Programs & Examples On #Domain object

Domain Objects are objects made for dealing with the domain logic at the Model layer. These objects generally simulate real (or virtual) items from real-life: Person, Post, Document, etc.

Is there a way to pass optional parameters to a function?

def my_func(mandatory_arg, optional_arg=100):
    print(mandatory_arg, optional_arg)

http://docs.python.org/2/tutorial/controlflow.html#default-argument-values

I find this more readable than using **kwargs.

To determine if an argument was passed at all, I use a custom utility object as the default value:

MISSING = object()

def func(arg=MISSING):
    if arg is MISSING:
        ...

TSQL How do you output PRINT in a user defined function?

I have tended in the past to work on my functions in two stages. The first stage would be to treat them as fairly normal SQL queries and make sure that I am getting the right results out of it. After I am confident that it is performing as desired, then I would convert it into a UDF.

How to decode a Base64 string?

Base64 encoding converts three 8-bit bytes (0-255) into four 6-bit bytes (0-63 aka base64). Each of the four bytes indexes an ASCII string which represents the final output as four 8-bit ASCII characters. The indexed string is typically 'A-Za-z0-9+/' with '=' used as padding. This is why encoded data is 4/3 longer.

Base64 decoding is the inverse process. And as one would expect, the decoded data is 3/4 as long.

While base64 encoding can encode plain text, its real benefit is encoding non-printable characters which may be interpreted by transmitting systems as control characters.

I suggest the original poster render $z as bytes with each bit having meaning to the application. Rendering non-printable characters as text typically invokes Unicode which produces glyphs based on your system's localization.

Base64decode("the answer to life the universe and everything") = 00101010

How do I get the name of the active user via the command line in OS X?

getting username in MAC terminal is easy...

I generally use whoami in terminal...

For example, in this case, I needed that to install Tomcat Server...

enter image description here

Disable browser's back button

There have been a few different implementations. There is a flash solution and some iframe/frame solutions for IE. Check out this

http://www.contentwithstyle.co.uk/content/fixing-the-back-button-and-enabling-bookmarking-for-ajax-apps

BTW: There are plenty of valid reasons to disable (or at least prevent 1 step) a back button -- look at gmail as an example which implements the hash solution discussed in the above article.

Google "how ajax broke the back button" and you'll find plenty of articles on user testing and the validity of disabling the back button.

C# refresh DataGridView when updating or inserted on another form

Create a small function and use it anywhere

public SqlConnection con = "Your connection string"; 
public void gridviewUpdate()
{
    con.Open();
    string select = "SELECT * from table_name";
    SqlDataAdapter da = new SqlDataAdapter(select, con);
    DataSet ds = new DataSet();
    da.Fill(ds, "table_name");
    datagridview.DataSource = ds;
    datagridview.DataMember = "table_name";
    con.Close();
}

How to convert int[] into List<Integer> in Java?

In Java 8 :

int[] arr = {1,2,3};
IntStream.of(arr).boxed().collect(Collectors.toList());

Add target="_blank" in CSS

Unfortunately, no. In 2013, there is no way to do it with pure CSS.


Update: thanks to showdev for linking to the obsolete spec of CSS3 Hyperlinks, and yes, no browser has implemented it. So the answer still stands valid.

How to start working with GTest and CMake

The OP is using Windows, and a much easier way to use GTest today is with vcpkg+cmake.


Install vcpkg as per https://github.com/microsoft/vcpkg , and make sure you can run vcpkg from the cmd line. Take note of the vcpkg installation folder, eg. C:\bin\programs\vcpkg.

Install gtest using vcpkg install gtest: this will download, compile, and install GTest.

Use a CmakeLists.txt as below: note we can use targets instead of including folders.

cmake_minimum_required(VERSION 3.15)
project(sample CXX)
enable_testing()
find_package(GTest REQUIRED)
add_executable(test1 test.cpp source.cpp)
target_link_libraries(test1 GTest::GTest GTest::Main)
add_test(test-1 test1)

Run cmake with: (edit the vcpkg folder if necessary, and make sure the path to the vcpkg.cmake toolchain file is correct)

cmake -B build -DCMAKE_TOOLCHAIN_FILE=C:\bin\programs\vcpkg\scripts\buildsystems\vcpkg.cmake

and build using cmake --build build as usual. Note that, vcpkg will also copy the required gtest(d).dll/gtest(d)_main.dll from the install folder to the Debug/Release folders.

Test with cd build & ctest.

Post-increment and pre-increment within a 'for' loop produce same output

If you wrote it like this then it would matter :

for(i=0; i<5; i=j++) {
    printf("%d",i);
}

Would iterate once more than if written like this :

for(i=0; i<5; i=++j) {
    printf("%d",i);
}

How to use HTML Agility pack

HtmlAgilityPack uses XPath syntax, and though many argues that it is poorly documented, I had no trouble using it with help from this XPath documentation: https://www.w3schools.com/xml/xpath_syntax.asp

To parse

<h2>
  <a href="">Jack</a>
</h2>
<ul>
  <li class="tel">
    <a href="">81 75 53 60</a>
  </li>
</ul>
<h2>
  <a href="">Roy</a>
</h2>
<ul>
  <li class="tel">
    <a href="">44 52 16 87</a>
  </li>
</ul>

I did this:

string url = "http://website.com";
var Webget = new HtmlWeb();
var doc = Webget.Load(url);
foreach (HtmlNode node in doc.DocumentNode.SelectNodes("//h2//a"))
{
  names.Add(node.ChildNodes[0].InnerHtml);
}
foreach (HtmlNode node in doc.DocumentNode.SelectNodes("//li[@class='tel']//a"))
{
  phones.Add(node.ChildNodes[0].InnerHtml);
}

Rails 4: how to use $(document).ready() with turbo-links

NOTE: See @SDP's answer for a clean, built-in solution

I fixed it as follows:

make sure you include application.js before the other app dependent js files get included by changing the include order as follows:

// in application.js - make sure `require_self` comes before `require_tree .`
//= require_self
//= require_tree .

Define a global function that handles the binding in application.js

// application.js
window.onLoad = function(callback) {
  // binds ready event and turbolink page:load event
  $(document).ready(callback);
  $(document).on('page:load',callback);
};

Now you can bind stuff like:

// in coffee script:
onLoad ->
  $('a.clickable').click => 
    alert('link clicked!');

// equivalent in javascript:
onLoad(function() {
  $('a.clickable').click(function() {
    alert('link clicked');
});

How to log out user from web site using BASIC authentication?

This is working for IE/Netscape/Chrome :

      function ClearAuthentication(LogOffPage) 
  {
     var IsInternetExplorer = false;    

     try
     {
         var agt=navigator.userAgent.toLowerCase();
         if (agt.indexOf("msie") != -1) { IsInternetExplorer = true; }
     }
     catch(e)
     {
         IsInternetExplorer = false;    
     };

     if (IsInternetExplorer) 
     {
        // Logoff Internet Explorer
        document.execCommand("ClearAuthenticationCache");
        window.location = LogOffPage;
     }
     else 
     {
        // Logoff every other browsers
    $.ajax({
         username: 'unknown',
         password: 'WrongPassword',
             url: './cgi-bin/PrimoCgi',
         type: 'GET',
         beforeSend: function(xhr)
                 {
            xhr.setRequestHeader("Authorization", "Basic AAAAAAAAAAAAAAAAAAA=");
         },

                 error: function(err)
                 {
                    window.location = LogOffPage;
             }
    });
     }
  }


  $(document).ready(function () 
  {
      $('#Btn1').click(function () 
      {
         // Call Clear Authentication 
         ClearAuthentication("force_logout.html"); 
      });
  });          

Android Button click go to another xml page

Write below code in your MainActivity.java file instead of your code.

public class MainActivity extends Activity implements OnClickListener {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button mBtn1 = (Button) findViewById(R.id.mBtn1);
        mBtn1.setOnClickListener(this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    @Override
    public void onClick(View v) {
        Log.i("clicks","You Clicked B1");
        Intent i=new Intent(MainActivity.this, MainActivity2.class);
        startActivity(i);
    }
}

And Declare MainActivity2 into your Androidmanifest.xml file using below code.

<activity
    android:name=".MainActivity2"
    android:label="@string/title_activity_main">
</activity>

Assigning more than one class for one event

    $('.tag1, .tag2').on('click', function() {

      if ($(this).hasClass('clickedTag')){
         // code here
      } else {
         // and here
      }

   });

or

function dothing() {
   if ($(this).hasClass('clickedTag')){
        // code here
    } else {
        // and here
   }
}

$('.tag1, .tag2').on('click', dothing);

or

 $('[class^=tag]').on('click', dothing);

How do I drag and drop files into an application?

You can implement Drag&Drop in WinForms and WPF.

  • WinForm (Drag from app window)

You should add mousemove event:

private void YourElementControl_MouseMove(object sender, MouseEventArgs e)

    {
     ...
         if (e.Button == MouseButtons.Left)
         {
                 DoDragDrop(new DataObject(DataFormats.FileDrop, new string[] { PathToFirstFile,PathToTheNextOne }), DragDropEffects.Move);
         }
     ...
    }
  • WinForm (Drag to app window)

You should add DragDrop event:

private void YourElementControl_DragDrop(object sender, DragEventArgs e)

    {
       ...
       foreach (string path in (string[])e.Data.GetData(DataFormats.FileDrop))
            {
                File.Copy(path, DirPath + Path.GetFileName(path));
            }
       ...
    }

Source with full code.

How to export data as CSV format from SQL Server using sqlcmd?

An answer above almost solved it for me but it does not correctly create a parsed CSV.

Here's my version:

sqlcmd -S myurl.com -d MyAzureDB -E -s, -W -i mytsql.sql | findstr /V /C:"-" /B > parsed_correctly.csv

Someone saying that sqlcmd is outdated in favor of some PowerShell alternative is forgetting that sqlcmd isn't just for Windows. I'm on Linux (and when on Windows I avoid PS anyway).

Having said all that, I do find bcp easier.

Adding and removing style attribute from div with jquery

You could do any of the following

Set each style property individually:

$("#voltaic_holder").css("position", "relative");

Set multiple style properties at once:

$("#voltaic_holder").css({"position":"relative", "top":"-75px"});

Remove a specific style:

$("#voltaic_holder").css({"top": ""});
// or
$("#voltaic_holder").css("top", "");

Remove the entire style attribute:

$("#voltaic_holder").removeAttr("style")

How can you flush a write using a file descriptor?

If you want to go the other way round (associate FILE* with existing file descriptor), use fdopen() :

                                                          FDOPEN(P)

NAME

       fdopen - associate a stream with a file descriptor

SYNOPSIS

       #include <stdio.h>

       FILE *fdopen(int fildes, const char *mode);

How to get input textfield values when enter key is pressed in react js?

html

<input id="something" onkeyup="key_up(this)" type="text">

script

function key_up(e){
    var enterKey = 13; //Key Code for Enter Key
    if (e.which == enterKey){
        //Do you work here
    }
}

Next time, Please try providing some code.

When saving, how can you check if a field has changed?

Since Django 1.8 released, you can use from_db classmethod to cache old value of remote_image. Then in save method you can compare old and new value of field to check if the value has changed.

@classmethod
def from_db(cls, db, field_names, values):
    new = super(Alias, cls).from_db(db, field_names, values)
    # cache value went from the base
    new._loaded_remote_image = values[field_names.index('remote_image')]
    return new

def save(self, force_insert=False, force_update=False, using=None,
         update_fields=None):
    if (self._state.adding and self.remote_image) or \
        (not self._state.adding and self._loaded_remote_image != self.remote_image):
        # If it is first save and there is no cached remote_image but there is new one, 
        # or the value of remote_image has changed - do your stuff!

How can I use UserDefaults in Swift?

Swift 4, I have used Enum for handling UserDefaults.

This is just a sample code. You can customize it as per your requirements.

