Programs & Examples On #Jtag

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

Float and double datatype in Java

In regular programming calculations, we don’t use float. If we ensure that the result range is within the range of float data type then we can choose a float data type for saving memory. Generally, we use double because of two reasons:-

  • If we want to use the floating-point number as float data type then method caller must explicitly suffix F or f, because by default every floating-point number is treated as double. It increases the burden to the programmer. If we use a floating-point number as double data type then we don’t need to add any suffix.
  • Float is a single-precision data type means it occupies 4 bytes. Hence in large computations, we will not get a complete result. If we choose double data type, it occupies 8 bytes and we will get complete results.

Both float and double data types were designed especially for scientific calculations, where approximation errors are acceptable. If accuracy is the most prior concern then, it is recommended to use BigDecimal class instead of float or double data types. Source:- Float and double datatypes in Java

PHP Warning: POST Content-Length of 8978294 bytes exceeds the limit of 8388608 bytes in Unknown on line 0

From the XAMPP panel, click on the ADMIN button on the Apache site. Then choose to edit php.ini And add the missing post_max_size to a value you are comfortable with.

post_max_size = 100M

How do I create an .exe for a Java program?

If Java is installed on the target machine, there is no need to create an .exe file. A .jar file should be sufficient.

Java Multiple Inheritance

Ehm, your class can be the subclass for only 1 other, but still, you can have as many interfaces implemented, as you wish.

A Pegasus is in fact a horse (it is a special case of a horse), which is able to fly (which is the "skill" of this special horse). From the other hand, you can say, the Pegasus is a bird, which can walk, and is 4legged - it all depends, how it is easier for you to write the code.

Like in your case you can say:

abstract class Animal {
   private Integer hp = 0; 
   public void eat() { 
      hp++; 
   }
}
interface AirCompatible { 
   public void fly(); 
}
class Bird extends Animal implements AirCompatible { 
   @Override
   public void fly() {  
       //Do something useful
   }
} 
class Horse extends Animal {
   @Override
   public void eat() { 
      hp+=2; 
   }

}
class Pegasus extends Horse implements AirCompatible {
   //now every time when your Pegasus eats, will receive +2 hp  
   @Override
   public void fly() {  
       //Do something useful
   }
}

Spring boot Security Disable security

You need to add this entry to application.properties to bypass Springboot Default Security

spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.security.SecurityAutoConfiguration

Then there won't be any authentication box. otrws, credentials are:- user and 99b962fa-1848-4201-ae67-580bdeae87e9 (password randomly generated)

Note: my springBootVersion = '1.5.14.RELEASE'

jQuery get input value after keypress

Just use a timeout to make your call; the timeout will be called when the event stack is finished (i.e. after the default event is called)

$("body").on('keydown', 'input[type=tel]', function (e) {
    setTimeout(() => {
        formatPhone(e)
    }, 0)
});

Class has no member named

I know this is a year old but I just came across it with the same problem. My problem was that I didn't have a constructor in my implementation file. I think the problem here could be the comment marks at the end of the header file after the #endif...

Show all tables inside a MySQL database using PHP?

SHOW TABLE_NAME is not valid. Try SHOW TABLES

TD

Best way to create an empty map in Java

1) If the Map can be immutable:

Collections.emptyMap()

// or, in some cases:
Collections.<String, String>emptyMap()

You'll have to use the latter sometimes when the compiler cannot automatically figure out what kind of Map is needed (this is called type inference). For example, consider a method declared like this:

public void foobar(Map<String, String> map){ ... }

When passing the empty Map directly to it, you have to be explicit about the type:

foobar(Collections.emptyMap());                 // doesn't compile
foobar(Collections.<String, String>emptyMap()); // works fine

2) If you need to be able to modify the Map, then for example:

new HashMap<String, String>()

(as tehblanx pointed out)


Addendum: If your project uses Guava, you have the following alternatives:

1) Immutable map:

ImmutableMap.of()
// or:
ImmutableMap.<String, String>of()

Granted, no big benefits here compared to Collections.emptyMap(). From the Javadoc:

This map behaves and performs comparably to Collections.emptyMap(), and is preferable mainly for consistency and maintainability of your code.

2) Map that you can modify:

Maps.newHashMap()
// or:
Maps.<String, String>newHashMap()

Maps contains similar factory methods for instantiating other types of maps as well, such as TreeMap or LinkedHashMap.


Update (2018): On Java 9 or newer, the shortest code for creating an immutable empty map is:

Map.of()

...using the new convenience factory methods from JEP 269.

Are (non-void) self-closing tags valid in HTML5?

However -just for the record- this is invalid:

<address class="vcard">
  <svg viewBox="0 0 800 400">
    <rect width="800" height="400" fill="#000">
  </svg>
</address>

And a slash here would make it valid again:

    <rect width="800" height="400" fill="#000"/>

How to check whether the user uploaded a file in PHP?

You can use is_uploaded_file():

if(!file_exists($_FILES['myfile']['tmp_name']) || !is_uploaded_file($_FILES['myfile']['tmp_name'])) {
    echo 'No upload';
}

From the docs:

Returns TRUE if the file named by filename was uploaded via HTTP POST. This is useful to help ensure that a malicious user hasn't tried to trick the script into working on files upon which it should not be working--for instance, /etc/passwd.

This sort of check is especially important if there is any chance that anything done with uploaded files could reveal their contents to the user, or even to other users on the same system.

EDIT: I'm using this in my FileUpload class, in case it helps:

public function fileUploaded()
{
    if(empty($_FILES)) {
        return false;       
    } 
    $this->file = $_FILES[$this->formField];
    if(!file_exists($this->file['tmp_name']) || !is_uploaded_file($this->file['tmp_name'])){
        $this->errors['FileNotExists'] = true;
        return false;
    }   
    return true;
}

How to parse JSON using Node.js?

If you want to add some comments in your JSON and allow trailing commas you might want use below implemention:

var fs = require('fs');

var data = parseJsData('./message.json');

console.log('[INFO] data:', data);

function parseJsData(filename) {
    var json = fs.readFileSync(filename, 'utf8')
        .replace(/\s*\/\/.+/g, '')
        .replace(/,(\s*\})/g, '}')
    ;
    return JSON.parse(json);
}

Note that it might not work well if you have something like "abc": "foo // bar" in your JSON. So YMMV.

Upgrade python in a virtualenv

For everyone with the problem

Error: Command '['/Users/me/Sites/site/venv3/bin/python3', '-Im', 'ensurepip', '--upgrade', '--default-pip']' returned non-zero exit status 1.

You have to install python3.6-venv

 sudo apt-get install python3.6-venv

Copy existing project with a new name in Android Studio

As of February 2020, for Android Studio 3.5.3, the simplest answer I found is this video.

Note 1: At 01.24 "Find" tab appears below. Click "Do Refactor" and continue as in the video.

Note 2: If you have any Java/Kotlin files "Marked as Plain Text" you need to modify the package name at the top manually, i.e. package com.example.thisplaceneedstobemanuallyupdated

Note 3: Be careful about letter cases while renaming, just as in the video.

Note 4: If you want to update the project name on title bar of project window, modify rootProject.name = 'YourProjectName' inside "settings.gradle" file under "Gradle Scripts" directory.

DSO missing from command line

DSO here means Dynamic Shared Object; since the error message says it's missing from the command line, I guess you have to add it to the command line.

That is, try adding -lpthread to your command line.

How do I generate a random int number?

Sorry, OP indeed requires a random int value, but for the simple purpose to share knowledge if you want a random BigInteger value you can use following statement:

BigInteger randomVal = BigInteger.Abs(BigInteger.Parse(Guid.NewGuid().ToString().Replace("-",""), NumberStyles.AllowHexSpecifier));

Accidentally committed .idea directory files into git

Add .idea directory to the list of ignored files

First, add it to .gitignore, so it is not accidentally committed by you (or someone else) again:

.idea

Remove it from repository

Second, remove the directory only from the repository, but do not delete it locally. To achieve that, do what is listed here:

Remove a file from a Git repository without deleting it from the local filesystem

Send the change to others

Third, commit the .gitignore file and the removal of .idea from the repository. After that push it to the remote(s).

Summary

The full process would look like this:

$ echo '.idea' >> .gitignore
$ git rm -r --cached .idea
$ git add .gitignore
$ git commit -m '(some message stating you added .idea to ignored entries)'
$ git push

(optionally you can replace last line with git push some_remote, where some_remote is the name of the remote you want to push to)

How do I fix MSB3073 error in my post-build event?

Following thing you should do before to run copy command if you facing some issue with copy command

  1. open solution as a administrator and build the solution.
  2. if you have problem like "0 File(s) copied" check you source and destination path. might you are using wrong path. it would be better if you run the same command in "command prompt" to check whether it is working fine or not.

Bootstrap 3: Offset isn't working?

If I get you right, you want something that seems to be the opposite of what is desired normally: you want a horizontal layout for small screens and vertically stacked elements on large screens. You may achieve this in a way like this:

<div class="container">
    <div class="row">
        <div class="hidden-md hidden-lg col-xs-3 col-xs-offset-6">a</div>
        <div class="hidden-md hidden-lg col-xs-3">b</div>
    </div>
    <div class="row">
        <div class="hidden-xs hidden-sm">c</div>

    </div>
</div>

On small screens, i.e. xs and sm, this generates one row with two columns with an offset of 6. On larger screens, i.e. md and lg, it generates two vertically stacked elements in full width (12 columns).

How to select the row with the maximum value in each group

A dplyr solution:

library(dplyr)
ID <- c(1,1,1,2,2,2,2,3,3)
Value <- c(2,3,5,2,5,8,17,3,5)
Event <- c(1,1,2,1,2,1,2,2,2)
group <- data.frame(Subject=ID, pt=Value, Event=Event)

group %>%
    group_by(Subject) %>%
    summarize(max.pt = max(pt))

This yields the following data frame:

  Subject max.pt
1       1      5
2       2     17
3       3      5

How to represent a fix number of repeats in regular expression?

The finite repetition syntax uses {m,n} in place of star/plus/question mark.

From java.util.regex.Pattern:

X{n}      X, exactly n times
X{n,}     X, at least n times
X{n,m}    X, at least n but not more than m times

All repetition metacharacter have the same precedence, so just like you may need grouping for *, +, and ?, you may also for {n,m}.

  • ha* matches e.g. "haaaaaaaa"
  • ha{3} matches only "haaa"
  • (ha)* matches e.g. "hahahahaha"
  • (ha){3} matches only "hahaha"

Also, just like *, +, and ?, you can add the ? and + reluctant and possessive repetition modifiers respectively.

    System.out.println(
        "xxxxx".replaceAll("x{2,3}", "[x]")
    ); "[x][x]"

    System.out.println(
        "xxxxx".replaceAll("x{2,3}?", "[x]")
    ); "[x][x]x"

Essentially anywhere a * is a repetition metacharacter for "zero-or-more", you can use {...} repetition construct. Note that it's not true the other way around: you can use finite repetition in a lookbehind, but you can't use * because Java doesn't officially support infinite-length lookbehind.

References

Related questions

How to show loading spinner in jQuery?

This is the best way for me:

jQuery:

$(document).ajaxStart(function() {
  $(".loading").show();
});

$(document).ajaxStop(function() {
  $(".loading").hide();
});

Coffee:

  $(document).ajaxStart ->
    $(".loading").show()

  $(document).ajaxStop ->
    $(".loading").hide()

Docs: ajaxStart, ajaxStop

How to use paginator from material angular?

Another way to link Angular Paginator with the data table using Slice Pipe.Here data is fetched only once from server.

View:

 <div class="col-md-3" *ngFor="let productObj of productListData | 
     slice: lowValue : highValue">
       //actual data dispaly  
 </div>

<mat-paginator [length]="productListData.length" [pageSize]="pageSize" 
   (page)="pageEvent = getPaginatorData($event)">
</mat-paginator> 

Component

    pageIndex:number = 0;
    pageSize:number = 50;
    lowValue:number = 0;
    highValue:number = 50;       

  getPaginatorData(event){
     console.log(event);
     if(event.pageIndex === this.pageIndex + 1){
        this.lowValue = this.lowValue + this.pageSize;
        this.highValue =  this.highValue + this.pageSize;
       }
    else if(event.pageIndex === this.pageIndex - 1){
       this.lowValue = this.lowValue - this.pageSize;
       this.highValue =  this.highValue - this.pageSize;
      }   
       this.pageIndex = event.pageIndex;
 }

Installing Oracle Instant Client

If you want to use SQL Server Management Studio, you want to install the full Oracle client, not the Instant Client. The full Oracle client is on the same download page as the Oracle database. Assuming that you are installing on a 64-bit version of Windows, I expect you want the "Oracle Database 11g Release 2 Client (11.2.0.1.0) for Microsoft Windows (x64)" download. This is several hundred MB rather than a couple of MB for the Instant Client.

Confirmation before closing of tab/browser

The shortest solution for the year 2020 (for those happy people who don't need to support IE)

Tested in Chrome, Firefox, Safari.

function onBeforeUnload(e) {
    if (thereAreUnsavedChanges()) {
        e.preventDefault();
        e.returnValue = '';
        return;
    }

    delete e['returnValue'];
}

window.addEventListener('beforeunload', onBeforeUnload);

Actually no one modern browser (Chrome, Firefox, Safari) displays the "return value" as a question to user. Instead they show their own confirmation text (it depends on browser). But we still need to return some (even empty) string to trigger that confirmation on Chrome.

More explanations see on MDN here and here.

Mysql adding user for remote access

An alternative way is to use MySql Workbench. Go to Administration -> Users and privileges -> and change 'localhost' with '%' in 'Limit to Host Matching' (From host) attribute for users you wont to give remote access Or create new user ( Add account button ) with '%' on this attribute instead localhost.

How to get current available GPUs in tensorflow?

You can check all device list using following code:

from tensorflow.python.client import device_lib

device_lib.list_local_devices()

Get list from pandas DataFrame column headers

If the DataFrame happens to have an Index or MultiIndex and you want those included as column names too:

names = list(filter(None, df.index.names + df.columns.values.tolist()))

It avoids calling reset_index() which has an unnecessary performance hit for such a simple operation.

I've run into needing this more often because I'm shuttling data from databases where the dataframe index maps to a primary/unique key, but is really just another "column" to me. It would probably make sense for pandas to have a built-in method for something like this (totally possible I've missed it).

