Programs & Examples On #Dcommit

dcommit is the command used by git-svn to commit changes to a subversion repository.

Removing numbers from string

Just a few (others have suggested some of these)

Method 1:

''.join(i for i in myStr if not i.isdigit())

Method 2:

def removeDigits(s):
    answer = []
    for char in s:
        if not char.isdigit():
            answer.append(char)
    return ''.join(char)

Method 3:

''.join(filter(lambda x: not x.isdigit(), mystr))

Method 4:

nums = set(map(int, range(10)))
''.join(i for i in mystr if i not in nums)

Method 5:

''.join(i for i in mystr if ord(i) not in range(48, 58))

Submit Button Image

<INPUT TYPE="image" SRC="images/submit.gif" HEIGHT="30" WIDTH="173" BORDER="0" ALT="Submit Form">
Where the standard submit button has TYPE="submit", we now have TYPE="image". The image type is by default a form submitting button. More simple

installing python packages without internet and using source code as .tar.gz and .whl

pipdeptree is a command line utility for displaying the python packages installed in an virtualenv in form of a dependency tree. Just use it: https://github.com/naiquevin/pipdeptree

How to put a text beside the image?

If you or some other fox who need to have link with Icon Image and text as link text beside the image see bellow code:

CSS

.linkWithImageIcon{

    Display:inline-block;
}
.MyLink{
  Background:#FF3300;
  width:200px;
  height:70px;
  vertical-align:top;
  display:inline-block; font-weight:bold;
} 

.MyLinkText{
  /*---The margin depends on how the image size is ---*/
  display:inline-block; margin-top:5px;
}

HTML

<a href="#" class="MyLink"><img src="./yourImageIcon.png" /><span class="MyLinkText">SIGN IN</span></a>

enter image description here

if you see the image the white portion is image icon and other is style this way you can create different buttons with any type of Icons you want to design

Structure of a PDF file?

If You want to parse PDF using Python please have a look at PDFMINER. This is the best library to parse PDF files till date.

.gitignore exclude folder but include specific subfolder

There are a bunch of similar questions about this, so I'll post what I wrote before:

The only way I got this to work on my machine was to do it this way:

# Ignore all directories, and all sub-directories, and it's contents:
*/*

#Now ignore all files in the current directory 
#(This fails to ignore files without a ".", for example 
#'file.txt' works, but 
#'file' doesn't):
*.*

#Only Include these specific directories and subdirectories:
!wordpress/
!wordpress/*/
!wordpress/*/wp-content/
!wordpress/*/wp-content/themes/
!wordpress/*/wp-content/themes/*
!wordpress/*/wp-content/themes/*/*
!wordpress/*/wp-content/themes/*/*/*
!wordpress/*/wp-content/themes/*/*/*/*
!wordpress/*/wp-content/themes/*/*/*/*/*

Notice how you have to explicitly allow content for each level you want to include. So if I have subdirectories 5 deep under themes, I still need to spell that out.

This is from @Yarin's comment here: https://stackoverflow.com/a/5250314/1696153

These were useful topics:

I also tried

*
*/*
**/**

and **/wp-content/themes/**

or /wp-content/themes/**/*

None of that worked for me, either. Lots of trial and error!

standard_init_linux.go:190: exec user process caused "no such file or directory" - Docker

I found a particular edge case where I was using the tini init in an alpine container, but since I was not using the statically linked version, and Alpine uses musl libc rather than GNU LibC library installed by default, it was crashing with the very same error message.

Had I understood this and also taken time to read the documentation properly, I would have found Tini Static, which upon changing to, resolved my problem.

How to perform string interpolation in TypeScript?

Just use special `

var lyrics = 'Never gonna give you up';
var html = `<div>${lyrics}</div>`;

You can see more examples here.

Get a UTC timestamp

"... that are independent of their timezone"

var timezone =  d.getTimezoneOffset() // difference in minutes from GMT

How to copy data to clipboard in C#

My Experience with this issue using WPF C# coping to clipboard and System.Threading.ThreadStateException is here with my code that worked correctly with all browsers:

Thread thread = new Thread(() => Clipboard.SetText("String to be copied to clipboard"));
thread.SetApartmentState(ApartmentState.STA); //Set the thread to STA
thread.Start(); 
thread.Join();

credits to this post here

But this works only on localhost, so don't try this on a server, as it's not going to work.

On server-side, I did it by using zeroclipboard. The only way, after a lot of research.

Cannot open Windows.h in Microsoft Visual Studio

1) Go to C:\Program Files (x86)\Microsoft SDKs\Windows\v7.1A for VS2013

2) Copy the folders Include and Lib (you should check where are your folders in folder windows such as v7.1, v8, v6, etc.)

3) Paste them into C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC

I solved my problems like:

error lnk1104: cannot open file 'kernel32.lib'.
error c1083: Cannot open Windows.h

Thanks.

How to get HttpContext.Current in ASP.NET Core?

There is a solution to this if you really need a static access to the current context. In Startup.Configure(….)

app.Use(async (httpContext, next) =>
{
    CallContext.LogicalSetData("CurrentContextKey", httpContext);
    try
    {
        await next();
    }
    finally
    {
        CallContext.FreeNamedDataSlot("CurrentContextKey");
    }
});

And when you need it you can get it with :

HttpContext context = CallContext.LogicalGetData("CurrentContextKey") as HttpContext;

I hope that helps. Keep in mind this workaround is when you don’t have a choice. The best practice is to use de dependency injection.

Align Bootstrap Navigation to Center

Try this css

.clearfix:before, .clearfix:after, .container:before, .container:after, .container-fluid:before, .container-fluid:after, .row:before, .row:after, .form-horizontal .form-group:before, .form-horizontal .form-group:after, .btn-toolbar:before, .btn-toolbar:after, .btn-group-vertical > .btn-group:before, .btn-group-vertical > .btn-group:after, .nav:before, .nav:after, .navbar:before, .navbar:after, .navbar-header:before, .navbar-header:after, .navbar-collapse:before, .navbar-collapse:after, .pager:before, .pager:after, .panel-body:before, .panel-body:after, .modal-footer:before, .modal-footer:after {
    content: " ";
    display: table-cell;
}

ul.nav {
    float: none;
    margin-bottom: 0;
    margin-left: auto;
    margin-right: auto;
    margin-top: 0;
    width: 240px;
}

unable to install pg gem

This worked in my case:

sudo apt-get install libpq-dev

I used:

  • Ubuntu 14.04.2 LTS
  • Ruby 2.2.2
  • Rails 4.2.1

Getting "The remote certificate is invalid according to the validation procedure" when SMTP server has a valid certificate

Old post, but I thought I would share my solution because there aren't many solutions out there for this issue.

If you're running an old Windows Server 2003 machine, you likely need to install a hotfix (KB938397).

This problem occurs because the Cryptography API 2 (CAPI2) in Windows Server 2003 does not support the SHA2 family of hashing algorithms. CAPI2 is the part of the Cryptography API that handles certificates.

https://support.microsoft.com/en-us/kb/938397

For whatever reason, Microsoft wants to email you this hotfix instead of allowing you to download directly. Here's a direct link to the hotfix from the email:

http://hotfixv4.microsoft.com/Windows Server 2003/sp3/Fix200653/3790/free/315159_ENU_x64_zip.exe

How to select all the columns of a table except one column?

You can get the column name details from sys.columns table

Try the following query:

SELECT * FROM SYS.COLUMNS 
WHERE object_id = OBJECT_ID('dbo.TableName') 
AND [Name] <> 'ColumnName'

DECLARE @sql as VARCHAR(8000)
SET @sql = 'SELECT '

SELECT @sql += [Name] + ', ' FROM SYS.COLUMNS 
WHERE object_id = OBJECT_ID('dbo.TableName') 
AND [Name] <> 'ColumnName'

SELECT @sql += ' FROM Dbo.TableName'

EXEC(@sql)

A SELECT statement that assigns a value to a variable must not be combined with data-retrieval operations

declare @cur cursor
declare @idx int       
declare @Approval_No varchar(50) 

declare @ReqNo varchar(100)
declare @M_Id  varchar(100)
declare @Mail_ID varchar(100)
declare @temp  table
(
val varchar(100)
)
declare @temp2  table
(
appno varchar(100),
mailid varchar(100),
userod varchar(100)
)


    declare @slice varchar(8000)       
    declare @String varchar(100)
    --set @String = '1200096,1200095,1200094,1200093,1200092,1200092'
set @String = '20131'


    select @idx = 1       
        if len(@String)<1 or @String is null  return       

    while @idx!= 0       
    begin       
        set @idx = charindex(',',@String)       
        if @idx!=0       
            set @slice = left(@String,@idx - 1)       
        else       
            set @slice = @String

            --select @slice       
            insert into @temp values(@slice)
        set @String = right(@String,len(@String) - @idx)       
        if len(@String) = 0 break


    end
    -- select distinct(val) from @temp


SET @cur = CURSOR FOR select distinct(val) from @temp


--open cursor    
OPEN @cur    
--fetchng id into variable    
FETCH NEXT    
    FROM @cur into @Approval_No 

      --
    --loop still the end    
     while @@FETCH_STATUS = 0  
    BEGIN   


select distinct(Approval_Sr_No) as asd, @ReqNo=Approval_Sr_No,@M_Id=AM_ID,@Mail_ID=Mail_ID from WFMS_PRAO,WFMS_USERMASTER where  WFMS_PRAO.AM_ID=WFMS_USERMASTER.User_ID
and Approval_Sr_No=@Approval_No

   insert into @temp2 values(@ReqNo,@M_Id,@Mail_ID)  

FETCH NEXT    
      FROM @cur into @Approval_No    
 end  
    --close cursor    
    CLOSE @cur    

select * from @tem

How Do I Insert a Byte[] Into an SQL Server VARBINARY Column

You can do something like this, very simple and efficient solution: What i did was actually use a parameter instead of basic placeholder, created a SqlParameter object and used another existing execution method. For e.g in your scenario:

string sql = "INSERT INTO mssqltable (varbinarycolumn) VALUES (@img)";
SqlParameter param = new SqlParameter("img", arraytoinsert); //where img is your parameter name in the query
ExecuteStoreCommand(sql, param);

This should work like a charm, provided you have an open sql connection established.

Fetching distinct values on a column using Spark DataFrame

Well to obtain all different values in a Dataframe you can use distinct. As you can see in the documentation that method returns another DataFrame. After that you can create a UDF in order to transform each record.

For example:

val df = sc.parallelize(Array((1, 2), (3, 4), (1, 6))).toDF("age", "salary")

// I obtain all different values. If you show you must see only {1, 3}
val distinctValuesDF = df.select(df("age")).distinct

// Define your udf. In this case I defined a simple function, but they can get complicated.
val myTransformationUDF = udf(value => value / 10)

// Run that transformation "over" your DataFrame
val afterTransformationDF = distinctValuesDF.select(myTransformationUDF(col("age")))

Is it safe to use Project Lombok?

I read some opinions about the Lombok and actually I'm using it in some projects.

Well, in the first contact with Lombok I had a bad impression. After some weeks, I started to like it. But after some months I figure out a lot of tiny problems using it. So, my final impression about Lombok is not so positive.

My reasons to think in this way:

  • IDE plugin dependency. The IDE support for Lombok is through plugins. Even working good in most part of the time, you are always a hostage from this plugins to be maintained in the future releases of the IDEs and even the language version (Java 10+ will accelerate the development of the language). For example, I tried to update from Intellij IDEA 2017.3 to 2018.1 and I couldn't do that because there was some problem on the actual lombok plugin version and I needed to wait the plugin be updated... This also is a problem if you would like to use a more alternative IDE that don't have any Lombok plugin support.
  • 'Find usages' problem.. Using Lombok you don't see the generated getter, setter, constructor, builder methods and etc. So, if you are planning to find out where these methods are being used in your project by your IDE, you can't do this only looking for the class that owns this hidden methods.
  • So easy that the developers don't care to break the encapsulation. I know that it's not really a problem from Lombok. But I saw a bigger tendency from the developers to not control anymore what methods needs to be visible or not. So, many times they are just copying and pasting @Getter @Setter @Builder @AllArgsConstructor @NoArgsConstructor annotations block without thinking what methods the class really need to be exposed.
  • Builder Obssession ©. I invented this name (get off, Martin Fowler). Jokes apart, a Builder is so easy to create that even when a class have only two parameters the developers prefer to use @Builder instead of constructor or a static constructor method. Sometimes they even try to create a Builder inside the lombok Builder, creating weird situations like MyClass.builder().name("Name").build().create().
  • Barriers when refactoring. If you are using, for example, a @AllArgsConstructor and need to add one more parameter on the constructor, the IDE can't help you to add this extra parameter in all places (mostly, tests) that are instantiating the class.
  • Mixing Lombok with concrete methods. You can't use Lombok in all scenarios to create a getter/setter/etc. So, you will see these two approaches mixed in your code. You get used to this after some time, but feels like a hack on the language.

Like another answer said, if you are angry about the Java verbosity and use Lombok to deal with it, try Kotlin.

How to delete all files and folders in a folder by cmd call

To delete file:

del PATH_TO_FILE

To delete folder with all files in it:

rmdir /s /q PATH_TO_FOLDER

To delete all files from specific folder (not deleting folder itself) is a little bit complicated. del /s *.* cannot delete folders, but removes files from all subfolder. So two commands are needed:

del /q PATH_TO_FOLDER\*.*
for /d %i in (PATH_TO_FOLDER\*.*) do @rmdir /s /q "%i"

You can create a script to delete whatever you want (folder or file) like this mydel.bat:

@echo off
setlocal enableextensions

if "%~1"=="" (
    echo Usage: %0 path
    exit /b 1
)

:: check whether it is folder or file
set ISDIR=0
set ATTR=%~a1
set DIRATTR=%ATTR:~0,1%
if /i "%DIRATTR%"=="d" set ISDIR=1

:: Delete folder or file
if %ISDIR%==1 (rmdir /s /q "%~1") else (del "%~1")
exit /b %ERRORLEVEL%

Few example of usage:

mydel.bat "path\to\folder with spaces"
mydel.bat path\to\file_or_folder

Python vs Cpython

You should know that CPython doesn't really support multithreading (it does, but not optimal) because of the Global Interpreter Lock. It also has no Optimisation mechanisms for recursion, and has many other limitations that other implementations and libraries try to fill.

You should take a look at this page on the python wiki.

Look at the code snippets on this page, it'll give you a good idea of what an interpreter is.

Regex to check if valid URL that ends in .jpg, .png, or .gif

(http(s?):)|([/|.|\w|\s])*\.(?:jpg|gif|png)

This will mach all images from this string:

background: rgb(255, 0, 0) url(../res/img/temp/634043/original/cc3d8715eed0c.jpg) repeat fixed left top; cursor: auto;
<div id="divbg" style="background-color:#ff0000"><img id="bg" src="../res/img/temp/634043/original/cc3d8715eed0c.jpg" width="100%" height="100%" /></div>
background-image: url(../res/img/temp/634043/original/cc3d8715eed0c.png);
background: rgb(255, 0, 0) url(http://google.com/res/../img/temp/634043/original/cc3    _d8715eed0c.jpg) repeat fixed left top; cursor: auto;
background: rgb(255, 0, 0) url(https://google.com/res/../img/temp/634043/original/cc3_d8715eed0c.jpg) repeat fixed left top; cursor: auto;

Test your regex here: https://regex101.com/r/l2Zt7S/1

How to declare a type as nullable in TypeScript?

You can just implement a user-defined type like the following:

type Nullable<T> = T | undefined | null;

var foo: Nullable<number> = 10; // ok
var bar: Nullable<number> = true; // type 'true' is not assignable to type 'Nullable<number>'
var baz: Nullable<number> = null; // ok

var arr1: Nullable<Array<number>> = [1,2]; // ok
var obj: Nullable<Object> = {}; // ok

 // Type 'number[]' is not assignable to type 'string[]'. 
 // Type 'number' is not assignable to type 'string'
var arr2: Nullable<Array<string>> = [1,2];

How to show shadow around the linearlayout in Android?

Well, this is easy to achieve .

Just build a GradientDrawable that comes from black and goes to a transparent color, than use parent relationship to place your shape close to the View that you want to have a shadow, then you just have to give any values to height or width .

