Programs & Examples On #Sql generation

Why does an SSH remote command get fewer environment variables then when run manually?

How about sourcing the profile before running the command?

ssh user@host "source /etc/profile; /path/script.sh"

You might find it best to change that to ~/.bash_profile, ~/.bashrc, or whatever.

(As here (linuxquestions.org))

Flask SQLAlchemy query, specify column names

You can use load_only function:

from sqlalchemy.orm import load_only

fields = ['name', 'addr', 'phone', 'url']
companies = session.query(SomeModel).options(load_only(*fields)).all()

Run chrome in fullscreen mode on Windows

I would like to share my way of starting chrome - specificaly youtube tv - in full screen mode automatically, without the need of pressing F11. kiosk/fullscreen options doesn't seem to work (Version 41.0.2272.89). It has some steps though...

  • Start chrome and navigate to page (www.youtube.com/tv)
  • Drag the address from the address bar (the lock icon) to the desktop. It will create a shortcut.
  • From chrome, open Apps (the icon with the multiple coloured dots)
  • From desktop, drag the shortcut into the Apps space
  • Right click on the new icon in Apps and select "Open fullscreen"
  • Right click again on the icon in Apps and select "Create shortcuts..."
  • Select for example Desktop and Create. A new shortcut will be created on desktop.

Now, whenever you click on this shortcut, chrome will start in fullscreen and at the page you defined. I guess you can put this shortcut in startup folder to run when windows starts, but I haven't tried it.

Amazon Linux: apt-get: command not found

For openSUSE Linux distribution:

sudo zypper install <package>

For example:

sudo zypper install git

PYODBC--Data source name not found and no default driver specified

I have had the same error on python3 and this help me:

conn = pyodbc.connect('DRIVER={ODBC Driver 17 for SQL Server};'
                      'SERVER=YourServerName;'
                      'DATABASE=YourDatabaseName;UID=USER_NAME;PWD=PASS_WORD;')

remember python is case-sensitive so you have to mention DRIVER,SERVER,... in upper case. and you can visit this link for more information:

https://docs.microsoft.com/en-us/sql/connect/python/pyodbc/step-3-proof-of-concept-connecting-to-sql-using-pyodbc?view=sql-server-ver15

How do I prevent Conda from activating the base environment by default?

I faced the same problem. Initially I deleted the .bash_profile but this is not the right way. After installing anaconda it is showing the instructions clearly for this problem. Please check the image for solution provided by Anaconda

How to ISO 8601 format a Date with Timezone Offset in JavaScript?

You can achieve this with a few simple extension methods. The following Date extension method returns just the timezone component in ISO format, then you can define another for the date/time part and combine them for a complete date-time-offset string.

Date.prototype.getISOTimezoneOffset = function () {
    const offset = this.getTimezoneOffset();
    return (offset < 0 ? "+" : "-") + Math.floor(Math.abs(offset / 60)).leftPad(2) + ":" + (Math.abs(offset % 60)).leftPad(2);
}

Date.prototype.toISOLocaleString = function () {
    return this.getFullYear() + "-" + (this.getMonth() + 1).leftPad(2) + "-" +
        this.getDate().leftPad(2) + "T" + this.getHours().leftPad(2) + ":" +
        this.getMinutes().leftPad(2) + ":" + this.getSeconds().leftPad(2) + "." +
        this.getMilliseconds().leftPad(3);
}

Number.prototype.leftPad = function (size) {
    var s = String(this);
    while (s.length < (size || 2)) {
        s = "0" + s;
    }
    return s;
}

Example usage:

var date = new Date();
console.log(date.toISOLocaleString() + date.getISOTimezoneOffset());
// Prints "2020-08-05T16:15:46.525+10:00"

I know it's 2020 and most people are probably using Moment.js by now, but a simple copy & pastable solution is still sometimes handy to have.

(The reason I split the date/time and offset methods is because I'm using an old Datejs library which already provides a flexible toString method with custom format specifiers, but just doesn't include the timezone offset. Hence, I added toISOLocaleString for anyone without said library.)