For Storing, Retrieving, Removing. In this way just add a key for your UserDefaults key to the enum. Handle values while getting and storing according to dataType and your requirements.

enum UserDefaultsConstant : String {
    case AuthToken, FcmToken

    static let defaults = UserDefaults.standard


   //Store
    func setValue(value : Any) {
        switch self {
        case .AuthToken,.FcmToken:
            if let _ = value as? String {
                UserDefaults.standard.set(value, forKey: self.rawValue)
            }
            break
        }

        UserDefaults.standard.synchronize()
    }

   //Retrieve
    func getValue() -> Any? {
        switch self {
        case .AuthToken:
            if(UserDefaults.standard.value(forKey: UserDefaultsConstant.AuthToken.rawValue) != nil) {

                return "Bearer "+(UserDefaults.standard.value(forKey: UserDefaultsConstant.AuthToken.rawValue) as! String)
            }
            else {
                return ""
            }

        case .FcmToken:

            if(UserDefaults.standard.value(forKey: UserDefaultsConstant.FcmToken.rawValue) != nil) {
                print(UserDefaults.standard.value(forKey: UserDefaultsConstant.FcmToken.rawValue))
                return (UserDefaults.standard.value(forKey: UserDefaultsConstant.FcmToken.rawValue) as! String)
            }
            else {
                return ""
            }
        }
    }

    //Remove
    func removeValue() {
        UserDefaults.standard.removeObject(forKey: self.rawValue)
        UserDefaults.standard.synchronize()
    }
}

For storing a value in userdefaults,

if let authToken = resp.data?.token {
     UserDefaultsConstant.AuthToken.setValue(value: authToken)
    }

For retrieving a value from userdefaults,

//As AuthToken value is a string
    (UserDefaultsConstant.AuthToken.getValue() as! String)

Bizarre Error in Chrome Developer Console - Failed to load resource: net::ERR_CACHE_MISS

See if you can recreate the issue in an Incognito tab. If you find that the problem no longer occurs then I would recommend you go through your extensions, perhaps disabling them one at a time. This is commonly the cause as touched on by Nikola

How to get disk capacity and free space of remote computer

$disk = Get-WmiObject Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Select-Object Size,FreeSpace

$disk.Size
$disk.FreeSpace

To extract the values only and assign them to a variable:

$disk = Get-WmiObject Win32_LogicalDisk -ComputerName remotecomputer -Filter "DeviceID='C:'" |
Foreach-Object {$_.Size,$_.FreeSpace}

Ifelse statement in R with multiple conditions

another solution using dplyr is:

df <- ## your data ##
df <- df %>%
        mutate(Den = ifelse(any(is.na(Den)) | any(Den != 1), 0, 1))

How to programmatically disable page scrolling with jQuery

This may or may not work for your purposes, but you can extend jScrollPane to fire other functionality before it does its scrolling. I've only just tested this a little bit, but I can confirm that you can jump in and prevent the scrolling entirely. All I did was:

  • Download the demo zip: http://github.com/vitch/jScrollPane/archives/master
  • Open the "Events" demo (events.html)
  • Edit it to use the non-minified script source: <script type="text/javascript" src="script/jquery.jscrollpane.js"></script>
  • Within jquery.jscrollpane.js, insert a "return;" at line 666 (auspicious line number! but in case your version differs slightly, this is the first line of the positionDragY(destY, animate) function

Fire up events.html, and you'll see a normally scrolling box which due to your coding intervention won't scroll.

You can control the entire browser's scrollbars this way (see fullpage_scroll.html).

So, presumably the next step is to add a call to some other function that goes off and does your anchoring magic, then decides whether to continue with the scroll or not. You've also got API calls to set scrollTop and scrollLeft.

If you want more help, post where you get up to!

Hope this has helped.

What is @ModelAttribute in Spring MVC?

@ModelAttribute refers to a property of the Model object (the M in MVC ;) so let's say we have a form with a form backing object that is called "Person" Then you can have Spring MVC supply this object to a Controller method by using the @ModelAttribute annotation:

public String processForm(@ModelAttribute("person") Person person){
    person.getStuff();
}

On the other hand the annotation is used to define objects which should be part of a Model. So if you want to have a Person object referenced in the Model you can use the following method:

@ModelAttribute("person")
public Person getPerson(){
    return new Person();
}

This annotated method will allow access to the Person object in your View, since it gets automatically added to the Models by Spring.

See "Using @ModelAttribute".

Qt jpg image display

I want to display .jpg image in an Qt UI

The simpliest way is to use QLabel for this:

int main(int argc, char *argv[]) {
    QApplication a(argc, argv);
    QLabel label("<img src='image.jpg' />");
    label.show();
    return a.exec();
}

Spring: How to get parameters from POST body?

You can bind the json to a POJO using MappingJacksonHttpMessageConverter . Thus your controller signature can read :-

  public ResponseEntity<Boolean> saveData(@RequestBody RequestDTO req) 

Where RequestDTO needs to be a bean appropriately annotated to work with jackson serializing/deserializing. Your *-servlet.xml file should have the Jackson message converter registered in RequestMappingHandler as follows :-

  <list >
    <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"/>

  </list>
</property>
</bean>

Android Pop-up message

Use This And Call This In OnCreate Method In Which Activity You Want

public void popupMessage(){
        AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
        alertDialogBuilder.setMessage("No Internet Connection. Check Your Wifi Or enter code hereMobile Data.");
        alertDialogBuilder.setIcon(R.drawable.ic_no_internet);
        alertDialogBuilder.setTitle("Connection Failed");
        alertDialogBuilder.setNegativeButton("ok", new DialogInterface.OnClickListener(){

            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                Log.d("internet","Ok btn pressed");
                finishAffinity();
                System.exit(0);
            }
        });
        AlertDialog alertDialog = alertDialogBuilder.create();
        alertDialog.show();
    }

Get and Set a Single Cookie with Node.js HTTP Server

There is no quick function access to getting/setting cookies, so I came up with the following hack:

var http = require('http');

function parseCookies (request) {
    var list = {},
        rc = request.headers.cookie;

    rc && rc.split(';').forEach(function( cookie ) {
        var parts = cookie.split('=');
        list[parts.shift().trim()] = decodeURI(parts.join('='));
    });

    return list;
}


http.createServer(function (request, response) {

  // To Read a Cookie
  var cookies = parseCookies(request);

  // To Write a Cookie
  response.writeHead(200, {
    'Set-Cookie': 'mycookie=test',
    'Content-Type': 'text/plain'
  });
  response.end('Hello World\n');
}).listen(8124);

console.log('Server running at http://127.0.0.1:8124/');

This will store all cookies into the cookies object, and you need to set cookies when you write the head.

Number format in excel: Showing % value without multiplying with 100

Be aware that a value of 1 equals 100% in Excel's interpretation. If you enter 5.66 and you want to show 5.66%, then AxGryndr's hack with the formatting will work, but it is a display format only and does not represent the true numeric value. If you want to use that percentage in further calculations, these calculations will return the wrong result unless you divide by 100 at calculation time.

The consistent and less error-prone way is to enter 0.0566 and format the number with the built-in percentage format. That way, you can easily calculate 5.6% of A1 by just multiplying A1 with the value.

The good news is that you don't need to go through the rigmarole of entering 0.0566 and then formatting as percent. You can simply type

5.66%

into the cell, including the percentage symbol, and Excel will take care of the rest and store the number correctly as 0.0566 if formatted as General.

pip: no module named _internal

This issue maybe due to common user do not have privilege to access packages py file.
1. root user can run 'pip list'
2. other common user cannot run 'pip list'

[~]$ pip list
Traceback (most recent call last):
  File "/usr/bin/pip", line 7, in <module>
from pip._internal import main
ImportError: No module named pip._internal

Check pip py file privilege.

[root@]# ll /usr/lib/python2.7/site-packages/pip/  
?? 24  
-rw-------  1 root root   24  6?  7 16:57 __init__.py  
-rw-------  1 root root  163  6?  7 16:57 __init__.pyc  
-rw-------  1 root root  629  6?  7 16:57 __main__.py  
-rw-------  1 root root  510  6?  7 16:57 __main__.pyc  
drwx------  8 root root 4096  6?  7 16:57 _internal  
drwx------ 18 root root 4096  6?  7 16:57 _vendor  

solution : root user login and run

chmod -R 755 /usr/lib/python2.7 

fix this issue.

What is the difference between a static and a non-static initialization code block

when a developer use an initializer block, the Java Compiler copies the initializer into each constructor of the current class.

Example:

the following code:

class MyClass {

    private int myField = 3;
    {
        myField = myField + 2;
        //myField is worth 5 for all instance
    }

    public MyClass() {
        myField = myField * 4;
        //myField is worth 20 for all instance initialized with this construtor
    }

    public MyClass(int _myParam) {
        if (_myParam > 0) {
            myField = myField * 4;
            //myField is worth 20 for all instance initialized with this construtor
            //if _myParam is greater than 0
        } else {
            myField = myField + 5;
            //myField is worth 10 for all instance initialized with this construtor
            //if _myParam is lower than 0 or if _myParam is worth 0
        }
    }

    public void setMyField(int _myField) {
        myField = _myField;
    }


    public int getMyField() {
        return myField;
    }
}

public class MainClass{

    public static void main(String[] args) {
        MyClass myFirstInstance_ = new MyClass();
        System.out.println(myFirstInstance_.getMyField());//20
        MyClass mySecondInstance_ = new MyClass(1);
        System.out.println(mySecondInstance_.getMyField());//20
        MyClass myThirdInstance_ = new MyClass(-1);
        System.out.println(myThirdInstance_.getMyField());//10
    }
}

is equivalent to:

class MyClass {

    private int myField = 3;

    public MyClass() {
        myField = myField + 2;
        myField = myField * 4;
        //myField is worth 20 for all instance initialized with this construtor
    }

    public MyClass(int _myParam) {
        myField = myField + 2;
        if (_myParam > 0) {
            myField = myField * 4;
            //myField is worth 20 for all instance initialized with this construtor
            //if _myParam is greater than 0
        } else {
            myField = myField + 5;
            //myField is worth 10 for all instance initialized with this construtor
            //if _myParam is lower than 0 or if _myParam is worth 0
        }
    }

    public void setMyField(int _myField) {
        myField = _myField;
    }


    public int getMyField() {
        return myField;
    }
}

public class MainClass{

    public static void main(String[] args) {
        MyClass myFirstInstance_ = new MyClass();
        System.out.println(myFirstInstance_.getMyField());//20
        MyClass mySecondInstance_ = new MyClass(1);
        System.out.println(mySecondInstance_.getMyField());//20
        MyClass myThirdInstance_ = new MyClass(-1);
        System.out.println(myThirdInstance_.getMyField());//10
    }
}

I hope my example is understood by developers.

no suitable HttpMessageConverter found for response type

This is not answering the problem but if anyone comes to this question when they stumble upon this exception of no suitable message converter found, here is my problem and solution.

In Spring 4.0.9, we were able to send this

    JSONObject jsonCredential = new JSONObject();
    jsonCredential.put(APPLICATION_CREDENTIALS, data);

    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(MediaType.APPLICATION_JSON);

ResponseEntity<String> res = restTemplate.exchange(myRestUrl), HttpMethod.POST,request, String.class);

In Spring 4.3.5 release, we starting seeing errors with the message that converter was not found.

The way Convertors work is that if you have it in your classpath, they get registered.

Jackson-asl was still in classpath but was not being recognized by spring. We replaced Jackson-asl with faster-xml jackson core.

Once we added I could see the converter being registered.

enter image description here

Handling the null value from a resultset in JAVA

The description of the getString() method says the following:

 the column value; if the value is SQL NULL, the value returned is null

That means your problem is not that the String value is null, rather some other object is, perhaps your ResultSet or maybe you closed the connection or something like this. Provide the stack trace, that would help.

Maven Java EE Configuration Marker with Java Server Faces 1.2

the same solution as Basit .. but the version 3.0 doesn't work for me try this .. it works for me to integrate struts 2.x

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
    <display-name>blabla</display-name>
...
</web-app>

printing all contents of array in C#

Due to having some downtime at work, I decided to test the speeds of the different methods posted here.

These are the four methods I used.

static void Print1(string[] toPrint)
{
    foreach(string s in toPrint)
    {
        Console.Write(s);
    }
}

static void Print2(string[] toPrint)
{
    toPrint.ToList().ForEach(Console.Write);
}

static void Print3(string[] toPrint)
{
    Console.WriteLine(string.Join("", toPrint));
}

static void Print4(string[] toPrint)
{
    Array.ForEach(toPrint, Console.Write);
}

The results are as follows:

 Strings per trial: 10000
 Number of Trials: 100
 Total Time Taken to complete: 00:01:20.5004836
 Print1 Average: 484.37ms
 Print2 Average: 246.29ms
 Print3 Average: 70.57ms
 Print4 Average: 233.81ms

So Print3 is the fastest, because it only has one call to the Console.WriteLine which seems to be the main bottleneck for the speed of printing out an array. Print4 is slightly faster than Print2 and Print1 is the slowest of them all.

I think that Print4 is probably the most versatile of the 4 I tested, even though Print3 is faster.

If I made any errors, feel free to let me know / fix them on your own!

EDIT: I'm adding the generated IL below

g__Print10_0://Print1
IL_0000:  ldarg.0     
IL_0001:  stloc.0     
IL_0002:  ldc.i4.0    
IL_0003:  stloc.1     
IL_0004:  br.s        IL_0012
IL_0006:  ldloc.0     
IL_0007:  ldloc.1     
IL_0008:  ldelem.ref  
IL_0009:  call        System.Console.Write
IL_000E:  ldloc.1     
IL_000F:  ldc.i4.1    
IL_0010:  add         
IL_0011:  stloc.1     
IL_0012:  ldloc.1     
IL_0013:  ldloc.0     
IL_0014:  ldlen       
IL_0015:  conv.i4     
IL_0016:  blt.s       IL_0006
IL_0018:  ret         

g__Print20_1://Print2
IL_0000:  ldarg.0     
IL_0001:  call        System.Linq.Enumerable.ToList<String>
IL_0006:  ldnull      
IL_0007:  ldftn       System.Console.Write
IL_000D:  newobj      System.Action<System.String>..ctor
IL_0012:  callvirt    System.Collections.Generic.List<System.String>.ForEach
IL_0017:  ret         

g__Print30_2://Print3
IL_0000:  ldstr       ""
IL_0005:  ldarg.0     
IL_0006:  call        System.String.Join
IL_000B:  call        System.Console.WriteLine
IL_0010:  ret         

g__Print40_3://Print4
IL_0000:  ldarg.0     
IL_0001:  ldnull      
IL_0002:  ldftn       System.Console.Write
IL_0008:  newobj      System.Action<System.String>..ctor
IL_000D:  call        System.Array.ForEach<String>
IL_0012:  ret   

Get current time in milliseconds using C++ and Boost

You can use boost::posix_time::time_duration to get the time range. E.g like this

boost::posix_time::time_duration diff = tick - now;
diff.total_milliseconds();

And to get a higher resolution you can change the clock you are using. For example to the boost::posix_time::microsec_clock, though this can be OS dependent. On Windows, for example, boost::posix_time::microsecond_clock has milisecond resolution, not microsecond.