Here is an example, this file have to be created inside res/drawable , I name it as shadow.xml :

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <gradient
        android:startColor="#9444"
        android:endColor="#0000"
        android:type="linear"
        android:angle="90"> <!-- Change this value to have the correct shadow angle, must be multiple from 45 -->
    </gradient>

</shape>

Place the following code above from a LinearLayout , for example, set the android:layout_width and android:layout_height to fill_parent and 2.3dp, you'll have a nice shadow effect on your LinearLayout .

<View
    android:id="@+id/shadow"
    android:layout_width="fill_parent"
    android:layout_height="2.3dp"  
    android:layout_above="@+id/id_from_your_LinearLayout" 
    android:background="@drawable/shadow">
</View>

Note 1: If you increase android:layout_height more shadow will be shown .

Note 2: Use android:layout_above="@+id/id_from_your_LinearLayout" attribute if you are placing this code inside a RelativeLayout, otherwise ignore it.

Hope it help someone.

"Stack overflow in line 0" on Internet Explorer

My was "at line 1" instead but...

I got this problem when using jQuery's .clone method. I replaced these by using making jQuery objects from the html string: $($(selector).html()).

Vue template or render function not defined yet I am using neither?

Yet another idea to throw in to the mix... In my case, the component throwing the error was a template-less component with a custom render() function. I couldn't see why it wasn't working, until I realised that I hadn't put <script>...</script> tags around the code in the component (seemed unnecessary, since I had no template or style tags either). Not sure why this got past the compiler...?

Either way... make sure you use your <script> tags ;-)

How to view the assembly behind the code using Visual C++?

Red Gate's .NET Reflector is a pretty awesome tool that has helped me out more than a few times. The plus side of this utility outside of easily showing you MSIL is that you can analyze a lot of third-party DLLs and have the Reflector take care of converting MSIL to C# and VB.

I'm not promising the code will be as clear as source but you shouldn't have much trouble following it.

Call a REST API in PHP

You will need to know if the REST API you are calling supports GET or POST, or both methods. The code below is something that works for me, I'm calling my own web service API, so I already know what the API takes and what it will return. It supports both GET and POST methods, so the less sensitive info goes into the URL (GET), and the info like username and password is submitted as POST variables. Also, everything goes over the HTTPS connection.

Inside the API code, I encode an array I want to return into json format, then simply use PHP command echo $my_json_variable to make that json string availabe to the client.

So as you can see, my API returns json data, but you need to know (or look at the returned data to find out) what format the response from the API is in.

This is how I connect to the API from the client side:

$processed = FALSE;
$ERROR_MESSAGE = '';

// ************* Call API:
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://www.myapi.com/api.php?format=json&action=subscribe&email=" . $email_to_subscribe);
curl_setopt($ch, CURLOPT_POST, 1);// set post data to true
curl_setopt($ch, CURLOPT_POSTFIELDS,"username=myname&password=mypass");   // post data
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$json = curl_exec($ch);
curl_close ($ch);

// returned json string will look like this: {"code":1,"data":"OK"}
// "code" may contain an error code and "data" may contain error string instead of "OK"
$obj = json_decode($json);

if ($obj->{'code'} == '1')
{
  $processed = TRUE;
}else{
  $ERROR_MESSAGE = $obj->{'data'};
}

...

if (!$processed && $ERROR_MESSAGE != '') {
    echo $ERROR_MESSAGE;
}

BTW, I also tried to use file_get_contents() method as some of the users here suggested, but that din't work well for me. I found out the curl method to be faster and more reliable.

version `CXXABI_1.3.8' not found (required by ...)

GCC 4.9 introduces a newer C++ ABI version than your system libstdc++ has, so you need to tell the loader to use this newer version of the library by adding that path to LD_LIBRARY_PATH. Unfortunately, I cannot tell you straight off where the libstdc++ so for your GCC 4.9 installation is located, as this depends on how you configured GCC. So you need something in the style of:

export LD_LIBRARY_PATH=/home/user/lib/gcc-4.9.0/lib:/home/user/lib/boost_1_55_0/stage/lib:$LD_LIBRARY_PATH

Note the actual path may be different (there might be some subdirectory hidden under there, like `x86_64-unknown-linux-gnu/4.9.0´ or similar).

Eclipse: Syntax Error, parameterized types are only if source level is 1.5

This works for me .

In eclipse go to project properties -> java compiler.

Then change to java higher than 1.5 .

change Compiler compliance settings to 1.6 change Generated.class files compatibility to 1.6 change Source compatibility to 1.6

Thanks. Screen Shot for changes

How to assign the output of a command to a Makefile variable

With GNU Make, you can use shell and eval to store, run, and assign output from arbitrary command line invocations. The difference between the example below and those which use := is the := assignment happens once (when it is encountered) and for all. Recursively expanded variables set with = are a bit more "lazy"; references to other variables remain until the variable itself is referenced, and the subsequent recursive expansion takes place each time the variable is referenced, which is desirable for making "consistent, callable, snippets". See the manual on setting variables for more info.

# Generate a random number.
# This is not run initially.
GENERATE_ID = $(shell od -vAn -N2 -tu2 < /dev/urandom)

# Generate a random number, and assign it to MY_ID
# This is not run initially.
SET_ID = $(eval MY_ID=$(GENERATE_ID))

# You can use .PHONY to tell make that we aren't building a target output file
.PHONY: mytarget
mytarget:
# This is empty when we begin
    @echo $(MY_ID)
# This recursively expands SET_ID, which calls the shell command and sets MY_ID
    $(SET_ID)
# This will now be a random number
    @echo $(MY_ID)
# Recursively expand SET_ID again, which calls the shell command (again) and sets MY_ID (again)
    $(SET_ID)
# This will now be a different random number
    @echo $(MY_ID)

How to extract text from a PDF?

On my Macintosh systems, I find that "Adobe Reader" does a reasonably good job. I created an alias on my Desktop that points to the "Adobe Reader.app", and all I do is drop a pdf-file on the alias, which makes it the active document in Adobe Reader, and then from the File-menu, I choose "Save as Text...", give it a name and where to save it, click "Save", and I'm done.

How to have css3 animation to loop forever

add this styles

animation-iteration-count:infinite;

How to use vagrant in a proxy environment?

If you actually do want your proxy configurations and plugin installations to be in your Vagrantfile, for example if you're making a Vagrantfile just for your corporate environment and can't have users editing environment variables, this was the answer for me:

ENV['http_proxy']  = 'http://proxyhost:proxyport'
ENV['https_proxy'] = 'http://proxyhost:proxyport'

# Plugin installation procedure from http://stackoverflow.com/a/28801317
required_plugins = %w(vagrant-proxyconf)

plugins_to_install = required_plugins.select { |plugin| not Vagrant.has_plugin? plugin }
if not plugins_to_install.empty?
  puts "Installing plugins: #{plugins_to_install.join(' ')}"
  if system "vagrant plugin install #{plugins_to_install.join(' ')}"
    exec "vagrant #{ARGV.join(' ')}"
  else
    abort "Installation of one or more plugins has failed. Aborting."
  end
end

Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
  config.proxy.http     = "#{ENV['http_proxy']}"
  config.proxy.https    = "#{ENV['https_proxy']}"
  config.proxy.no_proxy = "localhost,127.0.0.1"
  # and so on

(If you don't, just set them as environment variables like the other answers say and refer to them from env in config.proxy.http(s) directives.)

Java: Enum parameter in method

This should do it:

private enum Alignment { LEFT, RIGHT };    
String drawCellValue (int maxCellLength, String cellValue, Alignment align){
  if (align == Alignment.LEFT)
  {
    //Process it...
  }
}

getActivity() returns null in Fragment function

commit schedules the transaction, i.e. it doesn't happen straightaway but is scheduled as work on the main thread the next time the main thread is ready.

I'd suggest adding an

onAttach(Activity activity)

method to your Fragment and putting a break point on it and seeing when it is called relative to your call to asd(). You'll see that it is called after the method where you make the call to asd() exits. The onAttach call is where the Fragment is attached to its activity and from this point getActivity() will return non-null (nb there is also an onDetach() call).

How to format dateTime in django template?

You can use this:

addedDate = datetime.now().replace(microsecond=0)

What is the total amount of public IPv4 addresses?

https://www.ripe.net/internet-coordination/press-centre/understanding-ip-addressing

For IPv4, this pool is 32-bits (2³²) in size and contains 4,294,967,296 IPv4 addresses.

In case of IPv6

The IPv6 address space is 128-bits (2¹²8) in size, containing 340,282,366,920,938,463,463,374,607,431,768,211,456 IPv6 addresses.

inclusive of RESERVED IP

 Reserved address blocks
 Range  Description Reference

 0.0.0.0/8  Current network (only valid as source address)  RFC 6890
 10.0.0.0/8 Private network RFC 1918
 100.64.0.0/10  Shared Address Space    RFC 6598
 127.0.0.0/8    Loopback    RFC 6890
 169.254.0.0/16 Link-local  RFC 3927
 172.16.0.0/12  Private network RFC 1918
 192.0.0.0/24   IETF Protocol Assignments   RFC 6890
 192.0.2.0/24   TEST-NET-1, documentation and examples  RFC 5737
 192.88.99.0/24 IPv6 to IPv4 relay (includes 2002::/16) RFC 3068
 192.168.0.0/16 Private network RFC 1918
 198.18.0.0/15  Network benchmark tests RFC 2544
 198.51.100.0/24    TEST-NET-2, documentation and examples  RFC 5737
 203.0.113.0/24 TEST-NET-3, documentation and examples  RFC 5737
 224.0.0.0/4    IP multicast (former Class D network)   RFC 5771
 240.0.0.0/4    Reserved (former Class E network)   RFC 1700
 255.255.255.255    Broadcast   RFC 919

wiki has full details and this has details of IPv6.

C++ catching all exceptions

try{
    // ...
} catch (...) {
    // ...
}

will catch all C++ exceptions, but it should be considered bad design. You can use c++11's new current_exception mechanism, but if you don't have the ability to use c++11 (legacy code systems requiring a rewrite), then you have no named exception pointer to use to get a message or name. You may want to add separate catch clauses for the various exceptions you can catch, and only catch everything at the bottom to record an unexpected exception. E.g.:

try{
    // ...
} catch (const std::exception& ex) {
    // ...
} catch (const std::string& ex) {
    // ...
} catch (...) {
    // ...
}

Find and extract a number from a string

You can do this using String property like below:

 return new String(input.Where(Char.IsDigit).ToArray()); 

which gives only number from string.

Negation in Python

Combining the input from everyone else (use not, no parens, use os.mkdir) you'd get...

special_path_for_john = "/usr/share/sounds/blues"
if not os.path.exists(special_path_for_john):
    os.mkdir(special_path_for_john)

PHP - Check if two arrays are equal

Another method for checking equality regardless of value order works by using http://php.net/manual/en/function.array-intersect.php, like so:

$array1 = array(2,5,3);
$array2 = array(5,2,3);
if($array1 === array_intersect($array1, $array2) && $array2 === array_intersect($array2, $array1)) {
    echo 'Equal';
} else {
    echo 'Not equal';
}

Here's a version that works also with multidimensional arrays using http://php.net/manual/en/function.array-uintersect.php:

$array1 = array(
    array(5, 2),
    array(3, 6),
    array(2, 9, 4)
);
$array2 = array(
    array(3, 6),
    array(2, 9, 4),
    array(5, 2)
);

if($array1 === array_uintersect($array1, $array2, 'compare') && $array2 === array_uintersect($array2, $array1, 'compare')) {
    echo 'Equal';
} else {
    echo 'Not equal';
}

function compare($v1, $v2) {
    if ($v1===$v2) {
        return 0;
    }
    if ($v1 > $v2) return 1;
    return -1;
}

Converting string to byte array in C#

You could use MemoryMarshal API to perform very fast and efficient conversion. String will implicitly be cast to ReadOnlySpan<byte>, as MemoryMarshal.Cast accepts either Span<byte> or ReadOnlySpan<byte> as an input parameter.

public static class StringExtensions
{
    public static byte[] ToByteArray(this string s) => s.ToByteSpan().ToArray(); //  heap allocation, use only when you cannot operate on spans
    public static ReadOnlySpan<byte> ToByteSpan(this string s) => MemoryMarshal.Cast<char, byte>(s);
}

Following benchmark shows the difference:

Input: "Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s,"

|                       Method |       Mean |     Error |    StdDev |  Gen 0 | Gen 1 | Gen 2 | Allocated |
|----------------------------- |-----------:|----------:|----------:|-------:|------:|------:|----------:|
| UsingEncodingUnicodeGetBytes | 160.042 ns | 3.2864 ns | 6.4099 ns | 0.0780 |     - |     - |     328 B |
| UsingMemoryMarshalAndToArray |  31.977 ns | 0.7177 ns | 1.5753 ns | 0.0781 |     - |     - |     328 B |
|           UsingMemoryMarshal |   1.027 ns | 0.0565 ns | 0.1630 ns |      - |     - |     - |         - |

Get element of JS object with an index

Object.keys(city)[0];   //return the key name at index 0
Object.values(city)[0]  //return the key values at index 0

Can a java lambda have more than 1 parameter?

For something with 2 parameters, you could use BiFunction. If you need more, you can define your own function interface, like so:

@FunctionalInterface
public interface FourParameterFunction<T, U, V, W, R> {
    public R apply(T t, U u, V v, W w);
}

If there is more than one parameter, you need to put parentheses around the argument list, like so:

FourParameterFunction<String, Integer, Double, Person, String> myLambda = (a, b, c, d) -> {
    // do something
    return "done something";
};

Access Https Rest Service using Spring RestTemplate

One point from me. I used a mutual cert authentication with spring-boot microservices. The following is working for me, key points here are keyManagerFactory.init(...) and sslcontext.init(keyManagerFactory.getKeyManagers(), null, new SecureRandom()) lines of code without them, at least for me, things did not work. Certificates are packaged by PKCS12.

@Value("${server.ssl.key-store-password}")
private String keyStorePassword;
@Value("${server.ssl.key-store-type}")
private String keyStoreType;
@Value("${server.ssl.key-store}")
private Resource resource;

private RestTemplate getRestTemplate() throws Exception {
    return new RestTemplate(clientHttpRequestFactory());
}

private ClientHttpRequestFactory clientHttpRequestFactory() throws Exception {
    return new HttpComponentsClientHttpRequestFactory(httpClient());
}

private HttpClient httpClient() throws Exception {

    KeyManagerFactory keyManagerFactory = KeyManagerFactory.getInstance("SunX509");
    KeyStore trustStore = KeyStore.getInstance(keyStoreType);

    if (resource.exists()) {
        InputStream inputStream = resource.getInputStream();

        try {
            if (inputStream != null) {
                trustStore.load(inputStream, keyStorePassword.toCharArray());
                keyManagerFactory.init(trustStore, keyStorePassword.toCharArray());
            }
        } finally {
            if (inputStream != null) {
                inputStream.close();
            }
        }
    } else {
        throw new RuntimeException("Cannot find resource: " + resource.getFilename());
    }

    SSLContext sslcontext = SSLContexts.custom().loadTrustMaterial(trustStore, new TrustSelfSignedStrategy()).build();
    sslcontext.init(keyManagerFactory.getKeyManagers(), null, new SecureRandom());
    SSLConnectionSocketFactory sslConnectionSocketFactory =
            new SSLConnectionSocketFactory(sslcontext, new String[]{"TLSv1.2"}, null, getDefaultHostnameVerifier());

    return HttpClients.custom().setSSLSocketFactory(sslConnectionSocketFactory).build();
}

How to create a responsive image that also scales up in Bootstrap 3

Bootstrap's responsive image class sets max-width to 100%. This limits its size, but does not force it to stretch to fill parent elements larger than the image itself. You'd have to use the width attribute to force upscaling.

http://getbootstrap.com/css/#images-responsive

how to implement login auth in node.js

To add to Farid's pseudo-answer,

Consider using Passport.js over everyauth.

The answers to this question provide some insight to the differences.


There are plenty of benefits to offloading your user authentication to Google, Facebook or another website. If your application's requirements are such that you could use Passport as your sole authentication provider or alongside traditional login, it can make the experience easier for your users.

What process is listening on a certain port on Solaris?

#!/usr/bin/bash
# This is a little script based on the "pfiles" solution that prints the PID and PORT.

pfiles `ls /proc` 2>/dev/null | awk "/^[^ \\t]/{smatch=\$0;next}/port:[ \\t]*${1}/{print smatch, \$0}{next}"

How do you make Vim unhighlight what you searched for?