C# Wait until condition is true

After digging a lot of stuff, finally, I came up with a good solution that doesn't hang the CI :) Suit it to your needs!

public static Task WaitUntil<T>(T elem, Func<T, bool> predicate, int seconds = 10)
{
    var tcs = new TaskCompletionSource<int>();
    using(var cancellationTokenSource = new CancellationTokenSource(TimeSpan.FromSeconds(seconds)))
    {
        cancellationTokenSource.Token.Register(() =>
        {
            tcs.SetException(
                new TimeoutException($"Waiting predicate {predicate} for {elem.GetType()} timed out!"));
            tcs.TrySetCanceled();
        });

        while(!cancellationTokenSource.IsCancellationRequested)
        {
            try
            {
                if (!predicate(elem))
                {
                    continue;
                }
            }
            catch(Exception e)
            {
                tcs.TrySetException(e);
            }

            tcs.SetResult(0);
            break;
        }

        return tcs.Task;
    }
}

How to set the font size in Emacs?

I you're happy with console emacs (emacs -nw), modern vterm implementations (like gnome-terminal) tend to have better font support. Plus if you get used to that, you can then use tmux, and so working with your full environment on remote servers becomes possible, even without X.

What is the purpose of the vshost.exe file?

The vshost.exe file is the executable run by Visual Studio (Visual Studio host executable). This is the executable that links to Visual Studio and improves debugging.

When you're distributing your application to others, you do not use the vshost.exe or .pdb (debug database) files.

Is a GUID unique 100% of the time?

From http://www.guidgenerator.com/online-guid-generator.aspx

What is a GUID?

GUID (or UUID) is an acronym for 'Globally Unique Identifier' (or 'Universally Unique Identifier'). It is a 128-bit integer number used to identify resources. The term GUID is generally used by developers working with Microsoft technologies, while UUID is used everywhere else.

How unique is a GUID?

128-bits is big enough and the generation algorithm is unique enough that if 1,000,000,000 GUIDs per second were generated for 1 year the probability of a duplicate would be only 50%. Or if every human on Earth generated 600,000,000 GUIDs there would only be a 50% probability of a duplicate.

ANTLR: Is there a simple example?

Note: this answer is for ANTLR3! If you're looking for an ANTLR4 example, then this Q&A demonstrates how to create a simple expression parser, and evaluator using ANTLR4.


You first create a grammar. Below is a small grammar that you can use to evaluate expressions that are built using the 4 basic math operators: +, -, * and /. You can also group expressions using parenthesis.

Note that this grammar is just a very basic one: it does not handle unary operators (the minus in: -1+9) or decimals like .99 (without a leading number), to name just two shortcomings. This is just an example you can work on yourself.

Here's the contents of the grammar file Exp.g:

grammar Exp;

/* This will be the entry point of our parser. */
eval
    :    additionExp
    ;

/* Addition and subtraction have the lowest precedence. */
additionExp
    :    multiplyExp 
         ( '+' multiplyExp 
         | '-' multiplyExp
         )* 
    ;

/* Multiplication and division have a higher precedence. */
multiplyExp
    :    atomExp
         ( '*' atomExp 
         | '/' atomExp
         )* 
    ;

/* An expression atom is the smallest part of an expression: a number. Or 
   when we encounter parenthesis, we're making a recursive call back to the
   rule 'additionExp'. As you can see, an 'atomExp' has the highest precedence. */
atomExp
    :    Number
    |    '(' additionExp ')'
    ;

/* A number: can be an integer value, or a decimal value */
Number
    :    ('0'..'9')+ ('.' ('0'..'9')+)?
    ;

/* We're going to ignore all white space characters */
WS  
    :   (' ' | '\t' | '\r'| '\n') {$channel=HIDDEN;}
    ;

(Parser rules start with a lower case letter, and lexer rules start with a capital letter)

After creating the grammar, you'll want to generate a parser and lexer from it. Download the ANTLR jar and store it in the same directory as your grammar file.

Execute the following command on your shell/command prompt:

java -cp antlr-3.2.jar org.antlr.Tool Exp.g

It should not produce any error message, and the files ExpLexer.java, ExpParser.java and Exp.tokens should now be generated.

To see if it all works properly, create this test class:

import org.antlr.runtime.*;

public class ANTLRDemo {
    public static void main(String[] args) throws Exception {
        ANTLRStringStream in = new ANTLRStringStream("12*(5-6)");
        ExpLexer lexer = new ExpLexer(in);
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        ExpParser parser = new ExpParser(tokens);
        parser.eval();
    }
}

and compile it:

// *nix/MacOS
javac -cp .:antlr-3.2.jar ANTLRDemo.java

// Windows
javac -cp .;antlr-3.2.jar ANTLRDemo.java

and then run it:

// *nix/MacOS
java -cp .:antlr-3.2.jar ANTLRDemo

// Windows
java -cp .;antlr-3.2.jar ANTLRDemo

If all goes well, nothing is being printed to the console. This means the parser did not find any error. When you change "12*(5-6)" into "12*(5-6" and then recompile and run it, there should be printed the following:

line 0:-1 mismatched input '<EOF>' expecting ')'

Okay, now we want to add a bit of Java code to the grammar so that the parser actually does something useful. Adding code can be done by placing { and } inside your grammar with some plain Java code inside it.

But first: all parser rules in the grammar file should return a primitive double value. You can do that by adding returns [double value] after each rule:

grammar Exp;

eval returns [double value]
    :    additionExp
    ;

additionExp returns [double value]
    :    multiplyExp 
         ( '+' multiplyExp 
         | '-' multiplyExp
         )* 
    ;

// ...

which needs little explanation: every rule is expected to return a double value. Now to "interact" with the return value double value (which is NOT inside a plain Java code block {...}) from inside a code block, you'll need to add a dollar sign in front of value:

grammar Exp;

/* This will be the entry point of our parser. */
eval returns [double value]                                                  
    :    additionExp { /* plain code block! */ System.out.println("value equals: "+$value); }
    ;

// ...

Here's the grammar but now with the Java code added:

grammar Exp;

eval returns [double value]
    :    exp=additionExp {$value = $exp.value;}
    ;

additionExp returns [double value]
    :    m1=multiplyExp       {$value =  $m1.value;} 
         ( '+' m2=multiplyExp {$value += $m2.value;} 
         | '-' m2=multiplyExp {$value -= $m2.value;}
         )* 
    ;

multiplyExp returns [double value]
    :    a1=atomExp       {$value =  $a1.value;}
         ( '*' a2=atomExp {$value *= $a2.value;} 
         | '/' a2=atomExp {$value /= $a2.value;}
         )* 
    ;

atomExp returns [double value]
    :    n=Number                {$value = Double.parseDouble($n.text);}
    |    '(' exp=additionExp ')' {$value = $exp.value;}
    ;

Number
    :    ('0'..'9')+ ('.' ('0'..'9')+)?
    ;

WS  
    :   (' ' | '\t' | '\r'| '\n') {$channel=HIDDEN;}
    ;

and since our eval rule now returns a double, change your ANTLRDemo.java into this:

import org.antlr.runtime.*;

public class ANTLRDemo {
    public static void main(String[] args) throws Exception {
        ANTLRStringStream in = new ANTLRStringStream("12*(5-6)");
        ExpLexer lexer = new ExpLexer(in);
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        ExpParser parser = new ExpParser(tokens);
        System.out.println(parser.eval()); // print the value
    }
}

Again (re) generate a fresh lexer and parser from your grammar (1), compile all classes (2) and run ANTLRDemo (3):

// *nix/MacOS
java -cp antlr-3.2.jar org.antlr.Tool Exp.g   // 1
javac -cp .:antlr-3.2.jar ANTLRDemo.java      // 2
java -cp .:antlr-3.2.jar ANTLRDemo            // 3

// Windows
java -cp antlr-3.2.jar org.antlr.Tool Exp.g   // 1
javac -cp .;antlr-3.2.jar ANTLRDemo.java      // 2
java -cp .;antlr-3.2.jar ANTLRDemo            // 3

and you'll now see the outcome of the expression 12*(5-6) printed to your console!

Again: this is a very brief explanation. I encourage you to browse the ANTLR wiki and read some tutorials and/or play a bit with what I just posted.

Good luck!

EDIT:

This post shows how to extend the example above so that a Map<String, Double> can be provided that holds variables in the provided expression.

To get this code working with a current version of Antlr (June 2014) I needed to make a few changes. ANTLRStringStream needed to become ANTLRInputStream, the returned value needed to change from parser.eval() to parser.eval().value, and I needed to remove the WS clause at the end, because attribute values such as $channel are no longer allowed to appear in lexer actions.

How to develop a soft keyboard for Android?

A good place to start is the sample application provided on the developer docs.

  • Guidelines would be to just make it as usable as possible. Take a look at the others available on the market to see what you should be aiming for
  • Yes, services can do most things, including internet; provided you have asked for those permissions
  • You can open activities and do anything you like n those if you run into a problem with doing some things in the keyboard. For example HTC's keyboard has a button to open the settings activity, and another to open a dialog to change languages.

Take a look at other IME's to see what you should be aiming for. Some (like the official one) are open source.

jQuery - Increase the value of a counter when a button is clicked

I'm going to try this the following way. I've placed the count variable inside the "onfocus" function so as to keep it from becoming a global variable. The idea is to create a counter for each image in a tumblr blog.

$(document).ready(function() {

  $("#image1").onfocus(function() {

  var count;

    if (count == undefined || count == "" || count == 0) {
    var count = 0;
    }

    count++;
    $("#counter1").html("Image Views: " + count);
  }
});

Then, outside the script tags and in the desired place in the body I'll add:

<div id="counter1"></div>

VBA Excel Provide current Date in Text box

Set the value from code on showing the form, not in the design-timeProperties for the text box.

Private Sub UserForm_Activate()
    Me.txtDate.Value = Format(Date, "mm/dd/yy")
End Sub

How do I force my .NET application to run as administrator?

Adding a requestedExecutionLevel element to your manifest is only half the battle; you have to remember that UAC can be turned off. If it is, you have to perform the check the old school way and put up an error dialog if the user is not administrator
(call IsInRole(WindowsBuiltInRole.Administrator) on your thread's CurrentPrincipal).

How do I fix twitter-bootstrap on IE?

Just for completeness - it's worth noting that with Bootstrap 3, as per the docs, ensure the following structure in your page. It solved issues I was having with IE9 and v3.

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<!-- content -->
</body>
</html>

Webpack.config how to just copy the index.html to the dist folder

This work well on Windows:

  1. npm install --save-dev copyfiles
  2. In package.json I have a copy task : "copy": "copyfiles -u 1 ./app/index.html ./deploy"

This move my index.html from the app folder into the deploy folder.

How to convert all elements in an array to integer in JavaScript?

If you want to convert an Array of digits to a single number just use:

Number(arrayOfDigits.join(''));

Example

const arrayOfDigits = [1,2,3,4,5];

const singleNumber = Number(arrayOfDigits.join(''));

console.log(singleNumber); //12345

Facebook Like-Button - hide count?

All you need to do is edit the iframe code that facebook gives you and change the width to 47 (you need to change it in 2 places). Seems to work perfectly for me so far.

Maven not found in Mac OSX mavericks

For me trying above techniques did work so I opened .bash_profile file and added following line in new line to connect to maven using short cmd :

alias mvn=/opt/apache-maven-3.6.3/bin/mvn

Restart your terminal and hit mvn clean install cmd

How to format a QString?

Use QString::arg() for the same effect.

Insert variable into Header Location PHP

Try using double quotes and keeping the L in location lowercase...

header("location: http://linkhere.com/HERE_I_WANT_THE_VARIABLE");

or for example

header("location: http://linkhere.com/$variable");

No need to concatenate here to insert variables.

The operation couldn’t be completed. (com.facebook.sdk error 2.) ios6

check your Bundle identifier for your project and you give Bundle identifier for your app which create on developer.facebook.com that they are same or not.

How do I capture SIGINT in Python?

You can handle CTRL+C by catching the KeyboardInterrupt exception. You can implement any clean-up code in the exception handler.

What is the use of printStackTrace() method in Java?

printStackTrace() helps the programmer to understand where the actual problem occurred. printStacktrace() is a method of the class Throwable of java.lang package. It prints several lines in the output console. The first line consists of several strings. It contains the name of the Throwable sub-class & the package information. From second line onwards, it describes the error position/line number beginning with at.

The last line always describes the destination affected by the error/exception. The second last line informs us about the next line in the stack where the control goes after getting transfer from the line number described in the last line. The errors/exceptions represents the output in the form a stack, which were fed into the stack by fillInStackTrace() method of Throwable class, which itself fills in the program control transfer details into the execution stack. The lines starting with at, are nothing but the values of the execution stack. In this way the programmer can understand where in code the actual problem is.

Along with the printStackTrace() method, it's a good idea to use e.getmessage().

Re-doing a reverted merge in Git

Let's assume you have such history

---o---o---o---M---W---x-------x-------*
              /                      
      ---A---B

Where A, B failed commits and W - is revert of M

So before I start fixing found problems I do cherry-pick of W commit to my branch

git cherry-pick -x W

Then I revert W commit on my branch

git revert W 

After I can continue fixing.

The final history could look like:

---o---o---o---M---W---x-------x-------*
              /                       /     
      ---A---B---W---W`----------C---D

When I send a PR it will clearly shows that PR is undo revert and adds some new commits.

How to use lifecycle method getDerivedStateFromProps as opposed to componentWillReceiveProps

About the removal of componentWillReceiveProps: you should be able to handle its uses with a combination of getDerivedStateFromProps and componentDidUpdate, see the React blog post for example migrations. And yes, the object returned by getDerivedStateFromProps updates the state similarly to an object passed to setState.

In case you really need the old value of a prop, you can always cache it in your state with something like this:

state = {
  cachedSomeProp: null
  // ... rest of initial state
};

static getDerivedStateFromProps(nextProps, prevState) {
  // do things with nextProps.someProp and prevState.cachedSomeProp
  return {
    cachedSomeProp: nextProps.someProp,
    // ... other derived state properties
  };
}

Anything that doesn't affect the state can be put in componentDidUpdate, and there's even a getSnapshotBeforeUpdate for very low-level stuff.

UPDATE: To get a feel for the new (and old) lifecycle methods, the react-lifecycle-visualizer package may be helpful.

How to change the name of a Django app?

In many cases, I believe @allcaps's answer works well.

However, sometimes it is necessary to actually rename an app, e.g. to improve code readability or prevent confusion.

Most of the other answers involve either manual database manipulation or tinkering with existing migrations, which I do not like very much.

