be better to plan a saga and its corresponding sagas.spec.ts in detail.

  5. Redux-saga also provides many advanced features such as running tasks in parallel, concurrency helpers like takeLatest/takeEvery, fork/spawn, which are far more powerful than thunks.

In conclusion, personally, I would like to say: in many normal cases and small to medium size apps, go with async/await style redux-thunk. It would save you many boilerplate codes/actions/typedefs, and you would not need to switch around many different sagas.ts and maintain a specific sagas tree. But if you are developing a large app with much complex async logic and the need for features like concurrency/parallel pattern, or have a high demand for testing and maintenance (especially in test-driven development), redux-sagas would possibly save your life.

Anyway, redux-saga is not more difficult and complex than redux itself, and it does not have a so-called steep learning curve because it has well-limited core concepts and APIs. Spending a small amount of time learning redux-saga may benefit yourself one day in the future.

How to sort alphabetically while ignoring case sensitive?

In your comparator factory class, do something like this:

 private static final Comparator<String> MYSTRING_COMPARATOR = new Comparator<String>() {
    public int compare(String s1, String s2) {
      return s1.compareToIgnoreCase(s2);

  public static Comparator<String> getMyStringComparator() {

This uses the compare to method which is case insensitive (why write your own). This way you can use Collections sort like this:

List<String> myArray = new ArrayList<String>();
//fill your array here    
Collections.sort(MyArray, MyComparators. getMyStringComparator());

Convert String with Dot or Comma as decimal separator to number in JavaScript

All the other solutions require you to know the format in advance. I needed to detect(!) the format in every case and this is what I end up with.

function detectFloat(source) {
    let float = accounting.unformat(source);
    let posComma = source.indexOf(',');
    if (posComma > -1) {
        let posDot = source.indexOf('.');
        if (posDot > -1 && posComma > posDot) {
            let germanFloat = accounting.unformat(source, ',');
            if (Math.abs(germanFloat) > Math.abs(float)) {
                float = germanFloat;
        } else {
            // source = source.replace(/,/g, '.');
            float = accounting.unformat(source, ',');
    return float;

This was tested with the following cases:

        const cases = {
            "0": 0,
            "10.12": 10.12,
            "222.20": 222.20,
            "-222.20": -222.20,
            "+222,20": 222.20,
            "-222,20": -222.20,
            "-2.222,20": -2222.20,
            "-11.111,20": -11111.20,

Suggestions welcome.

cmake and libpthread

target_compile_options solution above is wrong, it won't link the library.




target_link_libraries(XXX PUBLIC pthread)


set_target_properties(XXX PROPERTIES LINK_LIBRARIES -pthread)

How to semantically add heading to a list

I put the heading inside the ul. There's no rule that says UL must contain only LI elements.

How to allow only integers in a textbox?

Just use

<input type="number" id="foo" runat="server" />

It'll work on all modern browsers except IE +10. Here is a full list:

Java Read Large Text File With 70million line of text

I tried the following three methods, my file size is 1M, and I got results:

enter image description here

I run the program several times it looks that BufferedReader is faster.

public void testLargeFileIO_Scanner() throws Exception {

    long start = new Date().getTime();

    String fileName = "/Downloads/SampleTextFile_1000kb.txt"; //this path is on my local
    InputStream inputStream = new FileInputStream(fileName);

    try (Scanner fileScanner = new Scanner(inputStream, {
        while (fileScanner.hasNextLine()) {
            String line = fileScanner.nextLine();
    long end = new Date().getTime();

    long time = end - start;
    System.out.println("Scanner Time Consumed => " + time);


 public void testLargeFileIO_BufferedReader() throws Exception {

    long start = new Date().getTime();

    String fileName = "/Downloads/SampleTextFile_1000kb.txt"; //this path is on my local
    try (BufferedReader fileBufferReader = new BufferedReader(new FileReader(fileName))) {
        String fileLineContent;
        while ((fileLineContent = fileBufferReader.readLine()) != null) {
    long end = new Date().getTime();

    long time = (long) (end - start);
    System.out.println("BufferedReader Time Consumed => " + time);


public void testLargeFileIO_Stream() throws Exception {

    long start = new Date().getTime();

    String fileName = "/Downloads/SampleTextFile_1000kb.txt"; //this path is on my local
    try (Stream inputStream = Files.lines(Paths.get(fileName), StandardCharsets.UTF_8)) {
    long end = new Date().getTime();

    long time = end - start;
    System.out.println("Stream Time Consumed => " + time);


Numpy Resize/Rescale Image

While it might be possible to use numpy alone to do this, the operation is not built-in. That said, you can use scikit-image (which is built on numpy) to do this kind of image manipulation.

Scikit-Image rescaling documentation is here.

For example, you could do the following with your image:

from skimage.transform import resize
bottle_resized = resize(bottle, (140, 54))

This will take care of things like interpolation, anti-aliasing, etc. for you.

What's the easy way to auto create non existing dir in ansible

If you are running Ansible >= 2.0 there is also the dirname filter you can use to extract the directory part of a path. That way you can just use one variable to hold the entire path to make sure both tasks never get out of sync.

So for example if you have playbook with dest_path defined in a variable like this you can reuse the same variable:

- name: My playbook
    dest_path: /home/ubuntu/some_dir/some_file.txt

    - name: Make sure destination dir exists
        path: "{{ dest_path | dirname }}"
        state: directory
        recurse: yes

    # now this task is always save to run no matter how dest_path get's changed arround
    - name: Add file or template to remote instance
        src: foo.txt.j2
        dest: "{{ dest_path }}"