There is hlsearch and nohlsearch. :help hlsearch will provide more information.

If you want to bind F12 to toggle it on/off you can use this:

map     <F12>   :nohlsearch<CR>
imap    <F12>   <ESC>:nohlsearch<CR>i
vmap    <F12>   <ESC>:nohlsearch<CR>gv

How to make an ng-click event conditional?

I had this issue also and I simply found out that if you simply remove the "#" the issue goes off. Like this :

<a href="" class="disabled" ng-click="doSomething(object)">Do something</a>

Strange problem with Subversion - "File already exists" when trying to recreate a directory that USED to be in my repository

already had this type of problem.

my solution was:

delete the folder from svn but keep a copy of the folder somewhere, commit the changes. in the backup-copy, delete recursively all the .svn-folders in it. for this you might run

#!/bin/bash

find -name '.svn' | while read directory;
do
    echo $directory;
    rm -rf "$directory";
done;

delete the local repository and re-check out entire project. don't know whether partial deletion/checkout are sufficient.

regards

Unable to connect to SQL Server instance remotely

I recently upgraded from SQL 2008 R2 to SQL 2012 and had a similar issue. The problem was the firewall, but more specifically the firewall rule for SQL SERVER. The custom rule was pointed to the prior version of SQL Server. Try this, open Windows Firewall>Advanced setting. Find the SQL Server Rule (it may have a custom name). Right-Click and go to properties, then Programs and Services Tab. If Programs-This program is selected, you should browse for the proper version of sqlserver.exe.

Hexadecimal value 0x00 is a invalid character

In my case, it took some digging, but found it.

My Context

I'm looking at exception/error logs from the website using Elmah. Elmah returns the state of the server at the of time the exception, in the form of a large XML document. For our reporting engine I pretty-print the XML with XmlWriter.

During a website attack, I noticed that some xmls weren't parsing and was receiving this '.', hexadecimal value 0x00, is an invalid character. exception.

NON-RESOLUTION: I converted the document to a byte[] and sanitized it of 0x00, but it found none.

When I scanned the xml document, I found the following:

...
<form>
...
<item name="SomeField">
   <value
     string="C:\boot.ini&#x0;.htm" />
 </item>
...

There was the nul byte encoded as an html entity &#x0; !!!

RESOLUTION: To fix the encoding, I replaced the &#x0; value before loading it into my XmlDocument, because loading it will create the nul byte and it will be difficult to sanitize it from the object. Here's my entire process:

XmlDocument xml = new XmlDocument();
details.Xml = details.Xml.Replace("&#x0;", "[0x00]");  // in my case I want to see it, otherwise just replace with ""
xml.LoadXml(details.Xml);

string formattedXml = null;

// I have this in a helper function, but for this example I have put it in-line
StringBuilder sb = new StringBuilder();
XmlWriterSettings settings = new XmlWriterSettings {
    OmitXmlDeclaration = true,
    Indent = true,
    IndentChars = "\t",
    NewLineHandling = NewLineHandling.None,
};
using (XmlWriter writer = XmlWriter.Create(sb, settings)) {
    xml.Save(writer);
    formattedXml = sb.ToString();
}

LESSON LEARNED: sanitize for illegal bytes using the associated html entity, if your incoming data is html encoded on entry.

Print directly from browser without print popup window

I don't believe this is possible. The dialog box that gets displayed allows the user to select a printer to print to. So, let's say it would be possible for your application to just click and print, and a user clicks your print button, but has two printers connected to the computer. Or, more likely, that user is working in an office building with 25 printers. Without that dialog box, how would the computer know to which printer to print?

Error: No Firebase App '[DEFAULT]' has been created - call Firebase App.initializeApp()

If you are starting out a react-native app and seeing this issue, then you have to follow all the instructions listed in firebase (when you setup iOS/android app) or the instructions @ React-native google auth android DEVELOPER_ERROR Code 10 question

enter image description here

How to get attribute of element from Selenium?

Python

element.get_attribute("attribute name")

Java

element.getAttribute("attribute name")

Ruby

element.attribute("attribute name")

C#

element.GetAttribute("attribute name");

SSL error : routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed

Got this issue today and after wandering for several hours just came to know that my server datetime was wrong.

So first please check your server datetime before going so deep in this issue.

also try doing

>> sudo update-ca-certificates

Warning: The method assertEquals from the type Assert is deprecated

this method also encounter a deprecate warning:

org.junit.Assert.assertEquals(float expected,float actual) //deprecated

It is because currently junit prefer a third parameter rather than just two float variables input.

The third parameter is delta:

public static void assertEquals(double expected,double actual,double delta) //replacement

this is mostly used to deal with inaccurate Floating point calculations

for more information, please refer this problem: Meaning of epsilon argument of assertEquals for double values

Subtract two dates in Java

Date d1 = new SimpleDateFormat("yyyy-M-dd").parse((String) request.
            getParameter(date1));
Date d2 = new SimpleDateFormat("yyyy-M-dd").parse((String) request.
            getParameter(date2));

long diff = d2.getTime() - d1.getTime();

System.out.println("Difference between  " + d1 + " and "+ d2+" is "
        + (diff / (1000 * 60 * 60 * 24)) + " days.");

Installing Python 2.7 on Windows 8

i'm using python 2.7 in win 8 too but no problem with that. maybe you need to reastart your computer like wclear said, or you can run python command line program that included in python installation folder, i think below IDLE program. hope it help.

Error: Main method not found in class Calculate, please define the main method as: public static void main(String[] args)

you seem to have not created an main method, which should probably look something like this (i am not sure)

  class RunThis
{
    public static void main(String[] args)
    {

    Calculate answer = new Calculate();
    answer.getNumber1();
    answer.getNumber2();
    answer.setNumber(answer.getNumber1() , answer.getNumber2());
    answer.getOper();
    answer.setOper(answer.getOper());
    answer.getAnswer();
    }
}

the point is you should have created a main method under some class and after compiling you should run the .class file containing main method. In this case the main method is under RunThis i.e RunThis.class.

I am new to java this may or may not be the right answer, correct me if i am wrong

Unsafe JavaScript attempt to access frame with URL

I found that using the XFBML version of the Facebook like button instead of the HTML5 version fixed this problem. Add the below code where you want the button to appear:

<div id="fb-root"></div>
<script>(function (d, s, id) {
    var js, fjs = d.getElementsByTagName(s)[0];
    if (d.getElementById(id)) return;
    js = d.createElement(s); js.id = id;
    js.src = "//connect.facebook.net/en_GB/all.js#xfbml=1";
    fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));</script>

<fb:like send="true" layout="button_count" width="50" show_faces="false" font="arial"></fb:like>

Then add this to your HTML tag:

 xmlns:fb="http://ogp.me/ns/fb#"

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

function getMonthDays(MonthYear) {
  var months = [
    'January',
    'February',
    'March',
    'April',
    'May',
    'June',
    'July',
    'August',
    'September',
    'October',
    'November',
    'December'
  ];

  var Value=MonthYear.split(" ");      
  var month = (months.indexOf(Value[0]) + 1);      
  return new Date(Value[1], month, 0).getDate();
}

console.log(getMonthDays("March 2011"));

Show Youtube video source into HTML5 video tag?

Step 1: add &html5=True to your favorite youtube url

Step 2: Find <video/> tag in source

Step 3: Add controls="controls" to video tag: <video controls="controls"..../>

Example:

_x000D_
_x000D_
<video controls="controls" class="video-stream" x-webkit-airplay="allow" data-youtube-id="N9oxmRT2YWw" src="http://v20.lscache8.c.youtube.com/videoplayback?sparams=id%2Cexpire%2Cip%2Cipbits%2Citag%2Cratebypass%2Coc%3AU0hPRVRMVV9FSkNOOV9MRllD&amp;itag=43&amp;ipbits=0&amp;signature=D2BCBE2F115E68C5FF97673F1D797F3C3E3BFB99.59252109C7D2B995A8D51A461FF9A6264879948E&amp;sver=3&amp;ratebypass=yes&amp;expire=1300417200&amp;key=yt1&amp;ip=0.0.0.0&amp;id=37da319914f6616c"></video>
_x000D_
_x000D_
_x000D_

Note there seems to some expire stuff. I don't know how long the src string will work.

Still testing myself.

Edit (July 28, 2011): Note that this video src is specific to the browser you use to retrieve the page source. I think Youtube generates this HTML dynamically (at least currently) so in testing if I copy in Firefox this works in Firefox, but not Chrome, for example.

VNC viewer with multiple monitors

RealVNC 5.0.x now offers a VNCViewer that will do dual displays on Windows without having to buy a license. (Licensing now covers the SERVER portion of their tools).

How to insert array of data into mysql using php

First of all you should stop using mysql_*. MySQL supports multiple inserting like

INSERT INTO example
VALUES
  (100, 'Name 1', 'Value 1', 'Other 1'),
  (101, 'Name 2', 'Value 2', 'Other 2'),
  (102, 'Name 3', 'Value 3', 'Other 3'),
  (103, 'Name 4', 'Value 4', 'Other 4');

You just have to build one string in your foreach loop which looks like that

$values = "(100, 'Name 1', 'Value 1', 'Other 1'), (100, 'Name 1', 'Value 1', 'Other 1'), (100, 'Name 1', 'Value 1', 'Other 1')";

and then insert it after the loop

$sql = "INSERT INTO email_list (R_ID, EMAIL, NAME) VALUES ".$values;

Another way would be Prepared Statements, which are even more suited for your situation.

How to select a record and update it, with a single queryset in Django?

only in a case in serializer things, you can update in very simple way!

my_model_serializer = MyModelSerializer(
    instance=my_model, data=validated_data)
if my_model_serializer.is_valid():

    my_model_serializer.save()

only in a case in form things!

instance = get_object_or_404(MyModel, id=id)
form = MyForm(request.POST or None, instance=instance)
if form.is_valid():
    form.save()

How to write :hover condition for a:before and a:after?

Try to use .card-listing:hover::after hover and after using :: it wil work

How to block users from closing a window in Javascript?

It's poor practice to force the user to do something they don't necessarily want to do. You can't ever really prevent them from closing the browser.

You can achieve a similar effect, though, by making a div on your current web page to layer over top the rest of your controls so your form is the only thing accessible.

How to do tag wrapping in VS code?

  1. Open Keyboard Shortcuts by typing ? Command+k ? Command+s or Code > Preferences > Keyboard Shortcuts
  2. Type emmet wrap
  3. Click the plus sign to the left of "Emmet: Wrap with Abbreviation"
  4. Type ? Option+w
  5. Press Enter

Error: 'int' object is not subscriptable - Python

It would be a lot more simple just to do this;

name = input("What's your name? ")
age = int(input("How old are you? "))
print ("Hi,{0} you will be 21 in {1} years.".format(name, 21 - age))`

iPhone and WireShark

I had to do something very similar to find out why my iPhone was bleeding cellular network data, eating 80% of my 500Mb allowance in a couple of days.

Unfortunately I had to packet sniff whilst on 3G/4G and couldn't rely on being on wireless. So if you need an "industrial" solution then this is how you sniff all traffic (not just http) on any network.

Basic recipe:

  1. Install VPN server
  2. Run packet sniffer on VPN server
  3. Connect iPhone to VPN server and perform operations
  4. Download .pcap from VPN server and use your favourite .pcap analyser on it.

Detailed'ish instructions:

  1. Get yourself a linux server, I used Fedora 20 64bit from Digirtal Ocean on a $5/month box
  2. Configure OpenVPN on it. OpenVPN has comprehensive instructions
  3. Ensure you configure the Routing all traffic through the VPN section
  4. Be aware the instructions for (3) are all iptables which has been superseded, at time of writing, by firewall-cmd. This website explains the firewall-cmd to use
  5. Check that you can connect your iPhone to the VPN. I did this by downloading the free OpenVPN software. I then set up a OpenVPN certificate. You can embed your ca, crt & key files by opening up and embedding the --- BEGIN CERTIFACTE --- ---- END CERTIFICATE --- in < ca > < /ca > < crt >< /crt>< key > < /key > blocks. Note that I had to do this in Mac with text editor, when I used notepad.exe on Win it didn't work. I then emailed this to my iphone and picked installed it.
  6. Check the iPhone connects to VPN and routes it's traffic through (google what's my IP should return the VPN server IP when you run it on iPhone)
  7. Now that you can connect go to your linux server & install wireshark (yum install wireshark)
  8. This installs tshark, which is a command line packet sniffer. Run this in the background with screen tshark -i tun0 -x -w capture.pcap -F pcap (assuming vpn device is tun0)
  9. Now when you want to capture traffic simply start the VPN on your machine
  10. When complete switch off the VPN
  11. Download the .pcap file from your server, and run analysis as you normally would. It's been decrypted on the server when it arrives so the traffic is viewable in plain text (obviously https still encrypted)

Note that the above implementation is not security focussed it's simply about getting a detailed packet capture of all of your iPhone's traffic on 3G/4G/Wireless networks

C# Error "The type initializer for ... threw an exception

If you have web services, check your URL pointing to the service. I had a simular issue which was fixed when I changed my web service URL.

How to get the type of T from a member of a generic class or method?

Type:

type = list.AsEnumerable().SingleOrDefault().GetType();

long long in C/C++

Try:

num3 = 100000000000LL;

And BTW, in C++ this is a compiler extension, the standard does not define long long, thats part of C99.

How to format a number as percentage in R?

I did some benchmarking for speed on these answers and was surprised to see percent in the scales package so touted, given its sluggishness. I imagine the advantage is its automatic detector for for proper formatting, but if you know what your data looks like it seems clear to be avoided.

Here are the results from trying to format a list of 100,000 percentages in (0,1) to a percentage in 2 digits:

library(microbenchmark)
x = runif(1e5)
microbenchmark(times = 100L, andrie1(), andrie2(), richie(), krlmlr())
# Unit: milliseconds
#   expr       min        lq      mean    median        uq       max
# 1 andrie1()  91.08811  95.51952  99.54368  97.39548 102.75665 126.54918 #paste(round())
# 2 andrie2()  43.75678  45.56284  49.20919  47.42042  51.23483  69.10444 #sprintf()
# 3  richie()  79.35606  82.30379  87.29905  84.47743  90.38425 112.22889 #paste(formatC())
# 4  krlmlr() 243.19699 267.74435 304.16202 280.28878 311.41978 534.55904 #scales::percent()

So sprintf emerges as a clear winner when we want to add a percent sign. On the other hand, if we only want to multiply the number and round (go from proportion to percent without "%", then round() is fastest:

# Unit: milliseconds
#        expr      min        lq      mean    median        uq       max
# 1 andrie1()  4.43576  4.514349  4.583014  4.547911  4.640199  4.939159 # round()
# 2 andrie2() 42.26545 42.462963 43.229595 42.960719 43.642912 47.344517 # sprintf()
# 3  richie() 64.99420 65.872592 67.480730 66.731730 67.950658 96.722691 # formatC()

Where can I view Tomcat log files in Eclipse?

@royalsampler said:

Go to the Servers view in Eclipse then right click on the server and click Open. The log files are stored in a folder realative to the path in the "Server path" field.

Since the path field is uneditable, you can also "Open Launch Configuration", click Arguments tab, copy the VM argument for catalina.base (within quotes). This is the full path of your WTP webapp directory. Copying the value to the clipboard can save you the laborious task of browsing the file system to the path.

Also note you should be seeing the output to the log file in your Console view as you run or debug.

Determining the path that a yum package installed to

yum uses RPM, so the following command will list the contents of the installed package:

$ rpm -ql package-name

make iframe height dynamic based on content inside- JQUERY/Javascript

This one is useful when you require a solution with no jquery. In that case you should try adding a container and set a padding to it in percentages

HTML example code:

<div class="iframecontainer">
    <iframe scrolling="no" src="..." class="iframeclass"width="999px" height="618px"></iframe>
</div>

CSS example code:

.iframeclass{
    position: absolute;
    top: 0;
    width: 100%;
}

.iframecontainer{
    position: relative;
    width: 100%;
    height: auto;
    padding-top: 61%;
}

How to clear a textbox once a button is clicked in WPF?

You can use Any of the statement given below to clear the text of the text box on button click:

  1. textBoxName.Text = string.Empty;
  2. textBoxName.Clear();
  3. textBoxName.Text = "";

How to check if a URL exists or returns 404 with Java?