Simple dictionary in C++

Until I was really concerned about performance, I would use a function, that takes a base and returns its match:

char base_pair(char base)
{
    switch(base) {
        case 'T': return 'A';
        ... etc
        default: // handle error
    }
}

If I was concerned about performance, I would define a base as one fourth of a byte. 0 would represent A, 1 would represent G, 2 would represent C, and 3 would represent T. Then I would pack 4 bases into a byte, and to get their pairs, I would simply take the complement.

Java correct way convert/cast object to Double

If your Object represents a number, eg, such as an Integer, you can cast it to a Number then call the doubleValue() method.

Double asDouble(Object o) {
    Double val = null;
    if (o instanceof Number) {
        val = ((Number) o).doubleValue();
    }
    return val;
}

How to initialize HashSet values by construction?

Can use static block for initialization:

private static Set<Integer> codes1=
        new HashSet<Integer>(Arrays.asList(1, 2, 3, 4));

private static Set<Integer> codes2 =
        new HashSet<Integer>(Arrays.asList(5, 6, 7, 8));

private static Set<Integer> h = new HashSet<Integer>();

static{
    h.add(codes1);
    h.add(codes2);
}

How to position a DIV in a specific coordinates?

I cribbed this and added the 'px'; Works very well.

function getOffset(el) {
  el = el.getBoundingClientRect();
  return {
    left: (el.right + window.scrollX ) +'px',
    top: (el.top + window.scrollY ) +'px'
  }
}
to call: //Gets it to the right side
 el.style.top = getOffset(othis).top ; 
 el.style.left = getOffset(othis).left ; 

Converting string to number in javascript/jQuery

You can adding a + before the string without using parseInt and parseFloat and radix, Simply

sample:

var votevalue = +$('button').data('votevalue');

alert(typeof(votevalue));

How to align entire html body to the center?

I just stumbled on this old post, and while I'm sure user01 has long since found his answer, I found the current answers don't quite work. After playing around for a little bit using info provided by the others, I found a solution that worked in IE, Firefox, and Chrome. In CSS:

html, body {
    height: 100%;
}

html {
    display: table;
    margin: auto;
}

body {
    display: table-cell;
    vertical-align: middle;
}

This is almost identical to abernier's answer, but I found that including width would break the centering, as would omitting the auto margin. I hope anyone else who stumbles on this thread will find my answer helpful.

Note: Omit html, body { height: 100%; } to only center horizontally.

Trying to start a service on boot on Android

How to start service on device boot(autorun app, etc.)

For first: since version Android 3.1+ you don't receive BOOT_COMPLETE if user never started your app at least once or user "force closed" application. This was done to prevent malware automatically register service. This security hole was closed in newer versions of Android.

Solution:

Create app with activity. When user run it once app can receive BOOT_COMPLETE broadcast message.

For second: BOOT_COMPLETE is sent before external storage is mounted. If app is installed to external storage it won't receive BOOT_COMPLETE broadcast message.

In this case there is two solution:

  1. Install your app to internal storage
  2. Install another small app in internal storage. This app receives BOOT_COMPLETE and run second app on external storage.

If your app already installed in internal storage then code below can help you understand how to start service on device boot.


In Manifest.xml

Permission:

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

Register your BOOT_COMPLETED receiver:

<receiver android:name="org.yourapp.OnBoot">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"/>
    </intent-filter>
</receiver>

Register your service:

<service android:name="org.yourapp.YourCoolService" />

In receiver OnBoot.java:

public class OnBoot extends BroadcastReceiver
{

    @Override
    public void onReceive(Context context, Intent intent) 
    {
        // Create Intent
        Intent serviceIntent = new Intent(context, YourCoolService.class);
        // Start service
        context.startService(serviceIntent);

    }

 }

For HTC you maybe need also add in Manifest this code if device don't catch RECEIVE_BOOT_COMPLETED:

<action android:name="android.intent.action.QUICKBOOT_POWERON" />

Receiver now look like this:

<receiver android:name="org.yourapp.OnBoot">
    <intent-filter>
        <action android:name="android.intent.action.BOOT_COMPLETED"/>
        <action android:name="android.intent.action.QUICKBOOT_POWERON" />
    </intent-filter>
</receiver>

How to test BOOT_COMPLETED without restart emulator or real device? It's easy. Try this:

adb -s device-or-emulator-id shell am broadcast -a android.intent.action.BOOT_COMPLETED

How to get device id? Get list of connected devices with id's:

adb devices

adb in ADT by default you can find in:

adt-installation-dir/sdk/platform-tools

Enjoy! )

HTML to PDF with Node.js

In case you arrive here looking for a way to make PDF from view templates in Express, a colleague and I made express-template-to-pdf

which allows you to generate PDF from whatever templates you're using in Express - Pug, Nunjucks, whatever.

