Programs & Examples On #Ihttpmodule

How to get a list of current open windows/process with Java?

This is my code for a function that gets the tasks and gets their names, also adding them into a list to be accessed from a list. It creates temp files with the data, reads the files and gets the task name with the .exe suffix, and arranges the files to be deleted when the program has exited with System.exit(0), it also hides the processes being used to get the tasks and also java.exe so that the user can't accidentally kill the process that runs the program all together.

private static final DefaultListModel tasks = new DefaultListModel();

public static void getTasks()
{
    new Thread()
    {
        @Override
        public void run()
        {
            try 
            {
                File batchFile = File.createTempFile("batchFile", ".bat");
                File logFile = File.createTempFile("log", ".txt");
                String logFilePath = logFile.getAbsolutePath();
                try (PrintWriter fileCreator = new PrintWriter(batchFile)) 
                {
                    String[] linesToPrint = {"@echo off", "tasklist.exe >>" + logFilePath, "exit"};
                    for(String string:linesToPrint)
                    {
                        fileCreator.println(string);
                    }
                    fileCreator.close();
                }
                int task = Runtime.getRuntime().exec(batchFile.getAbsolutePath()).waitFor();
                if(task == 0)
                {
                    FileReader fileOpener = new FileReader(logFile);
                    try (BufferedReader reader = new BufferedReader(fileOpener))
                    {
                        String line;
                        while(true)
                        {
                            line = reader.readLine();
                            if(line != null)
                            {
                                if(line.endsWith("K"))
                                {
                                    if(line.contains(".exe"))
                                    {
                                        int index = line.lastIndexOf(".exe", line.length());
                                        String taskName = line.substring(0, index + 4);
                                        if(! taskName.equals("tasklist.exe") && ! taskName.equals("cmd.exe") && ! taskName.equals("java.exe"))
                                        {
                                            tasks.addElement(taskName);
                                        }
                                    }
                                }
                            }
                            else
                            {
                                reader.close();
                                break;
                            }
                        }
                    }
                }
                batchFile.deleteOnExit();
                logFile.deleteOnExit();
            } 
            catch (FileNotFoundException ex) 
            {
                Logger.getLogger(Functions.class.getName()).log(Level.SEVERE, null, ex);
            } 
            catch (IOException | InterruptedException ex) 
            {
                Logger.getLogger(Functions.class.getName()).log(Level.SEVERE, null, ex);
            }
            catch (NullPointerException ex)
            {
                // This stops errors from being thrown on an empty line
            }
        }
    }.start();
}

public static void killTask(String taskName)
{
    new Thread()
    {
        @Override
        public void run()
        {
            try 
            {
                Runtime.getRuntime().exec("taskkill.exe /IM " + taskName);
            } 
            catch (IOException ex) 
            {
                Logger.getLogger(Functions.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }.start();
}

Calculate the center point of multiple latitude/longitude coordinate pairs

Out of object in PHP. Given array of coordinate pairs, returns center.

/**
 * Calculate center of given coordinates
 * @param  array    $coordinates    Each array of coordinate pairs
 * @return array                    Center of coordinates
 */
function getCoordsCenter($coordinates) {    
    $lats = $lons = array();
    foreach ($coordinates as $key => $value) {
        array_push($lats, $value[0]);
        array_push($lons, $value[1]);
    }
    $minlat = min($lats);
    $maxlat = max($lats);
    $minlon = min($lons);
    $maxlon = max($lons);
    $lat = $maxlat - (($maxlat - $minlat) / 2);
    $lng = $maxlon - (($maxlon - $minlon) / 2);
    return array("lat" => $lat, "lon" => $lng);
}

Taken idea from #4

Create session factory in Hibernate 4

[quote from http://www.javabeat.net/session-factory-hibernate-4/]

There are many APIs deprecated in the hibernate core framework. One of the frustrating point at this time is, hibernate official documentation is not providing the clear instructions on how to use the new API and it stats that the documentation is in complete. Also each incremental version gets changes on some of the important API. One such thing is the new API for creating the session factory in Hibernate 4.3.0 on wards. In our earlier versions we have created the session factory as below:

SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();

The method buildSessionFactory is deprecated from the hibernate 4 release and it is replaced with the new API. If you are using the hibernate 4.3.0 and above, your code has to be:

Configuration configuration = new Configuration().configure();

StandardServiceRegistryBuilder builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties());

SessionFactory factory = configuration.buildSessionFactory(builder.build());

Class ServiceRegistryBuilder is replaced by StandardServiceRegistryBuilder from 4.3.0. It looks like there will be lot of changes in the 5.0 release. Still there is not much clarity on the deprecated APIs and the suitable alternatives to use. Every incremental release comes up with more deprecated API, they are in way of fine tuning the core framework for the release 5.0.

Lock, mutex, semaphore... what's the difference?

Supporting ownership, maximum number of processes share lock and the maximum number of allowed processes/threads in critical section are three major factors that determine the name/type of the concurrent object with general name of lock. Since the value of these factors are binary (have two states), we can summarize them in a 3*8 truth-like table.

  • X (Supports Ownership?): no(0) / yes(1)
  • Y (#sharing processes): > 1 (8) / 1
  • Z (#processes/threads in CA): > 1 (8) / 1

  X   Y   Z          Name
 --- --- --- ------------------------
  0   8   8   Semaphore              
  0   8   1   Binary Semaphore       
  0   1   8   SemaphoreSlim          
  0   1   1   Binary SemaphoreSlim(?)
  1   8   8   Recursive-Mutex(?)     
  1   8   1   Mutex                  
  1   1   8   N/A(?)                 
  1   1   1   Lock/Monitor           

Feel free to edit or expand this table, I've posted it as an ascii table to be editable:)

CSS3's border-radius property and border-collapse:collapse don't mix. How can I use border-radius to create a collapsed table with rounded corners?

Here is a way:

_x000D_
_x000D_
div {_x000D_
  ..._x000D_
  overflow: hidden;_x000D_
  border-radius: 14px;_x000D_
  transform: rotate(0deg);_x000D_
}_x000D_
table {_x000D_
  border-spacing: 0;_x000D_
}
_x000D_
<div>_x000D_
  <table></table>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Or

    div {
      ...
      overflow: hidden;
      border-radius: 14px;
      position: relative;
      z-index: 1;
    }


What does value & 0xff do in Java?

It sets result to the (unsigned) value resulting from putting the 8 bits of value in the lowest 8 bits of result.

The reason something like this is necessary is that byte is a signed type in Java. If you just wrote:

int result = value;

then result would end up with the value ff ff ff fe instead of 00 00 00 fe. A further subtlety is that the & is defined to operate only on int values1, so what happens is:

  1. value is promoted to an int (ff ff ff fe).
  2. 0xff is an int literal (00 00 00 ff).
  3. The & is applied to yield the desired value for result.

(The point is that conversion to int happens before the & operator is applied.)

1Well, not quite. The & operator works on long values as well, if either operand is a long. But not on byte. See the Java Language Specification, sections 15.22.1 and 5.6.2.

Firebug-like debugger for Google Chrome

Try this, it's called Firebug Lite and apparently works with the beta version of Chrome.

You can also find it at: https://chrome.google.com/extensions/

How to push both value and key into PHP array

Example array_merge()....

$array1 = array("color" => "red", 2, 4); $array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4); $result = array_merge($array1, $array2); print_r($result);

Array([color] => green,[0] => 2,[1] => 4,[2] => a,[3] => b,[shape] => trapezoid,[4] => 4,)

Spring profiles and testing

Can I recommend doing it this way, define your test like this:

@RunWith(SpringJUnit4ClassRunner.class)
@TestExecutionListeners({
    TestPreperationExecutionListener.class
    })
@Transactional
@ActiveProfiles(profiles = "localtest")
@ContextConfiguration
public class TestContext {

  @Test
  public void testContext(){

  }

  @Configuration
  @PropertySource("classpath:/myprops.properties")
  @ImportResource({"classpath:context.xml" })
  public static class MyContextConfiguration{

  }
}

with the following content in myprops.properties file:

spring.profiles.active=localtest

With this your second properties file should get resolved:

META-INF/spring/config_${spring.profiles.active}.properties

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

package lecture3;

import java.util.Scanner;

public class divisibleBy2and5 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("Enter an integer number:");
        Scanner input = new Scanner(System.in);
        int x;
        x = input.nextInt();
         if (x % 2==0){
             System.out.println("The integer number you entered is divisible by 2");
         }
         else{
             System.out.println("The integer number you entered is not divisible by 2");
             if(x % 5==0){
                 System.out.println("The integer number you entered is divisible by 5");
             } 
             else{
                 System.out.println("The interger number you entered is not divisible by 5");
             }
        }

    }
}

How to insert element as a first child?

parentElement.prepend(newFirstChild);

This is a new addition in (likely) ES7. It is now vanilla JS, probably due to the popularity in jQuery. It is currently available in Chrome, FF, and Opera. Transpilers should be able to handle it until it becomes available everywhere.

P.S. You can directly prepend strings

parentElement.prepend('This text!');

Links: developer.mozilla.org - Polyfill

How to check if an array element exists?

You can use the function array_key_exists to do that.

For example,

$a=array("a"=>"Dog","b"=>"Cat");
if (array_key_exists("a",$a))
  {
  echo "Key exists!";
  }
else
  {
  echo "Key does not exist!";
  }

PS : Example taken from here.

How do format a phone number as a String in Java?

I'd have thought you need to use a MessageFormat rather than DecimalFormat. That should be more flexible.

ReDim Preserve to a Multi-Dimensional Array in Visual Basic 6

As you correctly point out, one can ReDim Preserve only the last dimension of an array (ReDim Statement on MSDN):

If you use the Preserve keyword, you can resize only the last array dimension and you can't change the number of dimensions at all. For example, if your array has only one dimension, you can resize that dimension because it is the last and only dimension. However, if your array has two or more dimensions, you can change the size of only the last dimension and still preserve the contents of the array

Hence, the first issue to decide is whether 2-dimensional array is the best data structure for the job. Maybe, 1-dimensional array is a better fit as you need to do ReDim Preserve?

Another way is to use jagged array as per Pieter Geerkens's suggestion. There is no direct support for jagged arrays in VB6. One way to code "array of arrays" in VB6 is to declare an array of Variant and make each element an array of desired type (String in your case). Demo code is below.

Yet another option is to implement Preserve part on your own. For that you'll need to create a copy of data to be preserved and then fill redimensioned array with it.

Option Explicit

Public Sub TestMatrixResize()
    Const MAX_D1 As Long = 2
    Const MAX_D2 As Long = 3

    Dim arr() As Variant
    InitMatrix arr, MAX_D1, MAX_D2
    PrintMatrix "Original array:", arr

    ResizeMatrix arr, MAX_D1 + 1, MAX_D2 + 1
    PrintMatrix "Resized array:", arr
End Sub

Private Sub InitMatrix(a() As Variant, n As Long, m As Long)
    Dim i As Long, j As Long
    Dim StringArray() As String

    ReDim a(n)
    For i = 0 To n
        ReDim StringArray(m)
        For j = 0 To m
            StringArray(j) = i * (m + 1) + j
        Next j
        a(i) = StringArray
    Next i
End Sub

Private Sub PrintMatrix(heading As String, a() As Variant)
    Dim i As Long, j As Long
    Dim s As String

    Debug.Print heading
    For i = 0 To UBound(a)
        s = ""
        For j = 0 To UBound(a(i))
            s = s & a(i)(j) & "; "
        Next j
        Debug.Print s
    Next i
End Sub

Private Sub ResizeMatrix(a() As Variant, n As Long, m As Long)
    Dim i As Long
    Dim StringArray() As String

    ReDim Preserve a(n)
    For i = 0 To n - 1
        StringArray = a(i)
        ReDim Preserve StringArray(m)
        a(i) = StringArray
    Next i
    ReDim StringArray(m)
    a(n) = StringArray
End Sub

Python - List of unique dictionaries

The usual way to find just the common elements in a set is to use Python's set class. Just add all the elements to the set, then convert the set to a list, and bam the duplicates are gone.

The problem, of course, is that a set() can only contain hashable entries, and a dict is not hashable.

If I had this problem, my solution would be to convert each dict into a string that represents the dict, then add all the strings to a set() then read out the string values as a list() and convert back to dict.

A good representation of a dict in string form is JSON format. And Python has a built-in module for JSON (called json of course).

The remaining problem is that the elements in a dict are not ordered, and when Python converts the dict to a JSON string, you might get two JSON strings that represent equivalent dictionaries but are not identical strings. The easy solution is to pass the argument sort_keys=True when you call json.dumps().

EDIT: This solution was assuming that a given dict could have any part different. If we can assume that every dict with the same "id" value will match every other dict with the same "id" value, then this is overkill; @gnibbler's solution would be faster and easier.

EDIT: Now there is a comment from André Lima explicitly saying that if the ID is a duplicate, it's safe to assume that the whole dict is a duplicate. So this answer is overkill and I recommend @gnibbler's answer.

How to solve ERR_CONNECTION_REFUSED when trying to connect to localhost running IISExpress - Error 502 (Cannot debug from Visual Studio)?

I've just fixed this for my machine. Maybe it will work for some. Maybe not for others, but here is what worked for me.

In IIS, I had to add bindings for https to the default website (or, I suppose, the website you are running the app under).

enter image description here

Now my localhost works when debugging from Visual Studio.

Normal arguments vs. keyword arguments

Using Python 3 you can have both required and non-required keyword arguments:


Optional: (default value defined for param 'b')

def func1(a, *, b=42):
    ...
func1(value_for_a) # b is optional and will default to 42

Required (no default value defined for param 'b'):

def func2(a, *, b):
    ... 
func2(value_for_a, b=21) # b is set to 21 by the function call
func2(value_for_a) # ERROR: missing 1 required keyword-only argument: 'b'`

This can help in cases where you have many similar arguments next to each other especially if they are of the same type, in that case I prefer using named arguments or I create a custom class if arguments belong together.

ImportError: No module named 'pygame'

go to python/scripts folder, open a command window to this path, type the following:

C:\python34\scripts> python -m pip install pygame

To test it, open python IDE and type

import pygame

print (pygame.ver)

It worked for me...

jquery ui Dialog: cannot call methods on dialog prior to initialization

So you use this:

var theDialog = $("#divDialog").dialog(opt);
theDialog.dialog("open");

and if you open a MVC Partial View in Dialog, you can create in index a hidden button and JQUERY click event:

$("#YourButton").click(function()
{
   theDialog.dialog("open");
   OR
   theDialog.dialog("close");
});

then inside partial view html you call button trigger click like:

$("#YouButton").trigger("click")

see ya.

Cannot open output file, permission denied

In my case - I found a process called

cb_console_runner

I stopped this process and things were ok again.

What is RSS and VSZ in Linux memory management

I think much has already been said, about RSS vs VSZ. From an administrator/programmer/user perspective, when I design/code applications I am more concerned about the RSZ, (Resident memory), as and when you keep pulling more and more variables (heaped) you will see this value shooting up. Try a simple program to build malloc based space allocation in loop, and make sure you fill data in that malloc'd space. RSS keeps moving up. As far as VSZ is concerned, it's more of virtual memory mapping that linux does, and one of its core features derived out of conventional operating system concepts. The VSZ management is done by Virtual memory management of the kernel, for more info on VSZ, see Robert Love's description on mm_struct and vm_struct, which are part of basic task_struct data structure in kernel.

How do I use 'git reset --hard HEAD' to revert to a previous commit?