As an alternative, I like to create a new app with the desired name, copy everything over, make sure it works, then remove the original app:

  1. Start a new app with the desired name, and copy all code from the original app into that. Make sure you fix the namespaced stuff, in the newly copied code, to match the new app name.

  2. makemigrations and migrate

  3. Create a data migration that copies the relevant data from the original app's tables into the new app's tables, and migrate again.

At this point, everything still works, because the original app and its data are still in place.

  1. Now you can refactor all the dependent code, so it only makes use of the new app. See other answers for examples of what to look out for.

  2. Once you are certain that everything works, you can remove the original app.

This has the advantage that every step uses the normal Django migration mechanism, without manual database manipulation, and we can track everything in source control. In addition, we keep the original app and its data in place until we are sure everything works.

How to link C++ program with Boost using CMake

Two ways, using system default install path, usually /usr/lib/x86_64-linux-gnu/:

find_package(Boost REQUIRED regex date_time system filesystem thread graph)
include_directories(${BOOST_INCLUDE_DIRS})
message("boost lib: ${Boost_LIBRARIES}")
message("boost inc:${Boost_INCLUDE_DIR}")

add_executable(use_boost use_boost.cpp)
target_link_libraries(use_boost
        ${Boost_LIBRARIES}
        )

If you install Boost in a local directory or choose local install instead of system install, you can do it by this:

set( BOOST_ROOT "/home/xy/boost_install/lib/" CACHE PATH "Boost library path" )
set( Boost_NO_SYSTEM_PATHS on CACHE BOOL "Do not search system for Boost" )

find_package(Boost REQUIRED regex date_time system filesystem thread graph)
include_directories(${BOOST_INCLUDE_DIRS})
message("boost lib: ${Boost_LIBRARIES}, inc:${Boost_INCLUDE_DIR}")

add_executable(use_boost use_boost.cpp)
target_link_libraries(use_boost
        ${Boost_LIBRARIES}
        )

Note the above dir /home/xy/boost_install/lib/ is where I install Boost:

xy@xy:~/boost_install/lib$ ll -th
total 16K
drwxrwxr-x 2 xy xy 4.0K May 28 19:23 lib/
drwxrwxr-x 3 xy xy 4.0K May 28 19:22 include/

xy@xy:~/boost_install/lib$ ll -th lib/
total 57M
drwxrwxr-x 2 xy xy 4.0K May 28 19:23 ./
-rw-rw-r-- 1 xy xy 2.3M May 28 19:23 libboost_test_exec_monitor.a
-rw-rw-r-- 1 xy xy 2.2M May 28 19:23 libboost_unit_test_framework.a
.......

xy@xy:~/boost_install/lib$ ll -th include/
total 20K
drwxrwxr-x 110 xy xy  12K May 28 19:22 boost/

If you are interested in how to use a local installed Boost, you can see this question How can I get CMake to find my alternative Boost installation?.

Cannot get to $rootScope

I don't suggest you to use syntax like you did. AngularJs lets you to have different functionalities as you want (run, config, service, factory, etc..), which are more professional.In this function you don't even have to inject that by yourself like

MainCtrl.$inject = ['$scope', '$rootScope', '$location', 'socket', ...];

you can use it, as you know.

How to count items in JSON object using command line?

Just throwing another solution in the mix...

Try jq, a lightweight and flexible command-line JSON processor:

jq length /tmp/test.json

Prints the length of the array of objects.

Sending JSON object to Web API

I believe you need quotes around the model:

JSON.stringify({ "model": source })

Setting the number of map tasks and reduce tasks

  • Use -D property=value rather than -D property = value (eliminate extra whitespaces). Thus -D mapred.reduce.tasks=value would work fine.

  • Setting number of map tasks doesnt always reflect the value you have set since it depends on split size and InputFormat used.

  • Setting the number of reduces will definitely override the number of reduces set on cluster/client-side configuration.

How to make flexbox items the same size?

The accepted answer by Adam (flex: 1 1 0) works perfectly for flexbox containers whose width is either fixed, or determined by an ancestor. Situations where you want the children to fit the container.

However, you may have a situation where you want the container to fit the children, with the children equally sized based on the largest child. You can make a flexbox container fit its children by either:

  • setting position: absolute and not setting width or right, or
  • place it inside a wrapper with display: inline-block

For such flexbox containers, the accepted answer does NOT work, the children are not sized equally. I presume that this is a limitation of flexbox, since it behaves the same in Chrome, Firefox and Safari.

The solution is to use a grid instead of a flexbox.

Demo: https://codepen.io/brettdonald/pen/oRpORG

<p>Normal scenario — flexbox where the children adjust to fit the container — and the children are made equal size by setting {flex: 1 1 0}</p>

<div id="div0">
  <div>
    Flexbox
  </div>
  <div>
    Width determined by viewport
  </div>
  <div>
    All child elements are equal size with {flex: 1 1 0}
  </div>
</div>

<p>Now we want to have the container fit the children, but still have the children all equally sized, based on the largest child. We can see that {flex: 1 1 0} has no effect.</p>

<div class="wrap-inline-block">
<div id="div1">
  <div>
    Flexbox
  </div>
  <div>
    Inside inline-block
  </div>
  <div>
    We want all children to be the size of this text
  </div>
</div>
</div>

<div id="div2">
  <div>
    Flexbox
  </div>
  <div>
    Absolutely positioned
  </div>
  <div>
    We want all children to be the size of this text
  </div>
</div>

<br><br><br><br><br><br>
<p>So let's try a grid instead. Aha! That's what we want!</p>

<div class="wrap-inline-block">
<div id="div3">
  <div>
    Grid
  </div>
  <div>
    Inside inline-block
  </div>
  <div>
    We want all children to be the size of this text
  </div>
</div>
</div>

<div id="div4">
  <div>
    Grid
  </div>
  <div>
    Absolutely positioned
  </div>
  <div>
    We want all children to be the size of this text
  </div>
</div>
body {
  margin: 1em;
}

.wrap-inline-block {
  display: inline-block;
}

#div0, #div1, #div2, #div3, #div4 {
  border: 1px solid #888;
  padding: 0.5em;
  text-align: center;
  white-space: nowrap;
}

#div2, #div4 {
  position: absolute;
  left: 1em;
}

#div0>*, #div1>*, #div2>*, #div3>*, #div4>* {
  margin: 0.5em;
  color: white;
  background-color: navy;
  padding: 0.5em;
}

#div0, #div1, #div2 {
  display: flex;
}

#div0>*, #div1>*, #div2>* {
  flex: 1 1 0;
}

#div0 {
  margin-bottom: 1em;
}

#div2 {
  top: 15.5em;
}

#div3, #div4 {
  display: grid;
  grid-template-columns: repeat(3,1fr);
}

#div4 {
  top: 28.5em;
}

What does [object Object] mean?

As others have noted, this is the default serialisation of an object. But why is it [object Object] and not just [object]?

That is because there are different types of objects in Javascript!

  • Function objects:
    stringify(function (){}) -> [object Function]
  • Array objects:
    stringify([]) -> [object Array]
  • RegExp objects
    stringify(/x/) -> [object RegExp]
  • Date objects
    stringify(new Date) -> [object Date]
  • several more
  • and Object objects!
    stringify({}) -> [object Object]

That's because the constructor function is called Object (with a capital "O"), and the term "object" (with small "o") refers to the structural nature of the thingy.

Usually, when you're talking about "objects" in Javascript, you actually mean "Object objects", and not the other types.

where stringify should look like this:

function stringify (x) {
    console.log(Object.prototype.toString.call(x));
}

How to resolve ambiguous column names when retrieving results?

You can set aliases for the columns that you are selecting:

$query = 'SELECT news.id AS newsId, user.id AS userId, [OTHER FIELDS HERE] FROM news JOIN users ON news.user = user.id'

How to have jQuery restrict file types on upload?

Don't want to check rather on MIME than on whatever extention the user is lying? If so then it's less than one line:

<input type="file" id="userfile" accept="image/*|video/*" required />

On select change, get data attribute value

You can use context syntax with this or $(this). This is the same effect as find().

_x000D_
_x000D_
$('select').change(function() {_x000D_
    console.log('Clicked option value => ' + $(this).val());_x000D_
    <!-- undefined console.log('$(this) without explicit :select => ' + $(this).data('id')); -->_x000D_
    <!-- error console.log('this without explicit :select => ' + this.data('id')); -->_x000D_
    console.log(':select & $(this) =>    ' + $(':selected', $(this)).data('id'));_x000D_
    console.log(':select & this =>       ' + $(':selected', this).data('id'));_x000D_
    console.log('option:select & this => ' + $('option:selected', this).data('id'));_x000D_
    console.log('$(this) & find =>       ' + $(this).find(':selected').data('id'));_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<select>_x000D_
    <option data-id="1">one</option>_x000D_
    <option data-id="2">two</option>_x000D_
    <option data-id="3">three</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

As a matter of microoptimization, you might opt for find(). If you are more of a code golfer, the context syntax is more brief. It comes down to coding style basically.

Here is a relevant performance comparison.

How can I make a menubar fixed on the top while scrolling

This should get you started

 <div class="menuBar">
        <img class="logo" src="logo.jpg"/>
        <div class="nav"> 
            <ul>
                <li>Menu1</li>
                <li>Menu 2</li>
                <li>Menu 3</li>
            </ul> 
        </div>
    </div>



body{
    margin-top:50px;}
.menuBar{
    width:100%;
    height:50px;
    display:block;
    position:absolute;
    top:0;
    left:0;
    }
.logo{
    float:left;
    }
.nav{
    float:right;
    margin-right:10px;}
.nav ul li{
    list-style:none;
    float:left;
    }

What to do with "Unexpected indent" in python?

Make sure you use the option "insert spaces instead of tabs" in your editor. Then you can choose you want a tab width of, for example 4. You can find those options in gedit under edit-->preferences-->editor.

bottom line: USE SPACES not tabs

What's the difference between abstraction and encapsulation?

In my opinion, both terms are related in some sense and sort of mixed into each other. "Encapsulation" provides a way to grouping related fields, methods in a class (or module) to wrap the related things together. As of that time, it provides data hiding in two ways;

  1. Through access modifiers.

    Purely for hiding state of the class/object.

  2. Abstracting some functionalities.

    a. Through interfaces/abstract classes, complex logic inside the encapsulated class or module can be abstracted/generalized to be used by outside.

    b. Through function signatures. Yes, even function signatures example of abstracting. Because callers only knows the signature and parameters (if any) and know nothing about how the function is carried out. It only cares of returned value.

Likewise, "Abstraction" might be think of a way of encapsulation in terms of grouping/wrapping the behaviour into an interface (or abstract class or might be even a normal class ).

Regex Named Groups in Java

For those running pre-java7, named groups are supported by joni (Java port of the Oniguruma regexp library). Documentation is sparse, but it has worked well for us.
Binaries are available via Maven (http://repository.codehaus.org/org/jruby/joni/joni/).

Response.Redirect with POST instead of Get?

HttpWebRequest is used for this.

On postback, create a HttpWebRequest to your third party and post the form data, then once that is done, you can Response.Redirect wherever you want.

You get the added advantage that you don't have to name all of your server controls to make the 3rd parties form, you can do this translation when building the POST string.

string url = "3rd Party Url";

StringBuilder postData = new StringBuilder();

postData.Append("first_name=" + HttpUtility.UrlEncode(txtFirstName.Text) + "&");
postData.Append("last_name=" + HttpUtility.UrlEncode(txtLastName.Text));

//ETC for all Form Elements

// Now to Send Data.
StreamWriter writer = null;

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";                        
request.ContentLength = postData.ToString().Length;
try
{
    writer = new StreamWriter(request.GetRequestStream());
    writer.Write(postData.ToString());
}
finally
{
    if (writer != null)
        writer.Close();
}

Response.Redirect("NewPage");

However, if you need the user to see the response page from this form, your only option is to utilize Server.Transfer, and that may or may not work.

Why do we use Base64?

Media that is designed for textual data is of course eventually binary as well, but textual media often use certain binary values for control characters. Also, textual media may reject certain binary values as non-text.

Base64 encoding encodes binary data as values that can only be interpreted as text in textual media, and is free of any special characters and/or control characters, so that the data will be preserved across textual media as well.

How to remove the URL from the printing page?

I would agree with most of the answers saying that its a browser settings but still you can achieve what you want via COM. Keep in mind that most browsers will still have issue with that and even IE will raise the COM security bar to users. So unless its not something you are offering within organisation, don't do it.

How to verify static void method has been called with power mockito

If you are mocking the behavior (with something like doNothing()) there should really be no need to call to verify*(). That said, here's my stab at re-writing your test method:

@PrepareForTest({InternalUtils.class})
@RunWith(PowerMockRunner.class)
public class InternalServiceTest { //Note the renaming of the test class.
   public void testProcessOrder() {
        //Variables
        InternalService is = new InternalService();
        Order order = mock(Order.class);

        //Mock Behavior
        when(order.isSuccessful()).thenReturn(true);
        mockStatic(Internalutils.class);
        doNothing().when(InternalUtils.class); //This is the preferred way
                                               //to mock static void methods.
        InternalUtils.sendEmail(anyString(), anyString(), anyString(), anyString());

        //Execute
        is.processOrder(order);            

        //Verify
        verifyStatic(InternalUtils.class); //Similar to how you mock static methods
                                           //this is how you verify them.
        InternalUtils.sendEmail(anyString(), anyString(), anyString(), anyString());
   }
}

I grouped into four sections to better highlight what is going on:

1. Variables

I choose to declare any instance variables / method arguments / mock collaborators here. If it is something used in multiple tests, consider making it an instance variable of the test class.

2. Mock Behavior

This is where you define the behavior of all of your mocks. You're setting up return values and expectations here, prior to executing the code under test. Generally speaking, if you set the mock behavior here you wouldn't need to verify the behavior later.

3. Execute

Nothing fancy here; this just kicks off the code being tested. I like to give it its own section to call attention to it.

4. Verify

This is when you call any method starting with verify or assert. After the test is over, you check that the things you wanted to have happen actually did happen. That is the biggest mistake I see with your test method; you attempted to verify the method call before it was ever given a chance to run. Second to that is you never specified which static method you wanted to verify.

Additional Notes

This is mostly personal preference on my part. There is a certain order you need to do things in but within each grouping there is a little wiggle room. This helps me quickly separate out what is happening where.