An example which is a little dependent on the hardware.

int main(int argc, char* argv[])
{
    boost::posix_time::ptime t1 = boost::posix_time::second_clock::local_time();
    boost::this_thread::sleep(boost::posix_time::millisec(500));
    boost::posix_time::ptime t2 = boost::posix_time::second_clock::local_time();
    boost::posix_time::time_duration diff = t2 - t1;
    std::cout << diff.total_milliseconds() << std::endl;

    boost::posix_time::ptime mst1 = boost::posix_time::microsec_clock::local_time();
    boost::this_thread::sleep(boost::posix_time::millisec(500));
    boost::posix_time::ptime mst2 = boost::posix_time::microsec_clock::local_time();
    boost::posix_time::time_duration msdiff = mst2 - mst1;
    std::cout << msdiff.total_milliseconds() << std::endl;
    return 0;
}

On my win7 machine. The first out is either 0 or 1000. Second resolution. The second one is nearly always 500, because of the higher resolution of the clock. I hope that help a little.

Initializing C dynamic arrays

p = {1,2,3} is wrong.

You can never use this:

int * p;
p = {1,2,3};

loop is right

int *p,i;
p = malloc(3*sizeof(int));
for(i = 0; i<3; ++i)
    p[i] = i;

What is a elegant way in Ruby to tell if a variable is a Hash or an Array?

I use this:

@var.respond_to?(:keys)

It works for Hash and ActiveSupport::HashWithIndifferentAccess.

Display a tooltip over a button using Windows Forms

Using the form designer:

  • Drag the ToolTip control from the Toolbox, onto the form.
  • Select the properties of the control you want the tool tip to appear on.
  • Find the property 'ToolTip on toolTip1' (the name may not be toolTip1 if you changed it's default name).
  • Set the text of the property to the tool tip text you would like to display.

You can set also the tool tip programatically using the following call:

this.toolTip1.SetToolTip(this.targetControl, "My Tool Tip");

JPA: how do I persist a String into a database field, type MYSQL Text

for mysql 'text':

@Column(columnDefinition = "TEXT")
private String description;

for mysql 'longtext':

@Lob
private String description;

How to access site running apache server over lan without internet connection

  1. navigate to C:\wamp\alias.
  2. make file with project name and like phpmyadmin.conf
  3. add the following section and change :

    Options Indexes FollowSymLinks MultiViews AllowOverride all Order Deny,Allow Allow from all

change directory to your directory path like c:\wamp\www\projectfolder

  1. make sure you make the same in httpd.conf for all directory like first directory:

    Options Indexes FollowSymLinks AllowOverride All Order allow,deny Allow from all

second directory:

<Directory "c:/wamp/www/">

#
# Possible values for the Options directive are "None", "All",
# or any combination of:
#   Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews
#
# Note that "MultiViews" must be named *explicitly* --- "Options All"
# doesn't give it to you.
#
# The Options directive is both complicated and important.  Please see
# http://httpd.apache.org/docs/2.0/mod/core.html#options
# for more information.
#
    Options Indexes FollowSymLinks

#
# AllowOverride controls what directives may be placed in .htaccess files.
# It can be "All", "None", or any combination of the keywords:
#   Options FileInfo AuthConfig Limit
#
    AllowOverride all

#
# Controls who can get stuff from this server.
#

#   onlineoffline tag - don't remove
    Order Deny,Allow
    Allow from all

</Directory>

<Directory "icons">
    Options Indexes MultiViews
    AllowOverride None
    Order allow,deny
    Allow from all
</Directory>

Programmatically switching between tabs within Swift

In a typical application there is a UITabBarController and it embeds 3 or more UIViewController as its tabs. In such a case if you subclassed a UITabBarController as YourTabBarController then you can set the selected index simply by:

selectedIndex = 1 // Displays 2nd tab. The index starts from 0.

In case you are navigating to YourTabBarController from any other view, then in that view controller's prepare(for segue:) method you can do:

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        // Get the new view controller using segue.destination.
        // Pass the selected object to the new view controller.
        if segue.identifier == "SegueToYourTabBarController" {
            if let destVC = segue.destination as? YourTabBarController {
                destVC.selectedIndex = 0
            }
        }

I am using this way of setting tab with Xcode 10 and Swift 4.2.

R multiple conditions in if statement

Read this thread R - boolean operators && and ||.

Basically, the & is vectorized, i.e. it acts on each element of the comparison returning a logical array with the same dimension as the input. && is not, returning a single logical.

.htaccess redirect http to https

Replace your domain with domainname.com , it's working with me .

RewriteEngine On
RewriteCond %{HTTP_HOST} ^domainname\.com [NC]
RewriteCond %{SERVER_PORT} 80
RewriteRule ^(.*)$ https://www.domainname.com/$1 [R,L]

Does Hive have a String split function?

Just a clarification on the answer given by Bkkbrad.

I tried this suggestion and it did not work for me.

For example,

split('aa|bb','\\|')

produced:

["","a","a","|","b","b",""]

But,

split('aa|bb','[|]')

produced the desired result:

["aa","bb"]

Including the metacharacter '|' inside the square brackets causes it to be interpreted literally, as intended, rather than as a metacharacter.

For elaboration of this behaviour of regexp, see: http://www.regular-expressions.info/charclass.html

Floating point comparison functions for C#

Here's how I solved it, with nullable double extension method.

    public static bool NearlyEquals(this double? value1, double? value2, double unimportantDifference = 0.0001)
    {
        if (value1 != value2)
        {
            if(value1 == null || value2 == null)
                return false;

            return Math.Abs(value1.Value - value2.Value) < unimportantDifference;
        }

        return true;
    }

...

        double? value1 = 100;
        value1.NearlyEquals(100.01); // will return false
        value1.NearlyEquals(100.000001); // will return true
        value1.NearlyEquals(100.01, 0.1); // will return true

How to check if a string contains an element from a list in Python

This is a variant of the list comprehension answer given by @psun.

By switching the output value, you can actually extract the matching pattern from the list comprehension (something not possible with the any() approach by @Lauritz-v-Thaulow)

extensionsToCheck = ['.pdf', '.doc', '.xls']
url_string = 'http://.../foo.doc'

print [extension for extension in extensionsToCheck if(extension in url_string)]

['.doc']`

You can furthermore insert a regular expression if you want to collect additional information once the matched pattern is known (this could be useful when the list of allowed patterns is too long to write into a single regex pattern)

print [re.search(r'(\w+)'+extension, url_string).group(0) for extension in extensionsToCheck if(extension in url_string)]

['foo.doc']

Why doesn't file_get_contents work?

If it is a local file, you have to wrap it in htmlspecialchars like so:

    $myfile = htmlspecialchars(file_get_contents($file_name));

Then it works

How can I determine the character encoding of an excel file?

For Excel 2010 it should be UTF-8. Instruction by MS :
http://msdn.microsoft.com/en-us/library/bb507946:

"The basic document structure of a SpreadsheetML document consists of the Sheets and Sheet elements, which reference the worksheets in the Workbook. A separate XML file is created for each Worksheet. For example, the SpreadsheetML for a workbook that has two worksheets name MySheet1 and MySheet2 is located in the Workbook.xml file and is shown in the following code example.

<?xml version="1.0" encoding="UTF-8" standalone="yes" ?> 
<workbook xmlns=http://schemas.openxmlformats.org/spreadsheetml/2006/main xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">
    <sheets>
        <sheet name="MySheet1" sheetId="1" r:id="rId1" /> 
        <sheet name="MySheet2" sheetId="2" r:id="rId2" /> 
    </sheets>
</workbook>

The worksheet XML files contain one or more block level elements such as SheetData. sheetData represents the cell table and contains one or more Row elements. A row contains one or more Cell elements. Each cell contains a CellValue element that represents the value of the cell. For example, the SpreadsheetML for the first worksheet in a workbook, that only has the value 100 in cell A1, is located in the Sheet1.xml file and is shown in the following code example.

<?xml version="1.0" encoding="UTF-8" ?> 
<worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main">
    <sheetData>
        <row r="1">
            <c r="A1">
                <v>100</v> 
            </c>
        </row>
    </sheetData>
</worksheet>

"

Detection of cell encodings:

https://metacpan.org/pod/Spreadsheet::ParseExcel::Cell

http://forums.asp.net/t/1608228.aspx/1

Spring Data and Native Query with pagination

This worked for me (I am using Postgres) in Groovy:

@RestResource(path="namespaceAndNameAndRawStateContainsMostRecentVersion", rel="namespaceAndNameAndRawStateContainsMostRecentVersion")
    @Query(nativeQuery=true,
            countQuery="""
            SELECT COUNT(1) 
            FROM 
            (
                SELECT
                ROW_NUMBER() OVER (
                    PARTITION BY name, provider_id, state
                    ORDER BY version DESC) version_partition,
                *
                FROM mydb.mytable
                WHERE
                (name ILIKE ('%' || :name || '%') OR (:name = '')) AND
                (namespace ILIKE ('%' || :namespace || '%') OR (:namespace = '')) AND
                (state = :state OR (:state = ''))
            ) t
            WHERE version_partition = 1
            """,
            value="""
            SELECT id, version, state, name, internal_name, namespace, provider_id, config, create_date, update_date 
            FROM 
            (
                SELECT 
                ROW_NUMBER() OVER (
                    PARTITION BY name, provider_id, state
                    ORDER BY version DESC) version_partition,
                *
                FROM mydb.mytable
                WHERE 
                (name ILIKE ('%' || :name || '%') OR (:name = '')) AND
                (namespace ILIKE ('%' || :namespace || '%') OR (:namespace = '')) AND
                (state = :state OR (:state = ''))       
            ) t            
            WHERE version_partition = 1             
            /*#{#pageable}*/
            """)
    public Page<Entity> findByNamespaceContainsAndNameContainsAndRawStateContainsMostRecentVersion(@Param("namespace")String namespace, @Param("name")String name, @Param("state")String state, Pageable pageable)

The key here was to use: /*#{#pageable}*/

It allows me to do sorting and pagination. You can test it by using something like this: http://localhost:8080/api/v1/entities/search/namespaceAndNameAndRawStateContainsMostRecentVersion?namespace=&name=&state=published&page=0&size=3&sort=name,desc

Watch out for this issue: Spring Pageable does not translate @Column name

How to assign a value to a TensorFlow variable?

You can also assign a new value to a tf.Variable without adding an operation to the graph: tf.Variable.load(value, session). This function can also save you adding placeholders when assigning a value from outside the graph and it is useful in case the graph is finalized.

import tensorflow as tf
x = tf.Variable(0)
sess = tf.Session()
sess.run(tf.global_variables_initializer())
print(sess.run(x))  # Prints 0.
x.load(1, sess)
print(sess.run(x))  # Prints 1.

Update: This is depricated in TF2 as eager execution is default and graphs are no longer exposed in the user-facing API.

Programmatically Add CenterX/CenterY Constraints

The ObjectiveC equivalent is:

    myView.translatesAutoresizingMaskIntoConstraints = NO;

    [[myView.centerXAnchor constraintEqualToAnchor:self.view.centerXAnchor] setActive:YES];

    [[myView.centerYAnchor constraintEqualToAnchor:self.view.centerYAnchor] setActive:YES];

How to output only captured groups with sed?

Sed has up to nine remembered patterns but you need to use escaped parentheses to remember portions of the regular expression.

See here for examples and more detail

Create XML in Javascript

Simply use

var xmlString = '<?xml version="1.0" ?><root />';
var xml = jQuery.parseXML(xml);

It's jQuery.parseXML, so no need to worry about cross-browser tricks. Use jQuery as like HTML, it's using the native XML engine.

Use index in pandas to plot data

Try this,

monthly_mean.plot(y='A', use_index=True)

Repository Pattern Step by Step Explanation

This is a nice example: The Repository Pattern Example in C#

Basically, repository hides the details of how exactly the data is being fetched/persisted from/to the database. Under the covers:

  • for reading, it creates the query satisfying the supplied criteria and returns the result set
  • for writing, it issues the commands necessary to make the underlying persistence engine (e.g. an SQL database) save the data

How to execute a Python script from the Django shell?

runscript from django-extensions

python manage.py runscript scripty.py

A sample script.py to test it out:

from django.contrib.auth.models import User
print(User.objects.values())

Mentioned at: http://django-extensions.readthedocs.io/en/latest/command_extensions.html and documented at:

python manage.py runscript --help

There is a tutorial too.

Tested on Django 1.9.6, django-extensions 1.6.7.

jQuery if statement, syntax

To add to what the others are saying, A and B can be function calls as well that return boolean values. If A returns false then B would never be called.

if (A() && B()) {
    // if A() returns false then B() is never called...
}

Error Code: 1062. Duplicate entry '1' for key 'PRIMARY'

The main reason why the error has been generated is because there is already an existing value of 1 for the column ID in which you define it as PRIMARY KEY (values are unique) in the table you are inserting.

Why not set the column ID as AUTO_INCREMENT?