WARNING: git clean -f will remove untracked files, meaning they're gone for good since they aren't stored in the repository. Make sure you really want to remove all untracked files before doing this.


Try this and see git clean -f.

git reset --hard will not remove untracked files, where as git-clean will remove any files from the tracked root directory that are not under Git tracking.

Alternatively, as @Paul Betts said, you can do this (beware though - that removes all ignored files too)

  • git clean -df
  • git clean -xdf CAUTION! This will also delete ignored files

Setting the correct PATH for Eclipse

Like Abob said:

Eclipse doesn't consult the JAVA_HOME variable

You should specify where Eclipse should find your JDK in the file eclipse.ini. Specifically, the following parameter (note that it is 2 separate lines in the ini file):

-vm
C:\Java\JDK\1.8\bin\javaw.exe

or wherever your javaw.exe happens to be.

Note: The format of the ini file is very particular; make sure to consult https://wiki.eclipse.org/Eclipse.ini to ensure you get it exactly right.

Assigning default values to shell variables with a single command in bash

FWIW, you can provide an error message like so:

USERNAME=${1:?"Specify a username"}

This displays a message like this and exits with code 1:

./myscript.sh
./myscript.sh: line 2: 1: Specify a username

A more complete example of everything:

#!/bin/bash
ACTION=${1:?"Specify 'action' as argv[1]"}
DIRNAME=${2:-$PWD}
OUTPUT_DIR=${3:-${HOMEDIR:-"/tmp"}}

echo "$ACTION"
echo "$DIRNAME"
echo "$OUTPUT_DIR"

Output:

$ ./script.sh foo
foo
/path/to/pwd
/tmp

$ export HOMEDIR=/home/myuser
$ ./script.sh foo
foo
/path/to/pwd
/home/myuser
  • $ACTION takes the value of the first argument, and exits if empty
  • $DIRNAME is the 2nd argument, and defaults to the current directory
  • $OUTPUT_DIR is the 3rd argument, or $HOMEDIR (if defined), else, /tmp. This works on OS X, but I'm not positive that it's portable.

C++ Cout & Cin & System "Ambiguous"

This kind of thing doesn't just magically happen on its own; you changed something! In industry we use version control to make regular savepoints, so when something goes wrong we can trace back the specific changes we made that resulted in that problem.

Since you haven't done that here, we can only really guess. In Visual Studio, Intellisense (the technology that gives you auto-complete dropdowns and those squiggly red lines) works separately from the actual C++ compiler under the bonnet, and sometimes gets things a bit wrong.

In this case I'd ask why you're including both cstdlib and stdlib.h; you should only use one of them, and I recommend the former. They are basically the same header, a C header, but cstdlib puts them in the namespace std in order to "C++-ise" them. In theory, including both wouldn't conflict but, well, this is Microsoft we're talking about. Their C++ toolchain sometimes leaves something to be desired. Any time the Intellisense disagrees with the compiler has to be considered a bug, whichever way you look at it!

Anyway, your use of using namespace std (which I would recommend against, in future) means that std::system from cstdlib now conflicts with system from stdlib.h. I can't explain what's going on with std::cout and std::cin.

Try removing #include <stdlib.h> and see what happens.

If your program is building successfully then you don't need to worry too much about this, but I can imagine the false positives being annoying when you're working in your IDE.

Is it possible to return empty in react render function?

Slightly off-topic but if you ever needed a class-based component that never renders anything and you are happy to use some yet-to-be-standardised ES syntax, you might want to go:

render = () => null

This is basically an arrow method that currently requires the transform-class-properties Babel plugin. React will not let you define a component without the render function and this is the most concise form satisfying this requirement that I can think of.

I'm currently using this trick in a variant of ScrollToTop borrowed from the react-router documentation. In my case, there's only a single instance of the component and it doesn't render anything, so a short form of "render null" fits nice in there.

Return row of Data Frame based on value in a column - R

Based on the syntax provided

 Select * Where Amount = min(Amount)

You could do using:

 library(sqldf)

Using @Kara Woo's example df

  sqldf("select * from df where Amount in (select min(Amount) from df)")
  #Name Amount
 #1    B    120
 #2    E    120

Generate Java classes from .XSD files...?

Well best option is %java_home%\bin\xjc -p [your namespace] [xsd_file].xsd.

I also have a question if we have an option to do reverse engineering here. if yes can we generate xsd from pojo class?

ImageView in circular through xml

just use this simple code: First add dependency :

implementation 'de.hdodenhof:circleimageview:2.2.0'

then add in xml layout the following code:-

<de.hdodenhof.circleimageview.CircleImageView xmlns:app="http://schemas.android.com/apk/res-auto"
                                        android:id="@+id/Imgshaligram"
                                        android:layout_width="96dp"
                                        android:layout_height="96dp"
                                        android:src="@drawable/shaligram"
                                        app:civ_border_color="#d1b1b1"

                                        android:foregroundGravity="center"/>

adding line break

This worked for me:

foreach (var item in FirmNameList){
    if (FirmNames != "")
    {
        FirmNames += ",\r\n"
    }

    FirmNames += item;
}

Turn off constraints temporarily (MS SQL)

And, if you want to verify that you HAVEN'T broken your relationships and introduced orphans, once you have re-armed your checks, i.e.

ALTER TABLE foo CHECK CONSTRAINT ALL

or

ALTER TABLE foo CHECK CONSTRAINT FK_something

then you can run back in and do an update against any checked columns like so:

UPDATE myUpdatedTable SET someCol = someCol, fkCol = fkCol, etc = etc

And any errors at that point will be due to failure to meet constraints.

Generate random integers between 0 and 9

>>> import random
>>> random.randrange(10)
3
>>> random.randrange(10)
1

To get a list of ten samples:

>>> [random.randrange(10) for x in range(10)]
[9, 0, 4, 0, 5, 7, 4, 3, 6, 8]

How to store JSON object in SQLite database

An alternative could be to use the new JSON extension for SQLite. I've only just come across this myself: https://www.sqlite.org/json1.html This would allow you to perform a certain level of querying the stored JSON. If you used VARCHAR or TEXT to store a JSON string you would have no ability to query it. This is a great article showing its usage (in python) http://charlesleifer.com/blog/using-the-sqlite-json1-and-fts5-extensions-with-python/

How to check if one DateTime is greater than the other in C#

I'd like to demonstrate that if you convert to .Date that you don't need to worry about hours/mins/seconds etc:

    [Test]
    public void ConvertToDateWillHaveTwoDatesEqual()
    {
        DateTime d1 = new DateTime(2008, 1, 1);
        DateTime d2 = new DateTime(2008, 1, 2);
        Assert.IsTrue(d1 < d2);

        DateTime d3 = new DateTime(2008, 1, 1,7,0,0);
        DateTime d4 = new DateTime(2008, 1, 1,10,0,0);
        Assert.IsTrue(d3 < d4);
        Assert.IsFalse(d3.Date < d4.Date);
    }

Debug JavaScript in Eclipse

MyEclipse (eclipse based, subscription required) and Webclipse (an eclipse plug-in, currently free), from my company, Genuitec, have newly engineered (as of 2015) JavaScript debugging built in:

enter image description here

You can debug both generic web applications and Node.js files.

Disable future dates after today in Jquery Ui Datepicker

In my case, I have given this attribute to the input tag

data-date-start-date="0d" data-date-end-date="0d"

Best way to check if MySQL results returned in PHP?

mysqli_fetch_array() returns NULL if there is no row.

In procedural style:

if ( ! $row = mysqli_fetch_array( $result ) ) {
    ... no result ...
}
else {
    ... get the first result in $row ...
}

In Object oriented style:

if ( ! $row = $result->fetch_array() ) {
    ...
}
else {
    ... get the first result in $row ...
}

jQuery send HTML data through POST

_x000D_
_x000D_
jQuery.post(post_url,{ content: "John" } )_x000D_
 .done(function( data ) {_x000D_
   _x000D_
   _x000D_
 });_x000D_
 
_x000D_
_x000D_
_x000D_

I used the technique what u have replied above, it works fine but my problem is i need to generate a pdf conent using john as text . I have been able to echo the passed data. but getting empty in when generating pdf uisng below content ples check

_x000D_
_x000D_
ob_start();_x000D_
        _x000D_
   include_once(JPATH_SITE .'/components/com_gaevents/pdfgenerator.php');_x000D_
   $content = ob_get_clean();_x000D_
   _x000D_
  _x000D_
  _x000D_
    $test = $_SESSION['content'] ;_x000D_
  _x000D_
   require_once(JPATH_SITE.'/html2pdf/html2pdf.class.php');_x000D_
            $html2pdf = new HTML2PDF('P', 'A4', 'en', true, 'UTF-8',0 );   _x000D_
    $html2pdf->setDefaultFont('Arial');_x000D_
    $html2pdf->WriteHTML($test);
_x000D_
_x000D_
_x000D_

Resetting a multi-stage form with jQuery

Complementing the accepted answer, if you use SELECT2 plugin, you need to recall select2 script to make changes is all select2 fields:

function resetForm(formId){
        $('#'+formId).find('input:text, input:password, input:file, select, select2, textarea').val('');
        $('#'+formId).find('input:radio, input:checkbox').removeAttr('checked').removeAttr('selected');
        $('.select2').select2();
    }

Liquibase lock - reasons?

In postgres 12 I needed to use this command:

UPDATE DATABASECHANGELOGLOCK SET LOCKED=false, LOCKGRANTED=null, LOCKEDBY=null where ID=1;

Html.DropdownListFor selected value not being set

public byte UserType
public string SelectUserType

You need to get one and set different one. Selected value can not be the same item that you are about to set.

@Html.DropDownListFor(p => p.SelectUserType, new SelectList(~~UserTypeNames, "Key", "Value",UserType))

I use Enum dictionary for my list, that's why there is "key", "value" pair.

How to extract numbers from a string and get an array of ints?

Pattern p = Pattern.compile("-?\\d+");
Matcher m = p.matcher("There are more than -2 and less than 12 numbers here");
while (m.find()) {
  System.out.println(m.group());
}

... prints -2 and 12.


-? matches a leading negative sign -- optionally. \d matches a digit, and we need to write \ as \\ in a Java String though. So, \d+ matches 1 or more digits.

How to document Python code using Doxygen

An other very good documentation tool is sphinx. It will be used for the upcoming python 2.6 documentation and is used by django and a lot of other python projects.

From the sphinx website:

  • Output formats: HTML (including Windows HTML Help) and LaTeX, for printable PDF versions
  • Extensive cross-references: semantic markup and automatic links for functions, classes, glossary terms and similar pieces of information
  • Hierarchical structure: easy definition of a document tree, with automatic links to siblings, parents and children
  • Automatic indices: general index as well as a module index
  • Code handling: automatic highlighting using the Pygments highlighter
  • Extensions: automatic testing of code snippets, inclusion of docstrings from Python modules, and more

How to get the python.exe location programmatically?

This works in Linux & Windows:

Python 3.x

>>> import sys
>>> print(sys.executable)
C:\path\to\python.exe

Python 2.x

>>> import sys
>>> print sys.executable
/usr/bin/python

Exclude property from type

With typescript 2.8, you can use the new built-in Exclude type. The 2.8 release notes actually mention this in the section "Predefined conditional types":

Note: The Exclude type is a proper implementation of the Diff type suggested here. [...] We did not include the Omit type because it is trivially written as Pick<T, Exclude<keyof T, K>>.

Applying this to your example, type XY could be defined as:

type XY = Pick<XYZ, Exclude<keyof XYZ, "z">>

Access denied for root user in MySQL command-line

Gain access to a MariaDB 10 database server

After stopping the database server, the next step is to gain access to the server through a backdoor by starting the database server and skipping networking and permission tables. This can be done by running the commands below.

sudo mysqld_safe --skip-grant-tables --skip-networking &

Reset MariaDB root Password

Now that the database server is started in safe mode, run the commands below to logon as root without password prompt. To do that, run the commands below

sudo mysql -u root

Then run the commands below to use the mysql database.

use mysql;

Finally, run the commands below to reset the root password.

update user set password=PASSWORD("new_password_here") where User='root';

Replace new_password _here with the new password you want to create for the root account, then press Enter.

After that, run the commands below to update the permissions and save your changes to disk.

flush privileges;

Exit (CTRL + D) and you’re done.

Next start MariaDB normally and test the new password you just created.

sudo systemctl stop mariadb.service
sudo systemctl start mariadb.service

Logon to the database by running the commands below.

sudo mysql -u root -p

source: https://websiteforstudents.com/reset-mariadb-root-password-ubuntu-17-04-17-10/

Plugin with id 'com.google.gms.google-services' not found

In the app build.gradle dependency, you must add the following code

classpath 'com.google.gms:google-services:$last_version'

And then please check the Google Play Service SDK tools installing status.

Different ways of adding to Dictionary

To insert the Value into the Dictionary

 Dictionary<string, string> dDS1 = new Dictionary<string, string>();//Declaration
 dDS1.Add("VEqpt", "aaaa");//adding key and value into the dictionary
 string Count = dDS1["VEqpt"];//assigning the value of dictionary key to Count variable
 dDS1["VEqpt"] = Count + "bbbb";//assigning the value to key

referenced before assignment error in python

I think you are using 'global' incorrectly. See Python reference. You should declare variable without global and then inside the function when you want to access global variable you declare it global yourvar.

#!/usr/bin/python

total

def checkTotal():
    global total
    total = 0

See this example:

#!/usr/bin/env python

total = 0

def doA():
    # not accessing global total
    total = 10

def doB():
    global total
    total = total + 1

def checkTotal():
    # global total - not required as global is required
    # only for assignment - thanks for comment Greg
    print total

def main():
    doA()
    doB()
    checkTotal()

if __name__ == '__main__':
    main()

Because doA() does not modify the global total the output is 1 not 11.

What is the difference between a static and const variable?

Static Variables:

  • Initialized only once.
  • Static variables are for the class (not per object). i.e memory is allocated only once per class and every instance uses it. So if one object modifies its value then the modified value is visible to other objects as well. ( A simple thought.. To know the number of objects created for a class we can put a static variable and do ++ in constructor)
  • Value persists between different function calls

Const Variables:

  • Const variables are a promise that you are not going to change its value anywhere in the program. If you do it, it will complain.

How to send HTTP request in java?

From Oracle's java tutorial

import java.net.*;
import java.io.*;

public class URLConnectionReader {
    public static void main(String[] args) throws Exception {
        URL yahoo = new URL("http://www.yahoo.com/");
        URLConnection yc = yahoo.openConnection();
        BufferedReader in = new BufferedReader(
                                new InputStreamReader(
                                yc.getInputStream()));
        String inputLine;

        while ((inputLine = in.readLine()) != null) 
            System.out.println(inputLine);
        in.close();
    }
}

How do I manage conflicts with git submodules?

Got help from this discussion. In my case the

git reset HEAD subby
git commit

worked for me :)

Rails Active Record find(:all, :order => ) issue

Make sure to check the schema at the database level directly. I've gotten burned by this before, where, for example, a migration was initially written to create a :datetime column, and I ran it locally, then tweaked the migration to a :date before actually deploying. Thus everyone's database looks good except for mine, and the bugs are subtle.

Create Generic method constraining T to an Enum

I always liked this (you could modify as appropriate):

public static IEnumerable<TEnum> GetEnumValues()
{
  Type enumType = typeof(TEnum);

  if(!enumType.IsEnum)
    throw new ArgumentException("Type argument must be Enum type");

  Array enumValues = Enum.GetValues(enumType);
  return enumValues.Cast<TEnum>();
}

How to create json by JavaScript for loop?