I also highly recommend going through the examples at the following sites as they are very robust and can help with the majority of the cases you'll need:

How to get the date 7 days earlier date from current date in Java

You can use this to continue using the type Date and a more legible code, if you preffer:

import org.apache.commons.lang.time.DateUtils;
...
Date yourDate = DateUtils.addDays(new Date(), *days here*);

Android background music service

Do it without service

https://web.archive.org/web/20181116173307/http://www.rbgrn.net/content/307-light-racer-20-days-61-64-completion

If you are so serious about doing it with services using mediaplayer

Intent svc=new Intent(this, BackgroundSoundService.class);
startService(svc);

public class BackgroundSoundService extends Service {
    private static final String TAG = null;
    MediaPlayer player;
    public IBinder onBind(Intent arg0) {

        return null;
    }
    @Override
    public void onCreate() {
        super.onCreate();
        player = MediaPlayer.create(this, R.raw.idil);
        player.setLooping(true); // Set looping
        player.setVolume(100,100);

    }
    public int onStartCommand(Intent intent, int flags, int startId) {
        player.start();
        return 1;
    }

    public void onStart(Intent intent, int startId) {
        // TO DO
    }
    public IBinder onUnBind(Intent arg0) {
        // TO DO Auto-generated method
        return null;
    }

    public void onStop() {

    }
    public void onPause() {

    }
    @Override
    public void onDestroy() {
        player.stop();
        player.release();
    }

    @Override
    public void onLowMemory() {

    }
}

Please call this service in Manifest Make sure there is no space at the end of the .BackgroundSoundService string

<service android:enabled="true" android:name=".BackgroundSoundService" />

How to Write text file Java

It does work with me. Make sure that you append ".txt" next to timeLog. I used it in a simple program opened with Netbeans and it writes the program in the main folder (where builder and src folders are).

What is the common header format of Python files?

The answers above are really complete, but if you want a quick and dirty header to copy'n paste, use this:

#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""Module documentation goes here
   and here
   and ...
"""

Why this is a good one:

  • The first line is for *nix users. It will choose the Python interpreter in the user path, so will automatically choose the user preferred interpreter.
  • The second one is the file encoding. Nowadays every file must have a encoding associated. UTF-8 will work everywhere. Just legacy projects would use other encoding.
  • And a very simple documentation. It can fill multiple lines.

See also: https://www.python.org/dev/peps/pep-0263/

If you just write a class in each file, you don't even need the documentation (it would go inside the class doc).

html5 audio player - jquery toggle click play/pause?

You can call native methods trough trigger in jQuery. Just do this:

$('.play').trigger("play");

And the same for pause: $('.play').trigger("pause");

EDIT: as F... pointed out in the comments, you can do something similar to access properties: $('.play').prop("paused");

OraOLEDB.Oracle provider is not registered on the local machine

  1. Right Click on My Computer
  2. Click on properties
  3. Click on Advanced System Settings
  4. Click on "Environment Variables" button.
  5. In the system Variable section find the "PATH" variable
  6. Edit the "PATH" variable and add Oracle installation path to it (from your local machine) like ;C:\oracle\product\10.2.0\client_1\bin

Rename file with Git

Do a git status to find out if your file is actually in your index or the commit.

It is easy as a beginner to misunderstand the index/staging area.

I view it as a 'progress pinboard'. I therefore have to add the file to the pinboard before I can commit it (i.e. a copy of the complete pinboard), I have to update the pinboard when required, and I also have to deliberately remove files from it when I've finished with them - simply creating, editing or deleting a file doesn't affect the pinboard. It's like 'storyboarding'.

Edit: As others noted, You should do the edits locally and then push the updated repo, rather than attempt to edit directly on github.

Java File - Open A File And Write To It

Suggestions:

  • Create a File object that refers to the already existing file on disk.
  • Use a FileWriter object, and use the constructor that takes the File object and a boolean, the latter if true would allow appending text into the File if it exists.
  • Then initialize a PrintWriter passing in the FileWriter into its constructor.
  • Then call println(...) on your PrintWriter, writing your new text into the file.
  • As always, close your resources (the PrintWriter) when you are done with it.
  • As always, don't ignore exceptions but rather catch and handle them.
  • The close() of the PrintWriter should be in the try's finally block.

e.g.,

  PrintWriter pw = null;

  try {
     File file = new File("fubars.txt");
     FileWriter fw = new FileWriter(file, true);
     pw = new PrintWriter(fw);
     pw.println("Fubars rule!");
  } catch (IOException e) {
     e.printStackTrace();
  } finally {
     if (pw != null) {
        pw.close();
     }
  }

Easy, no?

PHP __get and __set magic methods

I'd recommend to use an array for storing all values via __set().

class foo {

    protected $values = array();

    public function __get( $key )
    {
        return $this->values[ $key ];
    }

    public function __set( $key, $value )
    {
        $this->values[ $key ] = $value;
    }

}

This way you make sure, that you can't access the variables in another way (note that $values is protected), to avoid collisions.

Easiest way to convert month name to month number in JS ? (Jan = 01)

If you are using moment.js:

moment().month("Jan").format("M");

Decreasing for loops in Python impossible?

>>> range(6, 0, -1)
[6, 5, 4, 3, 2, 1]

How to resize Twitter Bootstrap modal dynamically based on the content

There are many ways to do this if you want to write css then add following

.modal-dialog{
  display: table
}

In case if you want to add inline

<div class="modal-dialog" style="display:table;">
//enter code here
</div>

Don't add display:table; to modal-content class. it done your job but disposition your modal for large size see following screenshots. first image is if you add style to modal-dialog In case if you add style to modal-dialog if you add style to modal-content. it looks dispositioned. enter image description here

How to fix: fatal error: openssl/opensslv.h: No such file or directory in RedHat 7

To fix this problem, you have to install OpenSSL development package, which is available in standard repositories of all modern Linux distributions.

To install OpenSSL development package on Debian, Ubuntu or their derivatives:

$ sudo apt-get install libssl-dev

To install OpenSSL development package on Fedora, CentOS or RHEL:

$ sudo yum install openssl-devel 

Edit : As @isapir has pointed out, for Fedora version>=22 use the DNF package manager :

dnf install openssl-devel

How does Tomcat locate the webapps directory?

Change appBase in server.xml

If you want to keep both previous webapps and a new one, you can use another Host instance with another port defined in tomcat.

How can I clear the terminal in Visual Studio Code?

Ctrl + Shift + P and select Terminal:clear

How do you setLayoutParams() for an ImageView?

Old thread but I had the same problem now. If anyone encounters this he'll probably find this answer:

LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(30, 30);
yourImageView.setLayoutParams(layoutParams);

This will work only if you add the ImageView as a subView to a LinearLayout. If you add it to a RelativeLayout you will need to call:

RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(30, 30);
yourImageView.setLayoutParams(layoutParams);

Access a JavaScript variable from PHP

Well the problem with the GET is that the user is able to change the value by himself if he has some knowledges. I wrote this so that PHP is able to retrive the timezone from Javascript:

// -- index.php

<?php
  if (!isset($_COOKIE['timezone'])) {
?>
<html>
<script language="javascript">  
  var d = new Date(); 
  var timezoneOffset = d.getTimezoneOffset() / 60;
  // the cookie expired in 3 hours
  d.setTime(d.getTime()+(3*60*60*1000));
  var expires = "; expires="+d.toGMTString();
  document.cookie = "timezone=" +  timezoneOffset + expires + "; path=/";
  document.location.href="index.php"
</script>
</html>
<?php
} else {
  ?>

  <html>
  <head>
  <body>

  <?php 
  if(isset($_COOKIE['timezone'])){ 
    dump_var($_COOKIE['timezone']); 
  } 
}
?>

Android Studio - Failed to notify project evaluation listener error

With the new google support gradle plugin (com.google.gms.google-services) this can be caused by some dependency version problems with your com.google.android.gms.* modules.

You can probably see the root cause by running the build command with the --stacktrace parameter. i.e.:

./gradlew :app:dependencies --stacktrace

which might output the cause of the problem:

Caused by: org.gradle.api.GradleException: The library com.google.android.gms:play-services-measurement-base is being requested by various other libraries at [[15.0.2,15.0.2], [16.0.0,16.0.0]], but resolves to 16.0.0. Disable the plugin and check your dependencies tree using ./gradlew :app:dependencies. at com.google.gms.googleservices.GoogleServicesPlugin$1$_afterResolve_closure1.doCall(GoogleServicesPlugin.groovy:328) at org.gradle.api.internal.ClosureBackedAction.execute(ClosureBackedAction.java:71)

ant build.xml file doesn't exist

Please install at ubuntu openjdk-7-jdk

sudo apt-get install openjdk-7-jdk

on Windows try find find openjdk

Drop a temporary table if it exists

Check for the existence by retrieving its object_id:

if object_id('tempdb..##clients_keyword') is not null
    drop table ##clients_keyword

Search for a particular string in Oracle clob column

Below code can be used to search a particular string in Oracle clob column

select *  
from RLOS_BINARY_BP
where dbms_lob.instr(DED_ENQ_XML,'2003960067') > 0;

where RLOS_BINARY_BP is table name and DED_ENQ_XML is column name (with datatype as CLOB) of Oracle database.

C# DLL config file

It confusing to mock a "real" application configuration file. I suggest you roll your own because it is quite easy to parse an XML file using e.g. LINQ.

For example create an XML file MyDll.config like below and copy it alongside the DLL. To Keep it up to date set its property in Visual Studio to "Copy to Output Directory"

<?xml version="1.0" encoding="utf-8" ?>
 <configuration>
  <setting key="KeyboardEmulation" value="Off"></setting>
 </configuration>

In your Code read it like this:

    XDocument config = XDocument.Load("MyDll.config");
    var settings = config.Descendants("setting").Select(s => new { Key = s.Attribute("key").Value, Value = s.Attribute("value").Value });
    bool keyboardEmulation = settings.First(s => s.Key == "KeyboardEmulation").Value == "On";

In WPF, what are the differences between the x:Name and Name attributes?

There really is only one name in XAML, the x:Name. A framework, such as WPF, can optionally map one of its properties to XAML's x:Name by using the RuntimeNamePropertyAttribute on the class that designates one of the classes properties as mapping to the x:Name attribute of XAML.

The reason this was done was to allow for frameworks that already have a concept of "Name" at runtime, such as WPF. In WPF, for example, FrameworkElement introduces a Name property.

In general, a class does not need to store the name for x:Name to be useable. All x:Name means to XAML is generate a field to store the value in the code behind class. What the runtime does with that mapping is framework dependent.

So, why are there two ways to do the same thing? The simple answer is because there are two concepts mapped onto one property. WPF wants the name of an element preserved at runtime (which is usable through Bind, among other things) and XAML needs to know what elements you want to be accessible by fields in the code behind class. WPF ties these two together by marking the Name property as an alias of x:Name.

In the future, XAML will have more uses for x:Name, such as allowing you to set properties by referring to other objects by name, but in 3.5 and prior, it is only used to create fields.

Whether you should use one or the other is really a style question, not a technical one. I will leave that to others for a recommendation.

See also AutomationProperties.Name VS x:Name, AutomationProperties.Name is used by accessibility tools and some testing tools.

node.js, socket.io with SSL

check this.configuration..

app = module.exports = express();
var httpsOptions = { key: fs.readFileSync('certificates/server.key'), cert: fs.readFileSync('certificates/final.crt') };        
var secureServer = require('https').createServer(httpsOptions, app);
io = module.exports = require('socket.io').listen(secureServer,{pingTimeout: 7000, pingInterval: 10000});
io.set("transports", ["xhr-polling","websocket","polling", "htmlfile"]);
secureServer.listen(3000);

How to handle Uncaught (in promise) DOMException: The play() request was interrupted by a call to pause()

I second Shobhit Verma, and I have a little note to add : in his post he told that in Chrome (Opera for myself) the players need to be muted in order for the autoplay to succeed... And ironically, if you elevate the volume after load, it will still play... It's like all those anti-pop-ups mechanic that ignore invisible frame slid into your code... php-echoed html and javascript is : 10-second setTimeout onLoad of body tag that rises volume to maximum, video with autoplay and muted='muted' (yeah that $muted_code part is = "muted='muted")

echo "<body style='margin-bottom:0pt; margin-top:0pt; margin-left:0pt; margin-right:0pt' onLoad=\"setTimeout(function() {var vid = document.getElementById('hourglass_video'); vid.volume = 1.0;},10000);\">";
    echo "<div id='hourglass_container' width='100%' height='100%' align='center' style='text-align:right; vertical-align:bottom'>";
    echo "<video autoplay {$muted_code}title=\"!!! Pausing this video will immediately end your turn!!!\" oncontextmenu=\"dont_stop_hourglass(event);\" onPause=\"{$action}\" id='hourglass_video' frameborder='0' style='width:95%; margin-top:28%'>";

How do I print my Java object without getting "SomeType@2f92e0f4"?

If you Directly print any object of Person It will the ClassName@HashCode to the Code.

in your case com.foo.Person@2f92e0f4 is getting printed . Where Person is a class to which object belongs and 2f92e0f4 is hashCode of the Object.

public class Person {
  private String name;

  public Person(String name){
  this.name = name;
  }
  // getter/setter omitted

   @override
   public String toString(){
        return name;
   }
}

Now if you try to Use the object of Person then it will print the name

Class Test
 {
  public static void main(String... args){
    Person obj = new Person("YourName");
    System.out.println(obj.toString());
  }
}

Repeat a string in JavaScript a number of times

If you're not opposed to including a library in your project, lodash has a repeat function.

_.repeat('*', 3);
// ? '***

https://lodash.com/docs#repeat

How to list the files in current directory?

Maybe the dot notation for current folder is incorrect?

Print the result of File.getCanonicalFile() to check the path.

Can anyone explain to me why src isn't the current folder?

Your IDE is setting the class-path when invoking the JVM.

E.G. (reaches for Netbeans) If you select menus File | Project Properties (all classes) you might see something similar to:

Netbeans project options

It is the Working Directory that is of interest here.

What's the best way to parse a JSON response from the requests library?

You can use json.loads:

import json
import requests

response = requests.get(...)
json_data = json.loads(response.text)

This converts a given string into a dictionary which allows you to access your JSON data easily within your code.

Or you can use @Martijn's helpful suggestion, and the higher voted answer, response.json().

How to use jquery or ajax to update razor partial view in c#/asp.net for a MVC project

You can also use Url.Action for the path instead like so:

$.ajax({
        url: "@Url.Action("Holiday", "Calendar", new { area = "", year= (val * 1) + 1 })",                
        type: "GET",           
        success: function (partialViewResult) {            
            $("#refTable").html(partialViewResult);
        }
    });

What's the difference between getPath(), getAbsolutePath(), and getCanonicalPath() in Java?