CREATE  TABLE IF NOT EXISTS `PROGETTO`.`UFFICIO-INFORMAZIONI` (
  `ID` INT(11) NOT NULL AUTO_INCREMENT,
  `viale` VARCHAR(45) NULL ,
   .....

and when you are inserting record, you can now skip the column ID

INSERT INTO `PROGETTO`.`UFFICIO-INFORMAZIONI` (`viale`, `num_civico`, ...) 
VALUES ('Viale Cogel ', '120', ...)

How to get input text length and validate user in javascript

JavaScript validation is not secure as anybody can change what your script does in the browser. Using it for enhancing the visual experience is ok though.

var textBox = document.getElementById("myTextBox");
var textLength = textBox.value.length;
if(textLength > 5)
{
    //red
    textBox.style.backgroundColor = "#FF0000";
}
else
{
    //green
    textBox.style.backgroundColor = "#00FF00";
}

What is the purpose of global.asax in asp.net

The root directory of a web application has a special significance and certain content can be present on in that folder. It can have a special file called as “Global.asax”. ASP.Net framework uses the content in the global.asax and creates a class at runtime which is inherited from HttpApplication. During the lifetime of an application, ASP.NET maintains a pool of Global.asax derived HttpApplication instances. When an application receives an http request, the ASP.Net page framework assigns one of these instances to process that request. That instance is responsible for managing the entire lifetime of the request it is assigned to and the instance can only be reused after the request has been completed when it is returned to the pool. The instance members in Global.asax cannot be used for sharing data across requests but static member can be. Global.asax can contain the event handlers of HttpApplication object and some other important methods which would execute at various points in a web application

$(...).datepicker is not a function - JQuery - Bootstrap

 <script type="text/javascript">

    var options={
            format: 'mm/dd/yyyy',
            todayHighlight: true,
            autoclose: true,
        };

    $('#datetimepicker').datepicker(options);

</script>

How to minify php page html output?

CSS and Javascript

Consider the following link to minify Javascript/CSS files: https://github.com/mrclay/minify

HTML

Tell Apache to deliver HTML with GZip - this generally reduces the response size by about 70%. (If you use Apache, the module configuring gzip depends on your version: Apache 1.3 uses mod_gzip while Apache 2.x uses mod_deflate.)

Accept-Encoding: gzip, deflate

Content-Encoding: gzip

Use the following snippet to remove white-spaces from the HTML with the help ob_start's buffer:

<?php

function sanitize_output($buffer) {

    $search = array(
        '/\>[^\S ]+/s',     // strip whitespaces after tags, except space
        '/[^\S ]+\</s',     // strip whitespaces before tags, except space
        '/(\s)+/s',         // shorten multiple whitespace sequences
        '/<!--(.|\s)*?-->/' // Remove HTML comments
    );

    $replace = array(
        '>',
        '<',
        '\\1',
        ''
    );

    $buffer = preg_replace($search, $replace, $buffer);

    return $buffer;
}

ob_start("sanitize_output");

?>

How to select top n rows from a datatable/dataview in ASP.NET

Data view is good Feature of data table . We can filter the data table as per our requirements using data view . Below Functions is After binding data table to list box data source then filter by text box control . ( this condition you can change as per your needs .Contains(txtSearch.Text.Trim()) )

Private Sub BindClients()

   okcl = 0

    sql = "Select * from Client Order By cname"        
    Dim dacli As New SqlClient.SqlDataAdapter
    Dim cmd As New SqlClient.SqlCommand()
    cmd.CommandText = sql
    cmd.CommandType = CommandType.Text
    dacli.SelectCommand = cmd
    dacli.SelectCommand.Connection = Me.sqlcn
    Dim dtcli As New DataTable
    dacli.Fill(dtcli)
    dacli.Fill(dataTableClients)
    lstboxc.DataSource = dataTableClients
    lstboxc.DisplayMember = "cname"
    lstboxc.ValueMember = "ccode"
    okcl = 1

    If dtcli.Rows.Count > 0 Then
        ccode = dtcli.Rows(0)("ccode")
        Call ClientDispData1()
    End If
End Sub

Private Sub FilterClients()        

    Dim query As EnumerableRowCollection(Of DataRow) = From dataTableClients In 
    dataTableClients.AsEnumerable() Where dataTableClients.Field(Of String) 
    ("cname").Contains(txtSearch.Text.Trim()) Order By dataTableClients.Field(Of 
    String)("cname") Select dataTableClients

    Dim dataView As DataView = query.AsDataView()
    lstboxc.DataSource = dataView
    lstboxc.DisplayMember = "cname"
    lstboxc.ValueMember = "ccode"
    okcl = 1
    If dataTableClients.Rows.Count > 0 Then
        ccode = dataTableClients.Rows(0)("ccode")
        Call ClientDispData1()
    End If
End Sub

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

In Python we can use the __str__() method.

We can override it in our class like this:

class User: 

    firstName = ''
    lastName = ''
    ...

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

and when running

print(user)

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

How do I specify "not equals to" when comparing strings in an XSLT <xsl:if>?

If you want to compare to a string literal you need to put it in (single) quotes:

<xsl:if test="Count != 'N/A'">

How can I use grep to find a word inside a folder?

Don't use grep. Download Silver Searcher or ripgrep. They're both outstanding, and way faster than grep or ack with tons of options.

How to compare values which may both be null in T-SQL

Equals comparison:

((f1 IS NULL AND f2 IS NULL) OR (f1 IS NOT NULL AND f2 IS NOT NULL AND f1 = f2))

Not Equal To comparison: Just negate the Equals comparison above.

NOT ((f1 IS NULL AND f2 IS NULL) OR (f1 IS NOT NULL AND f2 IS NOT NULL AND f1 = f2))

Is it verbose? Yes, it is. However it's efficient since it doesn't call any function. The idea is to use short circuit in predicates to make sure the equal operator (=) is used only with non-null values, otherwise null would propagate up in the expression tree.

laravel foreach loop in controller

The view (blade template): Inside the loop you can retrieve whatever column you looking for

 @foreach ($products as $product)
   {{$product->sku}}
 @endforeach

Can an AJAX response set a cookie?

Also check that your server isn't setting secure cookies on a non http request. Just found out that my ajax request was getting a php session with "secure" set. Because I was not on https it was not sending back the session cookie and my session was getting reset on each ajax request.

How to get the total number of rows of a GROUP BY query?

Keep in mind that a PDOStatement is Traversable. Given a query:

$query = $dbh->query('
    SELECT
        *
    FROM
        test
');

It can be iterated over:

$it = new IteratorIterator($query);
echo '<p>', iterator_count($it), ' items</p>';

// Have to run the query again unfortunately
$query->execute();
foreach ($query as $row) {
    echo '<p>', $row['title'], '</p>';
}

Or you can do something like this:

$it = new IteratorIterator($query);
$it->rewind();

if ($it->valid()) {
    do {
        $row = $it->current();
        echo '<p>', $row['title'], '</p>';
        $it->next();
    } while ($it->valid());
} else {
    echo '<p>No results</p>';
}

Hibernate - A collection with cascade=”all-delete-orphan” was no longer referenced by the owning entity instance

Mine was completely different with Spring Boot! For me it was not due to setting collection property.

In my tests I was trying to create an entity and was getting this error for another collection that was unused!

After so much trying I just added a @Transactional on the test method and it solved it. Don't no the reason though.

How to get a float result by dividing two integer values using T-SQL?

If you came here (just like me) to find the solution for integer value, here is the answer:

CAST(9/2 AS UNSIGNED)

returns 5

How do you convert a JavaScript date to UTC?

So this is the way I had to do it because i still wanted a JavaScript date object to manipulate as a date and unfortunantly alot of these answers require you to go to a string.

//First i had a string called stringDateVar that i needed to convert to Date
var newDate = new Date(stringDateVar)

//output: 2019-01-07T04:00:00.000Z
//I needed it 2019-01-07T00:00:00.000Z because i had other logic that was dependent on that 

var correctDate = new Date(newDate.setUTCHours(0))

//This will output 2019-01-07T00:00:00.000Z on everything which allows scalability 

Python: CSV write by column rather than row

Read it in by row and then transpose it in the command line. If you're using Unix, install csvtool and follow the directions in: https://unix.stackexchange.com/a/314482/186237

Could not determine the dependencies of task ':app:crashlyticsStoreDeobsDebug' if I enable the proguard

I was facing the same issue, I resolved this by replacing dependencies in App level Build.gradle file

"""

implementation 'com.google.firebase:firebase-analytics:17.2.2'
implementation 'androidx.multidex:multidex:2.0.0'
testImplementation 'junit:junit:4.12'
implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
androidTestImplementation 'com.androidx.support.test:runner:1.1.0'
androidTestImplementation 'com.androidx.support.test.espresso:espresso-core:3.1.0'

BY

implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
implementation platform('com.google.firebase:firebase-bom:26.1.1')
implementation 'com.google.firebase:firebase-analytics'
implementation 'androidx.multidex:multidex:2.0.1'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.androidx.support.test:runner:1.1.0'
androidTestImplementation 'com.androidx.support.test.espresso:espresso-core:3.1.0'

This resolves my issue.

Error when testing on iOS simulator: Couldn't register with the bootstrap server

Well, no answers but at least one more test to make. Open Terminal and run this command: "ps-Ael | grep Z". If you get two entries, one "(clang)" and the other your app or company name, you're hosed - reboot.

If you are a developer, enter a short bug and tell Apple how absolutely annoying having to reboot is, and mention they can dup this bug to "rdar://10401934" which I just entered.

David

How do I create a transparent Activity on Android?

Add the following style in your res/values/styles.xml file (if you don’t have one, create it.) Here’s a complete file:

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <style name="Theme.Transparent" parent="android:Theme">
    <item name="android:windowIsTranslucent">true</item>
    <item name="android:windowBackground">@android:color/transparent</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowIsFloating">true</item>
    <item name="android:backgroundDimEnabled">false</item>
  </style>
</resources>

(The value @color/transparent is the color value #00000000 which I put in the res/values/color.xml file. You can also use @android:color/transparent in later Android versions.)

Then apply the style to your activity, for example:

<activity android:name=".SampleActivity" android:theme="@style/Theme.Transparent">
...
</activity>

How does HTTP_USER_AGENT work?

http://www.useragentstring.com/

Visit that page, it'll give you a good explanation of each element of your user agent.

Mozilla:

MozillaProductSlice. Claims to be a Mozilla based user agent, which is only true for Gecko browsers like Firefox and Netscape. For all other user agents it means 'Mozilla-compatible'. In modern browsers, this is only used for historical reasons. It has no real meaning anymore

Batch file to copy directories recursively

I wanted to replicate Unix/Linux's cp -r as closely as possible. I came up with the following:

xcopy /e /k /h /i srcdir destdir

Flag explanation:

/e Copies directories and subdirectories, including empty ones.
/k Copies attributes. Normal Xcopy will reset read-only attributes.
/h Copies hidden and system files also.
/i If destination does not exist and copying more than one file, assume destination is a directory.


I made the following into a batch file (cpr.bat) so that I didn't have to remember the flags:

xcopy /e /k /h /i %*

Usage: cpr srcdir destdir


You might also want to use the following flags, but I didn't:
/q Quiet. Do not display file names while copying.
/b Copies the Symbolic Link itself versus the target of the link. (requires UAC admin)
/o Copies directory and file ACLs. (requires UAC admin)

Combining multiple commits before pushing in Git

You can squash (join) commits with an Interactive Rebase. There is a pretty nice YouTube video which shows how to do this on the command line or with SmartGit:

If you are already a SmartGit user then you can select all your outgoing commits (by holding down the Ctrl key) and open the context menu (right click) to squash your commits.

It's very comfortable:

enter image description here

There is also a very nice tutorial from Atlassian which shows how it works:

What is the difference between an expression and a statement in Python?

Statements represent an action or command e.g print statements, assignment statements.

print 'hello', x = 1

Expression is a combination of variables, operations and values that yields a result value.

5 * 5 # yields 25

Lastly, expression statements

print 5*5

Meaning of ${project.basedir} in pom.xml

There are a set of available properties to all Maven projects.

From Introduction to the POM:

project.basedir: The directory that the current project resides in.

This means this points to where your Maven projects resides on your system. It corresponds to the location of the pom.xml file. If your POM is located inside /path/to/project/pom.xml then this property will evaluate to /path/to/project.

Some properties are also inherited from the Super POM, which is the case for project.build.directory. It is the value inside the <project><build><directory> element of the POM. You can get a description of all those values by looking at the Maven model. For project.build.directory, it is:

The directory where all files generated by the build are placed. The default value is target.

This is the directory that will hold every generated file by the build.

First char to upper case

public static String cap1stChar(String userIdea)
{
    char[] stringArray = userIdea.toCharArray();
    stringArray[0] = Character.toUpperCase(stringArray[0]);
    return userIdea = new String(stringArray);
}

How to stop the task scheduled in java.util.Timer class

timer.cancel();  //Terminates this timer,discarding any currently scheduled tasks.

timer.purge();   // Removes all cancelled tasks from this timer's task queue.

How can I get two form fields side-by-side, with each field’s label above the field, in CSS?