You may want to add

HttpURLConnection.setFollowRedirects(false);
// note : or
//        huc.setInstanceFollowRedirects(false)

if you don't want to follow redirection (3XX)

Instead of doing a "GET", a "HEAD" is all you need.

huc.setRequestMethod("HEAD");
return (huc.getResponseCode() == HttpURLConnection.HTTP_OK);

Parser Error Message: Could not load type 'TestMvcApplication.MvcApplication'

For me, I had a DLL included with my project that had to be run in a 32-bit environment.

The server was configured to run the website in 32-bit mode, but I was not able to run the application on my 64-bit machine because the localhost folder had not been specified to run in 32-bit mode.

Searching a list of objects in Python

filter(lambda x: x.n == 5, myList)

Open another page in php

<?php
    header("Location: index.html");
?>

Just make sure nothing is actually written to the page prior to this code, or it won't work.

Disable Scrolling on Body

This post was helpful, but just wanted to share a slight alternative that may help others:

Setting max-height instead of height also does the trick. In my case, I'm disabling scrolling based on a class toggle. Setting .someContainer {height: 100%; overflow: hidden;} when the container's height is smaller than that of the viewport would stretch the container, which wouldn't be what you'd want. Setting max-height accounts for this, but if the container's height is greater than the viewport's when the content changes, still disables scrolling.

Difference between map and collect in Ruby?

Ruby aliases the method Array#map to Array#collect; they can be used interchangeably. (Ruby Monk)

In other words, same source code :

               static VALUE
rb_ary_collect(VALUE ary)
{
long i;
VALUE collect;

RETURN_SIZED_ENUMERATOR(ary, 0, 0, ary_enum_length);
collect = rb_ary_new2(RARRAY_LEN(ary));
for (i = 0; i < RARRAY_LEN(ary); i++) {
    rb_ary_push(collect, rb_yield(RARRAY_AREF(ary, i)));
}
return collect;
}

http://ruby-doc.org/core-2.2.0/Array.html#method-i-map

Homebrew install specific version of formula?

it could be done very easy for last version of brew.

brew tap homebrew/versions
brew install subversion17 # for svn 1.7 branch instead of last available
brew install postgresql8  # for postgresql 8 (which you ask)

How do I convert a number to a letter in Java?

public static String abcBase36(int i) {
    char[] ALPHABET = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
    int quot = i / 36;
    int rem = i % 36;

    char letter = ALPHABET[rem];
    if (quot == 0) {
        return "" + letter;
    } else {
        return abcBase36(quot - 1) + letter;
    }
}

How do you set autocommit in an SQL Server session?

Autocommit is SQL Server's default transaction management mode. (SQL 2000 onwards)

Ref: Autocommit Transactions

Filter df when values matches part of a string in pyspark

When filtering a DataFrame with string values, I find that the pyspark.sql.functions lower and upper come in handy, if your data could have column entries like "foo" and "Foo":

import pyspark.sql.functions as sql_fun
result = source_df.filter(sql_fun.lower(source_df.col_name).contains("foo"))

jQuery 'input' event

jQuery has the following signature for the .on() method: .on( events [, selector ] [, data ], handler )

Events could be anyone of the ones listed on this reference:

https://developer.mozilla.org/en-US/docs/Web/Events

Though, they are not all supported by every browser.

Mozilla states the following about the input event:

The DOM input event is fired synchronously when the value of an or element is changed. Additionally, it fires on contenteditable editors when its contents are changed.

How do you stretch an image to fill a <div> while keeping the image's aspect-ratio?

Many of the solutions found here have some limitation: some not working in IE ( object-fit) or older browsers, other solutions do not scale up the images (only shrink it), many solution do not support resize of the window and many are not generic, either expect fix resolution or layout(portrait or landscape)

If using javascript and jquery is not a problem I have this solution based on the code of @Tatu Ulmanen. I fixed some issues, and added some code in case the image is loaded dinamically and not available at begining. Basically the idea is to have two different css rules and apply them when required: one when the limitation is the height, so we need to show black bars at the sides, and othe css rule when the limitation is the width, so we need to show black bars at the top/bottom.

function applyResizeCSS(){
    var $i = $('img#imageToResize');
    var $c = $i.parent();
    var i_ar = Oriwidth / Oriheight, c_ar = $c.width() / $c.height();  
    if(i_ar > c_ar){
        $i.css( "width","100%");
        $i.css( "height","auto");          
    }else{
        $i.css( "height","100%");
        $i.css( "width","auto");
    }
}   
var Oriwidth,Oriheight;
$(function() {
    $(window).resize(function() {
        applyResizeCSS();
    });

    $("#slide").load(function(){
        Oriwidth  = this.width,
        Oriheight = this.height; 
        applyResizeCSS();
    }); 

    $(window).resize();
}); 

For an HTML element like:

<img src="images/loading.gif" name="imageToResize" id="imageToResize"/> 

Find duplicates and delete all in notepad++

You could use

Click TextFX ? Click TextFX Tools ? Click Sort lines case insensitive (at column) Duplicates and blank lines have been removed and the data has been sorted alphabetically.

as indicated above. However, the way I did it because I need to replace the duplicates by blank lines and not just remove the lines, once sorted alphabetically:

REPLACE:
((^.*$)(\n))(?=\k<1>)

by

$3

This will convert:

Shorts
Shorts
Shorts
Shorts
Shorts
Shorts Two Pack
Shorts Two Pack
Signature Braces
Signature Braces
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers
Signature Cotton Trousers

to:

Shorts

Shorts Two Pack

Signature Braces










Signature Cotton Trousers

That's how I did it because I specifically needed those lines.

Why is the time complexity of both DFS and BFS O( V + E )

Your sum

v1 + (incident edges) + v2 + (incident edges) + .... + vn + (incident edges)

can be rewritten as

(v1 + v2 + ... + vn) + [(incident_edges v1) + (incident_edges v2) + ... + (incident_edges vn)]

and the first group is O(N) while the other is O(E).

Change font size of UISegmentedControl

In swift 5,

let font = UIFont.systemFont(ofSize: 16)
UISegmentedControl.appearance().setTitleTextAttributes([NSAttributedString.Key.font: font], for: .normal)

jQuery: Count number of list elements?

var listItems = $("#myList").children();

var count = listItems.length;

Of course you can condense this with

var count = $("#myList").children().length;

For more help with jQuery, http://docs.jquery.com/Main_Page is a good place to start.

How can one run multiple versions of PHP 5.x on a development LAMP server?

One way to do this is to have your main version of php set up with mod_php and run all of the others through fast cgi on different ports (i.e. 81, 82, 83 etc). This won't guarantee totally consistent behavior though.

SSL "Peer Not Authenticated" error with HttpClient 4.1

Im not a java developer but was using a java app to test a RESTful API. In order for me to fix the error I had to install the intermediate certificates in the webserver in order to make the error go away. I was using lighttpd, the original certificate was installed on an IIS server. Hope it helps. These were the certificates I had missing on the server.

  • CA.crt
  • UTNAddTrustServer_CA.crt
  • AddTrustExternalCARoot.crt

use "netsh wlan set hostednetwork ..." to create a wifi hotspot and the authentication can't work correctly

Use these commands on a windows command prompt(cmd) with administrator privilege (run as administrator):

netsh wlan set hostednetwork mode=allow ssid=tests key=tests123

netsh wlan start hostednetwork

Then you go to Network and sharing center and click on "change adapter settings" (I'm using windows 7, it can be a little different on windows 8)

Then right click on the lan connection (internet connection that you are using), properties.

Click on sharing tab, select the wireless connection tests (the name tests you can change on the command line) and check "Allow other network users to connect through this network connection"

This done, your connection is ready to use!

Correct way to remove plugin from Eclipse

Using the menus, open

  • Help | About Eclipse IDE | Installation details (in newer versions),
  • Help | Installation Details (in older versions), or
  • Help | About Eclipse | Installation details (in even older versions).

In the "Installed software" tab click on the software that you wish to uninstall, then click the "Uninstall..." button below.

If you installed the plug-in by dropping into the dropins folder, then just delete it from the dropins folder and restart Eclipse.

See the answer of @Cogentleman for more recent versions of Eclipse.

Sending an HTTP POST request on iOS

Objective C

Post API with parameters and validate with url to navigate if json
response key with status:"success"

NSString *string= [NSString stringWithFormat:@"url?uname=%@&pass=%@&uname_submit=Login",self.txtUsername.text,self.txtPassword.text];
    NSLog(@"%@",string);
    NSURL *url = [NSURL URLWithString:string];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    [request setHTTPMethod:@"POST"];
    NSURLResponse *response;
    NSError *err;
    NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&err];
    NSLog(@"responseData: %@", responseData);
    NSString *str = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
    NSLog(@"responseData: %@", str);
        NSDictionary* json = [NSJSONSerialization JSONObjectWithData:responseData
                                                         options:kNilOptions
                                                           error:nil];
    NSDictionary* latestLoans = [json objectForKey:@"status"];
    NSString *str2=[NSString stringWithFormat:@"%@", latestLoans];
    NSString *str3=@"success";
    if ([str3 isEqualToString:str2 ])
    {
        [self performSegueWithIdentifier:@"move" sender:nil];
        NSLog(@"successfully.");
    }
    else
    {
        UIAlertController *alert= [UIAlertController
                                 alertControllerWithTitle:@"Try Again"
                                 message:@"Username or Password is Incorrect."
                                 preferredStyle:UIAlertControllerStyleAlert];
        UIAlertAction* ok = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                   handler:^(UIAlertAction * action){
                                                       [self.view endEditing:YES];
                                                   }
                             ];
        [alert addAction:ok];
        [[UIView appearanceWhenContainedIn:[UIAlertController class], nil] setTintColor:[UIColor redColor]];
        [self presentViewController:alert animated:YES completion:nil];
        [self.view endEditing:YES];
      }

JSON Response : {"status":"success","user_id":"58","user_name":"dilip","result":"You have been logged in successfully"} Working code

**

Generate insert script for selected records?

You could create a view with your criteria and then export the view?

How to quickly form groups (quartiles, deciles, etc) by ordering column(s) in a data frame

I'll add the data.table version for anyone else Googling it (i.e., @BondedDust's solution translated to data.table and pared down a tad):

library(data.table)
setDT(temp)
temp[ , quartile := cut(value,
                        breaks = quantile(value, probs = 0:4/4),
                        labels = 1:4, right = FALSE)]

Which is much better (cleaner, faster) than what I had been doing:

temp[ , quartile := 
        as.factor(ifelse(value < quantile(value, .25), 1,
                         ifelse(value < quantile(value, .5), 2,
                                ifelse(value < quantile(value, .75), 3, 4))]

Note, however, that this approach requires the quantiles to be distinct, e.g. it will fail on rep(0:1, c(100, 1)); what to do in this case is open ended so I leave it up to you.

NoClassDefFoundError in Java: com/google/common/base/Function

I wanted to try a simple class outside IDE and stuff. So downloaded selenium zip from website and run the class like this:

java -cp selenium-2.50.1/*:selenium-2.50.1/libs/*:. my/package/MyClass <params>

I had the issue that I initially used lib instead of libs. I didn't need to add selenium standalone jar. This is Java 8 that understands wildcards in classpath. I think java 7 would also do.

Return a 2d array from a function

The function returns a static 2D array

const int N = 6;
int (*(MakeGridOfCounts)())[N] {
 static int cGrid[N][N] = {{0, }, {0, }, {0, }, {0, }, {0, }, {0, }};
 return cGrid;
}

int main() {
int (*arr)[N];
arr = MakeGridOfCounts();
}

You need to make the array static since it will be having a block scope, when the function call ends, the array will be created and destroyed. Static scope variables last till the end of program.

How to format a number 0..9 to display with 2 digits (it's NOT a date)

The String class comes with the format abilities:

System.out.println(String.format("%02d", 5));

for full documentation, here is the doc

Get all column names of a DataTable into string array using (LINQ/Predicate)

List<String> lsColumns = new List<string>();

if(dt.Rows.Count>0)
{
    var count = dt.Rows[0].Table.Columns.Count;

    for (int i = 0; i < count;i++ )
    {
        lsColumns.Add(Convert.ToString(dt.Rows[0][i]));
    }
}

sweet-alert display HTML code in text

Use SweetAlert's html setting.

You can set output html direct to this option:

var hh = "<b>test</b>";
swal({
    title: "" + txt + "", 
    html: "Testno  sporocilo za objekt " + hh + "",  
    confirmButtonText: "V redu", 
    allowOutsideClick: "true" 
});

Or

swal({
    title: "" + txt + "", 
    html: "Testno  sporocilo za objekt <b>teste</b>",  
    confirmButtonText: "V redu", 
    allowOutsideClick: "true" 
});

Can you nest html forms?

Even if you could get it to work in one browser, there's no guarantee that it would work the same in all browsers. So while you might be able to get it to work some of the time, you certainly wouldn't be able to get it to work all of the time.

How do I apply a perspective transform to a UIView?

Swift 5.0

func makeTransform(horizontalDegree: CGFloat, verticalDegree: CGFloat, maxVertical: CGFloat,rotateDegree: CGFloat, maxHorizontal: CGFloat) -> CATransform3D {
    var transform = CATransform3DIdentity
           
    transform.m34 = 1 / -500
    
    let xAnchor = (horizontalDegree / (2 * maxHorizontal)) + 0.5
    let yAnchor = (verticalDegree / (-2 * maxVertical)) + 0.5
    let anchor = CGPoint(x: xAnchor, y: yAnchor)
    
    setAnchorPoint(anchorPoint: anchor, forView: self.imgView)
    let hDegree  = (CGFloat(horizontalDegree) * .pi)  / 180
    let vDegree  = (CGFloat(verticalDegree) * .pi)  / 180
    let rDegree  = (CGFloat(rotateDegree) * .pi)  / 180
    transform = CATransform3DRotate(transform, vDegree , 1, 0, 0)
    transform = CATransform3DRotate(transform, hDegree , 0, 1, 0)
    transform = CATransform3DRotate(transform, rDegree , 0, 0, 1)
    
    return transform
}

func setAnchorPoint(anchorPoint: CGPoint, forView view: UIView) {
    var newPoint = CGPoint(x: view.bounds.size.width * anchorPoint.x, y: view.bounds.size.height * anchorPoint.y)
    var oldPoint = CGPoint(x: view.bounds.size.width * view.layer.anchorPoint.x, y: view.bounds.size.height * view.layer.anchorPoint.y)
    
    newPoint = newPoint.applying(view.transform)
    oldPoint = oldPoint.applying(view.transform)
    
    var position = view.layer.position
    position.x -= oldPoint.x
    position.x += newPoint.x
    
    position.y -= oldPoint.y
    position.y += newPoint.y
    
    print("Anchor: \(anchorPoint)")
    
    view.layer.position = position
    view.layer.anchorPoint = anchorPoint
}

you only need to call the function with your degree. for example:

var transform = makeTransform(horizontalDegree: 20.0 , verticalDegree: 25.0, maxVertical: 25, rotateDegree: 20, maxHorizontal: 25)
imgView.layer.transform = transform

Efficiently checking if arbitrary object is NaN in Python / numpy / pandas?

I found this brilliant solution here, it uses the simple logic NAN!=NAN. https://www.codespeedy.com/check-if-a-given-string-is-nan-in-python/

Using above example you can simply do the following. This should work on different type of objects as it simply utilize the fact that NAN is not equal to NAN.

 import numpy as np
 s = pd.Series(['apple', np.nan, 'banana'])
 s.apply(lambda x: x!=x)
 out[252]
 0    False
 1     True
 2    False
 dtype: bool

Rebase array keys after unsetting elements

Or you can make your own function that passes the array by reference.

function array_unset($unsets, &$array) {
  foreach ($array as $key => $value) {
    foreach ($unsets as $unset) {
      if ($value == $unset) {
        unset($array[$key]);
        break;
      }
    }
  }
  $array = array_values($array);
}

So then all you have to do is...

$unsets = array(1,2);
array_unset($unsets, $array);

... and now your $array is without the values you placed in $unsets and the keys are reset

jQuery: Adding two attributes via the .attr(); method

Should work:

.attr({
    target:"nw", 
    title:"Opens in a new window",
    "data-value":"internal link" // attributes which contain dash(-) should be covered in quotes.
});

Note:

" When setting multiple attributes, the quotes around attribute names are optional.