Consider these filenames:

C:\temp\file.txt - This is a path, an absolute path, and a canonical path.

.\file.txt - This is a path. It's neither an absolute path nor a canonical path.

C:\temp\myapp\bin\..\\..\file.txt - This is a path and an absolute path. It's not a canonical path.

A canonical path is always an absolute path.

Converting from a path to a canonical path makes it absolute (usually tack on the current working directory so e.g. ./file.txt becomes c:/temp/file.txt). The canonical path of a file just "purifies" the path, removing and resolving stuff like ..\ and resolving symlinks (on unixes).

Also note the following example with nio.Paths:

String canonical_path_string = "C:\\Windows\\System32\\";
String absolute_path_string = "C:\\Windows\\System32\\drivers\\..\\";

System.out.println(Paths.get(canonical_path_string).getParent());
System.out.println(Paths.get(absolute_path_string).getParent());

While both paths refer to the same location, the output will be quite different:

C:\Windows
C:\Windows\System32\drivers

An existing connection was forcibly closed by the remote host - WCF

After pulling my hair out for like 6 hours of this completely useless error, my problem ended up being that my data transfer objects were too complex. Start with uber simple properties like public long Id { get; set;} that's it... nothing fancy.

Could not create work tree dir 'example.com'.: Permission denied

I was facing the same issue but it was not a permission issue.

When you are doing git clone it will create try to create replica of the respository structure.

When its trying to create the folder/directory with same name and path in your local os process is not allowing to do so and hence the error. There was "background" java process running in Task-manager which was accessing the resource of the directory(folder) and hence it was showing as permission denied for git operations. I have killed those process and that solved my problem. Cheers!!

Detect Scroll Up & Scroll down in ListView

try using the setOnScrollListener and implement the onScrollStateChanged with scrollState

setOnScrollListener(new OnScrollListener(){
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
      // TODO Auto-generated method stub
    }
    public void onScrollStateChanged(AbsListView view, int scrollState) {
      // TODO Auto-generated method stub
      final ListView lw = getListView();

       if(scrollState == 0) 
      Log.i("a", "scrolling stopped...");


        if (view.getId() == lw.getId()) {
        final int currentFirstVisibleItem = lw.getFirstVisiblePosition();
         if (currentFirstVisibleItem > mLastFirstVisibleItem) {
            mIsScrollingUp = false;
            Log.i("a", "scrolling down...");
        } else if (currentFirstVisibleItem < mLastFirstVisibleItem) {
            mIsScrollingUp = true;
            Log.i("a", "scrolling up...");
        }

        mLastFirstVisibleItem = currentFirstVisibleItem;
    } 
    }
  });

JavaScript - Replace all commas in a string

var mystring = "this,is,a,test"
mystring.replace(/,/g, "newchar");

Use the global(g) flag

Simple DEMO

Sum the digits of a number

The best way is to use math.
I knew this from school.(kinda also from codewars)

def digital_sum(num):
    return (num % 9) or num and 9

Just don't know how this works in code, but I know it's maths

If a number is divisible by 9 then, it's digital_sum will be 9,
if that's not the case then num % 9 will be the digital sum.

OWIN Startup Class Missing

It is also possible to get this exception (even when you have a correctly configured startup class) if running through IIS Express and your virtual directory is not configured correctly.

When I encountered this issue, the resolution was simply to press the 'Create Virtual Directory' button in the 'Web' tab of project properties (Using Visual Studio 2013)

Javascript: Unicode string to hex

Here is a tweak of McDowell's algorithm that doesn't pad the result:

  function toHex(str) {
    var result = '';
    for (var i=0; i<str.length; i++) {
      result += str.charCodeAt(i).toString(16);
    }
    return result;
  }

sort csv by column

To sort by MULTIPLE COLUMN (Sort by column_1, and then sort by column_2)

with open('unsorted.csv',newline='') as csvfile:
    spamreader = csv.DictReader(csvfile, delimiter=";")
    sortedlist = sorted(spamreader, key=lambda row:(row['column_1'],row['column_2']), reverse=False)


with open('sorted.csv', 'w') as f:
    fieldnames = ['column_1', 'column_2', column_3]
    writer = csv.DictWriter(f, fieldnames=fieldnames)
    writer.writeheader()
    for row in sortedlist:
        writer.writerow(row)

What is the difference between encrypting and signing in asymmetric encryption?

Yeah think of signing data as giving it your own wax stamp that nobody else has. It is done to achieve integrity and non-repudiation. Encryption is so no-one else can see the data. This is done to achieve confidentiality. See wikipedia http://en.wikipedia.org/wiki/Information_security#Key_concepts

A signature is a hash of your message signed using your private key.

Set icon for Android application

Place your images in drawables folder under either of the three and set it like this.

Code

<application android:icon="@drawable/your_icon" >
.... 
</application>  

How do I set the selected item in a comboBox to match my string using C#?

Assuming that your combobox isn't databound you would need to find the object's index in the "items" collection on your form and then set the "selectedindex" property to the appropriate index.

comboBox1.SelectedIndex = comboBox1.Items.IndexOf("test1");

Keep in mind that the IndexOf function may throw an argumentexception if the item isn't found.

How to print a int64_t type in C

//VC6.0 (386 & better)

    __int64 my_qw_var = 0x1234567890abcdef;

    __int32 v_dw_h;
    __int32 v_dw_l;

    __asm
        {
            mov eax,[dword ptr my_qw_var + 4]   //dwh
            mov [dword ptr v_dw_h],eax

            mov eax,[dword ptr my_qw_var]   //dwl
            mov [dword ptr v_dw_l],eax

        }
        //Oops 0.8 format
    printf("val = 0x%0.8x%0.8x\n", (__int32)v_dw_h, (__int32)v_dw_l);

Regards.

the easiest way to convert matrix to one row vector

You can use the function RESHAPE:

B = reshape(A.',1,[]);

How to capture UIView to UIImage without loss of quality on retina display

The currently accepted answer is now out of date, at least if you are supporting iOS 7.

Here is what you should be using if you are only supporting iOS7+:

+ (UIImage *) imageWithView:(UIView *)view
{
    UIGraphicsBeginImageContextWithOptions(view.bounds.size, view.opaque, 0.0f);
    [view drawViewHierarchyInRect:view.bounds afterScreenUpdates:NO];
    UIImage * snapshotImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return snapshotImage;
}

Swift 4:

func imageWithView(view: UIView) -> UIImage? {
    UIGraphicsBeginImageContextWithOptions(view.bounds.size, view.isOpaque, 0.0)
    defer { UIGraphicsEndImageContext() }
    view.drawHierarchy(in: view.bounds, afterScreenUpdates: true)
    return UIGraphicsGetImageFromCurrentImageContext()
}

As per this article, you can see that the new iOS7 method drawViewHierarchyInRect:afterScreenUpdates: is many times faster than renderInContext:. benchmark

PHP Array to CSV

It worked for me.

 $f=fopen('php://memory','w');
 $header=array("asdf ","asdf","asd","Calasdflee","Start Time","End Time" );      
 fputcsv($f,$header);
 fputcsv($f,$header);
 fputcsv($f,$header); 
 fseek($f,0);
 header('content-type:text/csv'); 
 header('Content-Disposition: attachment; filename="' . $filename . '";');
 fpassthru($f);```

Error in model.frame.default: variable lengths differ

Another thing that can cause this error is creating a model with the centering/scaling standardize function from the arm package -- m <- standardize(lm(y ~ x, data = train))

If you then try predict(m), you get the same error as in this question.

How to create a zip archive of a directory in Python?

To give more flexibility, e.g. select directory/file by name use:

import os
import zipfile

def zipall(ob, path, rel=""):
    basename = os.path.basename(path)
    if os.path.isdir(path):
        if rel == "":
            rel = basename
        ob.write(path, os.path.join(rel))
        for root, dirs, files in os.walk(path):
            for d in dirs:
                zipall(ob, os.path.join(root, d), os.path.join(rel, d))
            for f in files:
                ob.write(os.path.join(root, f), os.path.join(rel, f))
            break
    elif os.path.isfile(path):
        ob.write(path, os.path.join(rel, basename))
    else:
        pass

For a file tree:

.
+-- dir
¦   +-- dir2
¦   ¦   +-- file2.txt
¦   +-- dir3
¦   ¦   +-- file3.txt
¦   +-- file.txt
+-- dir4
¦   +-- dir5
¦   +-- file4.txt
+-- listdir.zip
+-- main.py
+-- root.txt
+-- selective.zip

You can e.g. select only dir4 and root.txt:

cwd = os.getcwd()
files = [os.path.join(cwd, f) for f in ['dir4', 'root.txt']]

with zipfile.ZipFile("selective.zip", "w" ) as myzip:
    for f in files:
        zipall(myzip, f)

Or just listdir in script invocation directory and add everything from there:

with zipfile.ZipFile("listdir.zip", "w" ) as myzip:
    for f in os.listdir():
        if f == "listdir.zip":
            # Creating a listdir.zip in the same directory
            # will include listdir.zip inside itself, beware of this
            continue
        zipall(myzip, f)

How do I create a chart with multiple series using different X values for each series?

You need to use the Scatter chart type instead of Line. That will allow you to define separate X values for each series.

convert string to date in sql server

if you datatype is datetime of the table.col , then database store data contain two partial : 1 (date) 2 (time)

Just in display data use convert or cast.

Example:

create table #test(part varchar(10),lastTime datetime)
go

insert into #test (part ,lastTime )
values('A','2012-11-05 ')

insert into #test (part ,lastTime )
values('B','2012-11-05 10:30')


go

select * from #test 

A   2012-11-05 00:00:00.000
B   2012-11-05 10:30:00.000

select part,CONVERT (varchar,lastTime,111) from #test

A   2012/11/05
B   2012/11/05

select part,CONVERT (varchar(10),lastTime,20) from #test 

A   2012-11-05
B   2012-11-05

Check if a number is a perfect square

This response doesn't pertain to your stated question, but to an implicit question I see in the code you posted, ie, "how to check if something is an integer?"

The first answer you'll generally get to that question is "Don't!" And it's true that in Python, typechecking is usually not the right thing to do.

For those rare exceptions, though, instead of looking for a decimal point in the string representation of the number, the thing to do is use the isinstance function:

>>> isinstance(5,int)
True
>>> isinstance(5.0,int)
False

Of course this applies to the variable rather than a value. If I wanted to determine whether the value was an integer, I'd do this:

>>> x=5.0
>>> round(x) == x
True

But as everyone else has covered in detail, there are floating-point issues to be considered in most non-toy examples of this kind of thing.

How to get class object's name as a string in Javascript?

Some time ago, I used this.

Perhaps you could try:

+function(){
    var my_var = function get_this_name(){
        alert("I " + this.init());
    };
    my_var.prototype.init = function(){
        return my_var.name;
    }
    new my_var();
}();

Pop an Alert: "I get_this_name".

SSH SCP Local file to Remote in Terminal Mac Os X

Just to clarify the answer given by JScoobyCed, the scp command cannot copy files to directories that require administrative permission. However, you can use the scp command to copy to directories that belong to the remote user.

So, to copy to a directory that requires root privileges, you must first copy that file to a directory belonging to the remote user using the scp command. Next, you must login to the remote account using ssh. Once logged in, you can then move the file to the directory of your choosing by using the sudo mv command. In short, the commands to use are as follows:

Using scp, copy file to a directory in the remote user's account, for example the Documents directory:

scp /path/to/your/local/file remoteUser@some_address:/home/remoteUser/Documents

Next, login to the remote user's account using ssh and then move the file to a restricted directory using sudo:

ssh remoteUser@some_address
sudo mv /home/remoteUser/Documents/file /var/www

Use a JSON array with objects with javascript

Your question feels a little incomplete, but I think what you're looking for is a way of making your JSON accessible to your code:

if you have the JSON string as above then you'd just need to do this

var jsonObj = eval('[{"id":28,"Title":"Sweden"}, {"id":56,"Title":"USA"}, {"id":89,"Title":"England"}]');

then you can access these vars with something like jsonObj[0].id etc

Let me know if that's not what you were getting at and I'll try to help.

M

Oracle: Call stored procedure inside the package

You're nearly there, just take out the EXECUTE:

DECLARE
  procId NUMBER;

BEGIN
  PKG1.INIT(1143824, 0, procId);
  DBMS_OUTPUT.PUT_LINE(procId);
END;

Why Would I Ever Need to Use C# Nested Classes

A nested class can have private, protected and protected internal access modifiers along with public and internal.

For example, you are implementing the GetEnumerator() method that returns an IEnumerator<T> object. The consumers wouldn't care about the actual type of the object. All they know about it is that it implements that interface. The class you want to return doesn't have any direct use. You can declare that class as a private nested class and return an instance of it (this is actually how the C# compiler implements iterators):

class MyUselessList : IEnumerable<int> {
    // ...
    private List<int> internalList;
    private class UselessListEnumerator : IEnumerator<int> {
        private MyUselessList obj;
        public UselessListEnumerator(MyUselessList o) {
           obj = o;
        }
        private int currentIndex = -1;
        public int Current {
           get { return obj.internalList[currentIndex]; }
        }
        public bool MoveNext() { 
           return ++currentIndex < obj.internalList.Count;
        }
    }
    public IEnumerator<int> GetEnumerator() {
        return new UselessListEnumerator(this);
    }
}

jQuery: How to get the event object in an event handler function without passing it as an argument?

If you call your event handler on markup, as you're doing now, you can't (x-browser). But if you bind the click event with jquery, it's possible the following way:

Markup:

  <a href="#" id="link1" >click</a>

Javascript:

  $(document).ready(function(){
      $("#link1").click(clickWithEvent);  //Bind the click event to the link
  });
  function clickWithEvent(evt){
     myFunc('p1', 'p2', 'p3');
     function myFunc(p1,p2,p3){  //Defined as local function, but has access to evt
        alert(evt.type);        
     }
  }

Since the event ob

`ui-router` $stateParams vs. $state.params

I have a root state which resolves sth. Passing $state as a resolve parameter won't guarantee the availability for $state.params. But using $stateParams will.

var rootState = {
    name: 'root',
    url: '/:stubCompanyId',
    abstract: true,
    ...
};

// case 1:
rootState.resolve = {
    authInit: ['AuthenticationService', '$state', function (AuthenticationService, $state) {
        console.log('rootState.resolve', $state.params);
        return AuthenticationService.init($state.params);
    }]
};
// output:
// rootState.resolve Object {}

// case 2:
rootState.resolve = {
    authInit: ['AuthenticationService', '$stateParams', function (AuthenticationService, $stateParams) {
        console.log('rootState.resolve', $stateParams);
        return AuthenticationService.init($stateParams);
    }]
};
// output:
// rootState.resolve Object {stubCompanyId:...}

Using "angular": "~1.4.0", "angular-ui-router": "~0.2.15"

Page loaded over HTTPS but requested an insecure XMLHttpRequest endpoint

I solved the problem adding a slash at the end of the requesting url

This way: '/data/180/' instead of: '/data/180'

Pythonic way to combine FOR loop and IF statement

You can use generator expressions like this:

gen = (x for x in xyz if x not in a)

for x in gen:
    print x

How do I create a comma delimited string from an ArrayList?