It depends on html-pdf and is written to use in your routes just like you use res.render:

const pdfRenderer = require('@ministryofjustice/express-template-to-pdf')

app.set('views', path.join(__dirname, 'views'))
app.set('view engine', 'pug')

app.use(pdfRenderer())

If you've used res.render then using it should look obvious:

app.use('/pdf', (req, res) => {
    res.renderPDF('helloWorld', { message: 'Hello World!' });
})

You can pass options through to html-pdf to control the PDF document page size etc

Merely building on the excellent work of others.

PANIC: Broken AVD system path. Check your ANDROID_SDK_ROOT value

ok i can run android from cordova, i changed ANDROID_HOME to,

export ANDROID_HOME=/usr/local/opt/android-sdk

How do I "decompile" Java class files?

JD-GUI is really good. You could just open a JAR file and browse through the code as if you are working on an IDE. Good stuff.

Listen for key press in .NET console app

Addressing cases that some of the other answers don't handle well:

  • Responsive: direct execution of keypress handling code; avoids the vagaries of polling or blocking delays
  • Optionality: global keypress is opt-in; otherwise the app should exit normally
  • Separation of concerns: less invasive listening code; operates independently of normal console app code.

Many of the solutions on this page involve polling Console.KeyAvailable or blocking on Console.ReadKey. While it's true that the .NET Console is not very cooperative here, you can use Task.Run to move towards a more modern Async mode of listening.

The main issue to be aware of is that, by default, your console thread isn't set up for Async operation--meaning that, when you fall out of the bottom of your main function, instead of awaiting Async completions, your AppDoman and process will end. A proper way to address this would be to use Stephen Cleary's AsyncContext to establish full Async support in your single-threaded console program. But for simpler cases, like waiting for a keypress, installing a full trampoline may be overkill.

The example below would be for a console program used in some kind of iterative batch file. In this case, when the program is done with its work, normally it should exit without requiring a keypress, and then we allow an optional key press to prevent the app from exiting. We can pause the cycle to examine things, possibly resuming, or use the pause as a known 'control point' at which to cleanly break out of the batch file.

static void Main(String[] args)
{
    Console.WriteLine("Press any key to prevent exit...");
    var tHold = Task.Run(() => Console.ReadKey(true));

    // ... do your console app activity ...

    if (tHold.IsCompleted)
    {
#if false   // For the 'hold' state, you can simply halt forever...
        Console.WriteLine("Holding.");
        Thread.Sleep(Timeout.Infinite);
#else                            // ...or allow continuing to exit
        while (Console.KeyAvailable)
            Console.ReadKey(true);     // flush/consume any extras
        Console.WriteLine("Holding. Press 'Esc' to exit.");
        while (Console.ReadKey(true).Key != ConsoleKey.Escape)
            ;
#endif
    }
}

Oracle: How to find out if there is a transaction pending?

Matthew Watson can be modified to be used in RAC

select t.inst_id 
       ,s.sid
      ,s.serial#
      ,s.username
      ,s.machine
      ,s.status
      ,s.lockwait
      ,t.used_ublk
      ,t.used_urec
      ,t.start_time
from gv$transaction t
inner join gv$session s on t.addr = s.taddr;

How to change Bootstrap's global default font size?

I just solved this type of problem. I was trying to increase

font-size to h4 size. I do not want to use h4 tag. I added my css after bootstrap.css it didn't work. The easiest way is this: On the HTML doc, type

<p class="h4">

You do not need to add anything to your css sheet. It works fine Question is suppose I want a size between h4 and h5? Answer why? Is this the only way to please your viewers? I will prefer this method to tampering with standard docs like bootstrap.