WARNING: When setting the 'class' attribute, you must always use quotes!

From the jQuery documentation (Sep 2016) for .attr:

Attempting to change the type attribute on an input or button element created via document.createElement() will throw an exception on Internet Explorer 8 or older.

Edit:
For future reference... To get a single attribute you would use

var strAttribute = $(".something").attr("title");

To set a single attribute you would use

$(".something").attr("title","Test");

To set multiple attributes you need to wrap everything in { ... }

$(".something").attr( { title:"Test", alt:"Test2" } );

Edit - If you're trying to get/set the 'checked' attribute from a checkbox...

You will need to use prop() as of jQuery 1.6+

the .prop() method provides a way to explicitly retrieve property values, while .attr() retrieves attributes.

...the most important concept to remember about the checked attribute is that it does not correspond to the checked property. The attribute actually corresponds to the defaultChecked property and should be used only to set the initial value of the checkbox. The checked attribute value does not change with the state of the checkbox, while the checked property does

So to get the checked status of a checkbox, you should use:

$('#checkbox1').prop('checked'); // Returns true/false

Or to set the checkbox as checked or unchecked you should use:

$('#checkbox1').prop('checked', true); // To check it
$('#checkbox1').prop('checked', false); // To uncheck it

Git commit -a "untracked files"?

Make sure you're in the right directory (repository main folder) in your local git so it can find .git folder configuration before you commit or add files.

Is there an easy way to add a border to the top and bottom of an Android View?

Here is a way to achieve it.

    <?xml version="1.0" encoding="utf-8"?>
    <layer-list xmlns:android="http://schemas.android.com/apk/res/android">
        <item>
            <shape android:shape="rectangle">
                <stroke
                    android:width="1dp"
                    android:color="@color/grey_coaching_text" />
            </shape>
        </item>

        <item
            android:bottom="1dp"
            android:top="1dp">
            <shape android:shape="rectangle">
                <solid android:color="@color/white" />
            </shape>
        </item>
    </layer-list>

First item for stroke and second one for solid background. Hiding left and right borders.

Get 2 Digit Number For The Month

For me the quickest solution was

DATE_FORMAT(CURDATE(),'%m')

printf() prints whole array

But still, the memory address for each letter in this address is different.

Memory address is different but as its array of characters they are sequential. When you pass address of first element and use %s, printf will print all characters starting from given address until it finds '\0'.

How to reshape data from long to wide format

much easier way!

devtools::install_github("yikeshu0611/onetree") #install onetree package

library(onetree)
widedata=reshape_toWide(data = dat1,id = "name",j = "numbers",value.var.prefix = "value")
widedata

        name     value1     value2     value3     value4
   firstName  0.3407997 -0.7033403 -0.3795377 -0.7460474
  secondName -0.8981073 -0.3347941 -0.5013782 -0.1745357

if you want to go back from wide to long, only change Wide to Long, and no changes in objects.

reshape_toLong(data = widedata,id = "name",j = "numbers",value.var.prefix = "value")

        name numbers      value
   firstName       1  0.3407997
  secondName       1 -0.8981073
   firstName       2 -0.7033403
  secondName       2 -0.3347941
   firstName       3 -0.3795377
  secondName       3 -0.5013782
   firstName       4 -0.7460474
  secondName       4 -0.1745357

How to do the equivalent of pass by reference for primitives in Java

Java is not call by reference it is call by value only

But all variables of object type are actually pointers.

So if you use a Mutable Object you will see the behavior you want

public class XYZ {

    public static void main(String[] arg) {
        StringBuilder toyNumber = new StringBuilder("5");
        play(toyNumber);
        System.out.println("Toy number in main " + toyNumber);
    }

    private static void play(StringBuilder toyNumber) {
        System.out.println("Toy number in play " + toyNumber);
        toyNumber.append(" + 1");
        System.out.println("Toy number in play after increement " + toyNumber);
    }
}

Output of this code:

run:
Toy number in play 5
Toy number in play after increement 5 + 1
Toy number in main 5 + 1
BUILD SUCCESSFUL (total time: 0 seconds)

You can see this behavior in Standard libraries too. For example Collections.sort(); Collections.shuffle(); These methods does not return a new list but modifies it's argument object.

    List<Integer> mutableList = new ArrayList<Integer>();

    mutableList.add(1);
    mutableList.add(2);
    mutableList.add(3);
    mutableList.add(4);
    mutableList.add(5);

    System.out.println(mutableList);

    Collections.shuffle(mutableList);

    System.out.println(mutableList);

    Collections.sort(mutableList);

    System.out.println(mutableList);

Output of this code:

run:
[1, 2, 3, 4, 5]
[3, 4, 1, 5, 2]
[1, 2, 3, 4, 5]
BUILD SUCCESSFUL (total time: 0 seconds)

Hibernate, @SequenceGenerator and allocationSize

After digging into hibernate source code and Below configuration goes to Oracle db for the next value after 50 inserts. So make your INST_PK_SEQ increment 50 each time it is called.

Hibernate 5 is used for below strategy

Check also below http://docs.jboss.org/hibernate/orm/5.1/userguide/html_single/Hibernate_User_Guide.html#identifiers-generators-sequence

@Id
@Column(name = "ID")
@GenericGenerator(name = "INST_PK_SEQ", 
strategy = "org.hibernate.id.enhanced.SequenceStyleGenerator",
parameters = {
        @org.hibernate.annotations.Parameter(
                name = "optimizer", value = "pooled-lo"),
        @org.hibernate.annotations.Parameter(
                name = "initial_value", value = "1"),
        @org.hibernate.annotations.Parameter(
                name = "increment_size", value = "50"),
        @org.hibernate.annotations.Parameter(
                name = SequenceStyleGenerator.SEQUENCE_PARAM, value = "INST_PK_SEQ"),
    }
)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "INST_PK_SEQ")
private Long id;

Jenkins Host key verification failed

Try

ssh-keygen -R hostname

-R hostname Removes all keys belonging to hostname from a known_hosts file. This option is useful to delete hashed hosts

What is the Eclipse shortcut for "public static void main(String args[])"?

To get public static void main(String[] args) line in eclipse without typing the whole line type "main" and press Ctrl + space then, you will get the option for the main method select it.

enter image description here

Error when deploying an artifact in Nexus

I had this exact problem today and the problem was that the version I was trying to release:perform was already in the Nexus repo.

In my case this was likely due to a network disconnect during an earlier invocation of release:perform. Even though I lost my connection, it appears the release succeeded.

Sync data between Android App and webserver

If you write this yourself these are some of the points to keep in mind

Proper authentication between the device and the Sync Server

A sync protocol between the device and the server. It will usually go in 3 phases, authentication, data exchange, status exchange (which operations worked and which failed)

Pick your payload format. I suggest SyncML based XML mixed with JSON based format to represent the actual data. So SyncML for the protocol, and JSON for the actual data being exchanged. Using JSON Array while manipulating the data is always preferred as it is easy to access data using JSON Array.

Keeping track of data changes on both client and server. You can maintain a changelog of ids that change and pick them up during a sync session. Also, clear the changelog as the objects are successfully synchronized. You can also use a boolean variable to confirm the synchronization status, i.e. last time of sync. It will be helpful for end users to identify the time when last sync is done.

Need to have a way to communicate from the server to the device to start a sync session as data changes on the server. You can use C2DM or write your own persistent tcp based communication. The tcp approach is a lot seamless

A way to replicate data changes across multiple devices

And last but not the least, a way to detect and handle conflicts

Hope this helps as a good starting point.

installing cPickle with python 3.5

cPickle comes with the standard library… in python 2.x. You are on python 3.x, so if you want cPickle, you can do this:

>>> import _pickle as cPickle

However, in 3.x, it's easier just to use pickle.

No need to install anything. If something requires cPickle in python 3.x, then that's probably a bug.

Setting value of active workbook in Excel VBA

Try this.

Dim Workbk as workbook
Set Workbk = thisworkbook

Now everything you program will apply just for your containing macro workbook.

Select all child elements recursively in CSS

The rule is as following :

A B 

B as a descendant of A

A > B 

B as a child of A

So

div.dropdown *

and not

div.dropdown > *

How do I change the select box arrow

You can skip the container or background image with pure css arrow:

select {

  /* make arrow and background */

  background:
    linear-gradient(45deg, transparent 50%, blue 50%),
    linear-gradient(135deg, blue 50%, transparent 50%),
    linear-gradient(to right, skyblue, skyblue);
  background-position:
    calc(100% - 21px) calc(1em + 2px),
    calc(100% - 16px) calc(1em + 2px),
    100% 0;
  background-size:
    5px 5px,
    5px 5px,
    2.5em 2.5em;
  background-repeat: no-repeat;

  /* styling and reset */

  border: thin solid blue;
  font: 300 1em/100% "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5em;
  padding: 0.5em 3.5em 0.5em 1em;

  /* reset */

  border-radius: 0;
  margin: 0;      
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  -webkit-appearance:none;
  -moz-appearance:none;
}

Sample here

Postgresql: error "must be owner of relation" when changing a owner object

From the fine manual.

You must own the table to use ALTER TABLE.

Or be a database superuser.

ERROR: must be owner of relation contact

PostgreSQL error messages are usually spot on. This one is spot on.

How to use regex in file find

Use -regex not -name, and be aware that the regex matches against what find would print, e.g. "/home/test/test.log" not "test.log"

How to delete large data of table in SQL without log?

You can also use GO + how many times you want to execute the same query.

DELETE TOP (10000)  [TARGETDATABASE].[SCHEMA].[TARGETTABLE] 
WHERE readTime < dateadd(MONTH,-1,GETDATE());
-- how many times you want the query to repeat
GO 100

How can I send an email by Java application using GMail, Yahoo, or Hotmail?

Value added:

  • encoding pitfalls in subject, message and display name
  • only one magic property is needed for modern java mail library versions
  • Session.getInstance() recommended over Session.getDefaultInstance()
  • attachment in the same example
  • still works after Google turns off less secure apps: Enable 2-factor authentication in your organization -> turn on 2FA -> generate app password.
    import java.io.File;
    import java.nio.charset.StandardCharsets;
    import java.util.Properties;
    import java.util.logging.Level;
    import java.util.logging.Logger;
    import javax.activation.DataHandler;
    import javax.mail.Message;
    import javax.mail.Session;
    import javax.mail.Transport;
    import javax.mail.internet.InternetAddress;
    import javax.mail.internet.MimeBodyPart;
    import javax.mail.internet.MimeMessage;
    import javax.mail.internet.MimeMultipart;
    import javax.mail.util.ByteArrayDataSource;
    
    public class Gmailer {
      private static final Logger LOGGER = Logger.getLogger(Gmailer.class.getName());
    
      public static void main(String[] args) {
        send();
      }
    
      public static void send() {
        Transport transport = null;
        try {
          String accountEmail = "[email protected]";
          String accountAppPassword = "";
          String displayName = "Display-Name ?";
          String replyTo = "[email protected]";
    
          String to = "[email protected]";
          String cc = "[email protected]";
          String bcc = "[email protected]";
    
          String subject = "Subject ?";
          String message = "<span style='color: red;'>?</span>";
          String type = "html"; // or "plain"
          String mimeTypeWithEncoding = "text/" + type + "; charset=" + StandardCharsets.UTF_8.name();
    
          File attachmentFile = new File("Attachment.pdf");
          // https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types
          String attachmentMimeType = "application/pdf";
          byte[] bytes = ...; // read file to byte array
    
          Properties properties = System.getProperties();
          properties.put("mail.debug", "true");
          // i found that this is the only property necessary for a modern java mail version
          properties.put("mail.smtp.starttls.enable", "true");
          // https://javaee.github.io/javamail/FAQ#getdefaultinstance
          Session session = Session.getInstance(properties);
    
          MimeMessage mimeMessage = new MimeMessage(session);
    
          // probably best to use the account email address, to avoid landing in spam or blacklists
          // not even sure if the server would accept a differing from address
          InternetAddress from = new InternetAddress(accountEmail);
          from.setPersonal(displayName, StandardCharsets.UTF_8.name());
          mimeMessage.setFrom(from);
    
          mimeMessage.setReplyTo(InternetAddress.parse(replyTo));
    
          mimeMessage.setRecipients(Message.RecipientType.TO, InternetAddress.parse(to));
          mimeMessage.setRecipients(Message.RecipientType.CC, InternetAddress.parse(cc));
          mimeMessage.setRecipients(Message.RecipientType.BCC, InternetAddress.parse(bcc));
    
          mimeMessage.setSubject(subject, StandardCharsets.UTF_8.name());
    
          MimeMultipart multipart = new MimeMultipart();
    
          MimeBodyPart messagePart = new MimeBodyPart();
          messagePart.setContent(mimeMessage, mimeTypeWithEncoding);
          multipart.addBodyPart(messagePart);
    
          MimeBodyPart attachmentPart = new MimeBodyPart();
          attachmentPart.setDataHandler(new DataHandler(new ByteArrayDataSource(bytes, attachmentMimeType)));
          attachmentPart.setFileName(attachmentFile.getName());
          multipart.addBodyPart(attachmentPart);
    
          mimeMessage.setContent(multipart);
    
          transport = session.getTransport();
          transport.connect("smtp.gmail.com", 587, accountEmail, accountAppPassword);
          transport.sendMessage(mimeMessage, mimeMessage.getAllRecipients());
        }
        catch(Exception e) {
          // I prefer to bubble up exceptions, so the caller has the info that someting went wrong, and gets a chance to handle it.
          // I also prefer not to force the exception in the signature.
          throw e instanceof RuntimeException ? (RuntimeException) e : new RuntimeException(e);
        }
        finally {
          if(transport != null) {
            try {
              transport.close();
            }
            catch(Exception e) {
              LOGGER.log(Level.WARNING, "failed to close java mail transport: " + e);
            }
          }
        }
      }
    }

using javascript to detect whether the url exists before display in iframe

You could test the url via AJAX and read the status code - that is if the URL is in the same domain.

If it's a remote domain, you could have a server script on your own domain check out a remote URL.

Proper way to exit iPhone application?

This has gotten a good answer but decided to expand a bit:

You can't get your application accepted to AppStore without reading Apple's iOS Human Interface Guidelines well. (they retain the right to reject you for doing anything against them) The section "Don't Quit Programmatically" http://developer.apple.com/library/ios/#DOCUMENTATION/UserExperience/Conceptual/MobileHIG/UEBestPractices/UEBestPractices.html is an exact guideline in how you should treat in this case.

If you ever have a problem with Apple platform you can't easily find a solution for, consult HIG. It's possible Apple simply doesn't want you to do it and they usually (I'm not Apple so I can't guarantee always) do say so in their documentation.

Is there a way to programmatically scroll a scroll view to a specific edit text?

My EditText was nested several layers inside my ScrollView, which itself isn't the layout's root view. Because getTop() and getBottom() were seeming to report the coordinates within it's containing view, I had it compute the distance from the top of the ScrollView to the top of the EditText by iterating through the parents of the EditText.