The solutions so far are all quite complicated. The idiomatic solution should doubtless be:

String.Join(",", x.Cast(Of String)().ToArray())

There's no need for fancy acrobatics in new framework versions. Supposing a not-so-modern version, the following would be easiest:

Console.WriteLine(String.Join(",", CType(x.ToArray(GetType(String)), String())))

mspmsp's second solution is a nice approach as well but it's not working because it misses the AddressOf keyword. Also, Convert.ToString is rather inefficient (lots of unnecessary internal evaluations) and the Convert class is generally not very cleanly designed. I tend to avoid it, especially since it's completely redundant.

How to make circular background using css?

You can use the :before and :after pseudo-classes to put a multi-layered background on a element.

#divID : before {
    background: url(someImage);
}

#div : after {
    background : url(someotherImage) -10% no-repeat;
}

Java optional parameters

Overloading is fine, but if there's a lot of variables that needs default value, you will end up with :

public void methodA(A arg1) {  }
public void methodA( B arg2,) {  }
public void methodA(C arg3) {  }
public void methodA(A arg1, B arg2) {  }
public void methodA(A arg1, C arg3) {  }
public void methodA( B arg2, C arg3) {  }
public void methodA(A arg1, B arg2, C arg3) {  }

So I would suggest use the Variable Argument provided by Java. Here's a link for explanation.

Difference between Destroy and Delete

When you invoke destroy or destroy_all on an ActiveRecord object, the ActiveRecord 'destruction' process is initiated, it analyzes the class you're deleting, it determines what it should do for dependencies, runs through validations, etc.

When you invoke delete or delete_all on an object, ActiveRecord merely tries to run the DELETE FROM tablename WHERE conditions query against the db, performing no other ActiveRecord-level tasks.

How do you easily create empty matrices javascript?

var matrix = [];
for(var i=0; i<9; i++) {
    matrix[i] = new Array(9);
}

... or:

var matrix = [];
for(var i=0; i<9; i++) {
    matrix[i] = [];
    for(var j=0; j<9; j++) {
        matrix[i][j] = undefined;
    }
}

Check if list contains element that contains a string and get that element

string result = myList.FirstOrDefault(x => x == myString)
if(result != null)
{
  //found
}

Where do I get servlet-api.jar from?

Grab it from here

Just choose required version and click 'Binary'. e.g direct link to version 2.5

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

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

How to change the button text of <input type="file" />?

Use <label> for the caption

<form enctype='multipart/form-data' action='/uploads.php' method=post>
<label for=b1>
    <u>Your</u> caption here
<input style='width:0px' type=file name=upfile id=b1
 onchange='optionalExtraProcessing(b1.files[0])'
 accept='image/png'>
</label>
</form>

This works without any javascript. You can decorate the label to any degree of complexity, to your heart's content. When you click on the label, the click automatically gets redirected to the file input. The file input itself can be made invisible by any method. If you want the label to appear like a button, there are many solutions, e.g.:

label u {
    -webkit-appearance: button;
    -moz-appearance: button;
    appearance: button;

    text-decoration: none;
    color: initial;
}

Should I always use a parallel stream when possible?

The Stream API was designed to make it easy to write computations in a way that was abstracted away from how they would be executed, making switching between sequential and parallel easy.

However, just because its easy, doesn't mean its always a good idea, and in fact, it is a bad idea to just drop .parallel() all over the place simply because you can.

First, note that parallelism offers no benefits other than the possibility of faster execution when more cores are available. A parallel execution will always involve more work than a sequential one, because in addition to solving the problem, it also has to perform dispatching and coordinating of sub-tasks. The hope is that you'll be able to get to the answer faster by breaking up the work across multiple processors; whether this actually happens depends on a lot of things, including the size of your data set, how much computation you are doing on each element, the nature of the computation (specifically, does the processing of one element interact with processing of others?), the number of processors available, and the number of other tasks competing for those processors.

Further, note that parallelism also often exposes nondeterminism in the computation that is often hidden by sequential implementations; sometimes this doesn't matter, or can be mitigated by constraining the operations involved (i.e., reduction operators must be stateless and associative.)

In reality, sometimes parallelism will speed up your computation, sometimes it will not, and sometimes it will even slow it down. It is best to develop first using sequential execution and then apply parallelism where

(A) you know that there's actually benefit to increased performance and

(B) that it will actually deliver increased performance.

(A) is a business problem, not a technical one. If you are a performance expert, you'll usually be able to look at the code and determine (B), but the smart path is to measure. (And, don't even bother until you're convinced of (A); if the code is fast enough, better to apply your brain cycles elsewhere.)

The simplest performance model for parallelism is the "NQ" model, where N is the number of elements, and Q is the computation per element. In general, you need the product NQ to exceed some threshold before you start getting a performance benefit. For a low-Q problem like "add up numbers from 1 to N", you will generally see a breakeven between N=1000 and N=10000. With higher-Q problems, you'll see breakevens at lower thresholds.

But the reality is quite complicated. So until you achieve experthood, first identify when sequential processing is actually costing you something, and then measure if parallelism will help.

Not Able To Debug App In Android Studio

This solved my problem. Uninstall app from device and run it again via Android studio.

Comparing strings in C# with OR in an if statement

try

if (testString.Equals(testString2)){
}

Convert a float64 to an int in Go

Simply casting to an int truncates the float, which if your system internally represent 2.0 as 1.9999999999, you will not get what you expect. The various printf conversions deal with this and properly round the number when converting. So to get a more accurate value, the conversion is even more complicated than you might first expect:

package main

import (
    "fmt"
    "strconv"
)

func main() {
    floats := []float64{1.9999, 2.0001, 2.0}
    for _, f := range floats {
        t := int(f)
        s := fmt.Sprintf("%.0f", f)
        if i, err := strconv.Atoi(s); err == nil {
            fmt.Println(f, t, i)
        } else {
            fmt.Println(f, t, err)
        }
    }
}

Code on Go Playground

Change the value in app.config file dynamically

 XmlReaderSettings _configsettings = new XmlReaderSettings();
 _configsettings.IgnoreComments = true;

 XmlReader _configreader = XmlReader.Create(ConfigFilePath, _configsettings);
 XmlDocument doc_config = new XmlDocument();
 doc_config.Load(_configreader);
 _configreader.Close();

 foreach (XmlNode RootName in doc_config.DocumentElement.ChildNodes)
 {
     if (RootName.LocalName == "appSettings")
     {
         if (RootName.HasChildNodes)
         {
             foreach (XmlNode _child in RootName.ChildNodes)
             {
                 if (_child.Attributes["key"].Value == "HostName")
                 {
                     if (_child.Attributes["value"].Value == "false")
                         _child.Attributes["value"].Value = "true";
                 }
             }
         }
     }
 }
 doc_config.Save(ConfigFilePath);

Remove spacing between table cells and rows

Nothing has worked. The solution for the issue is.

<style>
table td {
    padding: 0;
}
</style>

select from one table, insert into another table oracle sql query

try this query below:

Insert into tab1 (tab1.column1,tab1.column2) 
select tab2.column1, 'hard coded  value' 
from tab2 
where tab2.column='value';

How can I get the current time in C#?

DateTime.Now.ToString("HH:mm:ss tt");

this gives it to you as a string.

How to convert text to binary code in JavaScript?

Here's a pretty generic, native implementation, that I wrote some time ago,

// ABC - a generic, native JS (A)scii(B)inary(C)onverter.
// (c) 2013 Stephan Schmitz <[email protected]>
// License: MIT, http://eyecatchup.mit-license.org
// URL: https://gist.github.com/eyecatchup/6742657
var ABC = {
  toAscii: function(bin) {
    return bin.replace(/\s*[01]{8}\s*/g, function(bin) {
      return String.fromCharCode(parseInt(bin, 2))
    })
  },
  toBinary: function(str, spaceSeparatedOctets) {
    return str.replace(/[\s\S]/g, function(str) {
      str = ABC.zeroPad(str.charCodeAt().toString(2));
      return !1 == spaceSeparatedOctets ? str : str + " "
    })
  },
  zeroPad: function(num) {
    return "00000000".slice(String(num).length) + num
  }
};

and to be used as follows:

var binary1      = "01100110011001010110010101101100011010010110111001100111001000000110110001110101011000110110101101111001",
    binary2      = "01100110 01100101 01100101 01101100 01101001 01101110 01100111 00100000 01101100 01110101 01100011 01101011 01111001",
    binary1Ascii = ABC.toAscii(binary1),
    binary2Ascii = ABC.toAscii(binary2);

console.log("Binary 1:                   " + binary1);
console.log("Binary 1 to ASCII:          " + binary1Ascii);
console.log("Binary 2:                   " + binary2);
console.log("Binary 2 to ASCII:          " + binary2Ascii);
console.log("Ascii to Binary:            " + ABC.toBinary(binary1Ascii));     // default: space-separated octets
console.log("Ascii to Binary /wo spaces: " + ABC.toBinary(binary1Ascii, 0));  // 2nd parameter false to not space-separate octets

Source is on Github (gist): https://gist.github.com/eyecatchup/6742657

Hope it helps. Feel free to use for whatever you want (well, at least for whatever MIT permits).

Import a file from a subdirectory?

You can try inserting it in sys.path:

sys.path.insert(0, './lib')
import BoxTime

Error: class X is public should be declared in a file named X.java

I my case, I was using syncthing. It created a duplicate that I was not aware of and my compilation was failing.

Iterate through a C++ Vector using a 'for' loop

There's a couple of strong reasons to use iterators, some of which are mentioned here:

Switching containers later doesn't invalidate your code.

i.e., if you go from a std::vector to a std::list, or std::set, you can't use numerical indices to get at your contained value. Using an iterator is still valid.

Runtime catching of invalid iteration

If you modify your container in the middle of your loop, the next time you use your iterator it will throw an invalid iterator exception.

How to pass a Javascript Array via JQuery Post so that all its contents are accessible via the PHP $_POST array?

Here it goes an example:

$.post("test.php", { 'choices[]': ["Jon", "Susan"] });

Hope it helps.

Java - creating a new thread

run() method is called by start(). That happens automatically. You just need to call start(). For a complete tutorial on creating and calling threads see my blog http://preciselyconcise.com/java/concurrency/a_concurrency.php

open_basedir restriction in effect. File(/) is not within the allowed path(s):

The path you're refering to is incorect, and not withing the directoryRoot of your workspace. Try building an absolute path the the file you want to access, where you are now probably using a relative path...

How to disable input conditionally in vue.js

You can manipulate :disabled attribute in vue.js.

It will accept a boolean, if it's true, then the input gets disabled, otherwise it will be enabled...

Something like structured like below in your case for example:

<input type="text" id="name" class="form-control" name="name" v-model="form.name" :disabled="validated ? false : true">

Also read this below:

Conditionally Disabling Input Elements via JavaScript Expression

You can conditionally disable input elements inline with a JavaScript expression. This compact approach provides a quick way to apply simple conditional logic. For example, if you only needed to check the length of the password, you may consider doing something like this.

<h3>Change Your Password</h3>
<div class="form-group">
  <label for="newPassword">Please choose a new password</label>
  <input type="password" class="form-control" id="newPassword" placeholder="Password" v-model="newPassword">
</div>

<div class="form-group">
  <label for="confirmPassword">Please confirm your new password</label>
  <input type="password" class="form-control" id="confirmPassword" placeholder="Password" v-model="confirmPassword" v-bind:disabled="newPassword.length === 0 ? true : false">
</div>

How to check if a map contains a key in Go?

    var empty struct{}
    var ok bool
    var m map[string]struct{}
    m = make(map[string]struct{})
    m["somestring"] = empty


    _, ok = m["somestring"]
    fmt.Println("somestring exists?", ok) 
    _, ok = m["not"]
    fmt.Println("not exists?", ok)

Then, go run maps.go somestring exists? true not exists? false

Generate your own Error code in swift 3

I know you have already satisfied with an answer but if you are interested to know the right approach, then this might be helpful for you. I would prefer not to mix http-response error code with the error code in the error object (confused? please continue reading a bit...).

The http response codes are standard error codes about a http response defining generic situations when response is received and varies from 1xx to 5xx ( e.g 200 OK, 408 Request timed out,504 Gateway timeout etc - http://www.restapitutorial.com/httpstatuscodes.html )

The error code in a NSError object provides very specific identification to the kind of error the object describes for a particular domain of application/product/software. For example your application may use 1000 for "Sorry, You can't update this record more than once in a day" or say 1001 for "You need manager role to access this resource"... which are specific to your domain/application logic.

For a very small application, sometimes these two concepts are merged. But they are completely different as you can see and very important & helpful to design and work with large software.

So, there can be two techniques to handle the code in better way:

1. The completion callback will perform all the checks

completionHandler(data, httpResponse, responseError) 

2. Your method decides success and error situation and then invokes corresponding callback

if nil == responseError { 
   successCallback(data)
} else {
   failureCallback(data, responseError) // failure can have data also for standard REST request/response APIs
}

Happy coding :)

Using jquery to get all checked checkboxes with a certain class name

Simple way to get all of values into an array

var valores = (function () {
    var valor = [];
    $('input.className[type=checkbox]').each(function () {
        if (this.checked)
            valor.push($(this).val());
    });
    return valor;

})();

console.log(valores);

Differences between CHMOD 755 vs 750 permissions set

0755 = User:rwx Group:r-x World:r-x

0750 = User:rwx Group:r-x World:--- (i.e. World: no access)

r = read
w = write
x = execute (traverse for directories)

Laravel Query Builder where max id

No need to use sub query, just Try this,Its working fine:

  DB::table('orders')->orderBy('id', 'desc')->first();

Iterate over each line in a string in PHP

foreach(preg_split('~[\r\n]+~', $text) as $line){
    if(empty($line) or ctype_space($line)) continue; // skip only spaces
    // if(!strlen($line = trim($line))) continue; // or trim by force and skip empty
    // $line is trimmed and nice here so use it
}

^ this is how you break lines properly, cross-platform compatible with Regexp :)

Tomcat Server not starting with in 45 seconds

Nothing of the above helped me but setting:

-Djava.net.preferIPv4Stack=true

as VM Argument in the VM Arguments tab of the Tomcat Server Debug Configuration Settings solved the problem. (Tomcat 8, Windows 10, Eclipse Mars)

How can I get query parameters from a URL in Vue.js?