<form>
  <label for="company">
    <span>Company Name</span>
    <input type="text" id="company" />
  </label>
  <label for="contact">
    <span>Contact Name</span>
    <input type="text" id="contact" />
  </label>
</form>

label { width: 200px; float: left; margin: 0 20px 0 0; }
span { display: block; margin: 0 0 3px; font-size: 1.2em; font-weight: bold; }
input { width: 200px; border: 1px solid #000; padding: 5px; }

Illustrated at http://jsfiddle.net/H3y8j/

Get Current Session Value in JavaScript?

The session is a server side thing, you cannot access it using jQuery. You can write an Http handler (that will share the sessionid if any) and return the value from there using $.ajax.

Restoring Nuget References?

Try re-installing the packages.

In the NuGet Package Manager Console enter the following command:

Update-Package -Reinstall -ProjectName Your.Project.Name

If you want to re-install packages and restore references for the whole solution omit the -ProjectName parameter.

How to use the curl command in PowerShell?

Use splatting.

$CurlArgument = '-u', '[email protected]:yyyy',
                '-X', 'POST',
                'https://xxx.bitbucket.org/1.0/repositories/abcd/efg/pull-requests/2229/comments',
                '--data', 'content=success'
$CURLEXE = 'C:\Program Files\Git\mingw64\bin\curl.exe'
& $CURLEXE @CurlArgument

Get selected text from a drop-down list (select box) using jQuery

Try this:

$("#myselect :selected").text();

For an ASP.NET dropdown you can use the following selector:

$("[id*='MyDropDownId'] :selected")

The performance impact of using instanceof in Java

I thought it might be worth submitting a counter-example to the general consensus on this page that "instanceof" is not expensive enough to worry about. I found I had some code in an inner loop that (in some historic attempt at optimization) did

if (!(seq instanceof SingleItem)) {
  seq = seq.head();
}

where calling head() on a SingleItem returns the value unchanged. Replacing the code by

seq = seq.head();

gives me a speed-up from 269ms to 169ms, despite the fact that there are some quite heavy things happening in the loop, like string-to-double conversion. It's possible of course that the speed-up is more due to eliminating the conditional branch than to eliminating the instanceof operator itself; but I thought it worth mentioning.

Getting java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory exception

commons-logging-1.1.1.jar or jcl-over-slf4j-1.7.6.jar al

If you are using maven, use the below code.

<dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>jcl-over-slf4j</artifactId>
    <version>${slf4j.version}</version>
</dependency>

How can I get a list of all open named pipes in Windows?

The second pipe was interpreted by this web site when submitted... You need two backslashes at the beginning. So make sure to use System.IO.Directory.GetFiles(@"\\.\pipe\").

Note that I have seen this function call throw an 'illegal characters in path.' exception when one of the pipes on my machine had invalid characters. PipleList.exe worked ok though, so it seems like a bug in MS's .net code.

How to fix error with xml2-config not found when installing PHP from sources?

All you need to do instal install package libxml2-dev for example:

sudo apt-get install libxml2-dev

On CentOS/RHEL:

sudo yum install libxml2-devel

How can I get Eclipse to show .* files?

Cory is correct

@ If you're using Eclipse PDT, this is done by opening up the PHP explorer view

I just spent about half an hour looking for the little arrow, until I actually looked up what the 'PHP Explorer' view is. Here is a screenshot:

PHP perspective edit image

warning: incompatible implicit declaration of built-in function ‘xyz’

In C, using a previously undeclared function constitutes an implicit declaration of the function. In an implicit declaration, the return type is int if I recall correctly. Now, GCC has built-in definitions for some standard functions. If an implicit declaration does not match the built-in definition, you get this warning.

To fix the problem, you have to declare the functions before using them; normally you do this by including the appropriate header. I recommend not to use the -fno-builtin-* flags if possible.

Instead of stdlib.h, you should try:

#include <string.h>

That's where strcpy and strncpy are defined, at least according to the strcpy(2) man page.

The exit function is defined in stdlib.h, though, so I don't know what's going on there.

How to print a single backslash?

You should escape it with another backslash \:

print('\\')

OS X Framework Library not loaded: 'Image not found'

I ran into the same issue but the accepted solution did not work for me. Instead the solution was to modify the framework's install name.

The error in the original post is:

dyld: Library not loaded: /Library/Frameworks/TestMacFramework.framework/Versions/A/TestMacFramework
  Referenced from: /Users/samharman/Library/Developer/Xcode/DerivedData/TestMacContainer-dzabuelobzfknafuhmgooqhqrgzl/Build/Products/Debug/TestMacContainer.app/Contents/MacOS/TestMacContainer
  Reason: image not found

Note the first path after Library not loaded. The framework is being loaded from an absolute path. This path comes from the framework's install name (sometimes called rpath), which can be examined using:

otool -D MyFramework.framework/MyFramework

When a framework is embedded into an app this path should be relative and of this form: @rpath/MyFramework.framework/MyFramework. If your framework's install name is an absolute path it may not be loaded at runtime and an error similar to the one above will be produced.

The solution is to modify the install name:

install_name_tool -id "@rpath/MyFramework.framework/MyFramework" MyFramework.framework/MyFramework 

With this change I no longer get the error

How to get a date in YYYY-MM-DD format from a TSQL datetime field?

If you want to use it as a date instead of a varchar again afterwards, don't forget to convert it back:

select convert(datetime,CONVERT(char(10), GetDate(),126))

How can I do an asc and desc sort using underscore.js?

Descending order using underscore can be done by multiplying the return value by -1.

//Ascending Order:
_.sortBy([2, 3, 1], function(num){
    return num;
}); // [1, 2, 3]


//Descending Order:
_.sortBy([2, 3, 1], function(num){
    return num * -1;
}); // [3, 2, 1]

If you're sorting by strings not numbers, you can use the charCodeAt() method to get the unicode value.

//Descending Order Strings:
_.sortBy(['a', 'b', 'c'], function(s){ 
    return s.charCodeAt() * -1;
});

Regular Expressions- Match Anything

For JavaScript the best and simplest answer would seem to be /.\*/.

As suggested by others /(.*?)/ would work as well but /.\*/ is simpler. The () inside the pattern are not needed, as far as I can see nor the ending ? to match absolutely anything (including empty strings)


NON-SOLUTIONS:

  • /[\s\S]/ does NOT match empty strings so it's not the solution.

  • /[\s\S]\*/ DOES match also empty strings. But it has a problem: If you use it in your code then you can't comment out such code because the */ is interpreted as end-of-comment.

/([\s\S]\*)/ works and does not have the comment-problem. But it is longer and more complicated to understand than /.*/.

Error:Cause: unable to find valid certification path to requested target

change dependencies from compile to Implementation in build.gradle file

Java, How to add library files in netbeans?

How to import a commons-library into netbeans.

  1. Evaluate the error message in NetBeans:

    java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
    
  2. NoClassDeffFoundError means somewhere under the hood in the code you used, a method called another method which invoked a class that cannot be found. So what that means is your code did this: MyFoobarClass foobar = new MyFoobarClass() and the compiler is confused because nowhere is defined this MyFoobarClass. This is why you get an error.

  3. To know what to do next, you have to look at the error message closely. The words 'org/apache/commons' lets you know that this is the codebase that provides the tools you need. You have a choice, either you can import EVERYTHING in apache commons, or you could import JUST the LogFactory class, or you could do something in between. Like for example just get the logging bit of apache commons.

  4. You'll want to go the middle of the road and get commons-logging. Excellent choice, fire up the google and search for apache commons-logging. The first link takes you to http://commons.apache.org/proper/commons-logging/. Go to downloads. There you will find the most up-to-date ones. If your project was compiled under ancient versions of commons-logging, then use those same ancient ones because if you use the newer ones, the code may fail because the newer versions are different.

  5. You're going to want to download the commons-logging-1.1.3-bin.zip or something to that effect. Read what the name is saying. The .zip means it's a compressed file. commons-logging means that this one should contain the LogFactory class you desire. the middle 1.1.3 means that is the version. if you are compiling for an old version, you'll need to match these up, or else you risk the code not compiling right due to changes due to upgrading.

  6. Download that zip. Unzip it. Search around for things that end in .jar. In netbeans right click your project, click properties, click libraries, click "add jar/folder" and import those jars. Save the project, and re-run, and the errors should be gone.

The binaries don't include the source code, so you won't be able to drill down and see what is happening when you debug. As programmers you should be downloading "the source" of apache commons and compiling from source, generating the jars yourself and importing those for experience. You should be smart enough to understand and correct the source code you are importing. These ancient versions of apache commons might have been compiled under an older version of Java, so if you go too far back, they may not even compile unless you compile them under an ancient version of java.

How to read from a file or STDIN in Bash?

This one is easy to use on the terminal:

$ echo '1\n2\n3\n' | while read -r; do echo $REPLY; done
1
2
3

Retrieve WordPress root directory path?

For retrieving the path you can use a function <?php $path = get_home_path(); ?>. I do not want to just repeat what had been already said here, but I want to add one more thing:

If you are using windows server, which is rare case for WordPress installation, but still happens sometimes, you might face a problem with the path output. It might miss a "\" somewhere and you will get an error if you will be using such a path. So when outputting make sure to sanitize the path:

<?php 

$path = get_home_path(); 
$path = wp_normalize_path ($path);

// now $path is ready to be used :)

?>

How to fill OpenCV image with one solid color?

Create a new 640x480 image and fill it with purple (red+blue):

cv::Mat mat(480, 640, CV_8UC3, cv::Scalar(255,0,255));

Note:

  • height before width
  • type CV_8UC3 means 8-bit unsigned int, 3 channels
  • colour format is BGR

How to install packages offline?

For Pip 8.1.2 you can use pip download -r requ.txt to download packages to your local machine.

Newline in JLabel

You can use the MultilineLabel component in the Jide Open Source Components.

http://www.jidesoft.com/products/oss.htm

How to find the unclosed div tag

Div tags are easy to spot for me. Just download the file, scan it or so with netbeans, then continue debugging it. Or you can use the Google chrome developer kit, and view the page source. I'm a bit of a weird developer, I don't always use the "best" stuff. But it works for me.

I'll link you with some developer stuff I use

http://www.coffeecup.com/free-editor/

http://www.netbeans.org

Those are just a few of the good ones out there. I'm open to more suggestions to this list :D

Happy programming

-skycoder

Code for download video from Youtube on Java, Android

METHOD 1 ( Recommanded )

Library YouTubeExtractor

Add into your gradle file

 allprojects {
        repositories {
            maven { url "https://jitpack.io" }
        }
    }

And dependencies

 compile 'com.github.Commit451.YouTubeExtractor:youtubeextractor:2.1.0'

Add this small code and you done. Demo HERE

public class MainActivity extends AppCompatActivity {

    private static final String YOUTUBE_ID = "ea4-5mrpGfE";

    private final YouTubeExtractor mExtractor = YouTubeExtractor.create();


    private Callback<YouTubeExtractionResult> mExtractionCallback = new Callback<YouTubeExtractionResult>() {
        @Override
        public void onResponse(Call<YouTubeExtractionResult> call, Response<YouTubeExtractionResult> response) {
            bindVideoResult(response.body());
        }

        @Override
        public void onFailure(Call<YouTubeExtractionResult> call, Throwable t) {
            onError(t);
        }
    };


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


//        For android youtube extractor library  com.github.Commit451.YouTubeExtractor:youtubeextractor:2.1.0'
        mExtractor.extract(YOUTUBE_ID).enqueue(mExtractionCallback);

    }


    private void onError(Throwable t) {
        t.printStackTrace();
        Toast.makeText(MainActivity.this, "It failed to extract. So sad", Toast.LENGTH_SHORT).show();
    }


    private void bindVideoResult(YouTubeExtractionResult result) {

//        Here you can get download url link
        Log.d("OnSuccess", "Got a result with the best url: " + result.getBestAvailableQualityVideoUri());

        Toast.makeText(this, "result : " + result.getSd360VideoUri(), Toast.LENGTH_SHORT).show();
    }
}

You can get download link in bindVideoResult() method.

METHOD 2

Using this library android-youtubeExtractor

Add into gradle file

repositories {
    maven { url "https://jitpack.io" }
}

compile 'com.github.HaarigerHarald:android-youtubeExtractor:master-SNAPSHOT'

Here is the code for getting download url.

       String youtubeLink = "http://youtube.com/watch?v=xxxx";

    YouTubeUriExtractor ytEx = new YouTubeUriExtractor(this) {
        @Override
        public void onUrisAvailable(String videoId, String videoTitle, SparseArray<YtFile> ytFiles) {
            if (ytFiles != null) {
                int itag = 22;
// Here you can get download url
                String downloadUrl = ytFiles.get(itag).getUrl();
            }
        }
    };

    ytEx.execute(youtubeLink);

CSS text-overflow in a table cell?

It is worked for me

table {
    width: 100%;
    table-layout: fixed;
}

td {
   text-overflow: ellipsis;
   white-space: nowrap;
}

Get the device width in javascript

check it

const mq = window.matchMedia( "(min-width: 500px)" );

if (mq.matches) {
  // window width is at least 500px
} else {
  // window width is less than 500px
}

https://developer.mozilla.org/en-US/docs/Web/API/Window/matchMedia

target input by type and name (selector)

You can combine attribute selectors this way:

$("[attr1=val][attr2=val]")...

so that an element has to satisfy both conditions. Of course you can use this for more than two. Also, don't do [type=checkbox]. jQuery has a selector for that, namely :checkbox so the end result is:

$("input:checkbox[name=ProductCode]")...