// Scroll the view so that the touched editText is near the top of the scroll view
new Thread(new Runnable()
{
    @Override
    public
    void run ()
    {
        // Make it feel like a two step process
        Utils.sleep(333);

        // Determine where to set the scroll-to to by measuring the distance from the top of the scroll view
        // to the control to focus on by summing the "top" position of each view in the hierarchy.
        int yDistanceToControlsView = 0;
        View parentView = (View) m_editTextControl.getParent();
        while (true)
        {
            if (parentView.equals(scrollView))
            {
                break;
            }
            yDistanceToControlsView += parentView.getTop();
            parentView = (View) parentView.getParent();
        }

        // Compute the final position value for the top and bottom of the control in the scroll view.
        final int topInScrollView = yDistanceToControlsView + m_editTextControl.getTop();
        final int bottomInScrollView = yDistanceToControlsView + m_editTextControl.getBottom();

        // Post the scroll action to happen on the scrollView with the UI thread.
        scrollView.post(new Runnable()
        {
            @Override
            public void run()
            {
                int height =m_editTextControl.getHeight();
                scrollView.smoothScrollTo(0, ((topInScrollView + bottomInScrollView) / 2) - height);
                m_editTextControl.requestFocus();
            }
        });
    }
}).start();

Converting String to "Character" array in Java

Converting String to Character Array and then Converting Character array back to String

   //Givent String
   String given = "asdcbsdcagfsdbgdfanfghbsfdab";

   //Converting String to Character Array(It's an inbuild method of a String)
   char[] characterArray = given.toCharArray();
   //returns = [a, s, d, c, b, s, d, c, a, g, f, s, d, b, g, d, f, a, n, f, g, h, b, s, f, d, a, b]

//ONE WAY : Converting back Character array to String

  int length = Arrays.toString(characterArray).replaceAll("[, ]","").length();

  //First Way to get the string back
  Arrays.toString(characterArray).replaceAll("[, ]","").substring(1,length-1)
  //returns asdcbsdcagfsdbgdfanfghbsfdab
  or 
  // Second way to get the string back
  Arrays.toString(characterArray).replaceAll("[, ]","").replace("[","").replace("]",""))
 //returns asdcbsdcagfsdbgdfanfghbsfdab

//Second WAY : Converting back Character array to String

String.valueOf(characterArray);

//Third WAY : Converting back Character array to String

Arrays.stream(characterArray)
           .mapToObj(i -> (char)i)
           .collect(Collectors.joining());

Converting string to Character Array

Character[] charObjectArray =
                           givenString.chars().
                               mapToObj(c -> (char)c).
                               toArray(Character[]::new);

Converting char array to Character Array

 String givenString = "MyNameIsArpan";
char[] givenchararray = givenString.toCharArray();


     String.valueOf(givenchararray).chars().mapToObj(c -> 
                         (char)c).toArray(Character[]::new);

benefits of Converting char Array to Character Array you can use the Arrays.stream funtion to get the sub array

String subStringFromCharacterArray = 

              Arrays.stream(charObjectArray,2,6).
                          map(String::valueOf).
                          collect(Collectors.joining());

how to get date of yesterday using php?

you can do this by

date("F j, Y", time() - 60 * 60 * 24);

or by

date("F j, Y", strtotime("yesterday"));

How can I create and style a div using JavaScript?

Here's one solution that I'd use:

var div = '<div id="yourId" class="yourClass" yourAttribute="yourAttributeValue">blah</div>';

If you wanted the attribute and/or attribute values to be based on variables:

var id = "hello";
var classAttr = "class";
var div = '<div id='+id+' '+classAttr+'="world" >Blah</div>';

Then, to append to the body:

document.getElementsByTagName("body").innerHTML = div;

Easy as pie.

Problem with SMTP authentication in PHP using PHPMailer, with Pear Mail works

This isn't on the code parter it's on the server side Contact your Server Manager or fix it from server if you own it If you use CPANEL/WHM GO TO WHM/SMTP RESTRICTIONS AND DISABLE IT

how to print a string to console in c++

All you have to do is add:

#include <string>
using namespace std;

at the top. (BTW I know this was posted in 2013 but I just wanted to answer)

malloc an array of struct pointers

I agree with @maverik above, I prefer not to hide the details with a typedef. Especially when you are trying to understand what is going on. I also prefer to see everything instead of a partial code snippet. With that said, here is a malloc and free of a complex structure.

The code uses the ms visual studio leak detector so you can experiment with the potential leaks.

#include "stdafx.h"

#include <string.h>
#include "msc-lzw.h"

#define _CRTDBG_MAP_ALLOC
#include <stdlib.h>
#include <crtdbg.h> 



// 32-bit version
int hash_fun(unsigned int key, int try_num, int max) {
    return (key + try_num) % max;  // the hash fun returns a number bounded by the number of slots.
}


// this hash table has
// key is int
// value is char buffer
struct key_value_pair {
    int key; // use this field as the key
    char *pValue;  // use this field to store a variable length string
};


struct hash_table {
    int max;
    int number_of_elements;
    struct key_value_pair **elements;  // This is an array of pointers to mystruct objects
};


int hash_insert(struct key_value_pair *data, struct hash_table *hash_table) {

    int try_num, hash;
    int max_number_of_retries = hash_table->max;


    if (hash_table->number_of_elements >= hash_table->max) {
        return 0; // FULL
    }

    for (try_num = 0; try_num < max_number_of_retries; try_num++) {

        hash = hash_fun(data->key, try_num, hash_table->max);

        if (NULL == hash_table->elements[hash]) { // an unallocated slot
            hash_table->elements[hash] = data;
            hash_table->number_of_elements++;
            return RC_OK;
        }
    }
    return RC_ERROR;
}


// returns the corresponding key value pair struct
// If a value is not found, it returns null
//
// 32-bit version
struct key_value_pair *hash_retrieve(unsigned int key, struct hash_table *hash_table) {

    unsigned int try_num, hash;
    unsigned int max_number_of_retries = hash_table->max;

    for (try_num = 0; try_num < max_number_of_retries; try_num++) {

        hash = hash_fun(key, try_num, hash_table->max);

        if (hash_table->elements[hash] == 0) {
            return NULL; // Nothing found
        }

        if (hash_table->elements[hash]->key == key) {
            return hash_table->elements[hash];
        }
    }
    return NULL;
}


// Returns the number of keys in the dictionary
// The list of keys in the dictionary is returned as a parameter.  It will need to be freed afterwards
int keys(struct hash_table *pHashTable, int **ppKeys) {

    int num_keys = 0;

    *ppKeys = (int *) malloc( pHashTable->number_of_elements * sizeof(int) );

    for (int i = 0; i < pHashTable->max; i++) {
        if (NULL != pHashTable->elements[i]) {
            (*ppKeys)[num_keys] = pHashTable->elements[i]->key;
            num_keys++;
        }
    }
    return num_keys;
}

// The dictionary will need to be freed afterwards
int allocate_the_dictionary(struct hash_table *pHashTable) {


    // Allocate the hash table slots
    pHashTable->elements = (struct key_value_pair **) malloc(pHashTable->max * sizeof(struct key_value_pair));  // allocate max number of key_value_pair entries
    for (int i = 0; i < pHashTable->max; i++) {
        pHashTable->elements[i] = NULL;
    }



    // alloc all the slots
    //struct key_value_pair *pa_slot;
    //for (int i = 0; i < pHashTable->max; i++) {
    //  // all that he could see was babylon
    //  pa_slot = (struct key_value_pair *)  malloc(sizeof(struct key_value_pair));
    //  if (NULL == pa_slot) {
    //      printf("alloc of slot failed\n");
    //      while (1);
    //  }
    //  pHashTable->elements[i] = pa_slot;
    //  pHashTable->elements[i]->key = 0;
    //}

    return RC_OK;
}


// This will make a dictionary entry where
//   o  key is an int
//   o  value is a character buffer
//
// The buffer in the key_value_pair will need to be freed afterwards
int make_dict_entry(int a_key, char * buffer, struct key_value_pair *pMyStruct) {

    // determine the len of the buffer assuming it is a string
    int len = strlen(buffer);

    // alloc the buffer to hold the string
    pMyStruct->pValue = (char *) malloc(len + 1); // add one for the null terminator byte
    if (NULL == pMyStruct->pValue) {
        printf("Failed to allocate the buffer for the dictionary string value.");
        return RC_ERROR;
    }
    strcpy(pMyStruct->pValue, buffer);
    pMyStruct->key = a_key;

    return RC_OK;
}


// Assumes the hash table has already been allocated.
int add_key_val_pair_to_dict(struct hash_table *pHashTable, int key, char *pBuff) {

    int rc;
    struct key_value_pair *pKeyValuePair;

    if (NULL == pHashTable) {
        printf("Hash table is null.\n");
        return RC_ERROR;
    }

    // Allocate the dictionary key value pair struct
    pKeyValuePair = (struct key_value_pair *) malloc(sizeof(struct key_value_pair));
    if (NULL == pKeyValuePair) {
        printf("Failed to allocate key value pair struct.\n");
        return RC_ERROR;
    }


    rc = make_dict_entry(key, pBuff, pKeyValuePair);  // a_hash_table[1221] = "abba"
    if (RC_ERROR == rc) {
        printf("Failed to add buff to key value pair struct.\n");
        return RC_ERROR;
    }


    rc = hash_insert(pKeyValuePair, pHashTable);
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }

    return RC_OK;
}


void dump_hash_table(struct hash_table *pHashTable) {

    // Iterate the dictionary by keys
    char * pValue;
    struct key_value_pair *pMyStruct;
    int *pKeyList;
    int num_keys;

    printf("i\tKey\tValue\n");
    printf("-----------------------------\n");
    num_keys = keys(pHashTable, &pKeyList);
    for (int i = 0; i < num_keys; i++) {
        pMyStruct = hash_retrieve(pKeyList[i], pHashTable);
        pValue = pMyStruct->pValue;
        printf("%d\t%d\t%s\n", i, pKeyList[i], pValue);
    }

    // Free the key list
    free(pKeyList);

}

int main(int argc, char *argv[]) {

    int rc;
    int i;


    struct hash_table a_hash_table;
    a_hash_table.max = 20;   // The dictionary can hold at most 20 entries.
    a_hash_table.number_of_elements = 0;  // The intial dictionary has 0 entries.
    allocate_the_dictionary(&a_hash_table);

    rc = add_key_val_pair_to_dict(&a_hash_table, 1221, "abba");
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }
    rc = add_key_val_pair_to_dict(&a_hash_table, 2211, "bbaa");
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }
    rc = add_key_val_pair_to_dict(&a_hash_table, 1122, "aabb");
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }
    rc = add_key_val_pair_to_dict(&a_hash_table, 2112, "baab");
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }
    rc = add_key_val_pair_to_dict(&a_hash_table, 1212, "abab");
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }
    rc = add_key_val_pair_to_dict(&a_hash_table, 2121, "baba");
    if (RC_ERROR == rc) {
        printf("insert has failed!\n");
        return RC_ERROR;
    }



    // Iterate the dictionary by keys
    dump_hash_table(&a_hash_table);

    // Free the individual slots
    for (i = 0; i < a_hash_table.max; i++) {
        // all that he could see was babylon
        if (NULL != a_hash_table.elements[i]) {
            free(a_hash_table.elements[i]->pValue);  // free the buffer in the struct
            free(a_hash_table.elements[i]);  // free the key_value_pair entry
            a_hash_table.elements[i] = NULL;
        }
    }


    // Free the overall dictionary
    free(a_hash_table.elements);


    _CrtDumpMemoryLeaks();
    return 0;
}

How do I get the type of a variable?

The main difference between C++ and Javascript is that C++ is a static-typed language, wile javascript is dynamic.

In dynamic typed languages a variable can contain whatever thing, and its type is given by the value it holds, moment by moment. In static typed languages the type of a variable is declared, and cannot change.

There can be dynamic dispatch and object composition and subtyping (inheritance and virtual functions) as well as static-dispatch and supertyping (via template CRTP), but in any case the type of the variable must be known to the compiler.

If you are in the position to don't know what it is or could be, it is because you designed something as the language has a dynamic type-system.

If that's the case you had better to re-think your design, since it is going into a land not natural for the language you are using (most like going in a motorway with a caterpillar, or in the water with a car)

How to use bluetooth to connect two iPhone?

If I remember correctly, Bluetooth defines certain roles that devices can take. Most cell phones only support a certain number of roles. For instance, I can have a Bluetooth stereo headset that connects to my phone to receive audio, but just because my cell phone has Bluetooth does mean that it supports BEING a speaker for a different device - it doesn't advertise its capabilities of having a speaker for use by other Bluetooth devices.

I assume you want to transfer files between two iPhones? Transferring files via Bluetooth does seem like functionality that I would put in the iPhone, but I'm not Apple so I don't know for sure. In fact, yes, it seems that file transfer is not supported except in jailbroken phones:

http://gizmodo.com/5138797/iphone-bluetooth-file-transfer-coming-soon-yes

You'll probably get similar answers for Bluetooth Dial-Up Networking. I'd imagine they kept the Bluetooth commands out of the SDK for various reasons and you'll have to jailbreak your phone to get the functionality back.

Reading a single char in Java

.... char ch; ... ch=scan.next().charAt(0); . . It's the easy way to get character.

Usage of the backtick character (`) in JavaScript

ECMAScript 6 comes up with a new type of string literal, using the backtick as the delimiter. These literals do allow basic string interpolation expressions to be embedded, which are then automatically parsed and evaluated.

let person = {name: 'RajiniKanth', age: 68, greeting: 'Thalaivaaaa!' };

let usualHtmlStr = "<p>My name is " + person.name + ",</p>\n" +
  "<p>I am " + person.age + " old</p>\n" +
  "<strong>\"" + person.greeting + "\" is what I usually say</strong>";

let newHtmlStr =
 `<p>My name is ${person.name},</p>
  <p>I am ${person.age} old</p>
  <p>"${person.greeting}" is what I usually say</strong>`;

console.log(usualHtmlStr);
console.log(newHtmlStr);

As you can see, we used the ` around a series of characters, which are interpreted as a string literal, but any expressions of the form ${..} are parsed and evaluated inline immediately.

One really nice benefit of interpolated string literals is they are allowed to split across multiple lines:

var Actor = {"name": "RajiniKanth"};

var text =
`Now is the time for all good men like ${Actor.name}
to come to the aid of their
country!`;
console.log(text);
// Now is the time for all good men like RajiniKanth
// to come to the aid of their
// country!

Interpolated Expressions

Any valid expression is allowed to appear inside ${..} in an interpolated string literal, including function calls, inline function expression calls, and even other interpolated string literals!

function upper(s) {
  return s.toUpperCase();
}
var who = "reader"
var text =
`A very ${upper("warm")} welcome
to all of you ${upper(`${who}s`)}!`;
console.log(text);
// A very WARM welcome
// to all of you READERS!

Here, the inner `${who}s` interpolated string literal was a little bit nicer convenience for us when combining the who variable with the "s" string, as opposed to who + "s". Also to keep an note is an interpolated string literal is just lexically scoped where it appears, not dynamically scoped in any way:

function foo(str) {
  var name = "foo";
  console.log(str);
}
function bar() {
  var name = "bar";
  foo(`Hello from ${name}!`);
}
var name = "global";
bar(); // "Hello from bar!"

Using the template literal for the HTML is definitely more readable by reducing the annoyance.

The plain old way:

'<div class="' + className + '">' +
  '<p>' + content + '</p>' +
  '<a href="' + link + '">Let\'s go</a>'
'</div>';

With ECMAScript 6:

`<div class="${className}">
  <p>${content}</p>
  <a href="${link}">Let's go</a>
</div>`
  • Your string can span multiple lines.
  • You don't have to escape quotation characters.
  • You can avoid groupings like: '">'
  • You don't have to use the plus operator.

Tagged Template Literals

We can also tag a template string, when a template string is tagged, the literals and substitutions are passed to function which returns the resulting value.

function myTaggedLiteral(strings) {
  console.log(strings);
}

myTaggedLiteral`test`; //["test"]

function myTaggedLiteral(strings, value, value2) {
  console.log(strings, value, value2);
}
let someText = 'Neat';
myTaggedLiteral`test ${someText} ${2 + 3}`;
//["test", ""]
// "Neat"
// 5

We can use the spread operator here to pass multiple values. The first argument—we called it strings—is an array of all the plain strings (the stuff between any interpolated expressions).

We then gather up all subsequent arguments into an array called values using the ... gather/rest operator, though you could of course have left them as individual named parameters following the strings parameter like we did above (value1, value2, etc.).

function myTaggedLiteral(strings, ...values) {
  console.log(strings);
  console.log(values);
}

let someText = 'Neat';
myTaggedLiteral`test ${someText} ${2 + 3}`;
//["test", ""]
// "Neat"
// 5

The argument(s) gathered into our values array are the results of the already evaluated interpolation expressions found in the string literal. A tagged string literal is like a processing step after the interpolations are evaluated, but before the final string value is compiled, allowing you more control over generating the string from the literal. Let's look at an example of creating reusable templates.

const Actor = {
  name: "RajiniKanth",
  store: "Landmark"
}

const ActorTemplate = templater`<article>
  <h3>${'name'} is a Actor</h3>
  <p>You can find his movies at ${'store'}.</p>

</article>`;

function templater(strings, ...keys) {
  return function(data) {
    let temp = strings.slice();
    keys.forEach((key, i) => {
      temp[i] = temp[i] + data[key];
    });
    return temp.join('');
  }
};

const myTemplate = ActorTemplate(Actor);
console.log(myTemplate);

Raw Strings

Our tag functions receive a first argument we called strings, which is an array. But there’s an additional bit of data included: the raw unprocessed versions of all the strings. You can access those raw string values using the .raw property, like this:

function showraw(strings, ...values) {
  console.log(strings);
  console.log(strings.raw);
}
showraw`Hello\nWorld`;

As you can see, the raw version of the string preserves the escaped \n sequence, while the processed version of the string treats it like an unescaped real new-line. ECMAScript 6 comes with a built-in function that can be used as a string literal tag: String.raw(..). It simply passes through the raw versions of the strings:

console.log(`Hello\nWorld`);
/* "Hello
World" */

console.log(String.raw`Hello\nWorld`);
// "Hello\nWorld"

How to reload apache configuration for a site without restarting apache?