Shell - Write variable contents to a file

None of the answers above work if your variable:

  • starts with -e
  • starts with -n
  • starts with -E
  • contains a \ followed by an n
  • should not have an extra newline appended after it

and so they cannot be relied upon for arbitrary string contents.

In bash, you can use "here strings" as:

cat <<< "$var" > "$destdir"

As noted in the comment below, @Trebawa's answer (formulated in the same room as mine!) using printf is a better approach.

MySQL Daemon Failed to Start - centos 6

You may need free up some space from root (/) partition. Stop mysql process by:

/etc/init.d/mysql stop

Delete an unused database from mySql by command:

rm -rf [Database-Directory]

Execute it in /var/lib/mysql. Now if you run df -h, you may confused by still full space. For removing the unused database 's directory to be affected, you need to kill processes are using current directory/partition.

Stopping mysql_safe or mysqld_safe and then mysqld:

ps -A

Then find mysql's process number (e.g. 2234). Then execute:

kill 2234

Now start again mysql:

/etc/init.d/mysql start

Catching "Maximum request length exceeded"

One way to do this is to set the maximum size in web.config as has already been stated above e.g.

<system.web>         
    <httpRuntime maxRequestLength="102400" />     
</system.web>

then when you handle the upload event, check the size and if its over a specific amount, you can trap it e.g.

protected void btnUploadImage_OnClick(object sender, EventArgs e)
{
    if (fil.FileBytes.Length > 51200)
    {
         TextBoxMsg.Text = "file size must be less than 50KB";
    }
}

How to Detect if I'm Compiling Code with a particular Visual Studio version?

_MSC_VER should be defined to a specific version number. You can either #ifdef on it, or you can use the actual define and do a runtime test. (If for some reason you wanted to run different code based on what compiler it was compiled with? Yeah, probably you were looking for the #ifdef. :))

Find duplicate values in R

This will give you duplicate rows:

vocabulary[duplicated(vocabulary$id),]

This will give you the number of duplicates:

dim(vocabulary[duplicated(vocabulary$id),])[1]

Example:

vocabulary2 <-rbind(vocabulary,vocabulary[1,]) #creates a duplicate at the end
vocabulary2[duplicated(vocabulary2$id),]
#            id year    sex education vocabulary
#21639 20040001 2004 Female         9          3
dim(vocabulary2[duplicated(vocabulary2$id),])[1]
#[1] 1 #=1 duplicate

EDIT

OK, with the additional information, here's what you should do: duplicated has a fromLast option which allows you to get duplicates from the end. If you combine this with the normal duplicated, you get all duplicates. The following example adds duplicates to the original vocabulary object (line 1 is duplicated twice and line 5 is duplicated once). I then use table to get the total number of duplicates per ID.

#Create vocabulary object with duplicates
voc.dups <-rbind(vocabulary,vocabulary[1,],vocabulary[1,],vocabulary[5,])

#List duplicates
dups <-voc.dups[duplicated(voc.dups$id)|duplicated(voc.dups$id, fromLast=TRUE),]
dups
#            id year    sex education vocabulary
#1     20040001 2004 Female         9          3
#5     20040008 2004   Male        14          1
#21639 20040001 2004 Female         9          3
#21640 20040001 2004 Female         9          3
#51000 20040008 2004   Male        14          1

#Count duplicates by id
table(dups$id)
#20040001 20040008 
#       3        2 

Detect encoding and make everything UTF-8

@harpax that worked for me. In my case, this is good enough:

if (isUTF8($str)) { 
    echo $str; 
}
else
{
    echo iconv("ISO-8859-1", "UTF-8//TRANSLIT", $str);
}

JAVA_HOME and PATH are set but java -version still shows the old one

$JAVA_HOME/bin/java -version says 'Permission Denied'

If you cannot access or run code, it which be ignored if added to your path. You need to make it accessible and runnable or get a copy of your own.

Do an

ls -ld $JAVA_HOME $JAVA_HOME/bin $JAVA_HOME/bin/java

to see why you cannot access or run this program,.