Attribute selectors are slow however so the recommended approach is to use ID and class selectors where possible. You could change your markup to:

<input type="checkbox" class="ProductCode" name="ProductCode"value="396P4"> 
<input type="checkbox" class="ProductCode" name="ProductCode"value="401P4"> 
<input type="checkbox" class="ProductCode" name="ProductCode"value="F460129">

allowing you to use the much faster selector of:

$("input.ProductCode")...

How to get next/previous record in MySQL?

Using @Dan 's approach, you can create JOINs. Just use a different @variable for each sub query.

SELECT current_row.row, current_row.id, previous_row.row, previous_row.id
FROM (
  SELECT @rownum:=@rownum+1 row, a.* 
  FROM articles a, (SELECT @rownum:=0) r
  ORDER BY date, id
) as current_row
LEFT JOIN (
  SELECT @rownum2:=@rownum2+1 row, a.* 
  FROM articles a, (SELECT @rownum2:=0) r
  ORDER BY date, id
) as previous_row ON
  (current_row.id = previous_row.id) AND (current_row.row = previous_row.row - 1)

How do I determine k when using k-means clustering?

You can choose the number of clusters by visually inspecting your data points, but you will soon realize that there is a lot of ambiguity in this process for all except the simplest data sets. This is not always bad, because you are doing unsupervised learning and there's some inherent subjectivity in the labeling process. Here, having previous experience with that particular problem or something similar will help you choose the right value.

If you want some hint about the number of clusters that you should use, you can apply the Elbow method:

First of all, compute the sum of squared error (SSE) for some values of k (for example 2, 4, 6, 8, etc.). The SSE is defined as the sum of the squared distance between each member of the cluster and its centroid. Mathematically:

SSE=?Ki=1?x?cidist(x,ci)2

If you plot k against the SSE, you will see that the error decreases as k gets larger; this is because when the number of clusters increases, they should be smaller, so distortion is also smaller. The idea of the elbow method is to choose the k at which the SSE decreases abruptly. This produces an "elbow effect" in the graph, as you can see in the following picture:

enter image description here

In this case, k=6 is the value that the Elbow method has selected. Take into account that the Elbow method is an heuristic and, as such, it may or may not work well in your particular case. Sometimes, there are more than one elbow, or no elbow at all. In those situations you usually end up calculating the best k by evaluating how well k-means performs in the context of the particular clustering problem you are trying to solve.

Linux bash: Multiple variable assignment

First thing that comes into my mind:

read -r a b c <<<$(echo 1 2 3) ; echo "$a|$b|$c"

output is, unsurprisingly

1|2|3

php get values from json encode

json_decode will return the same array that was originally encoded. For instanse, if you

$array = json_decode($json, true);
echo $array['countryId'];

OR

$obj= json_decode($json);

echo $obj->countryId;

These both will echo 84. I think json_encode and json_decode function names are self-explanatory...

pip install fails with "connection error: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:598)"

I tried majority of the solutions provided in this answer blog, however none of them worked, I had this ssl certificant error as I try to install python packages.

I succeed by following command:

python -m pip install PACKAGENAME --trusted-host=pypi.python.org --trusted-host=pypi.org --trusted-host=files.pythonhosted.org 

Cannot delete or update a parent row: a foreign key constraint fails

You could create a trigger to delete the referenced rows in before deleting the job.

    DELIMITER $$
    CREATE TRIGGER before_jobs_delete 
        BEFORE DELETE ON jobs
        FOR EACH ROW 
    BEGIN
        delete from advertisers where advertiser_id=OLD.advertiser_id;
    END$$
    DELIMITER ;

Java regex to extract text between tags

You're on the right track. Now you just need to extract the desired group, as follows:

final Pattern pattern = Pattern.compile("<tag>(.+?)</tag>", Pattern.DOTALL);
final Matcher matcher = pattern.matcher("<tag>String I want to extract</tag>");
matcher.find();
System.out.println(matcher.group(1)); // Prints String I want to extract

If you want to extract multiple hits, try this:

public static void main(String[] args) {
    final String str = "<tag>apple</tag><b>hello</b><tag>orange</tag><tag>pear</tag>";
    System.out.println(Arrays.toString(getTagValues(str).toArray())); // Prints [apple, orange, pear]
}

private static final Pattern TAG_REGEX = Pattern.compile("<tag>(.+?)</tag>", Pattern.DOTALL);

private static List<String> getTagValues(final String str) {
    final List<String> tagValues = new ArrayList<String>();
    final Matcher matcher = TAG_REGEX.matcher(str);
    while (matcher.find()) {
        tagValues.add(matcher.group(1));
    }
    return tagValues;
}

However, I agree that regular expressions are not the best answer here. I'd use XPath to find elements I'm interested in. See The Java XPath API for more info.

Programmatically relaunch/recreate an activity?

Combining some answers here you can use something like the following.

class BaseActivity extends SherlockFragmentActivity
{
    // Backwards compatible recreate().
    @Override
    public void recreate()
    {
        if (android.os.Build.VERSION.SDK_INT >= 11)
        {
            super.recreate();
        }
        else
        {
            startActivity(getIntent());
            finish();
        }
    }
}

Testing

I tested it a bit, and there are some problems:

  1. If the activity is the lowest one on the stack, calling startActivity(...); finish(); just exist the app and doesn't restart the activity.
  2. super.recreate() doesn't actually act the same way as totally recreating the activity. It is equivalent to rotating the device so if you have any Fragments with setRetainInstance(true) they won't be recreated; merely paused and resumed.

So currently I don't believe there is an acceptable solution.

How to delete an app from iTunesConnect / App Store Connect

Apps can’t be deleted if they are part of a Game Center group, in an app bundle, or currently displayed on a store. You’ll want to remove the app from sale or from the group if you want to delete it.

Source: iTunes Connect Developer Guide - Transferring and Deleting Apps

Run / Open VSCode from Mac Terminal

Somehow using Raja's approach worked for me only once, after a reboot, it seems gone. To make it persistent across Mac OS reboot, I added this line into my ~/.zshrc since I'm using zsh:

export PATH=/Applications/Visual\ Studio\ Code.app/Contents/Resources/app/bin:$PATH then

source ~/.zshrc now, I could just do

code .

even after I reboot my Mac.

SASS - use variables across multiple files

You can do it like this:

I have a folder named utilities and inside that I have a file named _variables.scss

in that file i declare variables like so:

$black: #000;
$white: #fff;

then I have the style.scss file in which i import all of my other scss files like this:

// Utilities
@import "utilities/variables";

// Base Rules
@import "base/normalize";
@import "base/global";

then, within any of the files I have imported, I should be able to access the variables I have declared.

Just make sure you import the variable file before any of the others you would like to use it in.

Hide particular div onload and then show div after click

This is an easier way to do it. Hope this helps...

<script type="text/javascript">
$(document).ready(function () {
    $("#preview").toggle(function() {
        $("#div1").hide();
        $("#div2").show();
    }, function() {
        $("#div1").show();
        $("#div2").hide();
    });
});

<div id="div1">
This is preview Div1. This is preview Div1.
</div>

<div id="div2" style="display:none;">
This is preview Div2 to show after div 1 hides.
</div>

<div id="preview" style="color:#999999; font-size:14px">
PREVIEW
</div>
  • If you want the div to be hidden on load, make the style display:none
  • Use toggle rather than click function.


Links:

JQuery Tutorials

JQuery References

Intellij idea cannot resolve anything in maven

For me to sort this issue I had to go to Build, Execution, Deployment -> Build Tools -> Maven -> Importing and set JDK for import to JAVA_HOME! Then Reload all maven projects from the maven settings. All imports now work!!

How do I set the eclipse.ini -vm option?

You have to edit the eclipse.ini file to have an entry similar to this:

C:\Java\JDK\1.5\bin\javaw.exe (your location of java executable)
-vmargs
-Xms64m   (based on you memory requirements)
-Xmx1028m

Also remember that in eclipse.ini, anything meant for Eclipse should be before the -vmargs line and anything for JVM should be after the -vmargs line.

How do I force make/GCC to show me the commands?

Build system independent method

make SHELL='sh -x'

is another option. Sample Makefile:

a:
    @echo a

Output:

+ echo a
a

This sets the special SHELL variable for make, and -x tells sh to print the expanded line before executing it.

One advantage over -n is that is actually runs the commands. I have found that for some projects (e.g. Linux kernel) that -n may stop running much earlier than usual probably because of dependency problems.

One downside of this method is that you have to ensure that the shell that will be used is sh, which is the default one used by Make as they are POSIX, but could be changed with the SHELL make variable.

Doing sh -v would be cool as well, but Dash 0.5.7 (Ubuntu 14.04 sh) ignores for -c commands (which seems to be how make uses it) so it doesn't do anything.

make -p will also interest you, which prints the values of set variables.

CMake generated Makefiles always support VERBOSE=1

As in:

mkdir build
cd build
cmake ..
make VERBOSE=1

Dedicated question at: Using CMake with GNU Make: How can I see the exact commands?

Max tcp/ip connections on Windows Server 2008

How many thousands of users?

I've run some TCP/IP client/server connection tests in the past on Windows 2003 Server and managed more than 70,000 connections on a reasonably low spec VM. (see here for details: http://www.lenholgate.com/blog/2005/10/the-64000-connection-question.html). I would be extremely surprised if Windows 2008 Server is limited to less than 2003 Server and, IMHO, the posting that Cloud links to is too vague to be much use. This kind of question comes up a lot, I blogged about why I don't really think that it's something that you should actually worry about here: http://www.serverframework.com/asynchronousevents/2010/12/one-million-tcp-connections.html.

Personally I'd test it and see. Even if there is no inherent limit in the Windows 2008 Server version that you intend to use there will still be practical limits based on memory, processor speed and server design.

If you want to run some 'generic' tests you can use my multi-client connection test and the associated echo server. Detailed here: http://www.lenholgate.com/blog/2005/11/windows-tcpip-server-performance.html and here: http://www.lenholgate.com/blog/2005/11/simple-echo-servers.html. These are what I used to run my own tests for my server framework and these are what allowed me to create 70,000 active connections on a Windows 2003 Server VM with 760MB of memory.

Edited to add details from the comment below...

If you're already thinking of multiple servers I'd take the following approach.

  1. Use the free tools that I link to and prove to yourself that you can create a reasonable number of connections onto your target OS (beware of the Windows limits on dynamic ports which may cause your client connections to fail, search for MAX_USER_PORT).

  2. during development regularly test your actual server with test clients that can create connections and actually 'do something' on the server. This will help to prevent you building the server in ways that restrict its scalability. See here: http://www.serverframework.com/asynchronousevents/2010/10/how-to-support-10000-or-more-concurrent-tcp-connections-part-2-perf-tests-from-day-0.html

Getting all files in directory with ajax

Javascript which runs on the client machine can't access the local disk file system due to security restrictions.

If you want to access the client's disk file system then look into an embedded client application which you serve up from your webpage, like an Applet, Silverlight or something like that. If you like to access the server's disk file system, then look for the solution in the server side corner using a server side programming language like Java, PHP, etc, whatever your webserver is currently using/supporting.

How can I install a CPAN module into a local directory?

local::lib will help you. It will convince "make install" (and "Build install") to install to a directory you can write to, and it will tell perl how to get at those modules.

In general, if you want to use a module that is in a blib/ directory, you want to say perl -Mblib ... where ... is how you would normally invoke your script.

Why do we usually use || over |? What is the difference?

| is a bitwise operator. || is a logical operator.

One will take two bits and or them.

One will determine truth (this OR that) If this is true or that is true, then the answer is true.

Oh, and dang people answer these questions fast.

How can I declare dynamic String array in Java

no, there is no way to make array length dynamic in java. you can use ArrayList or other List implementations instead.

Best way to check if a drop down list contains a value?

You could try checking to see if this method returns a null:

if (ddlCustomerNumber.Items.FindByText(GetCustomerNumberCookie().ToString()) != null)
    ddlCustomerNumber.SelectedIndex = 0;

Elasticsearch difference between MUST and SHOULD bool query

must means: The clause (query) must appear in matching documents. These clauses must match, like logical AND.

should means: At least one of these clauses must match, like logical OR.

Basically they are used like logical operators AND and OR. See this.

Now in a bool query:

must means: Clauses that must match for the document to be included.

should means: If these clauses match, they increase the _score; otherwise, they have no effect. They are simply used to refine the relevance score for each document.


Yes you can use multiple filters inside must.

Given a DateTime object, how do I get an ISO 8601 date in string format?

DateTime.UtcNow.ToString("s")

Returns something like 2008-04-10T06:30:00

UtcNow obviously returns a UTC time so there is no harm in:

string.Concat(DateTime.UtcNow.ToString("s"), "Z")

Java - Including variables within strings?

Since Java 15, you can use a non-static string method called String::formatted(Object... args)

Example:

String foo = "foo";
String bar = "bar";

String str = "First %s, then %s".formatted(foo, bar);     

Output:

"First foo, then bar"

How to send json data in POST request using C#

You can use either HttpClient or RestSharp. Since I do not know what your code is, here is an example using HttpClient:

using (var client = new HttpClient())
{
    // This would be the like http://www.uber.com
    client.BaseAddress = new Uri("Base Address/URL Address");

    // serialize your json using newtonsoft json serializer then add it to the StringContent
    var content = new StringContent(YourJson, Encoding.UTF8, "application/json") 

    // method address would be like api/callUber:SomePort for example
    var result = await client.PostAsync("Method Address", content);
    string resultContent = await result.Content.ReadAsStringAsync();   
}

Reducing MongoDB database file size

If you need to run a full repair, use the repairpath option. Point it to a disk with more available space.