If you are using Ubuntu server, you can use systemctl

systemctl reload apache2

New self vs. new static

In addition to others' answers :

static:: will be computed using runtime information.

That means you can't use static:: in a class property because properties values :

Must be able to be evaluated at compile time and must not depend on run-time information.

class Foo {
    public $name = static::class;

}

$Foo = new Foo;
echo $Foo->name; // Fatal error

Using self::

class Foo {
    public $name = self::class;

}
$Foo = new Foo;
echo $Foo->name; // Foo

Please note that the Fatal error comment in the code i made doesn't indicate where the error happened, the error happened earlier before the object was instantiated as @Grapestain mentioned in the comments

Entity Framework Provider type could not be loaded?

I also had a similar problem

My problem was solved by doing the following:

enter image description here

enter image description here

Converting a column within pandas dataframe from int to string

In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))

In [17]: df
Out[17]: 
   A  B
0  0  1
1  2  3
2  4  5
3  6  7
4  8  9

In [18]: df.dtypes
Out[18]: 
A    int64
B    int64
dtype: object

Convert a series

In [19]: df['A'].apply(str)
Out[19]: 
0    0
1    2
2    4
3    6
4    8
Name: A, dtype: object

In [20]: df['A'].apply(str)[0]
Out[20]: '0'

Don't forget to assign the result back:

df['A'] = df['A'].apply(str)

Convert the whole frame

In [21]: df.applymap(str)
Out[21]: 
   A  B
0  0  1
1  2  3
2  4  5
3  6  7
4  8  9

In [22]: df.applymap(str).iloc[0,0]
Out[22]: '0'

df = df.applymap(str)

How to convert char* to wchar_t*?

Use a std::wstring instead of a C99 variable length array. The current standard guarantees a contiguous buffer for std::basic_string. E.g.,

std::wstring wc( cSize, L'#' );
mbstowcs( &wc[0], c, cSize );

C++ does not support C99 variable length arrays, and so if you compiled your code as pure C++, it would not even compile.

With that change your function return type should also be std::wstring.

Remember to set relevant locale in main.

E.g., setlocale( LC_ALL, "" ).

Cheers & hth.,

How to access nested elements of json object using getJSONArray method

This is for Nikola.

    public static JSONObject setProperty(JSONObject js1, String keys, String valueNew) throws JSONException {
    String[] keyMain = keys.split("\\.");
    for (String keym : keyMain) {
        Iterator iterator = js1.keys();
        String key = null;
        while (iterator.hasNext()) {
            key = (String) iterator.next();
            if ((js1.optJSONArray(key) == null) && (js1.optJSONObject(key) == null)) {
                if ((key.equals(keym)) && (js1.get(key).toString().equals(valueMain))) {
                    js1.put(key, valueNew);
                    return js1;
                }
            }
            if (js1.optJSONObject(key) != null) {
                if ((key.equals(keym))) {
                    js1 = js1.getJSONObject(key);
                    break;
                }
            }
            if (js1.optJSONArray(key) != null) {
                JSONArray jArray = js1.getJSONArray(key);
                JSONObject j;
                for (int i = 0; i < jArray.length(); i++) {
                    js1 = jArray.getJSONObject(i);
                    break;
                }
            }
        }
    }
    return js1;
}


public static void main(String[] args) throws IOException, JSONException {
    String text = "{ "key1":{ "key2":{ "key3":{ "key4":[ { "fieldValue":"Empty", "fieldName":"Enter Field Name 1" }, { "fieldValue":"Empty", "fieldName":"Enter Field Name 2" } ] } } } }";
    JSONObject json = new JSONObject(text);
    setProperty(json, "ke1.key2.key3.key4.fieldValue", "nikola");
    System.out.println(json.toString(4));

}

If it's help bro,Do not forget to up for my reputation)))

Key existence check in HashMap

if(map.get(key) != null || (map.get(key) == null && map.containsKey(key)))

window.onunload is not working properly in Chrome browser. Can any one help me?

I know this is old but I found the way to make unload work using Chrome

window.onbeforeunload = function () {
  myFunction();
};

java.sql.SQLException: Incorrect string value: '\xF0\x9F\x91\xBD\xF0\x9F...'

execute

show VARIABLES like "%char%”;

find character-set-server if is not utf8mb4.

set it in your my.cnf, like

vim /etc/my.cnf

add one line

character_set_server = utf8mb4

at last restart mysql

Concat all strings inside a List<string> using LINQ

String.Join(delimiter, list);

is sufficient.

Remove Rows From Data Frame where a Row matches a String

Just use the == with the negation symbol (!). If dtfm is the name of your data.frame:

dtfm[!dtfm$C == "Foo", ]

Or, to move the negation in the comparison:

dtfm[dtfm$C != "Foo", ]

Or, even shorter using subset():

subset(dtfm, C!="Foo")

Opening a remote machine's Windows C drive

By default, Windows makes the root of each drive available (provided you've got Administrator privileges) as (e.g.) \\server\c$. These are known as Administrative Shares.

Default behavior of "git push" without a branch specified

You can push current branch with command

git push origin HEAD

(took from here)

How to run travis-ci locally

I wasn't able to use the answers here as-is. For starters, as noted, the Travis help document on running jobs locally has been taken down. All of the blog entries and articles I found are based on that. The new "debug" mode doesn't appeal to me because I want to avoid the queue times and the Travis infrastructure until I've got some confidence I have gotten somewhere with my changes.

In my case I'm updating a Puppet module and I'm not an expert in Puppet, nor particularly experienced in Ruby, Travis, or their ecosystems. But I managed to build a workable test image out of tips and ideas in this article and elsewhere, and by examining the Travis CI build logs pretty closely.

I was unable to find recent images matching the names in the CI logs (for example, I could find travisci/ci-sardonyx, but could not find anything with "xenial" or with the same build name). From the logs it appears images are now transferred via AMQP instead of a mechanism more familiar to me.

I was able to find an image travsci/ubuntu-ruby:16.04 which matches the OS I'm targeting for my particular case. It does not have all the components used in the Travis CI, so I built a new one based on this, with some components added to the image and others added in the container at runtime depending on the need.

So I can't offer a clear procedure, sorry. But what I did, essentially boiled down:

  1. Find a recent Travis CI image in Docker Hub matching your target OS as closely as possible.

  2. Clone the repository to a build directory, and launch the container with the build directory mounted as a volume, with the working directory set to the target volume

  3. Now the hard work: go through the Travis build log and set up the environment. In my case, this meant setting up RVM, and then using bundle to install the project's dependencies. RVM appeared to be already present in the Travis environment but I had to install it; everything else came from reproducing the commands in the build log.

  4. Run the tests.

  5. If the results don't match what you saw in the Travis CI logs, go back to (3) and see where to go.

  6. Optionally, create a reusable image.

  7. Dev and test locally and then push and hopefully your Travis results will be as expected.

I know this is not concrete and may be obvious, and your mileage will definitely vary, but hopefully this is of some use to somebody. The Dockerfile and a README for my image are on GitHub for reference.

How to generate gcc debug symbol outside the build target?

You need to use objcopy to separate the debug information:

objcopy --only-keep-debug "${tostripfile}" "${debugdir}/${debugfile}"
strip --strip-debug --strip-unneeded "${tostripfile}"
objcopy --add-gnu-debuglink="${debugdir}/${debugfile}" "${tostripfile}"

I use the bash script below to separate the debug information into files with a .debug extension in a .debug directory. This way I can tar the libraries and executables in one tar file and the .debug directories in another. If I want to add the debug info later on I simply extract the debug tar file and voila I have symbolic debug information.

This is the bash script:

#!/bin/bash

scriptdir=`dirname ${0}`
scriptdir=`(cd ${scriptdir}; pwd)`
scriptname=`basename ${0}`

set -e

function errorexit()
{
  errorcode=${1}
  shift
  echo $@
  exit ${errorcode}
}

function usage()
{
  echo "USAGE ${scriptname} <tostrip>"
}

tostripdir=`dirname "$1"`
tostripfile=`basename "$1"`


if [ -z ${tostripfile} ] ; then
  usage
  errorexit 0 "tostrip must be specified"
fi

cd "${tostripdir}"

debugdir=.debug
debugfile="${tostripfile}.debug"

if [ ! -d "${debugdir}" ] ; then
  echo "creating dir ${tostripdir}/${debugdir}"
  mkdir -p "${debugdir}"
fi
echo "stripping ${tostripfile}, putting debug info into ${debugfile}"
objcopy --only-keep-debug "${tostripfile}" "${debugdir}/${debugfile}"
strip --strip-debug --strip-unneeded "${tostripfile}"
objcopy --add-gnu-debuglink="${debugdir}/${debugfile}" "${tostripfile}"
chmod -x "${debugdir}/${debugfile}"

Visual C++: How to disable specific linker warnings?

The PDB file is typically used to store debug information. This warning is caused probably because the file vc80.pdb is not found when linking the target object file. Read the MSDN entry on LNK4099 here.

Alternatively, you can turn off debug information generation from the Project Properties > Linker > Debugging > Generate Debug Info field.

Where to put the gradle.properties file

Actually there are 3 places where gradle.properties can be placed:

  1. Under gradle user home directory defined by the GRADLE_USER_HOME environment variable, which if not set defaults to USER_HOME/.gradle
  2. The sub-project directory (myProject2 in your case)
  3. The root project directory (under myProject)

Gradle looks for gradle.properties in all these places while giving precedence to properties definition based on the order above. So for example, for a property defined in gradle user home directory (#1) and the sub-project (#2) its value will be taken from gradle user home directory (#1).

You can find more details about it in gradle documentation here.

How can I lookup a Java enum from its String value?

You can use the Enum::valueOf() function as suggested by Gareth Davis & Brad Mace above, but make sure you handle the IllegalArgumentException that would be thrown if the string used is not present in the enum.

How to catch a unique constraint error in a PL/SQL block?

I'm sure you have your reasons, but just in case... you should also consider using a "merge" query instead:

begin
    merge into some_table st
    using (select 'some' name, 'values' value from dual) v
    on (st.name=v.name)
    when matched then update set st.value=v.value
    when not matched then insert (name, value) values (v.name, v.value);
end;

(modified the above to be in the begin/end block; obviously you can run it independantly of the procedure too).

How to get cookie's expire time

To get cookies expire time, use this simple method.

<?php

//#############PART 1#############
//expiration time (a*b*c*d) <- change D corresponding to number of days for cookie expiration
$time = time()+(60*60*24*365);
$timeMemo = (string)$time;

//sets cookie with expiration time defined above
setcookie("testCookie", "" . $timeMemo . "", $time);

//#############PART 2#############
//this function will convert seconds to days.
function secToDays($sec){

    return ($sec / 60 / 60 / 24);

}
//checks if cookie is set and prints out expiration time in days
if(isset($_COOKIE['testCookie'])){

    echo "Cookie is set<br />";
    if(round(secToDays((intval($_COOKIE['testCookie']) - time())),1) < 1){
        echo "Cookie will expire today.";
    }else{
        echo "Cookie will expire in " . round(secToDays((intval($_COOKIE['testCookie']) - time())),1) . " day(s)";
    }

}else{
    echo "not set...";
}

?>

You need to keep Part 1 and Part 2 in different files, otherwise you will get the same expire date everytime.

How to read keyboard-input?

try

raw_input('Enter your input:')  # If you use Python 2
input('Enter your input:')      # If you use Python 3

and if you want to have a numeric value just convert it:

try:
    mode=int(raw_input('Input:'))
except ValueError:
    print "Not a number"

Maven and Spring Boot - non resolvable parent pom - repo.spring.io (Unknown host)

Just a remind: I tried to work with idea and imported maven, and encountered the same problem, I have tried all the solutions and they didnt work. Finally, I found out it was because of the root access... I opened idea with administrator access and all things work just fine, hope you not as silly as i am...

What does yield mean in PHP?

An interesting aspect, which worth to be discussed here, is yielding by reference. Every time we need to change a parameter such that it is reflected outside of the function, we have to pass this parameter by reference. To apply this to generators, we simply prepend an ampersand & to the name of the generator and to the variable used in the iteration:

 <?php 
 /**
 * Yields by reference.
 * @param int $from
 */
function &counter($from) {
    while ($from > 0) {
        yield $from;
    }
}

foreach (counter(100) as &$value) {
    $value--;
    echo $value . '...';
}

// Output: 99...98...97...96...95...

The above example shows how changing the iterated values within the foreach loop changes the $from variable within the generator. This is because $from is yielded by reference due to the ampersand before the generator name. Because of that, the $value variable within the foreach loop is a reference to the $from variable within the generator function.

Access denied; you need (at least one of) the SUPER privilege(s) for this operation

Need to set "on" server parameter "log_bin_trust_function_creators" on server side. This one you can easily find on left side blade if it is azure maria db.

ORA-00979 not a group by expression

Same error also come when UPPER or LOWER keyword not used in both place in select expression and group by expression .

Wrong :-

select a , count(*) from my_table group by UPPER(a) .

Right :-

select UPPER(a) , count(*) from my_table group by UPPER(a) .

Pass array to MySQL stored routine

Use a join with a temporary table. You don't need to pass temporary tables to functions, they are global.

create temporary table ids( id int ) ;
insert into ids values (1),(2),(3) ;

delimiter //
drop procedure if exists tsel //
create procedure tsel() -- uses temporary table named ids. no params
READS SQL DATA
BEGIN
  -- use the temporary table `ids` in the SELECT statement or
  -- whatever query you have
  select * from Users INNER JOIN ids on userId=ids.id ;
END //
DELIMITER ;

CALL tsel() ; -- call the procedure

Why are only final variables accessible in anonymous class?

An anonymous class is an inner class and the strict rule applies to inner classes (JLS 8.1.3):

Any local variable, formal method parameter or exception handler parameter used but not declared in an inner class must be declared final. Any local variable, used but not declared in an inner class must be definitely assigned before the body of the inner class.

I haven't found a reason or an explanation on the jls or jvms yet, but we do know, that the compiler creates a separate class file for each inner class and it has to make sure, that the methods declared on this class file (on byte code level) at least have access to the values of local variables.

(Jon has the complete answer - I keep this one undeleted because one might interested in the JLS rule)

Custom Drawable for ProgressBar/ProgressDialog

I used the following for creating a custom progress bar.

File res/drawable/progress_bar_states.xml declares the colors of the different states:

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:id="@android:id/background">
        <shape>
            <gradient
                    android:startColor="#000001"
                    android:centerColor="#0b131e"
                    android:centerY="0.75"
                    android:endColor="#0d1522"
                    android:angle="270"
            />
        </shape>
    </item>

    <item android:id="@android:id/secondaryProgress">
        <clip>
            <shape>
                <gradient
                        android:startColor="#234"
                        android:centerColor="#234"
                        android:centerY="0.75"
                        android:endColor="#a24"
                        android:angle="270"
                />
            </shape>
        </clip>
    </item>

    <item android:id="@android:id/progress">
        <clip>
            <shape>
                <gradient
                    android:startColor="#144281"
                    android:centerColor="#0b1f3c"
                    android:centerY="0.75"
                    android:endColor="#06101d"
                    android:angle="270"
                />
            </shape>
        </clip>
    </item>

</layer-list>

And the code inside your layout xml:

<ProgressBar android:id="@+id/progressBar"
    android:progressDrawable="@drawable/progress_bar_states"
    android:layout_width="fill_parent" android:layout_height="8dip" 
    style="?android:attr/progressBarStyleHorizontal" 
    android:indeterminateOnly="false" 
    android:max="100">
</ProgressBar>

Enjoy!

"Please try running this command again as Root/Administrator" error when trying to install LESS

Re Explosion Pills "An installation can run arbitrary scripts and running it with sudo can be extremely dangerous!"