If I want to create JavaScript Object from string generated by for loop then I would JSON to Object approach. I would generate JSON string by iterating for loop and then use any popular JavaScript Framework to evaluate JSON to Object.

I have used Prototype JavaScript Framework. I have two array with keys and values. I iterate through for loop and generate valid JSON string. I use evalJSON() function to convert JSON string to JavaScript object.

Here is example code. Tryout on your FireBug Console

var key = ["color", "size", "fabric"];
var value = ["Black", "XL", "Cotton"];

var json = "{ ";
for(var i = 0; i < key.length; i++) {
    (i + 1) == key.length ? json += "\"" + key[i] + "\" : \"" + value[i] + "\"" : json += "\"" + key[i] + "\" : \"" + value[i] + "\",";
}
json += " }";
var obj = json.evalJSON(true);
console.log(obj);

How to disable Paste (Ctrl+V) with jQuery?

_x000D_
_x000D_
$(document).ready(function(){_x000D_
   $('input').on("cut copy paste",function(e) {_x000D_
      e.preventDefault();_x000D_
   });_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<input type="text" />
_x000D_
_x000D_
_x000D_

How to get an object's property's value by property name?

Try this :

$obj = @{
    SomeProp = "Hello"
}

Write-Host "Property Value is $($obj."SomeProp")"

Windows could not start the SQL Server (MSSQLSERVER) on Local Computer... (error code 3417)

This usually occurs when the master.mdf or the mastlog.ldf gets corrupt . In order to solve the issue goto the following path C:\Program Files\Microsoft SQL Server\MSSQL10.SQLEXPRESS\MSSQL , there you will find a folder ” Template Data ” , copy the master.mdf and mastlog.ldf and replace it in C:\Program Files\Microsoft SQL Server\MSSQL10.SQLEXPRESS\MSSQL\Data folder . Thats it . Now start the MS SQL service and you are done

The import javax.persistence cannot be resolved

My solution was to select the maven profiles I had defined in my pom.xml in which I had declared the hibernate dependencies.

CTRL + ALT + P in eclipse.

In my project I was experiencing this problem and many others because in my pom I have different profiles for supporting Glassfish 3, Glassfish 4 and also WildFly so I have differet versions of Hibernate per container as well as different Java compilation targets and so on. Selecting the active maven profiles resolved my issue.

Math.random() explanation

int randomWithRange(int min, int max)
{
   int range = (max - min) + 1;     
   return (int)(Math.random() * range) + min;
}

Output of randomWithRange(2, 5) 10 times:

5
2
3
3
2
4
4
4
5
4

The bounds are inclusive, ie [2,5], and min must be less than max in the above example.

EDIT: If someone was going to try and be stupid and reverse min and max, you could change the code to:

int randomWithRange(int min, int max)
{
   int range = Math.abs(max - min) + 1;     
   return (int)(Math.random() * range) + (min <= max ? min : max);
}

EDIT2: For your question about doubles, it's just:

double randomWithRange(double min, double max)
{
   double range = (max - min);     
   return (Math.random() * range) + min;
}

And again if you want to idiot-proof it it's just:

double randomWithRange(double min, double max)
{
   double range = Math.abs(max - min);     
   return (Math.random() * range) + (min <= max ? min : max);
}

mysqli_real_connect(): (HY000/2002): No such file or directory

First of all, make sure the mysql service is running:

ps elf|grep mysql

you will see an output like this if is running:

4 S root      9642     1  0  80   0 -  2859 do_wai 23:08 pts/0    00:00:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --pid-file=/var/lib/mysql/tomcat-machine.local.pid
4 S mysql     9716  9642  0  80   0 - 200986 poll_s 23:08 pts/0   00:00:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --user=mysql --log-error=/var/lib/mysql/tomcat-machine.local.err --pid-file=/var/lib/mysql/tomcat-machine.local.pid

then change localhost to 127.0.0.1 in config.inc.php

$cfg['Servers'][$i]['host'] = '127.0.0.1';

The default password for "root" user is empty "" do not type anything for the password

If it does not allow empty password you need to edit config.inc.php again and change:

$cfg['Servers'][$i]['AllowNoPassword'] = true;

The problem is a combination of config settings and MySQL not running. This was what helped me to fix this error.

Java regex to extract text between tags

    final Pattern pattern = Pattern.compile("tag\\](.+?)\\[/tag");
    final Matcher matcher = pattern.matcher("[tag]String I want to extract[/tag]");
    matcher.find();
    System.out.println(matcher.group(1));

Rolling back local and remote git repository by 1 commit

If nobody has pulled your remote repo yet, you can change your branch HEAD and force push it to said remote repo:

git reset --hard HEAD^ 
git push -f 

(or, if you have direct access to the remote repo, you can change its HEAD reference even though it is a bare repo)

Note, as commented by alien-technology in the comments below, on Windows (CMD session), you would need ^^:

git reset --hard HEAD^^
git push -f 

Update since 2011:
Using git push --force-with-lease (that I present here, introduced in 2013 with Git 1.8.5) is safer.

See Schwern's answer for illustration.


What if somebody has already pulled the repo? What would I do then?

Then I would suggest something that doesn't rewrite the history:

  • git revert locally your last commit (creating a new commit that reverses what the previous commit did)
  • push the 'revert' generated by git revert.

Removing space from dataframe columns in pandas

  • To remove white spaces:

1) To remove white space everywhere:

df.columns = df.columns.str.replace(' ', '')

2) To remove white space at the beginning of string:

df.columns = df.columns.str.lstrip()

3) To remove white space at the end of string:

df.columns = df.columns.str.rstrip()

4) To remove white space at both ends:

df.columns = df.columns.str.strip()
  • To replace white spaces with other characters (underscore for instance):

5) To replace white space everywhere

df.columns = df.columns.str.replace(' ', '_')

6) To replace white space at the beginning:

df.columns = df.columns.str.replace('^ +', '_')

7) To replace white space at the end:

df.columns = df.columns.str.replace(' +$', '_')

8) To replace white space at both ends:

df.columns = df.columns.str.replace('^ +| +$', '_')

All above applies to a specific column as well, assume you have a column named col, then just do:

df[col] = df[col].str.strip()  # or .replace as above

Using the star sign in grep

'*' works as a modifier for the previous item. So 'abc*def' searches for 'ab' followed by 0 or more 'c's follwed by 'def'.

What you probably want is 'abc.*def' which searches for 'abc' followed by any number of characters, follwed by 'def'.

How to add a where clause in a MySQL Insert statement?

Try this:

Update users
Set username = 'Jack', password='123'
Where ID = '1'

Or if you're actually trying to insert:

Insert Into users (id, username, password) VALUES ('1', 'Jack','123');

What is the default access specifier in Java?

Here is a quote about package level visibility from an interview with James Gosling, the creator of Java:

Bill Venners: Java has four access levels. The default is package. I have always wondered if making package access default was convenient because the three keywords that people from C++ already knew about were private, protected, and public. Or if you had some particular reason that you felt package access should be the default.

James Gosling: A package is generally a set of things that are kind of written together. So generically I could have done one of two things. One was force you always to put in a keyword that gives you the domain. Or I could have had a default value. And then the question is, what makes a sensible default? And I tend to go for what is the least dangerous thing.

So public would have been a really bad thing to make the default. Private would probably have been a bad thing to make a default, if only because people actually don't write private methods that often. And same thing with protected. And in looking at a bunch of code that I had, I decided that the most common thing that was reasonably safe was in the package. And C++ didn't have a keyword for that, because they didn't have a notion of packages.

But I liked it rather than the friends notion, because with friends you kind of have to enumerate who all of your friends are, and so if you add a new class to a package, then you generally end up having to go to all of the classes in that package and update their friends, which I had always found to be a complete pain in the butt.

But the friends list itself causes sort of a versioning problem. And so there was this notion of a friendly class. And the nice thing that I was making that the default -- I'll solve the problem so what should the keyword be?

For a while there actually was a friendly keyword. But because all the others start with "P," it was "phriendly" with a "PH." But that was only in there for maybe a day.

http://www.artima.com/intv/gosling2P.html

How to match, but not capture, part of a regex?

The only way not to capture something is using look-around assertions:

(?<=123-)((apple|banana)(?=-456)|(?=456))

Because even with non-capturing groups (?:…) the whole regular expression captures their matched contents. But this regular expression matches only apple or banana if it’s preceded by 123- and followed by -456, or it matches the empty string if it’s preceded by 123- and followed by 456.

|Lookaround  |    Name      |        What it Does                       |
-----------------------------------------------------------------------
|(?=foo)     |   Lookahead  | Asserts that what immediately FOLLOWS the |
|            |              |  current position in the string is foo    |
-------------------------------------------------------------------------
|(?<=foo)    |   Lookbehind | Asserts that what immediately PRECEDES the|
|            |              |  current position in the string is foo    |
-------------------------------------------------------------------------
|(?!foo)     |   Negative   | Asserts that what immediately FOLLOWS the |
|            |   Lookahead  |  current position in the string is NOT foo|
-------------------------------------------------------------------------
|(?<!foo)    |   Negative   | Asserts that what immediately PRECEDES the|
|            |   Lookbehind |  current position in the string is NOT foo|
-------------------------------------------------------------------------

How can I remove a style added with .css() function?

The accepted answer works but leaves an empty style attribute on the DOM in my tests. No big deal, but this removes it all:

removeAttr( 'style' );

This assumes you want to remove all dynamic styling and return back to the stylesheet styling.

Why is an OPTIONS request sent and can I disable it?

For a developer who understands the reason it exists but needs to access an API that doesn't handle OPTIONS calls without auth, I need a temporary answer so I can develop locally until the API owner adds proper SPA CORS support or I get a proxy API up and running.

I found you can disable CORS in Safari and Chrome on a Mac.

Disable same origin policy in Chrome

Chrome: Quit Chrome, open an terminal and paste this command: open /Applications/Google\ Chrome.app --args --disable-web-security --user-data-dir

Safari: Disabling same-origin policy in Safari

If you want to disable the same-origin policy on Safari (I have 9.1.1), then you only need to enable the developer menu, and select "Disable Cross-Origin Restrictions" from the develop menu.

How do you write a migration to rename an ActiveRecord model and its table in Rails?

You can do execute this command : rails g migration rename_{old_table_name}to{new_table_name}

after you edit the file and add this code in the method change

rename_table :{old_table_name}, :{new_table_name}

How to write inside a DIV box with javascript

HTML:

<div id="log"></div>

JS:

document.getElementById("log").innerHTML="WHATEVER YOU WANT...";

In Laravel, the best way to pass different types of flash messages in the session

Simply return with the 'flag' that you want to be treated without using any additional user function. The Controller:

return \Redirect::back()->withSuccess( 'Message you want show in View' );

Notice that I used the 'Success' flag.

The View:

@if( Session::has( 'success' ))
     {{ Session::get( 'success' ) }}
@elseif( Session::has( 'warning' ))
     {{ Session::get( 'warning' ) }} <!-- here to 'withWarning()' -->
@endif

Yes, it really works!

Adding two numbers concatenates them instead of calculating the sum

You need to use javaScript's parseInt() method to turn the strings back into numbers. Right now they are strings so adding two strings concatenates them, which is why you're getting "12".

Switching from zsh to bash on OSX, and back again?

zsh has a builtin command emulate which can emulate different shells by setting the appropriate options, although csh will never be fully emulated.

emulate bash
perform commands
emulate -R zsh

The -R flag restores all the options to their default values for that shell.

See: zsh manual

Insert node at a certain position in a linked list C++

Just have something like this where you traverse till the given position and then insert:

void addNodeAtPos(int data, int pos)
{
  Node* prev = new Node();
  Node* curr = new Node();
  Node* newNode = new Node();
  newNode->data = data;

  int tempPos = 0;   // Traverses through the list

  curr = head;      // Initialize current to head;
  if(head != NULL)
  {
    while(curr->next != NULL && tempPos != pos)
    {
        prev = curr;
        curr = curr->next;
        tempPos++;
    }
    if(pos==0)
    {
       cout << "Adding at Head! " << endl;
       // Call function to addNode from head;
    }
    else if(curr->next == NULL && pos == tempPos+1)
    {
      cout << "Adding at Tail! " << endl;
      // Call function to addNode at tail;
    }
    else if(pos > tempPos+1)
      cout << " Position is out of bounds " << endl;
     //Position not valid

    else
    {
        prev->next = newNode;
        newNode->next = curr;
        cout << "Node added at position: " << pos << endl;
    }
 }
 else
 {
    head = newNode;
    newNode->next=NULL;
    cout << "Added at head as list is empty! " << endl;
 }
}

Best way to check function arguments?

This is not the solution to you, but if you want to restrict the function calls to some specific parameter types then you must use the PROATOR { The Python Function prototype validator }. you can refer the following link. https://github.com/mohit-thakur-721/proator

Concatenate String in String Objective-c

simple one:

[[@"first" stringByAppendingString:@"second"] stringByAppendingString:@"third"];

if you have many STRINGS to Concatenate, you should use NSMutableString for better performance

SVG rounded corner

I'd also consider using a plain old <rect> which provides the rx and ry attributes

MDN SVG docs <- note the second drawn rect element

Android Studio is slow (how to speed up)?

The best way to boost up android studio runtime performance is to use SSD Drive. It will boost the performance as very much. I did all the above things and felt I should go for new laptop, but suddenly I came to know about SSD Drive and I tried it. Its Much Much better.....

Converting NSString to NSDate (and back again)

You can use extensions for this.

extension NSDate {
    //NSString to NSDate
    convenience
    init(dateString:String) {
        let nsDateFormatter = NSDateFormatter()
        nsDateFormatter.dateFormat = "yyyy-MM-dd hh:mm:ss"
        // Add the locale if required here
        let dateObj = nsDateFormatter.dateFromString(dateString)
        self.init(timeInterval:0, sinceDate:dateObj!)
    }

    //NSDate to time string
    func getTime() -> String {
        let timeFormatter = NSDateFormatter()
        timeFormatter.dateFormat = "hh:mm"
        //Can also set the default styles for date or time using .timeStyle or .dateStyle
        return timeFormatter.stringFromDate(self)
    }

    //NSDate to date string
    func getDate() -> String {
        let dateFormatter = NSDateFormatter()
        dateFormatter.dateFormat = "dd, MMM"
        return dateFormatter.stringFromDate(self)
    }

    //NSDate to String
    func getString() -> String {
        let dateFormatter = NSDateFormatter()
        dateFormatter.dateFormat = "yyyy-MM-dd hh:mm:ss"
        return dateFormatter.stringFromDate(self)
    }
}

So while execution actual code will look like follows

    var dateObjFromString = NSDate(dateString: cutDateTime)
    var dateString = dateObjFromString.getDate()
    var timeString = dateObjFromString.getTime()
    var stringFromDate = dateObjFromString.getString()

There are some defaults methods as well but I guess it might not work for the format you have given from documentation

    -dateFromString(_:)
    -stringFromDate(_:)
    -localizedStringFromDate(_ date: NSDate,
                     dateStyle dateStyle: NSDateFormatterStyle,
                     timeStyle timeStyle: NSDateFormatterStyle) -> String

What is the best way to filter a Java Collection?

Consider Google Collections for an updated Collections framework that supports generics.

UPDATE: The google collections library is now deprecated. You should use the latest release of Guava instead. It still has all the same extensions to the collections framework including a mechanism for filtering based on a predicate.