Another way (assuming you are using vue-router), is to map the query param to a prop in your router. Then you can treat it like any other prop in your component code. For example, add this route;

{ 
    path: '/mypage', 
    name: 'mypage', 
    component: MyPage, 
    props: (route) => ({ foo: route.query.foo })  
}

Then in your component you can add the prop as normal;

props: {
    foo: {
        type: String,
        default: null
    }
},

Then it will be available as this.foo and you can do anything you want with it (like set a watcher, etc.)

How to change an Eclipse default project into a Java project

  1. Right click on project
  2. Configure -> 'Convert to Faceted Form'
  3. You will get a popup, Select 'Java' in 'Project Facet' column.
  4. Press Apply and Ok.

What are passive event listeners?

Passive event listeners are an emerging web standard, new feature shipped in Chrome 51 that provide a major potential boost to scroll performance. Chrome Release Notes.

It enables developers to opt-in to better scroll performance by eliminating the need for scrolling to block on touch and wheel event listeners.

Problem: All modern browsers have a threaded scrolling feature to permit scrolling to run smoothly even when expensive JavaScript is running, but this optimization is partially defeated by the need to wait for the results of any touchstart and touchmove handlers, which may prevent the scroll entirely by calling preventDefault() on the event.

Solution: {passive: true}

By marking a touch or wheel listener as passive, the developer is promising the handler won't call preventDefault to disable scrolling. This frees the browser up to respond to scrolling immediately without waiting for JavaScript, thus ensuring a reliably smooth scrolling experience for the user.

document.addEventListener("touchstart", function(e) {
    console.log(e.defaultPrevented);  // will be false
    e.preventDefault();   // does nothing since the listener is passive
    console.log(e.defaultPrevented);  // still false
}, Modernizr.passiveeventlisteners ? {passive: true} : false);

DOM Spec , Demo Video , Explainer Doc

How to show a running progress bar while page is loading

Take a look here,

html file

<div class='progress' id="progress_div">
   <div class='bar' id='bar1'></div>
   <div class='percent' id='percent1'></div>
</div>

<div id="wrapper">
   <div id="content">
     <h1>Display Progress Bar While Page Loads Using jQuery<p>TalkersCode.com</p></h1>
   </div>
</div>

js file

document.onreadystatechange = function(e) {
  if (document.readyState == "interactive") {
    var all = document.getElementsByTagName("*");
    for (var i = 0, max = all.length; i < max; i++) {
      set_ele(all[i]);
    }
  }
}

function check_element(ele) {
  var all = document.getElementsByTagName("*");
  var totalele = all.length;
  var per_inc = 100 / all.length;

  if ($(ele).on()) {
    var prog_width = per_inc + Number(document.getElementById("progress_width").value);
    document.getElementById("progress_width").value = prog_width;
    $("#bar1").animate({
      width: prog_width + "%"
    }, 10, function() {
      if (document.getElementById("bar1").style.width == "100%") {
        $(".progress").fadeOut("slow");
      }
    });
  } else {
    set_ele(ele);
  }
}

function set_ele(set_element) {
  check_element(set_element);
}

it definitely solve your problem for complete tutorial here is the link http://talkerscode.com/webtricks/display-progress-bar-while-page-loads-using-jquery.php

YAML: Do I need quotes for strings in YAML?

After a brief review of the YAML cookbook cited in the question and some testing, here's my interpretation:

  • In general, you don't need quotes.
  • Use quotes to force a string, e.g. if your key or value is 10 but you want it to return a String and not a Fixnum, write '10' or "10".
  • Use quotes if your value includes special characters, (e.g. :, {, }, [, ], ,, &, *, #, ?, |, -, <, >, =, !, %, @, \).
  • Single quotes let you put almost any character in your string, and won't try to parse escape codes. '\n' would be returned as the string \n.
  • Double quotes parse escape codes. "\n" would be returned as a line feed character.
  • The exclamation mark introduces a method, e.g. !ruby/sym to return a Ruby symbol.

Seems to me that the best approach would be to not use quotes unless you have to, and then to use single quotes unless you specifically want to process escape codes.

Update

"Yes" and "No" should be enclosed in quotes (single or double) or else they will be interpreted as TrueClass and FalseClass values:

en:
  yesno:
    'yes': 'Yes'
    'no': 'No'

WebApi's {"message":"an error has occurred"} on IIS7, not in IIS Express

So i tried all the suggested solutions to no avail. All i did was to set run the app from the server and it displayed the error in full, this should have worked when i set customErrors mode to false but it didn't. The moment i browsed the API form the server i was able to see the problem.

Get records with max value for each group of grouped SQL results

Using ranking method.

SELECT @rn :=  CASE WHEN @prev_grp <> groupa THEN 1 ELSE @rn+1 END AS rn,  
   @prev_grp :=groupa,
   person,age,groupa  
FROM   users,(SELECT @rn := 0) r        
HAVING rn=1
ORDER  BY groupa,age DESC,person

This sql can be explained as below,

  1. select * from users, (select @rn := 0) r order by groupa, age desc, person

  2. @prev_grp is null

  3. @rn := CASE WHEN @prev_grp <> groupa THEN 1 ELSE @rn+1 END

    this is a three operator expression
    like this, rn = 1 if prev_grp != groupa else rn=rn+1

  4. having rn=1 filter out the row you need

Grep and Python

  1. use sys.argv to get the command-line parameters
  2. use open(), read() to manipulate file
  3. use the Python re module to match lines

Global Git ignore

Remember that running the command

git config --global core.excludesfile '~/.gitignore'

will just set up the global file, but will NOT create it. For Windows check your Users directory for the .gitconfig file, and edit it to your preferences. In my case It's like that:

[core]
  excludesfile = c:/Users/myuser/Dropbox/Apps/Git/.gitignore

Authenticate Jenkins CI for Github private repository

Jenkins creates a user Jenkins on the system. The ssh key must be generated for the Jenkins user. Here are the steps:

sudo su jenkins -s /bin/bash
cd ~
mkdir .ssh // may already exist
cd .ssh
ssh-keygen

Now you can create a Jenkins credential using the SSH key On Jenkins dashboard Add Credentials

select this option

Private Key: From the Jenkins master ~/.ssh

Is it fine to have foreign key as primary key?

Foreign keys are almost always "Allow Duplicates," which would make them unsuitable as Primary Keys.

Instead, find a field that uniquely identifies each record in the table, or add a new field (either an auto-incrementing integer or a GUID) to act as the primary key.

The only exception to this are tables with a one-to-one relationship, where the foreign key and primary key of the linked table are one and the same.

VMWare Player vs VMWare Workstation

VMWare Player can be seen as a free, closed-source competitor to Virtualbox.

Initially VMWare Player (up to version 2.5) was intended to operate on fixed virtual operating systems (e.g. play back pre-created virtual disks).

Many advanced features such as vsphere are probably not required by most users, and VMWare Player will provide the same core technologies and 3D acceleration as the ESX Workstation solution.

From my experience VMWare Player 5 is faster than Virtualbox 4.2 RC3 and has better SMP performance. Both are great however, each with its own unique advantages. Both are somewhat lacking in 2D rendering performance.

See the official FAQ, and a feature comparison table.

Print in new line, java

System.out.print(values[i] + " ");
//in one number be printed

Html.BeginForm and adding properties

I know this is old but you could create a custom extension if you needed to create that form over and over:

public static MvcForm BeginMultipartForm(this HtmlHelper htmlHelper)
{
    return htmlHelper.BeginForm(null, null, FormMethod.Post, 
     new Dictionary<string, object>() { { "enctype", "multipart/form-data" } });
}

Usage then just becomes

<% using(Html.BeginMultipartForm()) { %>

LIKE operator in LINQ

@adobrzyc had this great custom LIKE function - I just wanted to share the IEnumerable version of it.

public static class LinqEx
{
    private static readonly MethodInfo ContainsMethod = typeof(string).GetMethod("Contains");
    private static readonly MethodInfo StartsWithMethod = typeof(string).GetMethod("StartsWith", new[] { typeof(string) });
    private static readonly MethodInfo EndsWithMethod = typeof(string).GetMethod("EndsWith", new[] { typeof(string) });

    private static Func<TSource, bool> LikeExpression<TSource, TMember>(Expression<Func<TSource, TMember>> property, string value)
    {
        var param = Expression.Parameter(typeof(TSource), "t");
        var propertyInfo = GetPropertyInfo(property);
        var member = Expression.Property(param, propertyInfo.Name);

        var startWith = value.StartsWith("%");
        var endsWith = value.EndsWith("%");

        if (startWith)
            value = value.Remove(0, 1);

        if (endsWith)
            value = value.Remove(value.Length - 1, 1);

        var constant = Expression.Constant(value);
        Expression exp;

        if (endsWith && startWith)
        {
            exp = Expression.Call(member, ContainsMethod, constant);
        }
        else if (startWith)
        {
            exp = Expression.Call(member, EndsWithMethod, constant);
        }
        else if (endsWith)
        {
            exp = Expression.Call(member, StartsWithMethod, constant);
        }
        else
        {
            exp = Expression.Equal(member, constant);
        }

        return Expression.Lambda<Func<TSource, bool>>(exp, param).Compile();
    }

    public static IEnumerable<TSource> Like<TSource, TMember>(this IEnumerable<TSource> source, Expression<Func<TSource, TMember>> parameter, string value)
    {
        return source.Where(LikeExpression(parameter, value));
    }


    private static PropertyInfo GetPropertyInfo(Expression expression)
    {
        var lambda = expression as LambdaExpression;
        if (lambda == null)
            throw new ArgumentNullException("expression");

        MemberExpression memberExpr = null;

        switch (lambda.Body.NodeType)
        {
            case ExpressionType.Convert:
                memberExpr = ((UnaryExpression)lambda.Body).Operand as MemberExpression;
                break;
            case ExpressionType.MemberAccess:
                memberExpr = lambda.Body as MemberExpression;
                break;
        }

        if (memberExpr == null)
            throw new InvalidOperationException("Specified expression is invalid. Unable to determine property info from expression.");


        var output = memberExpr.Member as PropertyInfo;

        if (output == null)
            throw new InvalidOperationException("Specified expression is invalid. Unable to determine property info from expression.");

        return output;
    }
}

How can I check that two objects have the same set of property names?

If you want deep validation like @speculees, here's an answer using deep-keys (disclosure: I'm sort of a maintainer of this small package)

// obj1 should have all of obj2's properties
var deepKeys = require('deep-keys');
var _ = require('underscore');
assert(0 === _.difference(deepKeys(obj2), deepKeys(obj1)).length);

// obj1 should have exactly obj2's properties
var deepKeys = require('deep-keys');
var _ = require('lodash');
assert(0 === _.xor(deepKeys(obj2), deepKeys(obj1)).length);

or with chai:

var expect = require('chai').expect;
var deepKeys = require('deep-keys');
// obj1 should have all of obj2's properties
expect(deepKeys(obj1)).to.include.members(deepKeys(obj2));
// obj1 should have exactly obj2's properties
expect(deepKeys(obj1)).to.have.members(deepKeys(obj2));

Parsing JSON in Java without knowing JSON format

To get JSON quickly into Java objects (Maps) that you can then 'drill' and work with, you can use json-io (https://github.com/jdereg/json-io). This library will let you read in a JSON String, and get back a 'Map of Maps' representation.

If you have the corresponding Java classes in your JVM, you can read the JSON in and it will parse it directly into instances of the Java classes.

JsonReader.jsonToMaps(String json)

where json is the String containing the JSON to be read. The return value is a Map where the keys will contain the JSON fields, and the values will contain the associated values.

JsonReader.jsonToJava(String json) 

will read the same JSON string in, and the return value will be the Java instance that was serialized into the JSON. Use this API if you have the classes in your JVM that were written by

JsonWriter.objectToJson(MyClass foo).

How to copy a selection to the OS X clipboard

For Mac - Holding option key followed by ctrl V while selecting the text did the trick.

How to use fetch in typescript

If you take a look at @types/node-fetch you will see the body definition

export class Body {
    bodyUsed: boolean;
    body: NodeJS.ReadableStream;
    json(): Promise<any>;
    json<T>(): Promise<T>;
    text(): Promise<string>;
    buffer(): Promise<Buffer>;
}

That means that you could use generics in order to achieve what you want. I didn't test this code, but it would looks something like this:

import { Actor } from './models/actor';

fetch(`http://swapi.co/api/people/1/`)
      .then(res => res.json<Actor>())
      .then(res => {
          let b:Actor = res;
      });

How can javascript upload a blob?

2019 Update

This updates the answers with the latest Fetch API and doesn't need jQuery.

Disclaimer: doesn't work on IE, Opera Mini and older browsers. See caniuse.

Basic Fetch

It could be as simple as:

  fetch(`https://example.com/upload.php`, {method:"POST", body:blobData})
                .then(response => console.log(response.text()))

Fetch with Error Handling

After adding error handling, it could look like:

fetch(`https://example.com/upload.php`, {method:"POST", body:blobData})
            .then(response => {
                if (response.ok) return response;
                else throw Error(`Server returned ${response.status}: ${response.statusText}`)
            })
            .then(response => console.log(response.text()))
            .catch(err => {
                alert(err);
            });

PHP Code

This is the server-side code in upload.php.

<?php    
    // gets entire POST body
    $data = file_get_contents('php://input');
    // write the data out to the file
    $fp = fopen("path/to/file", "wb");

    fwrite($fp, $data);
    fclose($fp);
?>

how to make password textbox value visible when hover an icon

1 minute googling gave me this result. See the DEMO!