Seems like using sudo is the wrong way of doing it.

"Change the owner of the files in your /usr/local folder to the current user:"

sudo chown -R $USER /usr/local

Then run the install

node install -g less

Check out:

Is this a good way to clone an object in ES6?

You can do it like this as well,

let copiedData = JSON.parse(JSON.stringify(data));

Unable to find valid certification path to requested target - error even after cert imported

I am working on a tutorial for REST web services at www.udemy.com (REST Java Web Services). The example in the tutorial said that in order to have SSL, we must have a folder called "trust_store" in my eclipse "client" project that should contain a "key store" file (we had a "client" project to call the service, and "service" project that contained the REST web service - 2 projects in the same eclipse workspace, one the client, the other the service). To keep things simple, they said to copy "keystore.jks" from the glassfish app server (glassfish\domains\domain1\config\keystore.jks) we are using and put it into this "trust_store" folder that they had me make in the client project. That seems to make sense: the self-signed certs in the server's key_store would correspond to the certs in the client trust_store. Now, doing this, I was getting the error that the original post mentions. I have googled this and read that the error is due to the "keystore.jks" file on the client not containing a trusted/signed certificate, that the certificate it finds is self-signed.

To keep things clear, let me say that as I understand it, the "keystore.jks" contains self-signed certs, and the "cacerts.jks" file contains CA certs (signed by the CA). The "keystore.jks" is the "keystore" and the "cacerts.jks" is the "trust store". As "Bruno", a commenter, says above, "keystore.jks" is local, and "cacerts.jks" is for remote clients.

So, I said to myself, hey, glassfish also has the "cacerts.jks" file, which is glassfish's trust_store file. cacerts.jsk is supposed to contain CA certificates. And apparently I need my trust_store folder to contain a key store file that has at least one CA certificate. So, I tried putting the "cacerts.jks" file in the "trust_store" folder I had made, on my client project, and changing the VM properties to point to "cacerts.jks" instead of "keystore.jks". That got rid of the error. I guess all it needed was a CA cert to work.

This may not be ideal for production, or even for development beyond just getting something to work. For instance you could probably use "keytool" command to add CA certs to the "keystore.jks" file in the client. But anyway hopefully this at least narrows down the possible scenarios that could be going on here to cause the error.

ALSO: my approach seemed to be useful for the client (server cert added to client trust_store), it looks like the comments above to resolve the original post are useful for the server (client cert added to server trust_store). Cheers.

Eclipse project setup:

  • MyClientProject
  • src
  • test
  • JRE System Library
  • ...
  • trust_store
    ---cacerts.jks ---keystore.jks

Snippet from MyClientProject.java file:

static {
  // Setup the trustStore location and password
  System.setProperty("javax.net.ssl.trustStore","trust_store/cacerts.jks");
  // comment out below line
  System.setProperty("javax.net.ssl.trustStore","trust_store/keystore.jks");
  System.setProperty("javax.net.ssl.trustStorePassword", "changeit");
  //System.setProperty("javax.net.debug", "all");

  // for localhost testing only
  javax.net.ssl.HttpsURLConnection.setDefaultHostnameVerifier(new javax.net.ssl.HostnameVerifier() {
        public boolean verify(String hostname, javax.net.ssl.SSLSession sslSession) {
          return hostname.equals("localhost");
        }

  });
}

C# Call a method in a new thread

If you actually start a new thread, that thread will terminate when the method finishes:

Thread thread = new Thread(SecondFoo);
thread.Start();

Now SecondFoo will be called in the new thread, and the thread will terminate when it completes.

Did you actually mean that you wanted the thread to terminate when the method in the calling thread completes?

EDIT: Note that starting a thread is a reasonably expensive operation. Do you definitely need a brand new thread rather than using a threadpool thread? Consider using ThreadPool.QueueUserWorkItem or (preferrably, if you're using .NET 4) TaskFactory.StartNew.

A formula to copy the values from a formula to another column

You can use =A4, in case A4 is having long formula

Adding a favicon to a static HTML page

Note that FF fails to load an icon with a redundant // in URL like /img//favicon.png. Tested on FF 53. Chrome is OK.

Returning anonymous type in C#

Another option could be using automapper: You will be converting to any type from your anonymous returned object as long public properties matches. The key points are, returning object, use linq and autommaper. (or use similar idea returning serialized json, etc. or use reflection..)

using System.Linq;
using System.Reflection;
using AutoMapper;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Newtonsoft.Json;

namespace UnitTestProject1
{
    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public void TestMethod1()
        {
            var data = GetData();

            var firts = data.First();

            var info = firts.GetType().GetProperties(BindingFlags.Instance | BindingFlags.Public).First(p => p.Name == "Name");
            var value = info.GetValue(firts);

            Assert.AreEqual(value, "One");
        }


        [TestMethod]
        public void TestMethod2()
        {
            var data = GetData();

            var config = new MapperConfiguration(cfg => cfg.CreateMissingTypeMaps = true);
            var mapper = config.CreateMapper();

            var users = data.Select(mapper.Map<User>).ToArray();

            var firts = users.First();

            Assert.AreEqual(firts.Name, "One");

        }

        [TestMethod]
        public void TestMethod3()
        {
            var data = GetJData();


            var users = JsonConvert.DeserializeObject<User[]>(data);

            var firts = users.First();

            Assert.AreEqual(firts.Name, "One");

        }

        private object[] GetData()
        {

            return new[] { new { Id = 1, Name = "One" }, new { Id = 2, Name = "Two" } };
        }

        private string GetJData()
        {

            return JsonConvert.SerializeObject(new []{ new { Id = 1, Name = "One" }, new { Id = 2, Name = "Two" } }, Formatting.None);
        }

        public class User
        {
            public int Id { get; set; }
            public string Name { get; set; }
        }
    }

}

How to expand/collapse a diff sections in Vimdiff?

set vimdiff to ignore case

Having started vim diff with

 gvim -d main.sql backup.sql &

I find that annoyingly one file has MySQL keywords in lowercase the other uppercase showing differences on practically every other line

:set diffopt+=icase

this updates the screen dynamically & you can just as easily switch it off again

How do you add a timer to a C# console application

doc

There you have it :)

public static void Main()
   {
      SetTimer();

      Console.WriteLine("\nPress the Enter key to exit the application...\n");
      Console.WriteLine("The application started at {0:HH:mm:ss.fff}", DateTime.Now);
      Console.ReadLine();
      aTimer.Stop();
      aTimer.Dispose();

      Console.WriteLine("Terminating the application...");
   }

   private static void SetTimer()
   {
        // Create a timer with a two second interval.
        aTimer = new System.Timers.Timer(2000);
        // Hook up the Elapsed event for the timer. 
        aTimer.Elapsed += OnTimedEvent;
        aTimer.AutoReset = true;
        aTimer.Enabled = true;
    }

    private static void OnTimedEvent(Object source, ElapsedEventArgs e)
    {
        Console.WriteLine("The Elapsed event was raised at {0:HH:mm:ss.fff}",
                          e.SignalTime);
    }

Angular2 handling http response

The service :

import 'rxjs/add/operator/map';

import { Http } from '@angular/http';
import { Observable } from "rxjs/Rx"
import { Injectable } from '@angular/core';

@Injectable()
export class ItemService {
  private api = "your_api_url";

  constructor(private http: Http) {

  }

  toSaveItem(item) {
    return new Promise((resolve, reject) => {
      this.http
        .post(this.api + '/items', { item: item })
        .map(res => res.json())
        // This catch is very powerfull, it can catch all errors
        .catch((err: Response) => {
          // The err.statusText is empty if server down (err.type === 3)
          console.log((err.statusText || "Can't join the server."));
          // Really usefull. The app can't catch this in "(err)" closure
          reject((err.statusText || "Can't join the server."));
          // This return is required to compile but unuseable in your app
          return Observable.throw(err);
        })
        // The (err) => {} param on subscribe can't catch server down error so I keep only the catch
        .subscribe(data => { resolve(data) })
    })
  }
}

In the app :

this.itemService.toSaveItem(item).then(
  (res) => { console.log('success', res) },
  (err) => { console.log('error', err) }
)

Executing multiple SQL queries in one statement with PHP

With mysqli you're able to use multiple statements for real using mysqli_multi_query().

Read more on multiple statements in the PHP Docs.

Printing the value of a variable in SQL Developer

Make server output on First of all

  1. SET SERVEROUTPUT on then

  2. Go to the DBMS Output window (View->DBMS Output)

  3. then Press Ctrl+N for connecting server

How to set thymeleaf th:field value from other variable

So what you need to do is replace th:field with th:name and add th:value, th:value will have the value of the variable you're passing across.

<div class="col-auto">
        <input type="text" th:value="${client.name}" th:name="clientName" 
        class="form control">
</div>

How do I get the APK of an installed app without root access?

On Nougat(7.0) Android version run adb shell pm list packages to list the packages installed on the device. Then run adb shell pm path your-package-name to show the path of the apk. After use adb to copy the package to Downloads adb shell cp /data/app/com.test-1/base.apk /storage/emulated/0/Download. Then pull the apk from Downloads to your machine by running adb pull /storage/emulated/0/Download/base.apk.

Should a RESTful 'PUT' operation return something

Http response code of 201 for "Created" along with a "Location" header to point to where the client can find the newly created resource.

3 column layout HTML/CSS

Something like this should do it:

.column-left{ float: left; width: 33.333%; }
.column-right{ float: right; width: 33.333%; }
.column-center{ display: inline-block; width: 33.333%; }

DEMO

EDIT

To do this with a larger number of columns you could build a very simple grid system. For example, something like this should work for a five column layout:

_x000D_
_x000D_
.column {_x000D_
    float: left;_x000D_
    position: relative;_x000D_
    width: 20%;_x000D_
  _x000D_
    /*for demo purposes only */_x000D_
    background: #f2f2f2;_x000D_
    border: 1px solid #e6e6e6;_x000D_
    box-sizing: border-box;_x000D_
}_x000D_
_x000D_
.column-offset-1 {_x000D_
    left: 20%;_x000D_
}_x000D_
.column-offset-2 {_x000D_
    left: 40%;_x000D_
}_x000D_
.column-offset-3 {_x000D_
    left: 60%;_x000D_
}_x000D_
.column-offset-4 {_x000D_
    left: 80%;_x000D_
}_x000D_
_x000D_
.column-inset-1 {_x000D_
    left: -20%;_x000D_
}_x000D_
.column-inset-2 {_x000D_
    left: -40%;_x000D_
}_x000D_
.column-inset-3 {_x000D_
    left: -60%;_x000D_
}_x000D_
.column-inset-4 {_x000D_
    left: -80%;_x000D_
}
_x000D_
<div class="container">_x000D_
   <div class="column column-one column-offset-2">Column one</div>_x000D_
   <div class="column column-two column-inset-1">Column two</div>_x000D_
   <div class="column column-three column-offset-1">Column three</div>_x000D_
   <div class="column column-four column-inset-2">Column four</div>_x000D_
   <div class="column column-five">Column five</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Or, if you are lucky enough to be able to support only modern browsers, you can use flexible boxes:

_x000D_
_x000D_
.container {_x000D_
    display: flex;_x000D_
}_x000D_
_x000D_
.column {_x000D_
    flex: 1;_x000D_
    _x000D_
    /*for demo purposes only */_x000D_
    background: #f2f2f2;_x000D_
    border: 1px solid #e6e6e6;_x000D_
    box-sizing: border-box;_x000D_
}_x000D_
_x000D_
.column-one {_x000D_
    order: 3;_x000D_
}_x000D_
.column-two {_x000D_
    order: 1;_x000D_
}_x000D_
.column-three {_x000D_
    order: 4;_x000D_
}_x000D_
.column-four {_x000D_
    order: 2;_x000D_
}_x000D_
.column-five {_x000D_
    order: 5;_x000D_
}
_x000D_
<div class="container">_x000D_
   <div class="column column-one">Column one</div>_x000D_
   <div class="column column-two">Column two</div>_x000D_
   <div class="column column-three">Column three</div>_x000D_
   <div class="column column-four">Column four</div>_x000D_
   <div class="column column-five">Column five</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to programmatically set drawableLeft on Android button?

Following is the way to change the color of the left icon in edit text and set it in left side.

 Drawable img = getResources().getDrawable( R.drawable.user );
img.setBounds( 0, 0, 60, 60 );
mNameEditText.setCompoundDrawables(img,null, null, null);

int color = ContextCompat.getColor(this, R.color.blackColor);

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
    DrawableCompat.setTint(img, color);

} else {
    img.mutate().setColorFilter(color, PorterDuff.Mode.SRC_IN);
}

Can two Java methods have same name with different return types?

If both methods have same parameter types, but different return type than it is not possible. From Java Language Specification, Java SE 8 Edition, §8.4.2. Method Signature:

Two methods or constructors, M and N, have the same signature if they have the same name, the same type parameters (if any) (§8.4.4), and, after adapting the formal parameter types of N to the the type parameters of M, the same formal parameter types.

If both methods has different parameter types (so, they have different signature), then it is possible. It is called overloading.

How to set width of mat-table column in angular?

Just add style="width:5% !important;" to th and td

  <ng-container matColumnDef="username">
    <th style="width:5% !important;" mat-header-cell *matHeaderCellDef> Full Name </th>
    <td style="width:5% !important;" mat-cell *matCellDef="let element"> {{element.username}} ( {{element.usertype}} )</td>
  </ng-container>

What is the symbol for whitespace in C?

#include <stdio.h>
main()
{
int c,sp,tb,nl;
sp = 0;
tb = 0;
nl = 0;
while((c = getchar()) != EOF)
{
   switch( c )
{
   case ' ':
        ++sp;
     printf("space:%d\n", sp);
     break;
   case  '\t':
        ++tb;
     printf("tab:%d\n", tb);
     break;
   case '\n':
        ++nl;
     printf("new line:%d\n", nl);
     break;
  }
 }
}

Node.js Mongoose.js string to ObjectId function

I couldn't resolve this method (admittedly I didn't search for long)

mongoose.mongo.BSONPure.ObjectID.fromHexString

If your schema expects the property to be of type ObjectId, the conversion is implicit, at least this seems to be the case in 4.7.8.

You could use something like this however, which gives a bit more flex:

function toObjectId(ids) {

    if (ids.constructor === Array) {
        return ids.map(mongoose.Types.ObjectId);
    }

    return mongoose.Types.ObjectId(ids);
}

get one item from an array of name,value JSON

Find one element

To find the element with a given name in an array you can use find:

arr.find(item=>item.name=="k1");

Note that find will return just one item (namely the first match):

{
  "name": "k1",
  "value": "abc"
}

Find all elements

In your original array there's only one item occurrence of each name.

If the array contains multiple elements with the same name and you want them all then use filter, which will return an array.

_x000D_
_x000D_
var arr = [];_x000D_
arr.push({name:"k1", value:"abc"});_x000D_
arr.push({name:"k2", value:"hi"});_x000D_
arr.push({name:"k3", value:"oa"});_x000D_
arr.push({name:"k1", value:"def"});_x000D_
_x000D_
var item;_x000D_
_x000D_
// find the first occurrence of item with name "k1"_x000D_
item = arr.find(item=>item.name=="k1");_x000D_
console.log(item);_x000D_
_x000D_
// find all occurrences of item with name "k1"_x000D_
// now item is an array_x000D_
item = arr.filter(item=>item.name=="k1");_x000D_
console.log(item);
_x000D_
_x000D_
_x000D_

Find indices

Similarly, for indices you can use findIndex (for finding the first match) and filter + map to find all indices.

_x000D_
_x000D_
var arr = [];_x000D_
arr.push({name:"k1", value:"abc"});_x000D_
arr.push({name:"k2", value:"hi"});_x000D_
arr.push({name:"k3", value:"oa"});_x000D_
arr.push({name:"k1", value:"def"});_x000D_
_x000D_
var idx;_x000D_
_x000D_
// find index of the first occurrence of item with name "k1"_x000D_
idx = arr.findIndex(item=>item.name == "k1");_x000D_
console.log(idx, arr[idx].value);_x000D_
_x000D_
// find indices of all occurrences of item with name "k1"_x000D_
// now idx is an array_x000D_
idx = arr.map((item, i) => item.name == "k1" ? i : '').filter(String);_x000D_
console.log(idx);
_x000D_
_x000D_
_x000D_