Remove the last line from a file in Bash

OK processing a good amount of data and the output was OK, but had one junk line.

If I piped the output of the script to:

| sed -i '$ d' I would get the following error and finally no output at all sed: no input files

But | head -n -1 worked!

UIAlertController custom font, size, color

Here is an extension for Swift 4.1 and Xcode 9.4.1:

extension UIAlertController{

func addColorInTitleAndMessage(color:UIColor,titleFontSize:CGFloat = 18, messageFontSize:CGFloat = 13){

    let attributesTitle = [NSAttributedStringKey.foregroundColor: color, NSAttributedStringKey.font: UIFont.boldSystemFont(ofSize: titleFontSize)]
    let attributesMessage = [NSAttributedStringKey.foregroundColor: color, NSAttributedStringKey.font: UIFont.systemFont(ofSize: messageFontSize)]
    let attributedTitleText = NSAttributedString(string: self.title ?? "", attributes: attributesTitle)
    let attributedMessageText = NSAttributedString(string: self.message ?? "", attributes: attributesMessage)

    self.setValue(attributedTitleText, forKey: "attributedTitle")
    self.setValue(attributedMessageText, forKey: "attributedMessage")

}}

Can I automatically increment the file build version when using Visual Studio?

Cake supports AssemblyInfo files patching. With cake in hands you have infinite ways to implement automatic version incrementing.

Simple example of incrementing version like C# compiler does:

Setup(() =>
{
    // Executed BEFORE the first task.
    var datetimeNow = DateTime.Now;
    var daysPart = (datetimeNow - new DateTime(2000, 1, 1)).Days;
    var secondsPart = (long)datetimeNow.TimeOfDay.TotalSeconds/2;
    var assemblyInfo = new AssemblyInfoSettings
    {
        Version = "3.0.0.0",
        FileVersion = string.Format("3.0.{0}.{1}", daysPart, secondsPart)
    };
    CreateAssemblyInfo("MyProject/Properties/AssemblyInfo.cs", assemblyInfo);
});

Here:

  • Version - is assembly version. Best practice is to lock major version number and leave remaining with zeroes (like "1.0.0.0").
  • FileVersion - is assembly file version.

Note that you can patch not only versions but also all other necessary information.

Passing an array using an HTML form hidden element

If you want to post an array you must use another notation:

foreach ($postvalue as $value){
<input type="hidden" name="result[]" value="$value.">
}

in this way you have three input fields with the name result[] and when posted $_POST['result'] will be an array

Add context path to Spring Boot application

We can change context root path using a simple entry in the properties file.

application.properties

### Spring boot 1.x #########
server.contextPath=/ClientApp

### Spring boot 2.x #########
server.servlet.context-path=/ClientApp

how to convert integer to string?

If you really want to use String:

NSString *number = [[NSString alloc] initWithFormat:@"%d", 123];

But I would recommend using NSNumber:

NSNumber *number = [[NSNumber alloc] initWithInt:123];

Then just add it to the array.

[array addObject:number];

Don't forget to release it after that, since you created it above.

[number release];

Add URL link in CSS Background Image?

Try wrapping the spans in an anchor tag and apply the background image to that.

HTML:

<div class="header">
    <a href="/">
        <span class="header-title">My gray sea design</span><br />
        <span class="header-title-two">A beautiful design</span>
    </a>
</div>

CSS:

.header {
    border-bottom:1px solid #eaeaea;
}

.header a {
    display: block;
    background-image: url("./images/embouchure.jpg");
    background-repeat: no-repeat;
    height:160px;
    padding-left:280px;
    padding-top:50px;
    width:470px;
    color: #eaeaea;
}

Multiple conditions in an IF statement in Excel VBA

In VBA we can not use if jj = 5 or 6 then we must use if jj = 5 or jj = 6 then

maybe this:

If inputWks.Range("d9") > 0 And (inputWks.Range("d11") = "Restricted_Expenditure" Or inputWks.Range("d11") = "Unrestricted_Expenditure") Then

C Program to find day of week given date

A one-liner is unlikely, but the strptime function can be used to parse your date format and the struct tm argument can be queried for its tm_wday member on systems that modify those fields automatically (e.g. some glibc implementations).

int get_weekday(char * str) {
  struct tm tm;
  memset((void *) &tm, 0, sizeof(tm));
  if (strptime(str, "%d-%m-%Y", &tm) != NULL) {
    time_t t = mktime(&tm);
    if (t >= 0) {
      return localtime(&t)->tm_wday; // Sunday=0, Monday=1, etc.
    }
  }
  return -1;
}

Or you could encode these rules to do some arithmetic in a really long single line:

  • 1 Jan 1900 was a Monday.
  • Thirty days has September, April, June and November; all the rest have thirty-one, saving February alone, which has twenty-eight, rain or shine, and on leap years, twenty-nine.
  • A leap year occurs on any year evenly divisible by 4, but not on a century unless it is divisible by 400.

EDIT: note that this solution only works for dates after the UNIX epoch (1970-01-01T00:00:00Z).

Convert string to variable name in JavaScript

As far as eval vs. global variable solutions...

I think there are advantages to each but this is really a false dichotomy. If you are paranoid of the global namespace just create a temporary namespace & use the same technique.

var tempNamespace = {};
var myString = "myVarProperty";

tempNamespace[myString] = 5;

Pretty sure you could then access as tempNamespace.myVarProperty (now 5), avoiding using window for storage. (The string could also be put directly into the brackets)

Rails 4: assets not loading in production

I may be wrong but those who recommend changing

config.assets.compile = true

The comment on this line reads: #Do not fallback to assets pipeline if a precompiled asset is missed.

This suggests that by setting this to true you are not fixing the problem but rather bypassing it and running the pipeline every time. This must surely kill your performance and defeat the purpose of the pipeline?

I had this same error and it was due to the application running in a sub folder that rails didn't know about.

So my css file where in home/subfolder/app/public/.... but rails was looking in home/app/public/...

try either moving your app out of the subfolder or telling rails that it is in a subfolder.

How do I retrieve an HTML element's actual width and height?

NOTE: this answer was written in 2008. At the time the best cross-browser solution for most people really was to use jQuery. I'm leaving the answer here for posterity and, if you're using jQuery, this is a good way to do it. If you're using some other framework or pure JavaScript the accepted answer is probably the way to go.

As of jQuery 1.2.6 you can use one of the core CSS functions, height and width (or outerHeight and outerWidth, as appropriate).

var height = $("#myDiv").height();
var width = $("#myDiv").width();

var docHeight = $(document).height();
var docWidth = $(document).width();

How to send cookies in a post request with the Python Requests library?

If you want to pass the cookie to the browser, you have to append to the headers to be sent back. If you're using wsgi:

import requests
...


def application(environ, start_response):
    cookie = {'enwiki_session': '17ab96bd8ffbe8ca58a78657a918558'}
    response_headers = [('Content-type', 'text/plain')]
    response_headers.append(('Set-Cookie',cookie))
...

    return [bytes(post_env),response_headers]

I'm successfully able to authenticate with Bugzilla and TWiki hosted on the same domain my python wsgi script is running by passing auth user/password to my python script and pass the cookies to the browser. This allows me to open the Bugzilla and TWiki pages in the same browser and be authenticated. I'm trying to do the same with SuiteCRM but i'm having trouble with SuiteCRM accepting the session cookies obtained from the python script even though it has successfully authenticated.

Command to get nth line of STDOUT

Try this sed version:

ls -l | sed '2 ! d'

It says "delete all the lines that aren't the second one".

Preprocessor check if multiple defines are not defined

FWIW, @SergeyL's answer is great, but here is a slight variant for testing. Note the change in logical or to logical and.

main.c has a main wrapper like this:

#if !defined(TEST_SPI) && !defined(TEST_SERIAL) && !defined(TEST_USB)
int main(int argc, char *argv[]) {
  // the true main() routine.
}

spi.c, serial.c and usb.c have main wrappers for their respective test code like this:

#ifdef TEST_USB
int main(int argc, char *argv[]) {
  // the  main() routine for testing the usb code.
}

config.h Which is included by all the c files has an entry like this:

// Uncomment below to test the serial
//#define TEST_SERIAL


// Uncomment below to test the spi code
//#define TEST_SPI

// Uncomment below to test the usb code
#define TEST_USB

Cannot push to GitHub - keeps saying need merge

use git pull https://github.com/username/repository It's because the Github and remote repositories aren't in sync. If you pull the repo and then Push everything will be in sync and error will go away.

`

How to redirect verbose garbage collection output to a file?

To add to the above answers, there's a good article: Useful JVM Flags – Part 8 (GC Logging) by Patrick Peschlow.

A brief excerpt:

The flag -XX:+PrintGC (or the alias -verbose:gc) activates the “simple” GC logging mode

By default the GC log is written to stdout. With -Xloggc:<file> we may instead specify an output file. Note that this flag implicitly sets -XX:+PrintGC and -XX:+PrintGCTimeStamps as well.

If we use -XX:+PrintGCDetails instead of -XX:+PrintGC, we activate the “detailed” GC logging mode which differs depending on the GC algorithm used.

With -XX:+PrintGCTimeStamps a timestamp reflecting the real time passed in seconds since JVM start is added to every line.

If we specify -XX:+PrintGCDateStamps each line starts with the absolute date and time.

Open and write data to text file using Bash?

#!/bin/sh

FILE="/path/to/file"

/bin/cat <<EOM >$FILE
text1
text2 # This comment will be inside of the file.
The keyword EOM can be any text, but it must start the line and be alone.
 EOM # This will be also inside of the file, see the space in front of EOM.
EOM # No comments and spaces around here, or it will not work.
text4 
EOM

Remove/ truncate leading zeros by javascript/jquery

You should use the "radix" parameter of the "parseInt" function : https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt?redirectlocale=en-US&redirectslug=JavaScript%2FReference%2FGlobal_Objects%2FparseInt

parseInt('015', 10) => 15

if you don't use it, some javascript engine might use it as an octal parseInt('015') => 0

How to play only the audio of a Youtube video using HTML 5?

Embed the video player and use CSS to hide the video. If you do it properly you may even be able to hide only the video and not the controls below it.

However, I'd recommend against it, because it will be a violation of YouTube TOS. Use your own server instead if you really want to play only audio.

Convert list of ints to one number?

Just for completeness, here's a variant that uses print() (works on Python 2.6-3.x):

from __future__ import print_function
try: from cStringIO import StringIO
except ImportError:
     from io import StringIO

def to_int(nums, _s = StringIO()):
    print(*nums, sep='', end='', file=_s)
    s = _s.getvalue()
    _s.truncate(0)
    return int(s)

Time performance of different solutions

I've measured performance of @cdleary's functions. The results are slightly different.

Each function tested with the input list generated by:

def randrange1_10(digit_count): # same as @cdleary
    return [random.randrange(1, 10) for i in xrange(digit_count)]

You may supply your own function via --sequence-creator=yourmodule.yourfunction command-line argument (see below).

The fastest functions for a given number of integers in a list (len(nums) == digit_count) are:

  • len(nums) in 1..30

    def _accumulator(nums):
        tot = 0
        for num in nums:
            tot *= 10
            tot += num
        return tot
    
  • len(nums) in 30..1000

    def _map(nums):
        return int(''.join(map(str, nums)))
    
    def _imap(nums):
        return int(''.join(imap(str, nums)))
    

Figure: N = 1000

|------------------------------+-------------------|
| Fitting polynom              | Function          |
|------------------------------+-------------------|
| 1.00  log2(N)   +  1.25e-015 | N                 |
| 2.00  log2(N)   +  5.31e-018 | N*N               |
| 1.19  log2(N)   +      1.116 | N*log2(N)         |
| 1.37  log2(N)   +      2.232 | N*log2(N)*log2(N) |
|------------------------------+-------------------|
| 1.21  log2(N)   +      0.063 | _interpolation    |
| 1.24  log2(N)   -      0.610 | _genexp           |
| 1.25  log2(N)   -      0.968 | _imap             |
| 1.30  log2(N)   -      1.917 | _map              |

Figure: N = 1000_000

To plot the first figure download cdleary.py and make-figures.py and run (numpy and matplotlib must be installed to plot):

$ python cdleary.py 

Or

$ python make-figures.py --sort-function=cdleary._map \
> --sort-function=cdleary._imap \
> --sort-function=cdleary._interpolation \
> --sort-function=cdleary._genexp --sort-function=cdleary._sum \
> --sort-function=cdleary._reduce --sort-function=cdleary._builtins \
> --sort-function=cdleary._accumulator \
> --sequence-creator=cdleary.randrange1_10 --maxn=1000 

How to import a csv file using python with headers intact, where first column is a non-numerical

For Python 3

Remove the rb argument and use either r or don't pass argument (default read mode).

with open( <path-to-file>, 'r' ) as theFile:
    reader = csv.DictReader(theFile)
    for line in reader:
        # line is { 'workers': 'w0', 'constant': 7.334, 'age': -1.406, ... }
        # e.g. print( line[ 'workers' ] ) yields 'w0'
        print(line)

For Python 2

import csv
with open( <path-to-file>, "rb" ) as theFile:
    reader = csv.DictReader( theFile )
    for line in reader:
        # line is { 'workers': 'w0', 'constant': 7.334, 'age': -1.406, ... }
        # e.g. print( line[ 'workers' ] ) yields 'w0'

Python has a powerful built-in CSV handler. In fact, most things are already built in to the standard library.

What are the differences between .gitignore and .gitkeep?

.gitignore

is a text file comprising a list of files in your directory that git will ignore or not add/update in the repository.

.gitkeep

Since Git removes or doesn't add empty directories to a repository, .gitkeep is sort of a hack (I don't think it's officially named as a part of Git) to keep empty directories in the repository.

Just do a touch /path/to/emptydirectory/.gitkeep to add the file, and Git will now be able to maintain this directory in the repository.

How to send list of file in a folder to a txt file in Linux

you can just use

ls > filenames.txt

(usually, start a shell by using "Terminal", or "shell", or "Bash".) You may need to use cd to go to that folder first, or you can ls ~/docs > filenames.txt

How to capitalize the first character of each word in a string

Using org.apache.commons.lang.StringUtils makes it very simple.

capitalizeStr = StringUtils.capitalize(str);

Javascript - How to show escape characters in a string?

If your goal is to have

str = "Hello\nWorld";

and output what it contains in string literal form, you can use JSON.stringify:

console.log(JSON.stringify(str)); // ""Hello\nWorld""

_x000D_
_x000D_
const str = "Hello\nWorld";_x000D_
const json = JSON.stringify(str);_x000D_
console.log(json); // ""Hello\nWorld""_x000D_
for (let i = 0; i < json.length; ++i) {_x000D_
    console.log(`${i}: ${json.charAt(i)}`);_x000D_
}
_x000D_
.as-console-wrapper {_x000D_
    max-height: 100% !important;_x000D_
}
_x000D_
_x000D_
_x000D_

console.log adds the outer quotes (at least in Chrome's implementation), but the content within them is a string literal (yes, that's somewhat confusing).

JSON.stringify takes what you give it (in this case, a string) and returns a string containing valid JSON for that value. So for the above, it returns an opening quote ("), the word Hello, a backslash (\), the letter n, the word World, and the closing quote ("). The linefeed in the string is escaped in the output as a \ and an n because that's how you encode a linefeed in JSON. Other escape sequences are similarly encoded.

Getting a timestamp for today at midnight?