For example, on my Mac I've used:

mongod --config /usr/local/etc/mongod.conf --repair --repairpath /Volumes/X/mongo_repair

Update: Per MongoDB Core Server Ticket 4266, you may need to add --nojournal to avoid an error:

mongod --config /usr/local/etc/mongod.conf --repair --repairpath /Volumes/X/mongo_repair --nojournal

How to decorate a class?

Here is an example which answers the question of returning the parameters of a class. Moreover, it still respects the chain of inheritance, i.e. only the parameters of the class itself are returned. The function get_params is added as a simple example, but other functionalities can be added thanks to the inspect module.

import inspect 

class Parent:
    @classmethod
    def get_params(my_class):
        return list(inspect.signature(my_class).parameters.keys())

class OtherParent:
    def __init__(self, a, b, c):
        pass

class Child(Parent, OtherParent):
    def __init__(self, x, y, z):
        pass

print(Child.get_params())
>>['x', 'y', 'z']

how to create a window with two buttons that will open a new window

You add your ActionListener twice to button. So correct your code for button2 to

  JButton button2 = new JButton("hello agin2");
  panel.add(button2);
  button2.addActionListener (new Action2());//note the button2 here instead of button

Furthermore, perform your Swing operations on the correct thread by using EventQueue.invokeLater

Why do I always get the same sequence of random numbers with rand()?

You have to seed it. Seeding it with the time is a good idea:

srand()

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

int main ()
{
  srand ( time(NULL) );
  printf ("Random Number: %d\n", rand() %100);
  return 0;
}

You get the same sequence because rand() is automatically seeded with the a value of 1 if you do not call srand().

Edit

Due to comments

rand() will return a number between 0 and RAND_MAX (defined in the standard library). Using the modulo operator (%) gives the remainder of the division rand() / 100. This will force the random number to be within the range 0-99. For example, to get a random number in the range of 0-999 we would apply rand() % 1000.

Remove property for all objects in array

i have tried with craeting a new object without deleting the coulmns in Vue.js.

let data =this.selectedContactsDto[];

//selectedContactsDto[] = object with list of array objects created in my project

console.log(data); let newDataObj= data.map(({groupsList,customFields,firstname, ...item }) => item); console.log("newDataObj",newDataObj);

Using setattr() in python

Suppose you want to give attributes to an instance which was previously not written in code. The setattr() does just that. It takes the instance of the class self and key and value to set.

class Example:
    def __init__(self, **kwargs):
        for key, value in kwargs.items():
            setattr(self, key, value)

Registering for Push Notifications in Xcode 8/Swift 3.0?

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

    if #available(iOS 10, *) {

        //Notifications get posted to the function (delegate):  func userNotificationCenter(_ center: UNUserNotificationCenter, didReceive response: UNNotificationResponse, withCompletionHandler completionHandler: () -> Void)"


        UNUserNotificationCenter.current().requestAuthorization(options: [.alert, .badge, .sound]) { (granted, error) in

            guard error == nil else {
                //Display Error.. Handle Error.. etc..
                return
            }

            if granted {
                //Do stuff here..

                //Register for RemoteNotifications. Your Remote Notifications can display alerts now :)
                DispatchQueue.main.async {
                    application.registerForRemoteNotifications()
                }
            }
            else {
                //Handle user denying permissions..
            }
        }

        //Register for remote notifications.. If permission above is NOT granted, all notifications are delivered silently to AppDelegate.
        application.registerForRemoteNotifications()
    }
    else {
        let settings = UIUserNotificationSettings(types: [.alert, .badge, .sound], categories: nil)
        application.registerUserNotificationSettings(settings)
        application.registerForRemoteNotifications()
    }

    return true
}

How to draw vectors (physical 2D/3D vectors) in MATLAB?

I found this arrow(start, end) function on MATLAB Central which is perfect for this purpose of drawing vectors with true magnitude and direction.

How to select only date from a DATETIME field in MySQL?

Yo can try this:

SELECT CURDATE();

If you check the following:

SELECT NOW(); SELECT DATE(NOW()); SELECT DATE_FORMAT(NOW(),'%Y-%m-%d');

You can see that it takes a long time.

git status shows modifications, git checkout -- <file> doesn't remove them

Nothing else on this page worked. This finally worked for me. Showing no untracked, or commited files.

git add -A
git reset --hard

Adding default parameter value with type hint in Python

If you're using typing (introduced in Python 3.5) you can use typing.Optional, where Optional[X] is equivalent to Union[X, None]. It is used to signal that the explicit value of None is allowed . From typing.Optional:

def foo(arg: Optional[int] = None) -> None:
    ...

Convert form data to JavaScript object with jQuery

This function should handle multidimensional arrays along with multiple elements with the same name.

I've been using it for a couple years so far:

jQuery.fn.serializeJSON=function() {
  var json = {};
  jQuery.map(jQuery(this).serializeArray(), function(n, i) {
    var _ = n.name.indexOf('[');
    if (_ > -1) {
      var o = json;
      _name = n.name.replace(/\]/gi, '').split('[');
      for (var i=0, len=_name.length; i<len; i++) {
        if (i == len-1) {
          if (o[_name[i]]) {
            if (typeof o[_name[i]] == 'string') {
              o[_name[i]] = [o[_name[i]]];
            }
            o[_name[i]].push(n.value);
          }
          else o[_name[i]] = n.value || '';
        }
        else o = o[_name[i]] = o[_name[i]] || {};
      }
    }
    else {
      if (json[n.name] !== undefined) {
        if (!json[n.name].push) {
          json[n.name] = [json[n.name]];
        }
        json[n.name].push(n.value || '');
      }
      else json[n.name] = n.value || '';      
    }
  });
  return json;
};

How to return a complex JSON response with Node.js?

[Edit] After reviewing the Mongoose documentation, it looks like you can send each query result as a separate chunk; the web server uses chunked transfer encoding by default so all you have to do is wrap an array around the items to make it a valid JSON object.

Roughly (untested):

app.get('/users/:email/messages/unread', function(req, res, next) {
  var firstItem=true, query=MessageInfo.find(/*...*/);
  res.writeHead(200, {'Content-Type': 'application/json'});
  query.each(function(docs) {
    // Start the JSON array or separate the next element.
    res.write(firstItem ? (firstItem=false,'[') : ',');
    res.write(JSON.stringify({ msgId: msg.fileName }));
  });
  res.end(']'); // End the JSON array and response.
});

Alternatively, as you mention, you can simply send the array contents as-is. In this case the response body will be buffered and sent immediately, which may consume a large amount of additional memory (above what is required to store the results themselves) for large result sets. For example:

// ...
var query = MessageInfo.find(/*...*/);
res.writeHead(200, {'Content-Type': 'application/json'});
res.end(JSON.stringify(query.map(function(x){ return x.fileName })));

python multithreading wait till all threads finished

You need to use join method of Thread object in the end of the script.

t1 = Thread(target=call_script, args=(scriptA + argumentsA))
t2 = Thread(target=call_script, args=(scriptA + argumentsB))
t3 = Thread(target=call_script, args=(scriptA + argumentsC))

t1.start()
t2.start()
t3.start()

t1.join()
t2.join()
t3.join()

Thus the main thread will wait till t1, t2 and t3 finish execution.

Conda activate not working?

The anaconda functions are not exported by default, it can be done by using the following command:

$ source ~/anaconda3/etc/profile.d/conda.sh $ conda activate my_env

Cannot read property 'push' of undefined when combining arrays

order[] is undefined that's why

Just define order[1]...[n] to = some value

this should fix it

How to disable Google Chrome auto update?

Disable Chrome Version Auto Update - All-in-One Solution

With some of the answers here for disabling Google Chrome automatic updates, I've come up with a solution that uses specific group policy settings and also a PowerShell startup script to rename the GoogleUpdate.exe, disable the correlated services, and disable the correlated Task Scheduler tasks.

I'm posting as an answer in case someone else needs an all-in-one solution that can easily be expanded on (or toned down some) if needed and potentially save them some time.

PowerShell (Startup Script)

## -- Rename the Google Update executable file
$Chrome = "${env:ProgramFiles(x86)}\Google\Update\GoogleUpdate.exe";
If(Test-Path($Chrome)){Rename-Item -Path $Chrome -NewName "Old_GoogleUpdate.exe.old" -Force};

$Chrome = "$env:ProgramFiles\Google\Update\GoogleUpdate.exe";
If(Test-Path($Chrome)){Rename-Item -Path $Chrome -NewName "Old_GoogleUpdate.exe.old" -Force};

## -- Stop and disable the Google Update services that run to update Chrome
$GUpdateServices = (Get-Service | ?{$_.DisplayName -match "Google Update Service"}).Name;
$GUpdateServices | % {
    $status = (Get-Service -Name $_).Status;
    If($status -ne "Stopped"){Stop-Service $_ -Force};
    $sType  = (Get-Service -Name $_).StartType;
    If($sType -ne "Disabled"){Set-Service $_ -StartupType Disabled};
    };

## -- Disable Chrome Update Scheduled Tasks
$GUdateTasks = (Get-ScheduledTask -TaskPath "\" -TaskName "*GoogleUpdateTask*");
$GUdateTasks | % {If($_.State -ne "Disabled"){Disable-ScheduledTask -TaskName $_.TaskName}};

Group Policy Settings (Computer Configuration)

Be sure the Software Restriction policy blocks EXE file types at a minimum for these specific folder locations but the defaults should work fine if you leave as-is.

enter image description here


Additional Resources

HTML if image is not found

its works for me that if you dont want to use alt attribute if image break then you can use this piece of code and set accordingly.

<h1>
  <a> 
   <object data="~/img/Logo.jpg" type="image/png">
     Your Custom Text Here
   </object>
  </a>
</h1>

ImportError: No module named Crypto.Cipher

Try with pip3:

sudo pip3 install pycrypto

SQL time difference between two dates result in hh:mm:ss

It's A Script Write Copy then write in your script file and change your requered field and get out put

DECLARE @Sdate DATETIME, @Edate DATETIME, @Timediff VARCHAR(100)
SELECT @Sdate = '02/12/2014 08:40:18.000',@Edate='02/13/2014 09:52:48.000'
SET @Timediff=DATEDIFF(s, @Sdate, @Edate)
SELECT CONVERT(VARCHAR(5),@Timediff/3600)+':'+convert(varchar(5),@Timediff%3600/60)+':'+convert(varchar(5),@Timediff%60) AS TimeDiff

Use dynamic variable names in `dplyr`

Here's another version, and it's arguably a bit simpler.

multipetal <- function(df, n) {
    varname <- paste("petal", n, sep=".")
    df<-mutate_(df, .dots=setNames(paste0("Petal.Width*",n), varname))
    df
}

for(i in 2:5) {
    iris <- multipetal(df=iris, n=i)
}

> head(iris)
Sepal.Length Sepal.Width Petal.Length Petal.Width Species petal.2 petal.3 petal.4 petal.5
1          5.1         3.5          1.4         0.2  setosa     0.4     0.6     0.8       1
2          4.9         3.0          1.4         0.2  setosa     0.4     0.6     0.8       1
3          4.7         3.2          1.3         0.2  setosa     0.4     0.6     0.8       1
4          4.6         3.1          1.5         0.2  setosa     0.4     0.6     0.8       1
5          5.0         3.6          1.4         0.2  setosa     0.4     0.6     0.8       1
6          5.4         3.9          1.7         0.4  setosa     0.8     1.2     1.6       2

Node.js: Difference between req.query[] and req.params

req.params contains route parameters (in the path portion of the URL), and req.query contains the URL query parameters (after the ? in the URL).

You can also use req.param(name) to look up a parameter in both places (as well as req.body), but this method is now deprecated.

MSOnline can't be imported on PowerShell (Connect-MsolService error)

The following is needed:

  • MS Online Services Assistant needs to be downloaded and installed.
  • MS Online Module for PowerShell needs to be downloaded and installed
  • Connect to Microsoft Online in PowerShell

Source: http://www.msdigest.net/2012/03/how-to-connect-to-office-365-with-powershell/

Then Follow this one if you're running a 64bits computer: I’m running a x64 OS currently (Win8 Pro).

Copy the folder MSOnline from (1) –> (2) as seen here

1) C:\Windows\System32\WindowsPowerShell\v1.0\Modules(MSOnline)

2) C:\Windows\SysWOW64\WindowsPowerShell\v1.0\Modules(MSOnline)

Source: http://blog.clauskonrad.net/2013/06/powershell-and-c-cant-load-msonline.html

Hope this is better and can save some people's time

Access multiple viewchildren using @viewchild

Use the @ViewChildren decorator combined with QueryList. Both of these are from "@angular/core"

@ViewChildren(CustomComponent) customComponentChildren: QueryList<CustomComponent>;

Doing something with each child looks like: this.customComponentChildren.forEach((child) => { child.stuff = 'y' })

There is further documentation to be had at angular.io, specifically: https://angular.io/docs/ts/latest/cookbook/component-communication.html#!#sts=Parent%20calls%20a%20ViewChild

How to clear exisiting dropdownlist items when its content changes?