How to finish Activity when starting other activity in Android?

Intent i = new Intent(this,Here is your first activity.Class);
    i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    startActivity(i);
    finish();

What is the difference between for and foreach?

for loop:

 1) need to specify the loop bounds( minimum or maximum).

  2) executes a statement or a block of statements repeatedly 
    until a specified expression evaluates to false.

Ex1:-

int K = 0;

for (int x = 1; x <= 9; x++){
        k = k + x ;
}

foreach statement:

1)do not need to specify the loop bounds minimum or maximum.

2)repeats a group of embedded statements for 
     a)each element in an array 
  or b) an object collection.       

Ex2:-

int k = 0;

int[] tempArr = new int[] { 0, 2, 3, 8, 17 };

foreach (int i in tempArr){
    k = k + i ;
}

Postgres: How to do Composite keys?

Your compound PRIMARY KEY specification already does what you want. Omit the line that's giving you a syntax error, and omit the redundant CONSTRAINT (already implied), too:

 CREATE TABLE tags
      (
               question_id INTEGER NOT NULL,
               tag_id SERIAL NOT NULL,
               tag1 VARCHAR(20),
               tag2 VARCHAR(20),
               tag3 VARCHAR(20),
               PRIMARY KEY(question_id, tag_id)
      );

NOTICE:  CREATE TABLE will create implicit sequence "tags_tag_id_seq" for serial column "tags.tag_id"
    NOTICE:  CREATE TABLE / PRIMARY KEY will create implicit index "tags_pkey" for table "tags"
    CREATE TABLE
    pg=> \d tags
                                         Table "public.tags"
       Column    |         Type          |                       Modifiers       
    -------------+-----------------------+-------------------------------------------------------
     question_id | integer               | not null
     tag_id      | integer               | not null default nextval('tags_tag_id_seq'::regclass)
     tag1        | character varying(20) |
     tag2        | character varying(20) |
     tag3        | character varying(20) |
    Indexes:
        "tags_pkey" PRIMARY KEY, btree (question_id, tag_id)

Is there a Java API that can create rich Word documents?

docx4j or poi, both of which are ASL v2

@wondersofcomputing: iText is actually free and open source

How do I shrink my SQL Server Database?

ALTER DATABASE MyDatabase SET RECOVERY SIMPLE

GO

DBCC SHRINKFILE (MyDatabase_Log, 5)

GO

ALTER DATABASE MyDatabase SET RECOVERY FULL

GO

How can I specify my .keystore file with Spring Boot and Tomcat?

If you don't want to implement your connector customizer, you can build and import the library (https://github.com/ycavatars/spring-boot-https-kit) which provides predefined connector customizer. According to the README, you only have to create your keystore, configure connector.https.*, import the library and add @ComponentScan("org.ycavatars.sboot.kit"). Then you'll have HTTPS connection.

Get the difference between dates in terms of weeks, months, quarters, and years

try this for a months solution

StartDate <- strptime("14 January 2013", "%d %B %Y") 
EventDates <- strptime(c("26 March 2014"), "%d %B %Y") 
difftime(EventDates, StartDate) 

Alternative to file_get_contents?

Yes, if you have URL wrappers disabled you should use sockets or, even better, the cURL library.

If it's part of your site then refer to it with the file system path, not the web URL. /var/www/..., rather than http://domain.tld/....

Html.BeginForm and adding properties

You can also use the following syntax for the strongly typed version:

<% using (Html.BeginForm<SomeController>(x=> x.SomeAction(), 
          FormMethod.Post, 
          new { enctype = "multipart/form-data" })) 
   { %>

How To Run PHP From Windows Command Line in WAMPServer

The PHP CLI as its called ( php for the Command Line Interface ) is called php.exe It lives in c:\wamp\bin\php\php5.x.y\php.exe ( where x and y are the version numbers of php that you have installed )

If you want to create php scrips to run from the command line then great its easy and very useful.

Create yourself a batch file like this, lets call it phppath.cmd :

PATH=%PATH%;c:\wamp\bin\php\phpx.y.z
php -v

Change x.y.z to a valid folder name for a version of PHP that you have installed within WAMPServer

Save this into one of your folders that is already on your PATH, so you can run it from anywhere.