_x000D_
_x000D_
function getTodaysTimeStamp() {_x000D_
  const currentTimeStamp = Math.round(Date.now() / 1000);_x000D_
  const startOfDay = currentTimeStamp - (currentTimeStamp % 86400);_x000D_
  return { startOfDay, endOfDay: startOfDay + 86400 - 1 };_x000D_
}_x000D_
_x000D_
// starts from sunday_x000D_
function getThisWeeksTimeStamp() {_x000D_
  const currentTimeStamp = Math.round(Date.now() / 1000);_x000D_
  const currentDay = new Date(currentTimeStamp * 1000);_x000D_
  const startOfWeek = currentTimeStamp - (currentDay.getDay() * 86400) - (currentTimeStamp % 86400);_x000D_
  return { startOfWeek, endOfWeek: startOfWeek + 7 * 86400 - 1 };_x000D_
}_x000D_
_x000D_
_x000D_
function getThisMonthsTimeStamp() {_x000D_
  const currentTimeStamp = Math.round(Date.now() / 1000);_x000D_
  const currentDay = new Date(currentTimeStamp * 1000);_x000D_
  const startOfMonth = currentTimeStamp - ((currentDay.getDate() - 1) * 86400) - (currentTimeStamp % 86400);_x000D_
  const currentMonth = currentDay.getMonth() + 1;_x000D_
  let daysInMonth = 0;_x000D_
  if (currentMonth === 2) daysInMonth = 28;_x000D_
  else if ([1, 3, 5, 7, 8, 10, 12].includes(currentMonth)) daysInMonth = 31;_x000D_
  else daysInMonth = 30;_x000D_
  return { startOfMonth, endOfMonth: startOfMonth + daysInMonth * 86400 - 1 };_x000D_
}_x000D_
_x000D_
_x000D_
console.log(getTodaysTimeStamp());_x000D_
console.log(getThisWeeksTimeStamp());_x000D_
console.log(getThisMonthsTimeStamp());
_x000D_
_x000D_
_x000D_

How to log a method's execution time exactly in milliseconds?

You can get really fine timing (seconds.parts of seconds) using this StopWatch class. It uses the high-precision timer in the iPhone. Using NSDate will only get you second(s) accuracy. This version is designed specifically for autorelease and objective-c. I have a c++ version as well if needed. You can find the c++ version here.

StopWatch.h

#import <Foundation/Foundation.h>


@interface StopWatch : NSObject 
{
    uint64_t _start;
    uint64_t _stop;
    uint64_t _elapsed;
}

-(void) Start;
-(void) Stop;
-(void) StopWithContext:(NSString*) context;
-(double) seconds;
-(NSString*) description;
+(StopWatch*) stopWatch;
-(StopWatch*) init;
@end

StopWatch.m

#import "StopWatch.h"
#include <mach/mach_time.h>

@implementation StopWatch

-(void) Start
{
    _stop = 0;
    _elapsed = 0;
    _start = mach_absolute_time();
}
-(void) Stop
{
    _stop = mach_absolute_time();   
    if(_stop > _start)
    {
        _elapsed = _stop - _start;
    }
    else 
    {
        _elapsed = 0;
    }
    _start = mach_absolute_time();
}

-(void) StopWithContext:(NSString*) context
{
    _stop = mach_absolute_time();   
    if(_stop > _start)
    {
        _elapsed = _stop - _start;
    }
    else 
    {
        _elapsed = 0;
    }
    NSLog([NSString stringWithFormat:@"[%@] Stopped at %f",context,[self seconds]]);

    _start = mach_absolute_time();
}


-(double) seconds
{
    if(_elapsed > 0)
    {
        uint64_t elapsedTimeNano = 0;

        mach_timebase_info_data_t timeBaseInfo;
        mach_timebase_info(&timeBaseInfo);
        elapsedTimeNano = _elapsed * timeBaseInfo.numer / timeBaseInfo.denom;
        double elapsedSeconds = elapsedTimeNano * 1.0E-9;
        return elapsedSeconds;
    }
    return 0.0;
}
-(NSString*) description
{
    return [NSString stringWithFormat:@"%f secs.",[self seconds]];
}
+(StopWatch*) stopWatch
{
    StopWatch* obj = [[[StopWatch alloc] init] autorelease];
    return obj;
}
-(StopWatch*) init
{
    [super   init];
    return self;
}

@end

The class has a static stopWatch method that returns an autoreleased object.

Once you call start, use the seconds method to get the elapsed time. Call start again to restart it. Or stop to stop it. You can still read the time (call seconds) anytime after calling stop.

Example In A Function (Timing call of execution)

-(void)SomeFunc
{
   StopWatch* stopWatch = [StopWatch stopWatch];
   [stopWatch Start];

   ... do stuff

   [stopWatch StopWithContext:[NSString stringWithFormat:@"Created %d Records",[records count]]];
}

How can I create a dynamically sized array of structs?

Another option for you is a linked list. You'll need to analyze how your program will use the data structure, if you don't need random access it could be faster than reallocating.

How to get $(this) selected option in jQuery?

Best and shortest way in my opinion for onchange events on the dropdown to get the selected option:

$('option:selected',this);

to get the value attribute:

$('option:selected',this).attr('value');

to get the shown part between the tags:

$('option:selected',this).text();

In your sample:

$("#select-id").change(function(){
  var cur_value = $('option:selected',this).text();
});

Reading/parsing Excel (xls) files with Python

You might also consider running the (non-python) program xls2csv. Feed it an xls file, and you should get back a csv.

css absolute position won't work with margin-left:auto margin-right: auto

I've used this trick to center an absolutely positioned element. Though, you have to know the element's width.

.divtagABS {
    width: 100px;
    position: absolute;
    left: 50%;
    margin-left: -50px;
  }

Basically, you use left: 50%, then back it out half of it's width with a negative margin.

How to install a node.js module without using npm?

Step-by-step:

  • let's say you are working on a project use-gulp which uses(requires) node_modules like gulp and gulp-util.
  • Now you want to make some modifications to gulp-util lib and test it locally with your use-gulp project...
  • Fork gulp-util project on github\bitbucket etc.
  • Switch to your project: cd use-gulp/node_modules
  • Clone gulp-util as gulp-util-dev : git clone https://.../gulp-util.git gulp-util-dev
  • Run npm install to ensure dependencies of gulp-util-dev are available.
  • Now you have a mirror of gulp-util as gulp-util-dev. In your use-gulp project, you can now replace: require('gulp-util')...; call with : require('gulp-util-dev') to test your changes you made to gulp-util-dev

How to make html <select> element look like "disabled", but pass values?

One could use an additional hidden input element with the same name and value as that of the disabled list. This will ensure that the value is passed in $_POST variables.

Eg:

_x000D_
_x000D_
<select name="sel" disabled><option>123</select>_x000D_
<input type="hidden" name="sel" value=123>
_x000D_
_x000D_
_x000D_

java.util.Date to XMLGregorianCalendar

For those that might end up here looking for the opposite conversion (from XMLGregorianCalendar to Date):

XMLGregorianCalendar xcal = <assume this is initialized>;
java.util.Date dt = xcal.toGregorianCalendar().getTime();

Why is the use of alloca() not considered good practice?

Here's why:

char x;
char *y=malloc(1);
char *z=alloca(&x-y);
*z = 1;

Not that anyone would write this code, but the size argument you're passing to alloca almost certainly comes from some sort of input, which could maliciously aim to get your program to alloca something huge like that. After all, if the size isn't based on input or doesn't have the possibility to be large, why didn't you just declare a small, fixed-size local buffer?

Virtually all code using alloca and/or C99 vlas has serious bugs which will lead to crashes (if you're lucky) or privilege compromise (if you're not so lucky).

Javascript string replace with regex to strip off illegal characters

What you need are character classes. In that, you've only to worry about the ], \ and - characters (and ^ if you're placing it straight after the beginning of the character class "[" ).

Syntax: [characters] where characters is a list with characters.

Example:

var cleanString = dirtyString.replace(/[|&;$%@"<>()+,]/g, "");

Set markers for individual points on a line in Matplotlib

You can do:

import matplotlib.pyplot as plt
x = [1,2,3,4,5]
y = [2,1,3,6,7]

plt.plot(x, y, style='.-')
plt.show()

This will return a graph with the data points marked with a dot

Why does the JFrame setSize() method not set the size correctly?

The top border of frame is of size 30.You can write code for printing the coordinate of any point on the frame using MouseInputAdapter.You will find when the cursor is just below the top border of the frame the y coordinate is not zero , its close to 30.Hence if you give size to frame 300 * 300 , the size available for putting the components on the frame is only 300 * 270.So if you need to have size 300 * 300 ,give 300 * 330 size of the frame.

What are allowed characters in cookies?

Years ago MSIE 5 or 5.5 (and probably both) had some serious issue with a "-" in the HTML block if you can believe it. Alhough it's not directly related, ever since we've stored an MD5 hash (containing letters and numbers only) in the cookie to look up everything else in server-side database.

Tried to Load Angular More Than Once

I was having the exact same error. After some hours, I noticed that there was an extra comma in my .JSON file, on the very last key-value pair.

//doesn't work
{
    "key":"value",
    "key":"value",
    "key":"value",
}

Then I just took it off (the last ',') and that solved the problem.

//works
{
    "key":"value",
    "key":"value",
    "key":"value"
}

Removing whitespace from strings in Java

One way to handle String manipulations is StringUtils from Apache commons.

String withoutWhitespace = StringUtils.deleteWhitespace(whitespaces);

You can find it here. commons-lang includes lots more and is well supported.

Best practice to return errors in ASP.NET Web API

It looks like you're having more trouble with Validation than errors/exceptions so I'll say a bit about both.

Validation

Controller actions should generally take Input Models where the validation is declared directly on the model.

public class Customer
{ 
    [Require]
    public string Name { get; set; }
}

Then you can use an ActionFilter that automatically sends validation messages back to the client.

public class ValidationActionFilter : ActionFilterAttribute
{
    public override void OnActionExecuting(HttpActionContext actionContext)
    {
        var modelState = actionContext.ModelState;

        if (!modelState.IsValid) {
            actionContext.Response = actionContext.Request
                 .CreateErrorResponse(HttpStatusCode.BadRequest, modelState);
        }
    }
} 

For more information about this check out http://ben.onfabrik.com/posts/automatic-modelstate-validation-in-aspnet-mvc

Error handling

It's best to return a message back to the client that represents the exception that happened (with relevant status code).

Out of the box you have to use Request.CreateErrorResponse(HttpStatusCode, message) if you want to specify a message. However, this ties the code to the Request object, which you shouldn't need to do.

I usually create my own type of "safe" exception that I expect the client would know how to handle and wrap all others with a generic 500 error.

Using an action filter to handle the exceptions would look like this:

public class ApiExceptionFilterAttribute : ExceptionFilterAttribute
{
    public override void OnException(HttpActionExecutedContext context)
    {
        var exception = context.Exception as ApiException;
        if (exception != null) {
            context.Response = context.Request.CreateErrorResponse(exception.StatusCode, exception.Message);
        }
    }
}

Then you can register it globally.

GlobalConfiguration.Configuration.Filters.Add(new ApiExceptionFilterAttribute());

This is my custom exception type.

using System;
using System.Net;

namespace WebApi
{
    public class ApiException : Exception
    {
        private readonly HttpStatusCode statusCode;

        public ApiException (HttpStatusCode statusCode, string message, Exception ex)
            : base(message, ex)
        {
            this.statusCode = statusCode;
        }

        public ApiException (HttpStatusCode statusCode, string message)
            : base(message)
        {
            this.statusCode = statusCode;
        }

        public ApiException (HttpStatusCode statusCode)
        {
            this.statusCode = statusCode;
        }

        public HttpStatusCode StatusCode
        {
            get { return this.statusCode; }
        }
    }
}

An example exception that my API can throw.

public class NotAuthenticatedException : ApiException
{
    public NotAuthenticatedException()
        : base(HttpStatusCode.Forbidden)
    {
    }
}

Code-first vs Model/Database-first

I think one of the Advantages of code first is that you can back up all the changes you've made to a version control system like Git. Because all your tables and relationships are stored in what are essentially just classes, you can go back in time and see what the structure of your database was before.

What is Dependency Injection?

It means that objects should only have as many dependencies as is needed to do their job and the dependencies should be few. Furthermore, an object’s dependencies should be on interfaces and not on “concrete” objects, when possible. (A concrete object is any object created with the keyword new.) Loose coupling promotes greater reusability, easier maintainability, and allows you to easily provide “mock” objects in place of expensive services.

The “Dependency Injection” (DI) is also known as “Inversion of Control” (IoC), can be used as a technique for encouraging this loose coupling.

There are two primary approaches to implementing DI:

  1. Constructor injection
  2. Setter injection

Constructor injection

It’s the technique of passing objects dependencies to its constructor.

Note that the constructor accepts an interface and not concrete object. Also, note that an exception is thrown if the orderDao parameter is null. This emphasizes the importance of receiving a valid dependency. Constructor Injection is, in my opinion, the preferred mechanism for giving an object its dependencies. It is clear to the developer while invoking the object which dependencies need to be given to the “Person” object for proper execution.

Setter Injection

But consider the following example… Suppose you have a class with ten methods that have no dependencies, but you’re adding a new method that does have a dependency on IDAO. You could change the constructor to use Constructor Injection, but this may force you to changes to all constructor calls all over the place. Alternatively, you could just add a new constructor that takes the dependency, but then how does a developer easily know when to use one constructor over the other. Finally, if the dependency is very expensive to create, why should it be created and passed to the constructor when it may only be used rarely? “Setter Injection” is another DI technique that can be used in situations such as this.

Setter Injection does not force dependencies to be passed to the constructor. Instead, the dependencies are set onto public properties exposed by the object in need. As implied previously, the primary motivators for doing this include:

  1. Supporting dependency injection without having to modify the constructor of a legacy class.
  2. Allowing expensive resources or services to be created as late as possible and only when needed.

Here is the example of how the above code would look like:

public class Person {
    public Person() {}

    public IDAO Address {
        set { addressdao = value; }
        get {
            if (addressdao == null)
              throw new MemberAccessException("addressdao" +
                             " has not been initialized");
            return addressdao;
        }
    }

    public Address GetAddress() {
       // ... code that uses the addressdao object
       // to fetch address details from the datasource ...
    }

    // Should not be called directly;
    // use the public property instead
    private IDAO addressdao;

Print to standard printer from Python?

Unfortunately, there is no standard way to print using Python on all platforms. So you'll need to write your own wrapper function to print.

You need to detect the OS your program is running on, then:

For Linux -

import subprocess
lpr =  subprocess.Popen("/usr/bin/lpr", stdin=subprocess.PIPE)
lpr.stdin.write(your_data_here)

For Windows: http://timgolden.me.uk/python/win32_how_do_i/print.html

More resources:

Print PDF document with python's win32print module?

How do I print to the OS's default printer in Python 3 (cross platform)?

phpinfo() - is there an easy way for seeing it?

From your command line you can run..

php -i

I know it's not the browser window, but you can't see the phpinfo(); contents without making the function call. Obviously, the best approach would be to have a phpinfo script in the root of your web server directory, that way you have access to it at all times via http://localhost/info.php or something similar (NOTE: don't do this in a production environment or somewhere that is publicly accessible)

EDIT: As mentioned by binaryLV, its quite common to have two versions of a php.ini per installation. One for the command line interface (CLI) and the other for the web server interface. If you want to see phpinfo output for your web server make sure you specify the ini file path, for example...

php -c /etc/php/apache2/php.ini -i 

@RequestBody and @ResponseBody annotations in Spring

Below is an example of a method in a Java controller.