HTML

<form>
    <label for="username">Username:</label>
    <input id="username" name="username" type="text" placeholder="Username" />
    <label for="password">Password:</label>
    <input id="password" name="password" type="password" placeholder="Password" />
    <input id="submit" name="submit" type="submit" value="Login" />
</form>

jQuery

// ----- Setup: Add dummy text field for password and add toggle link to form; "offPage" class moves element off-screen
$('input[type=password]').each(function () {
    var el = $(this),
        elPH = el.attr("placeholder");
    el.addClass("offPage").after('<input class="passText" placeholder="' + elPH + '" type="text" />');
});
$('form').append('<small><a class="togglePassText" href="#">Toggle Password Visibility</a></small>');

// ----- keep password field and dummy text field in sync
$('input[type=password]').keyup(function () {
    var elText = $(this).val();
    $('.passText').val(elText);
});
$('.passText').keyup(function () {
    var elText = $(this).val();
    $('input[type=password]').val(elText);
});

// ----- Toggle link functionality - turn on/off "offPage" class on fields
$('a.togglePassText').click(function (e) {
    $('input[type=password], .passText').toggleClass("offPage");
    e.preventDefault(); // <-- prevent any default actions
});

CSS

.offPage {
    position: absolute;
    bottom: 100%;
    right: 100%;
}

How to detect if URL has changed after hash in JavaScript

I wanted to be able to add locationchange event listeners. After the modification below, we'll be able to do it, like this

window.addEventListener('locationchange', function(){
    console.log('location changed!');
})

In contrast, window.addEventListener('hashchange',()=>{}) would only fire if the part after a hashtag in a url changes, and window.addEventListener('popstate',()=>{}) doesn't always work.

This modification, similar to Christian's answer, modifies the history object to add some functionality.

By default, before these modifications, there's a popstate event, but there are no events for pushstate, and replacestate.

This modifies these three functions so that all fire a custom locationchange event for you to use, and also pushstate and replacestate events if you want to use those.

These are the modifications:

history.pushState = ( f => function pushState(){
    var ret = f.apply(this, arguments);
    window.dispatchEvent(new Event('pushstate'));
    window.dispatchEvent(new Event('locationchange'));
    return ret;
})(history.pushState);

history.replaceState = ( f => function replaceState(){
    var ret = f.apply(this, arguments);
    window.dispatchEvent(new Event('replacestate'));
    window.dispatchEvent(new Event('locationchange'));
    return ret;
})(history.replaceState);

window.addEventListener('popstate',()=>{
    window.dispatchEvent(new Event('locationchange'))
});

Note:

We're creating a closure, old = (f=>function new(){f();...})(old) replaces old with a new function that contains the previous old saved within it (old is not run at this moment, but it will be run inside of new)

How can I make a .NET Windows Forms application that only runs in the System Tray?

As mat1t says - you need to add a NotifyIcon to your application and then use something like the following code to set the tooltip and context menu:

this.notifyIcon.Text = "This is the tooltip";
this.notifyIcon.ContextMenu = new ContextMenu();
this.notifyIcon.ContextMenu.MenuItems.Add(new MenuItem("Option 1", new EventHandler(handler_method)));

This code shows the icon in the system tray only:

this.notifyIcon.Visible = true;  // Shows the notify icon in the system tray

The following will be needed if you have a form (for whatever reason):

this.ShowInTaskbar = false;  // Removes the application from the taskbar
Hide();

The right click to get the context menu is handled automatically, but if you want to do some action on a left click you'll need to add a Click handler:

    private void notifyIcon_Click(object sender, EventArgs e)
    {
        var eventArgs = e as MouseEventArgs;
        switch (eventArgs.Button)
        {
            // Left click to reactivate
            case MouseButtons.Left:
                // Do your stuff
                break;
        }
    }

Increase days to php current Date()

<?php
$dt = new DateTime;
if(isset($_GET['year']) && isset($_GET['week'])) {
    $dt->setISODate($_GET['year'], $_GET['week']);
} else {
    $dt->setISODate($dt->format('o'), $dt->format('W'));
}
$year = $dt->format('o');
$week = $dt->format('W');
?>

<a href="<?php echo $_SERVER['PHP_SELF'].'?week='.($week-1).'&year='.$year; ?>">Pre Week</a> 
<a href="<?php echo $_SERVER['PHP_SELF'].'?week='.($week+1).'&year='.$year; ?>">Next Week</a>
<table width="100%" style="height: 75px; border: 1px solid #00A2FF;">
<tr>
<td style="display: table-cell;
    vertical-align: middle;
    cursor: pointer;
    width: 75px;
    height: 75px;
    border: 4px solid #00A2FF;
    border-radius: 50%;">Employee</td>
<?php
do {
    echo "<td>" . $dt->format('M') . "<br>" . $dt->format('d M Y') . "</td>\n";
    $dt->modify('+1 day');
} while ($week == $dt->format('W'));
?>
</tr>
</table>

Failed to build gem native extension (installing Compass)

Try this, then try to install compass again

sudo apt install ruby-full

Finding rows containing a value (or values) in any column

Here's a dplyr option:

library(dplyr)

# across all columns:
df %>% filter_all(any_vars(. %in% c('M017', 'M018')))

# or in only select columns:
df %>% filter_at(vars(col1, col2), any_vars(. %in% c('M017', 'M018')))                                                                                                     

How do I parse a HTML page with Node.js

You can use the npm modules jsdom and htmlparser to create and parse a DOM in Node.JS.

Other options include:

  • BeautifulSoup for python
  • you can convert you html to xhtml and use XSLT
  • HTMLAgilityPack for .NET
  • CsQuery for .NET (my new favorite)
  • The spidermonkey and rhino JS engines have native E4X support. This may be useful, only if you convert your html to xhtml.

Out of all these options, I prefer using the Node.js option, because it uses the standard W3C DOM accessor methods and I can reuse code on both the client and server. I wish BeautifulSoup's methods were more similar to the W3C dom, and I think converting your HTML to XHTML to write XSLT is just plain sadistic.

Jquery $.ajax fails in IE on cross domain calls

Note, adding

$.support.cors = true;

was sufficient to force $.ajax calls to work on IE8

How to initialize struct?

Structure types should, whenever practical, either have all of their state encapsulated in public fields which may independently be set to any values which are valid for their respective type, or else behave as a single unified value which can only bet set via constructor, factory, method, or else by passing an instance of the struct as an explicit ref parameter to one of its public methods. Contrary to what some people claim, that there's nothing wrong with a struct having public fields, if it is supposed to represent a set of values which may sensibly be either manipulated individually or passed around as a group (e.g. the coordinates of a point). Historically, there have been problems with structures that had public property setters, and a desire to avoid public fields (implying that setters should be used instead) has led some people to suggest that mutable structures should be avoided altogether, but fields do not have the problems that properties had. Indeed, an exposed-field struct is the ideal representation for a loose collection of independent variables, since it is just a loose collection of variables.

In your particular example, however, it appears that the two fields of your struct are probably not supposed to be independent. There are three ways your struct could sensibly be designed:

  • You could have the only public field be the string, and then have a read-only "helper" property called length which would report its length if the string is non-null, or return zero if the string is null.

  • You could have the struct not expose any public fields, property setters, or mutating methods, and have the contents of the only field--a private string--be specified in the object's constructor. As above, length would be a property that would report the length of the stored string.

  • You could have the struct not expose any public fields, property setters, or mutating methods, and have two private fields: one for the string and one for the length, both of which would be set in a constructor that takes a string, stores it, measures its length, and stores that. Determining the length of a string is sufficiently fast that it probably wouldn't be worthwhile to compute and cache it, but it might be useful to have a structure that combined a string and its GetHashCode value.

It's important to be aware of a detail with regard to the third design, however: if non-threadsafe code causes one instance of the structure to be read while another thread is writing to it, that may cause the accidental creation of a struct instance whose field values are inconsistent. The resulting behaviors may be a little different from those that occur when classes are used in non-threadsafe fashion. Any code having anything to do with security must be careful not to assume that structure fields will be in a consistent state, since malicious code--even in a "full trust" enviroment--can easily generate structs whose state is inconsistent if that's what it wants to do.

PS -- If you wish to allow your structure to be initialized using an assignment from a string, I would suggest using an implicit conversion operator and making Length be a read-only property that returns the length of the underlying string if non-null, or zero if the string is null.

Modify SVG fill color when being served as Background-Image

You can store the SVG in a variable. Then manipulate the SVG string depending on your needs (i.e., set width, height, color, etc). Then use the result to set the background, e.g.

$circle-icon-svg: '<svg xmlns="http://www.w3.org/2000/svg"><circle cx="10" cy="10" r="10" /></svg>';

$icon-color: #f00;
$icon-color-hover: #00f;

@function str-replace($string, $search, $replace: '') {
    $index: str-index($string, $search);

    @if $index {
        @return str-slice($string, 1, $index - 1) + $replace + str-replace(str-slice($string, $index + str-length($search)), $search, $replace);
    }

    @return $string;
}

@function svg-fill ($svg, $color) {
  @return str-replace($svg, '<svg', '<svg fill="#{$color}"');
}

@function svg-size ($svg, $width, $height) {
  $svg: str-replace($svg, '<svg', '<svg width="#{$width}"');
  $svg: str-replace($svg, '<svg', '<svg height="#{$height}"');

  @return $svg;
}

.icon {
  $icon-svg: svg-size($circle-icon-svg, 20, 20);

  width: 20px; height: 20px; background: url('data:image/svg+xml;utf8,#{svg-fill($icon-svg, $icon-color)}');

  &:hover {
    background: url('data:image/svg+xml;utf8,#{svg-fill($icon-svg, $icon-color-hover)}');
  }
}

I have made a demo too, http://sassmeister.com/gist/4cf0265c5d0143a9e734.

This code makes a few assumptions about the SVG, e.g. that <svg /> element does not have an existing fill colour and that neither width or height properties are set. Since the input is hardcoded in the SCSS document, it is quite easy to enforce these constraints.

Do not worry about the code duplication. compression makes the difference negligible.

python - if not in list

You better do this syntax

if not (item in mylist):  
    Code inside the if

Importing Excel files into R, xlsx or xls

I have tried very hard on all the answers above. However, they did not actually help because I used a mac. The rio library has this import function which can basically import any type of data file into Rstudio, even those file using languages other than English!

Try codes below:

    library(rio)
    AB <- import("C:/AB_DNA_Tag_Numbers.xlsx")
    AB <- AB[,1]

Hope this help. For more detailed reference: https://cran.r-project.org/web/packages/rio/vignettes/rio.html

How to debug "ImagePullBackOff"?

You can use the 'describe pod' syntax

For OpenShift use:

oc describe pod <pod-id>  

For vanilla Kubernetes:

kubectl describe pod <pod-id>  

Examine the events of the output. In my case it shows Back-off pulling image coredns/coredns:latest

In this case the image coredns/coredns:latest can not be pulled from the Internet.

Events:
  FirstSeen LastSeen    Count   From                SubObjectPath           Type        Reason      Message
  --------- --------    -----   ----                -------------           --------    ------      -------
  5m        5m      1   {default-scheduler }                        Normal      Scheduled   Successfully assigned coredns-4224169331-9nhxj to 192.168.122.190
  5m        1m      4   {kubelet 192.168.122.190}   spec.containers{coredns}    Normal      Pulling     pulling image "coredns/coredns:latest"
  4m        26s     4   {kubelet 192.168.122.190}   spec.containers{coredns}    Warning     Failed      Failed to pull image "coredns/coredns:latest": Network timed out while trying to connect to https://index.docker.io/v1/repositories/coredns/coredns/images. You may want to check your internet connection or if you are behind a proxy.
  4m        26s     4   {kubelet 192.168.122.190}                   Warning     FailedSync  Error syncing pod, skipping: failed to "StartContainer" for "coredns" with ErrImagePull: "Network timed out while trying to connect to https://index.docker.io/v1/repositories/coredns/coredns/images. You may want to check your Internet connection or if you are behind a proxy."

  4m    2s  7   {kubelet 192.168.122.190}   spec.containers{coredns}    Normal  BackOff     Back-off pulling image "coredns/coredns:latest"
  4m    2s  7   {kubelet 192.168.122.190}                   Warning FailedSync  Error syncing pod, skipping: failed to "StartContainer" for "coredns" with ImagePullBackOff: "Back-off pulling image \"coredns/coredns:latest\""

Additional debuging steps

  1. try to pull the docker image and tag manually on your computer
  2. Identify the node by doing a 'kubectl/oc get pods -o wide'
  3. ssh into the node (if you can) that can not pull the docker image
  4. check that the node can resolve the DNS of the docker registry by performing a ping.
  5. try to pull the docker image manually on the node
  6. If you are using a private registry, check that your secret exists and the secret is correct. Your secret should also be in the same namespace. Thanks swenzel
  7. Some registries have firewalls that limit ip address access. The firewall may block the pull
  8. Some CIs create deployments with temporary docker secrets. So the secret expires after a few days (You are asking for production failures...)

Installing Python 2.7 on Windows 8

Easiest way is to open CMD or powershell as administrator and type

set PATH=%PATH%;C:\Python27

Change the selected value of a drop-down list with jQuery

Just an FYI, you don't need to use CSS classes to accomplish this.

You can write the following line of code to get the correct control name on the client:

$("#<%= statusDDL.ClientID %>").val("2");

ASP.NET will render the control ID correctly inside the jQuery.

Stashing only staged changes in git - is it possible?

Out of your comments to Mike Monkiewicz answer I suggest to use a simpler model: Use regular development branches, but use the squash option of the merge to get a single commit in your master branch:

git checkout -b bug1    # create the development branch
* hack hack hack *      # do some work
git commit
* hack hack hack *
git commit
* hack hack hack *
git commit
* hack hack hack *
git commit
git checkout master     # go back to the master branch
git merge --squash bug1 # merge the work back
git commit              # commit the merge (don't forget
                        #    to change the default commit message)
git branch -D bug1      # remove the development branch

The advantage of this procedure is that you can use the normal git work flow.

How can I add an item to a ListBox in C# and WinForms?

You have to create an item of type ListBoxItem and add that to the Items collection:

list.Items.add( new ListBoxItem("clan", "sifOsoba"));

get basic SQL Server table structure information

You could use these functions:

sp_help TableName
sp_helptext ProcedureName

How to return dictionary keys as a list in Python?

I can think of 2 ways in which we can extract the keys from the dictionary.

Method 1: - To get the keys using .keys() method and then convert it to list.

some_dict = {1: 'one', 2: 'two', 3: 'three'}
list_of_keys = list(some_dict.keys())
print(list_of_keys)
-->[1,2,3]

Method 2: - To create an empty list and then append keys to the list via a loop. You can get the values with this loop as well (use .keys() for just keys and .items() for both keys and values extraction)

list_of_keys = []
list_of_values = []
for key,val in some_dict.items():
    list_of_keys.append(key)
    list_of_values.append(val)

print(list_of_keys)
-->[1,2,3]

print(list_of_values)
-->['one','two','three']