Just 2 simple steps to solve your issue

First of all check AppendDataBoundItems property and make it assign false

Secondly clear all the items using property .clear()

{
ddl1.Items.Clear();
ddl1.datasource = sql1;
ddl1.DataBind();
}

Getting started with Haskell

The first answer is a very good one. In order to get to the Expert level, you should do a PhD with some of the Experts themselves.

I suggest you to visit the Haskell page: http://haskell.org. There you have a lot of material, and a lot of references to the most up-to-date stuff in Haskell, approved by the Haskell community.

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

Generally

static: no need to create object we can directly call using

ClassName.methodname()

Non Static: we need to create a object like

ClassName obj=new ClassName()
obj.methodname();

Remove duplicates from an array of objects in JavaScript

Another way would be to use reduce function and have a new array to be the accumulator. If there is already a thing with the same name in the accumulator array then don't add it there.

let list = things.thing;
list = list.reduce((accumulator, thing) => {
    if (!accumulator.filter((duplicate) => thing.name === duplicate.name)[0]) {
        accumulator.push(thing);
    }
    return accumulator;
}, []);
thing.things = list;

I'm adding this answer, because I couldn't find nice, readable es6 solution (I use babel to handle arrow functions) that's compatible with Internet Explorer 11. The problem is IE11 doesn't have Map.values() or Set.values() without polyfill. For the same reason I used filter()[0] to get first element instead of find().

Python Matplotlib Y-Axis ticks on Right Side of Plot

joaquin's answer works, but has the side effect of removing ticks from the left side of the axes. To fix this, follow up tick_right() with a call to set_ticks_position('both'). A revised example:

from matplotlib import pyplot as plt

f = plt.figure()
ax = f.add_subplot(111)
ax.yaxis.tick_right()
ax.yaxis.set_ticks_position('both')
plt.plot([2,3,4,5])
plt.show()

The result is a plot with ticks on both sides, but tick labels on the right.

enter image description here

Moving up one directory in Python

Obviously that os.chdir('..') is the right answer here. But just FYI, if in the future you come across situation when you have to extensively manipulate directories and paths, here is a great package (Unipath) which lets you treat them as Python objects: https://pypi.python.org/pypi/Unipath

so that you could do something like this:

>>> from unipath import Path
>>> p = Path("/usr/lib/python2.5/gopherlib.py")
>>> p.parent
Path("/usr/lib/python2.5")
>>> p.name
Path("gopherlib.py")
>>> p.ext
'.py'

Discard all and get clean copy of latest revision?

Those steps should be able to be shortened down to:

hg pull
hg update -r MY_BRANCH -C

The -C flag tells the update command to discard all local changes before updating.

However, this might still leave untracked files in your repository. It sounds like you want to get rid of those as well, so I would use the purge extension for that:

hg pull
hg update -r MY_BRANCH -C
hg purge

In any case, there is no single one command you can ask Mercurial to perform that will do everything you want here, except if you change the process to that "full clone" method that you say you can't do.

How to use \n new line in VB msgbox() ...?

msgbox "This is the first line" & vbcrlf & "and this is the second line"

or in .NET msgbox "This is the first line" & Environment.NewLine & "and this is the second line"

How to change xampp localhost to another folder ( outside xampp folder)?

It can be done in two steps for Ubuntu 14.04 with Xampp 1.8.3-5

Step 1:- Change DocumentRoot and Directory path in /opt/lampp/etc/httpd.conf from

DocumentRoot "/opt/lampp/htdocs" and Directory "/opt/lampp/htdocs"

to DocumentRoot "/home/user/Desktop/js" and Directory "/home/user/Desktop/js"

Step 2:- Change the rights of folder (in path and its parent folders to 777) eg via

sudo chmod -R 777 /home/user/Desktop/js

How to check Network port access and display useful message?

Actually Shay levy's answer is almost correct but i got an weird issue as i mentioned in his comment column. So i split the command into two lines and it works fine.

$Ipaddress= Read-Host "Enter the IP address:"
$Port= Read-host "Enter the port number to access:"

$t = New-Object Net.Sockets.TcpClient
$t.Connect($Ipaddress,$Port)
    if($t.Connected)
    {
        "Port $Port is operational"
    }
    else
    {
        "Port $Port is closed, You may need to contact your IT team to open it. "
    }

Cannot call getSupportFragmentManager() from activity

get current activity from parent, then using this code

getActivity().getSupportFragmentManager()

How to compile without warnings being treated as errors?

-Wall and -Werror compiler options can cause it, please check if those are used in compiler settings.

No found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations:

When you use @DataJpaTest you need to load classes using @Import explicitly. It wouldn't load you for auto.

How do I link to Google Maps with a particular longitude and latitude?

If you want to open Google Maps in a browser:

http://maps.google.com/?q=<lat>,<lng>

To open the Google Maps app on an iOS mobile device, use the Google Maps URL Scheme:

comgooglemaps://?q=<lat>,<lng>

To open the Google Maps app on Android, use the geo: intent:

geo:<lat>,<lng>?z=<zoom>

intellij incorrectly saying no beans of type found for autowired repository

It can be solved by placing @EnableAutoConfiguration on spring boot application main class.

Integrating CSS star rating into an HTML form

Here is how to integrate CSS star rating into an HTML form without using javascript (only html and css):

CSS:

.txt-center {
    text-align: center;
}
.hide {
    display: none;
}

.clear {
    float: none;
    clear: both;
}

.rating {
    width: 90px;
    unicode-bidi: bidi-override;
    direction: rtl;
    text-align: center;
    position: relative;
}

.rating > label {
    float: right;
    display: inline;
    padding: 0;
    margin: 0;
    position: relative;
    width: 1.1em;
    cursor: pointer;
    color: #000;
}

.rating > label:hover,
.rating > label:hover ~ label,
.rating > input.radio-btn:checked ~ label {
    color: transparent;
}

.rating > label:hover:before,
.rating > label:hover ~ label:before,
.rating > input.radio-btn:checked ~ label:before,
.rating > input.radio-btn:checked ~ label:before {
    content: "\2605";
    position: absolute;
    left: 0;
    color: #FFD700;
}

HTML:

<div class="txt-center">
    <form>
        <div class="rating">
            <input id="star5" name="star" type="radio" value="5" class="radio-btn hide" />
            <label for="star5">?</label>
            <input id="star4" name="star" type="radio" value="4" class="radio-btn hide" />
            <label for="star4">?</label>
            <input id="star3" name="star" type="radio" value="3" class="radio-btn hide" />
            <label for="star3">?</label>
            <input id="star2" name="star" type="radio" value="2" class="radio-btn hide" />
            <label for="star2">?</label>
            <input id="star1" name="star" type="radio" value="1" class="radio-btn hide" />
            <label for="star1">?</label>
            <div class="clear"></div>
        </div>
    </form>
</div>

Please check the demo

Passing arguments to "make run"

This question is almost three years old, but anyway...

If you're using GNU make, this is easy to do. The only problem is that make will interpret non-option arguments in the command line as targets. The solution is to turn them into do-nothing targets, so make won't complain:

# If the first argument is "run"...
ifeq (run,$(firstword $(MAKECMDGOALS)))
  # use the rest as arguments for "run"
  RUN_ARGS := $(wordlist 2,$(words $(MAKECMDGOALS)),$(MAKECMDGOALS))
  # ...and turn them into do-nothing targets
  $(eval $(RUN_ARGS):;@:)
endif

prog: # ...
    # ...

.PHONY: run
run : prog
    @echo prog $(RUN_ARGS)

Running this gives:

$ make run foo bar baz
prog foo bar baz

iframe refuses to display

For any of you calling back to the same server for your IFRAME, pass this simple header inside the IFRAME page:

Content-Security-Policy: frame-ancestors 'self'

Or, add this to your web server's CSP configuration.

Is there a command for formatting HTML in the Atom editor?

  1. Go to "Packages" in atom editor.
  2. Then in "Packages" view choose "Settings View".
  3. Choose "Install Packages/Themes".
  4. Search for "Atom Beautify" and install it.

List of lists into numpy array

>>> numpy.array([[1, 2], [3, 4]]) 
array([[1, 2], [3, 4]])

Cropping images in the browser BEFORE the upload

#change-avatar-file is a file input #change-avatar-file is a img tag (the target of jcrop) The "key" is FR.onloadend Event https://developer.mozilla.org/en-US/docs/Web/API/FileReader

$('#change-avatar-file').change(function(){
        var currentImg;
        if ( this.files && this.files[0] ) {
            var FR= new FileReader();
            FR.onload = function(e) {
                $('#avatar-change-img').attr( "src", e.target.result );
                currentImg = e.target.result;
            };
            FR.readAsDataURL( this.files[0] );
            FR.onloadend = function(e){
                //console.log( $('#avatar-change-img').attr( "src"));
                var jcrop_api;

                $('#avatar-change-img').Jcrop({
                    bgFade:     true,
                    bgOpacity: .2,
                    setSelect: [ 60, 70, 540, 330 ]
                },function(){
                    jcrop_api = this;
                });
            }
        }
    });

How to redirect to previous page in Ruby On Rails?

In your edit action, store the requesting url in the session hash, which is available across multiple requests:

session[:return_to] ||= request.referer

Then redirect to it in your update action, after a successful save:

redirect_to session.delete(:return_to)

How to transfer paid android apps from one google account to another google account

You will not be able to do that. You can download apps again to the same userid account on different devices, but you cannot transfer those licenses to other userids.

There is no way to do this programatically - I don't think you can do that practically (except for trying to call customer support at the Play Store).

When to use pthread_exit() and when to use pthread_join() in Linux?

As explained in the openpub documentations,

pthread_exit() will exit the thread that calls it.

In your case since the main calls it, main thread will terminate whereas your spawned threads will continue to execute. This is mostly used in cases where the main thread is only required to spawn threads and leave the threads to do their job

pthread_join will suspend execution of the thread that has called it unless the target thread terminates

This is useful in cases when you want to wait for thread/s to terminate before further processing in main thread.

Iterating on a file doesn't work the second time

Of course. That is normal and sane behaviour. Instead of closing and re-opening, you could rewind the file.

Casting LinkedHashMap to Complex Object

You can use ObjectMapper.convertValue(), either value by value or even for the whole list. But you need to know the type to convert to:

POJO pojo = mapper.convertValue(singleObject, POJO.class);
// or:
List<POJO> pojos = mapper.convertValue(listOfObjects, new TypeReference<List<POJO>>() { });

this is functionally same as if you did:

byte[] json = mapper.writeValueAsBytes(singleObject);
POJO pojo = mapper.readValue(json, POJO.class);

but avoids actual serialization of data as JSON, instead using an in-memory event sequence as the intermediate step.

Under which circumstances textAlign property works in Flutter?

Specify crossAxisAlignment: CrossAxisAlignment.start in your column

Why am I getting a NoClassDefFoundError in Java?

The technique below helped me many times:

System.out.println(TheNoDefFoundClass.class.getProtectionDomain().getCodeSource().getLocation());

where the TheNoDefFoundClass is the class that might be "lost" due to a preference for an older version of the same library used by your program. This most frequently happens with the cases, when the client software is being deployed into a dominant container, armed with its own classloaders and tons of ancient versions of most popular libs.

shell script. how to extract string using regular expressions

One way would be with sed. For example:

echo $name | sed -e 's?http://www\.??'

Normally the sed regular expressions are delimited by `/', but you can use '?' since you're searching for '/'. Here's another bash trick. @DigitalTrauma's answer reminded me that I ought to suggest it. It's similar:

echo ${name#http://www.}

(DigitalTrauma also gets credit for reminding me that the "http://" needs to be handled.)

How to Add Stacktrace or debug Option when Building Android Studio Project

To Increase Maximum heap: Click to open your Android Studio, look at below pictures. Step by step. ANDROID STUDIO v2.1.2

Click to navigate to Settings from the Configure or GO TO FILE SETTINGS at the top of Android Studio.

enter image description here

check also the android compilers from the link to confirm if it also change if not increase to the same size you modify from the compiler link.

Note: You can increase the size base on your memory capacity and remember this setting is base on Android Studio v2.1.2

Difference between Hashing a Password and Encrypting it

Hashing algorithms are usually cryptographic in nature, but the principal difference is that encryption is reversible through decryption, and hashing is not.

An encryption function typically takes input and produces encrypted output that is the same, or slightly larger size.

A hashing function takes input and produces a typically smaller output, typically of a fixed size as well.

While it isn't possible to take a hashed result and "dehash" it to get back the original input, you can typically brute-force your way to something that produces the same hash.

In other words, if a authentication scheme takes a password, hashes it, and compares it to a hashed version of the requires password, it might not be required that you actually know the original password, only its hash, and you can brute-force your way to something that will match, even if it's a different password.

Hashing functions are typically created to minimize the chance of collisions and make it hard to just calculate something that will produce the same hash as something else.

ES6 export all values from object

Every answer requires changing of the import statements.

If you want to be able to use:

import {a} from './my-module'           // a === 1
import * as myModule from './my-module' // myModule.a === 1

as in the question, and in your my-module you have everything that you need to export in one object (which can be useful e.g. if you want to validate the exported values with Joi or JSON Schema) then your my-module would have to be either:

let values = { a: 1, b: 2, c: 3 }
let {a, b, c} = values;
export {a, b, c};

Or:

let values = { a: 1, b: 2, c: 3 }
export let {a, b, c} = values;

Not pretty, but it compiles to what you need.

See: Babel example