@RequestMapping(method = RequestMethod.POST)
@ResponseBody
public HttpStatus something(@RequestBody MyModel myModel) 
{
    return HttpStatus.OK;
}

By using @RequestBody annotation you will get your values mapped with the model you created in your system for handling any specific call. While by using @ResponseBody you can send anything back to the place from where the request was generated. Both things will be mapped easily without writing any custom parser etc.

How does HTTP file upload work?

Let's take a look at what happens when you select a file and submit your form (I've truncated the headers for brevity):

POST /upload?upload_progress_id=12344 HTTP/1.1
Host: localhost:3000
Content-Length: 1325
Origin: http://localhost:3000
... other headers ...
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryePkpFF7tjBAqx29L

------WebKitFormBoundaryePkpFF7tjBAqx29L
Content-Disposition: form-data; name="MAX_FILE_SIZE"

100000
------WebKitFormBoundaryePkpFF7tjBAqx29L
Content-Disposition: form-data; name="uploadedfile"; filename="hello.o"
Content-Type: application/x-object

... contents of file goes here ...
------WebKitFormBoundaryePkpFF7tjBAqx29L--

NOTE: each boundary string must be prefixed with an extra --, just like in the end of the last boundary string. The example above already includes this, but it can be easy to miss. See comment by @Andreas below.

Instead of URL encoding the form parameters, the form parameters (including the file data) are sent as sections in a multipart document in the body of the request.

In the example above, you can see the input MAX_FILE_SIZE with the value set in the form, as well as a section containing the file data. The file name is part of the Content-Disposition header.

The full details are here.

How to get JavaScript variable value in PHP

You might want to start by learning what Javascript and php are. Javascript is a client side script language running in the browser of the machine of the client connected to the webserver on which php runs. These languages can not communicate directly.

Depending on your goal you'll need to issue an AJAX get or post request to the server and return a json/xml/html/whatever response you need and inject the result back in the DOM structure of the site. I suggest Jquery, BackboneJS or any other JS framework for this. See the Jquery documentation for examples.

If you have to pass php data to JS on the same site you can echo the data as JS and turn your php data using json_encode() into JS.

<script type="text/javascript>
    var foo = <?php echo json_encode($somePhpVar); ?>
</script>

Jquery/Ajax Form Submission (enctype="multipart/form-data" ). Why does 'contentType:False' cause undefined index in PHP?

Please set your form action attribute as below it will solve your problem.

<form name="addProductForm" id="addProductForm" action="javascript:;" enctype="multipart/form-data" method="post" accept-charset="utf-8">

jQuery code:

$(document).ready(function () {
    $("#addProductForm").submit(function (event) {

        //disable the default form submission
        event.preventDefault();
        //grab all form data  
        var formData = $(this).serialize();

        $.ajax({
            url: 'addProduct.php',
            type: 'POST',
            data: formData,
            async: false,
            cache: false,
            contentType: false,
            processData: false,
            success: function () {
                alert('Form Submitted!');
            },
            error: function(){
                alert("error in ajax form submission");
            }
        });

        return false;
    });
});

ORA-12514 TNS:listener does not currently know of service requested in connect descriptor

For thoses Who are using spring-boot and jdbc for connection. You have to be careful while writing jdbcUrl in application.properties

With SID in Database connection - source.datasource.jdbcUrl = jdbc:oracle:thin:@[HOST][:PORT]:SID

With Service name in db connection globe.datasource.jdbcUrl = jdbc:oracle:thin:@//[HOST][:PORT]/SERVICE

This worked for me :)

super() raises "TypeError: must be type, not classobj" for new-style class

the correct way to do will be as following in the old-style classes which doesn't inherit from 'object'

class A:
    def foo(self):
        return "Hi there"

class B(A):
    def foo(self, name):
        return A.foo(self) + name

Why Does OAuth v2 Have Both Access and Refresh Tokens?

Why not just make the access_token last as long as the refresh_token and not have a refresh_token?

In addition to great answers other people have provided, there is another reason why we would use refresh tokens and it's to do with claims.

Each token contains claims which can include anything from the user's name, their roles, or the provider which created the claim. As a token is refreshed, these claims are updated.

If we refresh the tokens more often, we are obviously putting more strain on our identity services; however, we are getting more accurate and up-to-date claims.

Close window automatically after printing dialog closes

This worked best for me injecting the HTML into the popup such as <body onload="window.print()"... The above works for IE, Chrome, and FF (on Mac) but no FF on Windows.

https://stackoverflow.com/a/11782214/1322092

var html = '<html><head><title></title>'+
               '<link rel="stylesheet" href="css/mycss.css" type="text/css" />'+
               '</head><body onload="window.focus(); window.print(); window.close()">'+
               data+
               '</body></html>';

Default value for field in Django model

Set editable to False and default to your default value.

http://docs.djangoproject.com/en/stable/ref/models/fields/#editable

b = models.CharField(max_length=7, default='0000000', editable=False)

Also, your id field is unnecessary. Django will add it automatically.

Horizontal scroll on overflow of table

Unless I grossly misunderstood your question, move overflow-x:scroll from .search-table to .search-table-outter.

http://jsfiddle.net/ZXnqM/4/

.search-table-outter {border:2px solid red; overflow-x:scroll;}
.search-table{table-layout: fixed; margin:40px auto 0px auto;   }

As far as I know you can't give scrollbars to tables themselves.

In git, what is the difference between merge --squash and rebase?

Merge commits: retains all of the commits in your branch and interleaves them with commits on the base branchenter image description here

Merge Squash: retains the changes but omits the individual commits from history enter image description here

Rebase: This moves the entire feature branch to begin on the tip of the master branch, effectively incorporating all of the new commits in master

enter image description here

More on here

in querySelector: how to get the first and get the last elements? what traversal order is used in the dom?

Example to get the last input element:

document.querySelector(".groups-container >div:last-child input")

Closing WebSocket correctly (HTML5, Javascript)

Very simple, you close it :)

var myWebSocket = new WebSocket("ws://example.org"); 
myWebSocket.send("Hello Web Sockets!"); 
myWebSocket.close();

Did you check also the following site And check the introduction article of Opera

cmake - find_library - custom library location

Use CMAKE_PREFIX_PATH by adding multiple paths (separated by semicolons and no white spaces). You can set it as an environmental variable to avoid having absolute paths in your cmake configuration files

Notice that cmake will look for config file in any of the following folders where is any of the path in CMAKE_PREFIX_PATH and name is the name of the library you are looking for

<prefix>/                                               (W)
<prefix>/(cmake|CMake)/                                 (W)
<prefix>/<name>*/                                       (W)
<prefix>/<name>*/(cmake|CMake)/                         (W)
<prefix>/(lib/<arch>|lib|share)/cmake/<name>*/          (U)
<prefix>/(lib/<arch>|lib|share)/<name>*/                (U)
<prefix>/(lib/<arch>|lib|share)/<name>*/(cmake|CMake)/  (U)

In your case you need to add to CMAKE_PREFIX_PATH the following two paths:

D:/develop/cmake/libs/libA;D:/develop/cmake/libB

php random x digit number

You can use rand($min, $max) for that exact purpose.

In order to limit the values to values with x digits you can use the following:

$x = 3; // Amount of digits
$min = pow(10,$x);
$max = pow(10,$x+1)-1);
$value = rand($min, $max);

How to set alignment center in TextBox in ASP.NET?

To center align text

input[type='text'] { text-align:center;}

To center align the textbox in the container that it sits in, apply text-align:center to the container.

Drop-down box dependent on the option selected in another drop-down box

for this, I have noticed that it far better to show and hide the tags instead of adding and removing them for the DOM. It performs better that way.

Click a button programmatically - JS

Though this question is rather old, here's a answer :)

What you are asking for can be achieved by using jQuery's .click() event method and .on() event method

So this could be the code:

// Set the global variables
var userImage = $("#img-giLkojRpuK");
var hangoutButton = $("#hangout-giLkojRpuK");

$(document).ready(function() {
    // When the document is ready/loaded, execute function

    // Hide hangoutButton
    hangoutButton.hide();

    // Assign "click"-event-method to userImage
    userImage.on("click", function() {
        console.log("in onclick");
        hangoutButton.click();
    });
});

PRINT statement in T-SQL

So, if you have a statement something like the following, you're saying that you get no 'print' result?

select * from sysobjects
PRINT 'Just selected * from sysobjects'

If you're using SQL Query Analyzer, you'll see that there are two tabs down at the bottom, one of which is "Messages" and that's where the 'print' statements will show up.
If you're concerned about the timing of seeing the print statements, you may want to try using something like

raiserror ('My Print Statement', 10,1) with nowait

This will give you the message immediately as the statement is reached, rather than buffering the output, as the Query Analyzer will do under most conditions.

Oracle query to fetch column names

  1. SELECT * FROM <SCHEMA_NAME.TABLE_NAME> WHERE ROWNUM = 0; --> Note that, this is Query Result, a ResultSet. This is exportable to other formats. And, you can export the Query Result to Text format. Export looks like below when I did SELECT * FROM SATURN.SPRIDEN WHERE ROWNUM = 0; :

    "SPRTELE_PIDM" "SPRTELE_SEQNO" "SPRTELE_TELE_CODE" "SPRTELE_ACTIVITY_DATE" "SPRTELE_PHONE_AREA" "SPRTELE_PHONE_NUMBER" "SPRTELE_PHONE_EXT" "SPRTELE_STATUS_IND" "SPRTELE_ATYP_CODE" "SPRTELE_ADDR_SEQNO" "SPRTELE_PRIMARY_IND" "SPRTELE_UNLIST_IND" "SPRTELE_COMMENT" "SPRTELE_INTL_ACCESS" "SPRTELE_DATA_ORIGIN" "SPRTELE_USER_ID" "SPRTELE_CTRY_CODE_PHONE" "SPRTELE_SURROGATE_ID" "SPRTELE_VERSION" "SPRTELE_VPDI_CODE"

  2. DESCRIBE <TABLE_NAME> --> Note: This is script output.

CMD: Export all the screen content to a text file

From command prompt Run as Administrator. Example below is to print a list of Services running on your PC run the command below:

net start > c:\netstart.txt

You should see a copy of the text file you just exported with a listing all the PC services running at the root of your C:\ drive.

What is the mouse down selector in CSS?

I think you mean the active state

 button:active{
  //some styling
 }

These are all the possible pseudo states a link can have in CSS:

a:link {color:#FF0000;}    /* unvisited link, same as regular 'a' */
a:hover {color:#FF00FF;}   /* mouse over link */
a:focus {color:#0000FF;}   /* link has focus */
a:active {color:#0000FF;}  /* selected link */
a:visited {color:#00FF00;} /* visited link */

See also: http://www.w3.org/TR/selectors/#the-user-action-pseudo-classes-hover-act

How to remove decimal values from a value of type 'double' in Java

Try:

String newValue = String.format("%d", (int)d);

jQuery .on('change', function() {} not triggering for dynamically created inputs

you can use:

$('body').ready(function(){
   $(document).on('change', '#elemID', function(){
      // do something
   });
});

It works with me.

Disable back button in android

If you want to make sure your android client application is logged out from some server before your Activity gets killed --> log out with a service on its own thread (that's what you're supposed to do anyway).

Disabling the back button won't solve anything for you. You'll still have the same problem when the user receives a phone call for instance. When a phone call is received, your activity has about as much chances of getting killed before it gets a reliable answer back from the network.

That's why you should let a service wait on its own thread for the answer from the network, and then make it try again if it doesn't succeed. The android service is not only much less likely to get killed before it gets an answer back, but should it really get killed before finishing the job, it can always get revived by AlarmManager to try again.

Are PHP Variables passed by value or by reference?

PHP variables are assigned by value, passed to functions by value and when containing/representing objects are passed by reference. You can force variables to pass by reference using an '&'.

Assigned by value/reference example:

$var1 = "test";
$var2 = $var1;
$var2 = "new test";
$var3 = &$var2;
$var3 = "final test";

print ("var1: $var1, var2: $var2, var3: $var3);

output:

var1: test, var2: final test, var3: final test

Passed by value/reference example:

$var1 = "foo";
$var2 = "bar";

changeThem($var1, $var2);

print "var1: $var1, var2: $var2";

function changeThem($var1, &$var2){
    $var1 = "FOO";
    $var2 = "BAR";
}

output:

var1: foo, var2 BAR

Object variables passed by reference example:

class Foo{
    public $var1;

    function __construct(){
        $this->var1 = "foo";
    }

    public function printFoo(){
        print $this->var1;
    }
}


$foo = new Foo();

changeFoo($foo);

$foo->printFoo();

function changeFoo($foo){
    $foo->var1 = "FOO";
}

output:

FOO

(The last example could be better probably.)

Makefiles with source files in different directories

I suggest to use autotools:

//## Place generated object files (.o) into the same directory as their source files, in order to avoid collisions when non-recursive make is used.

AUTOMAKE_OPTIONS = subdir-objects

just including it in Makefile.am with the other quite simple stuff.

Here is the tutorial.

Android marshmallow request permission?

I went through all answers, but doesn't satisfied my exact needed answer, so here is an example that I wrote and perfectly works, even user clicks the Don't ask again checkbox.

  1. Create a method that will be called when you want to ask for runtime permission like readContacts() or you can also have openCamera() as shown below:

    private void readContacts() {
        if (!askContactsPermission()) {
            return;
        } else {
            queryContacts();
        } }
    

Now we need to make askContactsPermission(), you can also name it as askCameraPermission() or whatever permission you are going to ask.

    private boolean askContactsPermission() {
    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
        return true;
    }
    if (checkSelfPermission(READ_CONTACTS) == PackageManager.PERMISSION_GRANTED) {
        return true;
    }
    if (shouldShowRequestPermissionRationale(READ_CONTACTS)) {
        Snackbar.make(parentLayout, R.string.permission_rationale, Snackbar.LENGTH_INDEFINITE)
                .setAction(android.R.string.ok, new View.OnClickListener() {
                    @Override
                    @TargetApi(Build.VERSION_CODES.M)
                    public void onClick(View v) {
                        requestPermissions(new String[]{READ_CONTACTS}, REQUEST_READ_CONTACTS);
                    }
                }).show();
    } else if (contactPermissionNotGiven) {
        openPermissionSettingDialog();
    } else {
        requestPermissions(new String[]{READ_CONTACTS}, REQUEST_READ_CONTACTS);
        contactPermissionNotGiven = true;

    }
    return false;
}

Before writing this function make sure you have defined the below instance variable as shown:

    private View parentLayout;
    private boolean contactPermissionNotGiven;;


/**
 * Id to identity READ_CONTACTS permission request.
 */
private static final int REQUEST_READ_CONTACTS = 0;

Now final step to override the onRequestPermissionsResult method as shown below:

/**
 * Callback received when a permissions request has been completed.
 */
@RequiresApi(api = Build.VERSION_CODES.M)
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
                                       @NonNull int[] grantResults) {
    if (requestCode == REQUEST_READ_CONTACTS) {
        if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            queryContacts();
        }
    }
}

Here we are done with the RunTime permissions, the addon is the openPermissionSettingDialog() which simply open the Setting screen if user have permanently disable the permission by clicking Don't ask again checkbox. below is the method:

    private void openPermissionSettingDialog() {
    String message = getString(R.string.message_permission_disabled);
    AlertDialog alertDialog =
            new AlertDialog.Builder(MainActivity.this, AlertDialog.THEME_DEVICE_DEFAULT_LIGHT)
                    .setMessage(message)
                    .setPositiveButton(getString(android.R.string.ok),
                            new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    Intent intent = new Intent();
                                    intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
                                    Uri uri = Uri.fromParts("package", getPackageName(), null);
                                    intent.setData(uri);
                                    startActivity(intent);
                                    dialog.cancel();
                                }
                            }).show();
    alertDialog.setCanceledOnTouchOutside(true);
}

What we missed ? 1. Defining the used strings in strings.xml

_x000D_
_x000D_
<string name="permission_rationale">"Contacts permissions are needed to display Contacts."</string>_x000D_
    <string name="message_permission_disabled">You have disabled the permissions permanently,_x000D_
        To enable the permissions please go to Settings -> Permissions and enable the required Permissions,_x000D_
        pressing OK you will be navigated to Settings screen</string>
_x000D_
_x000D_
_x000D_

  1. Initializing the parentLayout variable inside onCreate method

    parentLayout = findViewById(R.id.content);

  2. Defining the required permission in AndroidManifest.xml

_x000D_
_x000D_
<uses-permission android:name="android.permission.READ_CONTACTS" />
_x000D_
_x000D_
_x000D_

  1. The queryContacts method, based on your need or the runtime permission you can call your method before which the permission was needed. in my case I simply use the loader to fetch the contact as shown below:

    private void queryContacts() {
    getLoaderManager().initLoader(0, null, this);}
    

This works great happy coding :)

How to decode JWT Token?

new JwtSecurityTokenHandler().ReadToken("") will return a SecurityToken

new JwtSecurityTokenHandler().ReadJwtToken("") will return a JwtSecurityToken

If you just change the method you are using you can avoid the cast in the above answer

What key shortcuts are to comment and uncomment code?

From your screenshot it appears you have ReSharper installed.

Depending on the key binding options you chose when you installed it, some of your standard shortcuts may now be redirected to ReSharper commands. It's worth checking, for example Ctrl+E, C is used by R# for the code cleanup dialog.

Can I scale a div's height proportionally to its width using CSS?

If you want vertical sizing proportional to a width set in pixels on an enclosing div, I believe you need an extra element, like so:

#html

<div class="ptest">
    <div class="ptest-wrap">
        <div class="ptest-inner">
            Put content here
        </div>
    </div>
</div>

#css
.ptest {
  width: 200px;
  position: relative;
}

.ptest-wrap {
    padding-top: 60%;
}
.ptest-inner {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: #333;
}

Here's the 2 div solution that doesn't work. Note the 60% vertical padding is proportional to the window width, not the div.ptest width:

http://jsfiddle.net/d85FM/

Here's the example with the code above, which does work:

http://jsfiddle.net/mmq29/

Getters \ setters for dummies

In addition to @millimoose's answer, setters can also be used to update other values.

function Name(first, last) {
    this.first = first;
    this.last = last;
}

Name.prototype = {
    get fullName() {
        return this.first + " " + this.last;
    },

    set fullName(name) {
        var names = name.split(" ");
        this.first = names[0];
        this.last = names[1];
    }
};

Now, you can set fullName, and first and last will be updated and vice versa.

n = new Name('Claude', 'Monet')
n.first # "Claude"
n.last # "Monet"
n.fullName # "Claude Monet"
n.fullName = "Gustav Klimt"
n.first # "Gustav"
n.last # "Klimt"

Styling HTML email for Gmail

I had the same problem while designing a template in Mailjet. Solution of the problem was minified CSS code inside <style> tags.

Writing numerical values on the plot with Matplotlib

You can use the annotate command to place text annotations at any x and y values you want. To place them exactly at the data points you could do this

import numpy
from matplotlib import pyplot

x = numpy.arange(10)
y = numpy.array([5,3,4,2,7,5,4,6,3,2])

fig = pyplot.figure()
ax = fig.add_subplot(111)
ax.set_ylim(0,10)
pyplot.plot(x,y)
for i,j in zip(x,y):
    ax.annotate(str(j),xy=(i,j))

pyplot.show()

If you want the annotations offset a little, you could change the annotate line to something like

ax.annotate(str(j),xy=(i,j+0.5))

How do I create and access the global variables in Groovy?

Like all OO languages, Groovy has no concept of "global" by itself (unlike, say, BASIC, Python or Perl).

If you have several methods that need to share the same variable, use a field:

class Foo {
    def a;

    def foo() {
        a = 1;
    }
    def bar() {
        print a;
    }
}

Go to beginning of line without opening new line in VI

You can also use

:-0

This sets the cursor at the present line (blank here) at the 0 column.

Browserslist: caniuse-lite is outdated. Please run next command `npm update caniuse-lite browserslist`

As mentioned in Scott Kuhl's answer this issue is mentioned in https://github.com/madskristensen/WebCompiler/issues/413

For me, running the command npm i caniuse-lite- browserslist only worked for about 1/2 a day before it was an issue again.

The following solution, mentioned in the post, works much better. This updates the node.js file so that it uses console.log instead of console.warn when returning these errors.

You can manually update this file located at C:\Users\[Username]\AppData\Local\Temp\WebCompiler[VersionNumber]\node_modules\browserslist

Or, so that it is done automatically, add the following to your .csproj file by:

  1. Right click on project file and select "Unload Project"
  2. Edit the .csproj file
  3. Paste the following into the project file. I pasted it towards the end of the file, before the </Project> end tag and before the build web compiler package was imported.
    <ItemGroup>
        <PackageReference Include="MSBuildTasks" Version="1.5.0.235">
            <PrivateAssets>all</PrivateAssets>
            <IncludeAssets>runtime; build; native; contentfiles; analyzers</IncludeAssets>
        </PackageReference>
    </ItemGroup>
    <PropertyGroup>
        <TempFolder>$([System.IO.Path]::GetTempPath())</TempFolder>
    </PropertyGroup>
    <ItemGroup>
        <BrowsersListNodeJsFiles Include="$(TempFolder)\WebCompiler*\node_modules\browserslist\node.js" />
    </ItemGroup>
    <Target Name="BrowsersListWarningsAsInfo" BeforeTargets="WebCompile">
        <FileUpdate Files="@(BrowsersListNodeJsFiles)"
                    Regex="console.warn"
                    ReplacementText="console.log" />
    </Target>

  1. Reload the project back into the solution.

Android sqlite how to check if a record exists

One thing the top voted answer did not mention was that you need single quotes, 'like this', around your search value if it is a text value like so:

public boolean checkIfMyTitleExists(String title) {
    String Query = "Select * from " + TABLE_NAME + " where " + COL1 + " = " + "'" + title + "'";
    Cursor cursor = database.rawQuery(Query, null);
    if(cursor.getCount() <= 0){
        cursor.close();
        return false;
    }
    cursor.close();

    return true;
}

Otherwise, you will get a "SQL(query) error or missing database" error like I did without the single quotes around the title field.

If it is a numeric value, it does not need single quotes.

Refer to this SQL post for more details

Are there any style options for the HTML5 Date picker?

You can use the following CSS to style the input element.

_x000D_
_x000D_
input[type="date"] {_x000D_
  background-color: red;_x000D_
  outline: none;_x000D_
}_x000D_
_x000D_
input[type="date"]::-webkit-clear-button {_x000D_
  font-size: 18px;_x000D_
  height: 30px;_x000D_
  position: relative;_x000D_
}_x000D_
_x000D_
input[type="date"]::-webkit-inner-spin-button {_x000D_
  height: 28px;_x000D_
}_x000D_
_x000D_
input[type="date"]::-webkit-calendar-picker-indicator {_x000D_
  font-size: 15px;_x000D_
}
_x000D_
<input type="date" value="From" name="from" placeholder="From" required="" />
_x000D_
_x000D_
_x000D_

using OR and NOT in solr query

Solr currently checks for a "pure negative" query and inserts *:* (which matches all documents) so that it works correctly.

-foo is transformed by solr into (*:* -foo)

The big caveat is that Solr only checks to see if the top level query is a pure negative query! So this means that a query like bar OR (-foo) is not changed since the pure negative query is in a sub-clause of the top level query. You need to transform this query yourself into bar OR (*:* -foo)

You may check the solr query explanation to verify the query transformation:

?q=-title:foo&debug=query

is transformed to

(+(-title:foo +MatchAllDocsQuery(*:*))

Differences between contentType and dataType in jQuery ajax function

enter image description here

In English:

  • ContentType: When sending data to the server, use this content type. Default is application/x-www-form-urlencoded; charset=UTF-8, which is fine for most cases.
  • Accepts: The content type sent in the request header that tells the server what kind of response it will accept in return. Depends on DataType.
  • DataType: The type of data that you're expecting back from the server. If none is specified, jQuery will try to infer it based on the MIME type of the response. Can be text, xml, html, script, json, jsonp.

Can I target all <H> tags with a single selector?

You can also use PostCSS and the custom selectors plugin

@custom-selector :--headings h1, h2, h3, h4, h5, h6;

article :--headings {
  margin-top: 0;
}

Output:

article h1,
article h2,
article h3,
article h4,
article h5,
article h6 {
  margin-top: 0;
}

Regular expression to match a dot

A . in regex is a metacharacter, it is used to match any character. To match a literal dot, you need to escape it, so \.

How to Run Terminal as Administrator on Mac Pro

search for terminal after opening the termincal type

su <admin-user-name>   //su - switch user

enter and then give the admin password then run your sudo commands e.g:

sudo open MySQLWorkbench.app

How can I switch to another branch in git?

With Git 2.23 onwards, one can use git switch <branch name> to switch branches.

How to define hash tables in Bash?

Bash 3 solution:

In reading some of the answers I put together a quick little function I would like to contribute back that might help others.

# Define a hash like this
MYHASH=("firstName:Milan"
        "lastName:Adamovsky")

# Function to get value by key
getHashKey()
 {
  declare -a hash=("${!1}")
  local key
  local lookup=$2

  for key in "${hash[@]}" ; do
   KEY=${key%%:*}
   VALUE=${key#*:}
   if [[ $KEY == $lookup ]]
   then
    echo $VALUE
   fi
  done
 }

# Function to get a list of all keys
getHashKeys()
 {
  declare -a hash=("${!1}")
  local KEY
  local VALUE
  local key
  local lookup=$2

  for key in "${hash[@]}" ; do
   KEY=${key%%:*}
   VALUE=${key#*:}
   keys+="${KEY} "
  done

  echo $keys
 }

# Here we want to get the value of 'lastName'
echo $(getHashKey MYHASH[@] "lastName")


# Here we want to get all keys
echo $(getHashKeys MYHASH[@])

How to use color picker (eye dropper)?

Currently, the eyedropper tool is not working in my version of Chrome (as described above), though it worked for me in the past. I hear it is being updated in the latest version of Chrome.

However, I'm able to grab colors easily in Firefox.

  1. Open page in Firefox
  2. Hamburger Menu -> Web Developer -> Eyedropper
  3. Drag eyedropper tool over the image... Click.
    Color is copied to your clipboard, and eyedropper tool goes away.
  4. Paste color code

In case you cannot get the eyedropper tool to work in Chrome, this is a good work around.
I also find it easier to access :-)

How can I get a vertical scrollbar in my ListBox?

Scroll Bar is added to the List box automatically unless its visibility is set to Hidden. Whenever the size of List Items exceeds the one, which can be shown inside a list box vertical or horizontal list box can be seen during the run time.

Getting the closest string match

You might be interested in this blog post.

http://seatgeek.com/blog/dev/fuzzywuzzy-fuzzy-string-matching-in-python

Fuzzywuzzy is a Python library that provides easy distance measures such as Levenshtein distance for string matching. It is built on top of difflib in the standard library and will make use of the C implementation Python-levenshtein if available.

http://pypi.python.org/pypi/python-Levenshtein/

How to parse/format dates with LocalDateTime? (Java 8)

Parsing a string with date and time into a particular point in time (Java calls it an "Instant") is quite complicated. Java has been tackling this in several iterations. The latest one, java.time and java.time.chrono, covers almost all needs (except Time Dilation :) ).

However, that complexity brings a lot of confusion.

The key to understand date parsing is:

Why does Java have so many ways to parse a date

  1. There are several systems to measure a time. For instance, the historical Japanese calendars were derived from the time ranges of the reign of the respective emperor or dynasty. Then there is e.g. UNIX timestamp. Fortunately, the whole (business) world managed to use the same.
  2. Historically, the systems were being switched from/to, for various reasons. E.g. from Julian calendar to Gregorian calendar in 1582. So 'western' dates before that need to be treated differently.
  3. And of course the change did not happen at once. Because the calendar came from the headquarteds of some religion and other parts of Europe believed in other dieties, for instance Germany did not switch until the year 1700.

...and why is the LocalDateTime, ZonedDateTime et al. so complicated

  1. There are time zones. A time zone is basically a "stripe"*[1] of the Earth's surface whose authorities follow the same rules of when does it have which time offset. This includes summer time rules.
    The time zones change over time for various areas, mostly based on who conquers whom. And one time zone's rules change over time as well.

  2. There are time offsets. That is not the same as time zones, because a time zone may be e.g. "Prague", but that has summer time offset and winter time offset.
    If you get a timestamp with a time zone, the offset may vary, depending on what part of the year it is in. During the leap hour, the timestamp may mean 2 different times, so without additional information, it can't be reliably converted.
    Note: By timestamp I mean "a string that contains a date and/or time, optionally with a time zone and/or time offset."

  3. Several time zones may share the same time offset for certain periods. For instance, GMT/UTC time zone is the same as "London" time zone when the summer time offset is not in effect.

To make it a bit more complicated (but that's not too important for your use case) :

  1. The scientists observe Earth's dynamic, which changes over time; based on that, they add seconds at the end of individual years. (So 2040-12-31 24:00:00 may be a valid date-time.) This needs regular updates of the metadata that systems use to have the date conversions right. E.g. on Linux, you get regular updates to the Java packages including these new data.
  2. The updates do not always keep the previous behavior for both historical and future timestamps. So it may happen that parsing of the two timestamps around some time zone's change comparing them may give different results when running on different versions of the software. That also applies to comparing between the affected time zone and other time zone.

    Should this cause a bug in your software, consider using some timestamp that does not have such complicated rules, like UNIX timestamp.

  3. Because of 7, for the future dates, we can't convert dates exactly with certainty. So, for instance, current parsing of 8524-02-17 12:00:00 may be off a couple of seconds from the future parsing.

JDK's APIs for this evolved with the contemporary needs

  • The early Java releases had just java.util.Date which had a bit naive approach, assuming that there's just the year, month, day, and time. This quickly did not suffice.
  • Also, the needs of the databases were different, so quite early, java.sql.Date was introduced, with it's own limitations.
  • Because neither covered different calendars and time zones well, the Calendar API was introduced.
  • This still did not cover the complexity of the time zones. And yet, the mix of the above APIs was really a pain to work with. So as Java developers started working on global web applications, libraries that targeted most use cases, like JodaTime, got quickly popular. JodaTime was the de-facto standard for about a decade.
  • But the JDK did not integrate with JodaTime, so working with it was a bit cumbersome. So, after a very long discussion on how to approach the matter, JSR-310 was created mainly based on JodaTime.

How to deal with it in Java's java.time

Determine what type to parse a timestamp to

When you are consuming a timestamp string, you need to know what information it contains. This is the crucial point. If you don't get this right, you end up with a cryptic exceptions like "Can't create Instant" or "Zone offset missing" or "unknown zone id" etc.

Does it contain the date and the time?

  1. Does it have a time offset?
    A time offset is the +hh:mm part. Sometimes, +00:00 may be substituted with Z as 'Zulu time', UTC as Universal Time Coordinated, or GMT as Greenwich Mean Time. These also set the time zone.
    For these timestamps, you use OffsetDateTime.

  2. Does it have a time zone?
    For these timestamps, you use ZonedDateTime.
    Zone is specified either by

    • name ("Prague", "Pacific Standard Time", "PST"), or
    • "zone ID" ("America/Los_Angeles", "Europe/London"), represented by java.time.ZoneId.

    The list of time zones is compiled by a "TZ database", backed by ICAAN.

    According to ZoneId's javadoc, The zone id's can also somehow be specified as Z and offset. I'm not sure how this maps to real zones. If the timestamp, which only has a TZ, falls into a leap hour of time offset change, then it is ambiguous, and the interpretation is subject of ResolverStyle, see below.

  3. If it has neither, then the missing context is assumed or neglected. And the consumer has to decide. So it needs to be parsed as LocalDateTime and converted to OffsetDateTime by adding the missing info:

    • You can assume that it is a UTC time. Add the UTC offset of 0 hours.
    • You can assume that it is a time of the place where the conversion is happening. Convert it by adding the system's time zone.
    • You can neglect and just use it as is. That is useful e.g. to compare or substract two times (see Duration), or when you don't know and it doesn't really matter (e.g. local bus schedule).

Partial time information

  • Based on what the timestamp contains, you can take LocalDate, LocalTime, OffsetTime, MonthDay, Year, or YearMonth out of it.

If you have the full information, you can get a java.time.Instant. This is also internally used to convert between OffsetDateTime and ZonedDateTime.

Figure out how to parse it

There is an extensive documentation on DateTimeFormatter which can both parse a timestamp string and format to string.

The pre-created DateTimeFormatters should cover moreless all standard timestamp formats. For instance, ISO_INSTANT can parse 2011-12-03T10:15:30.123457Z.

If you have some special format, then you can create your own DateTimeFormatter (which is also a parser).

private static final DateTimeFormatter TIMESTAMP_PARSER = new DateTimeFormatterBuilder()
   .parseCaseInsensitive()
   .append(DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SX"))
   .toFormatter();

I recommend to look at the source code of DateTimeFormatter and get inspired on how to build one using DateTimeFormatterBuilder. While you're there, also have a look at ResolverStyle which controls whether the parser is LENIENT, SMART or STRICT for the formats and ambiguous information.

TemporalAccessor

Now, the frequent mistake is to go into the complexity of TemporalAccessor. This comes from how the developers were used to work with SimpleDateFormatter.parse(String). Right, DateTimeFormatter.parse("...") gives you TemporalAccessor.

// No need for this!
TemporalAccessor ta = TIMESTAMP_PARSER.parse("2011-... etc");

But, equiped with the knowledge from the previous section, you can conveniently parse into the type you need:

OffsetDateTime myTimestamp = OffsetDateTime.parse("2011-12-03T10:15:30.123457Z", TIMESTAMP_PARSER);

You do not actually need to the DateTimeFormatter either. The types you want to parse have the parse(String) methods.

OffsetDateTime myTimestamp = OffsetDateTime.parse("2011-12-03T10:15:30.123457Z");

Regarding TemporalAccessor, you can use it if you have a vague idea of what information there is in the string, and want to decide at runtime.

I hope I shed some light of understanding onto your soul :)

Note: There's a backport of java.time to Java 6 and 7: ThreeTen-Backport. For Android it has ThreeTenABP.

[1] Not just that they are not stripes, but there also some weird extremes. For instance, some neighboring pacific islands have +14:00 and -11:00 time zones. That means, that while on one island, there is 1st May 3 PM, on another island not so far, it is still 30 April 12 PM (if I counted correctly :) )

'Access-Control-Allow-Origin' issue when API call made from React (Isomorphic app)

I faced the same error today, using React with Typescript and a back-end using Java Spring boot, if you have a hand on your back-end you can simply add a configuration file for the CORS.

For the below example I set allowed origin to * to allow all but you can be more specific and only set url like http://localhost:3000.

import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.cors.CorsConfiguration;
import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
import org.springframework.web.filter.CorsFilter;

@Configuration
public class AppCorsConfiguration {
    @Bean
    public FilterRegistrationBean corsFilter() {
        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
        CorsConfiguration config = new CorsConfiguration();
        config.setAllowCredentials(true);
        config.addAllowedOrigin("*");
        config.addAllowedHeader("*");
        config.addAllowedMethod("*");
        source.registerCorsConfiguration("/**", config);
        FilterRegistrationBean bean = new FilterRegistrationBean(new CorsFilter(source));
        bean.setOrder(0);
        return bean;
    }
}

jQuery UI - Close Dialog When Clicked Outside

I ended up using this code which should work on any open dialogs on the page, ignores clicks on tooltips, and cleans up the resources of the dialog being closed as well.


        $(document).mousedown(function(e) {
            var clicked = $(e.target); // get the element clicked
            if (clicked.is('.ui-dialog-content, .ui-dialog-titlebar, .ui-tooltip') || clicked.parents().is('.ui-dialog-content, .ui-dialog-titlebar, .ui-tooltip')) {
                return; // click happened within the dialog, do nothing here
            } else { // click was outside the dialog, so close it
                $('.ui-dialog-content').dialog("close");
                $('.ui-dialog-content').dialog("destroy");
                $('.ui-dialog-content').detach();

            }
        });

What does += mean in Python?

a += b

is in this case the same as

a = a + b

In this case cnt += 1 means that cnt is increased by one.

Note that the code you pasted will loop indefinitely if cnt > 0 and len(aStr) > 1.

Edit: quote Carl Meyer: ``[..] the answer is misleadingly mostly correct. There is a subtle but very significant difference between + and +=, see Bastien's answer.''.

Creating a search form in PHP to search a database?

You're getting errors 'table liam does not exist' because the table's name is Liam which is not the same as liam. MySQL table names are case sensitive.

How can I delete a query string parameter in JavaScript?

Copied from bobince answer, but made it support question marks in the query string, eg

http://www.google.com/search?q=test???+something&aq=f

Is it valid to have more than one question mark in a URL?

function removeUrlParameter(url, parameter) {
  var urlParts = url.split('?');

  if (urlParts.length >= 2) {
    // Get first part, and remove from array
    var urlBase = urlParts.shift();

    // Join it back up
    var queryString = urlParts.join('?');

    var prefix = encodeURIComponent(parameter) + '=';
    var parts = queryString.split(/[&;]/g);

    // Reverse iteration as may be destructive
    for (var i = parts.length; i-- > 0; ) {
      // Idiom for string.startsWith
      if (parts[i].lastIndexOf(prefix, 0) !== -1) {
        parts.splice(i, 1);
      }
    }

    url = urlBase + '?' + parts.join('&');
  }

  return url;
}

Convert NSNumber to int in Objective-C

Have a look at the documentation. Use the intValue method:

NSNumber *number = [dict objectForKey:@"integer"];
int intValue = [number intValue];

Excel Looping through rows and copy cell values to another worksheet

Private Sub CommandButton1_Click() 

Dim Z As Long 
Dim Cellidx As Range 
Dim NextRow As Long 
Dim Rng As Range 
Dim SrcWks As Worksheet 
Dim DataWks As Worksheet 
Z = 1 
Set SrcWks = Worksheets("Sheet1") 
Set DataWks = Worksheets("Sheet2") 
Set Rng = EntryWks.Range("B6:ad6") 

NextRow = DataWks.UsedRange.Rows.Count 
NextRow = IIf(NextRow = 1, 1, NextRow + 1) 

For Each RA In Rng.Areas 
    For Each Cellidx In RA 
        Z = Z + 1 
        DataWks.Cells(NextRow, Z) = Cellidx 
    Next Cellidx 
Next RA 
End Sub

Alternatively

Worksheets("Sheet2").Range("P2").Value = Worksheets("Sheet1").Range("L10") 

This is a CopynPaste - Method

Sub CopyDataToPlan()

Dim LDate As String
Dim LColumn As Integer
Dim LFound As Boolean

On Error GoTo Err_Execute

'Retrieve date value to search for
LDate = Sheets("Rolling Plan").Range("B4").Value

Sheets("Plan").Select

'Start at column B
LColumn = 2
LFound = False

While LFound = False

  'Encountered blank cell in row 2, terminate search
  If Len(Cells(2, LColumn)) = 0 Then
     MsgBox "No matching date was found."
     Exit Sub

  'Found match in row 2
  ElseIf Cells(2, LColumn) = LDate Then

     'Select values to copy from "Rolling Plan" sheet
     Sheets("Rolling Plan").Select
     Range("B5:H6").Select
     Selection.Copy

     'Paste onto "Plan" sheet
     Sheets("Plan").Select
     Cells(3, LColumn).Select
     Selection.PasteSpecial Paste:=xlValues, Operation:=xlNone, SkipBlanks:= _
     False, Transpose:=False

     LFound = True
     MsgBox "The data has been successfully copied."

     'Continue searching
      Else
         LColumn = LColumn + 1
      End If

   Wend

   Exit Sub

Err_Execute:
  MsgBox "An error occurred."

End Sub

And there might be some methods doing that in Excel.

Stop setInterval call in JavaScript

If you set the return value of setInterval to a variable, you can use clearInterval to stop it.

var myTimer = setInterval(...);
clearInterval(myTimer);

How do I get the SelectedItem or SelectedIndex of ListView in vb.net?

If you want to select the same item in a listbox using a listview, you can use:

Private Sub ListView1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ListView1.SelectedIndexChanged
    For aa As Integer = 0 To ListView1.SelectedItems.Count - 1
        ListBox1.SelectedIndex = ListView1.SelectedIndices(aa)
    Next
End Sub

Model Binding to a List MVC 4

A clean solution could be create a generic class to handle the list, so you don't need to create a different class each time you need it.

public class ListModel<T>
{
    public List<T> Items { get; set; }

    public ListModel(List<T> list) {
        Items = list;
    }
}

and when you return the View you just need to simply do:

List<customClass> ListOfCustomClass = new List<customClass>();
//Do as needed...
return View(new ListModel<customClass>(ListOfCustomClass));

then define the list in the model:

@model ListModel<customClass>

and ready to go:

@foreach(var element in Model.Items) {
  //do as needed...
}

Laravel: Error [PDOException]: Could not Find Driver in PostgreSQL

I had the same issue. This is what worked for me.

There are 2 php.ini files:

  • C:\wamp\bin\apache\apache2.4.9\bin
  • C:\wamp\bin\php\php5.5.12

NOTE: This is using my version of PHP and Apache, change to what yours are.

The php.ini file located in the both folders is what you need to update, the extentions:

  • extension=php_pdo_pgsql.dll
  • extension=php_pgsql.dll

These are what you need to uncomment (remove the ; symbol).

Restart both Wamp and the Command Prompt.

Hopefully it will work for you :).

Angular - POST uploaded file

Looking onto this issue Github - Request/Upload progress handling via @angular/http, angular2 http does not support file upload yet.

For very basic file upload I created such service function as a workaround (using ???????'s answer):

  uploadFile(file:File):Promise<MyEntity> {
    return new Promise((resolve, reject) => {

        let xhr:XMLHttpRequest = new XMLHttpRequest();
        xhr.onreadystatechange = () => {
            if (xhr.readyState === 4) {
                if (xhr.status === 200) {
                    resolve(<MyEntity>JSON.parse(xhr.response));
                } else {
                    reject(xhr.response);
                }
            }
        };

        xhr.open('POST', this.getServiceUrl(), true);

        let formData = new FormData();
        formData.append("file", file, file.name);
        xhr.send(formData);
    });
}

How to combine 2 plots (ggplot) into one plot?

Just combine them. I think this should work but it's untested:

p <- ggplot(visual1, aes(ISSUE_DATE,COUNTED)) + geom_point() + 
     geom_smooth(fill="blue", colour="darkblue", size=1)

p <- p + geom_point(data=visual2, aes(ISSUE_DATE,COUNTED)) + 
     geom_smooth(data=visual2, fill="red", colour="red", size=1)

print(p)

CSS background image in :after element

As AlienWebGuy said, you can use background-image. I'd suggest you use background, but it will need three more properties after the URL:

background: url("http://www.gentleface.com/i/free_toolbar_icons_16x16_black.png") 0 0 no-repeat;

Explanation: the two zeros are x and y positioning for the image; if you want to adjust where the background image displays, play around with these (you can use both positive and negative values, e.g: 1px or -1px).

No-repeat says you don't want the image to repeat across the entire background. This can also be repeat-x and repeat-y.

Could pandas use column as index?

You can set the column index using index_col parameter available while reading from spreadsheet in Pandas.

Here is my solution:

  1. Firstly, import pandas as pd: import pandas as pd

  2. Read in filename using pd.read_excel() (if you have your data in a spreadsheet) and set the index to 'Locality' by specifying the index_col parameter.

    df = pd.read_excel('testexcel.xlsx', index_col=0)

    At this stage if you get a 'no module named xlrd' error, install it using pip install xlrd.

  3. For visual inspection, read the dataframe using df.head() which will print the following output sc

  4. Now you can fetch the values of the desired columns of the dataframe and print it

    sc2

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

EDIT: This answer is correct for version 0.2.10. As @Alexander Vasilyev pointed out it doesn't work in version 0.2.14.

Another reason to use $state.params is when you need to extract query parameters like this:

$stateProvider.state('a', {
  url: 'path/:id/:anotherParam/?yetAnotherParam',
  controller: 'ACtrl',
});

module.controller('ACtrl', function($stateParams, $state) {
  $state.params; // has id, anotherParam, and yetAnotherParam
  $stateParams;  // has id and anotherParam
}

How to Refresh a Component in Angular

Just change the routeReuseStrategy from the angular Router:

this._router.routeReuseStrategy.shouldReuseRoute = function () {
      return false;
    };

Set the routerproperty "navigated" to false:

this._router.navigated = false;

Then navigate to your component:

this._router.navigate(['routeToYourComponent'])

After that reinstate the old/default routeReuseStrategy:

this._router.routeReuseStrategy.shouldReuseRoute = function (future: ActivatedRouteSnapshot, curr: ActivatedRouteSnapshot): boolean {
          return future.routeConfig === curr.routeConfig;

You can also make a service out of this:

@Injectable({
  providedIn: 'root'
})
export class RouterService {

  constructor(
    private _activatedRoute: ActivatedRoute,
    private _router: Router
  ) { }

  reuseRoutes(reuse: boolean) {
    if (!reuse) {
      this._router.routeReuseStrategy.shouldReuseRoute = function () {
        return false;
      };
    }
    if (reuse) {
      this._router.routeReuseStrategy.shouldReuseRoute = function (future: ActivatedRouteSnapshot, curr: ActivatedRouteSnapshot): boolean {
        return future.routeConfig === curr.routeConfig;
      };
    }
  }

  async refreshPage(url?: string) {
    this._router.routeReuseStrategy.shouldReuseRoute = function () {
      return false;
    };

    this._router.navigated = false;

    url ? await this._router.navigate([url]) : await this._router.navigate([], { relativeTo: this._activatedRoute });

    this._router.routeReuseStrategy.shouldReuseRoute = function (future: ActivatedRouteSnapshot, curr: ActivatedRouteSnapshot): boolean {
      return future.routeConfig === curr.routeConfig;
    };
  }
}