Now from a command window, cd into your source folder and run >phppath.

Then run

php your_script.php

It should work like a dream.

Here is an example that configures PHP Composer and PEAR if required and they exist

@echo off

REM **************************************************************
REM * PLACE This file in a folder that is already on your PATH
REM * Or just put it in your C:\Windows folder as that is on the
REM * Search path by default
REM * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
REM * EDIT THE NEXT 3 Parameters to fit your installed WAMPServer
REM **************************************************************


set baseWamp=D:\wamp
set defaultPHPver=7.4.3
set composerInstalled=%baseWamp%\composer
set phpFolder=\bin\php\php

if %1.==. (
    set phpver=%baseWamp%%phpFolder%%defaultPHPver%
) else (
    set phpver=%baseWamp%%phpFolder%%1
)

PATH=%PATH%;%phpver%
php -v
echo ---------------------------------------------------------------


REM IF PEAR IS INSTALLED IN THIS VERSION OF PHP

IF exist %phpver%\pear (
    set PHP_PEAR_SYSCONF_DIR=%baseWamp%%phpFolder%%phpver%
    set PHP_PEAR_INSTALL_DIR=%baseWamp%%phpFolder%%phpver%\pear
    set PHP_PEAR_DOC_DIR=%baseWamp%%phpFolder%%phpver%\docs
    set PHP_PEAR_BIN_DIR=%baseWamp%%phpFolder%%phpver%
    set PHP_PEAR_DATA_DIR=%baseWamp%%phpFolder%%phpver%\data
    set PHP_PEAR_PHP_BIN=%baseWamp%%phpFolder%%phpver%\php.exe
    set PHP_PEAR_TEST_DIR=%baseWamp%%phpFolder%%phpver%\tests

    echo PEAR INCLUDED IN THIS CONFIG
    echo ---------------------------------------------------------------
) else (
    echo PEAR DOES NOT EXIST IN THIS VERSION OF php
    echo ---------------------------------------------------------------
)

REM IF A GLOBAL COMPOSER EXISTS ADD THAT TOO
REM **************************************************************
REM * IF A GLOBAL COMPOSER EXISTS ADD THAT TOO
REM *
REM * This assumes that composer is installed in /wamp/composer
REM *
REM **************************************************************
IF EXIST %composerInstalled% (
    ECHO COMPOSER INCLUDED IN THIS CONFIG
    echo ---------------------------------------------------------------
    set COMPOSER_HOME=%baseWamp%\composer
    set COMPOSER_CACHE_DIR=%baseWamp%\composer

    PATH=%PATH%;%baseWamp%\composer

    rem echo TO UPDATE COMPOSER do > composer self-update
    echo ---------------------------------------------------------------
) else (
    echo ---------------------------------------------------------------
    echo COMPOSER IS NOT INSTALLED
    echo ---------------------------------------------------------------
)

set baseWamp=
set defaultPHPver=
set composerInstalled=
set phpFolder=

Call this command file like this to use the default version of PHP

> phppath

Or to get a specific version of PHP like this

> phppath 5.6.30

How to use the ConfigurationManager.AppSettings

Your web.config file should have this structure:

<configuration>
    <connectionStrings>
        <add name="MyConnectionString" connectionString="..." />
    </connectionStrings>
</configuration>

Then, to create a SQL connection using the connection string named MyConnectionString:

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);

If you'd prefer to keep your connection strings in the AppSettings section of your configuration file, it would look like this:

<configuration>
    <appSettings>
        <add key="MyConnectionString" value="..." />
    </appSettings>
</configuration>

And then your SqlConnection constructor would look like this:

SqlConnection con = new SqlConnection(ConfigurationManager.AppSettings["MyConnectionString"]);

How can I remove space (margin) above HTML header?

It is probably the h1 tag causing the problem. Applying margin: 0; should fix the problem.

But you should use a CSS reset for every new project to eliminate browser consistencies and problems like yours. Probably the most famous one is Eric Meyer's: http://meyerweb.com/eric/tools/css/reset/

Script to get the HTTP status code of a list of urls?

This relies on widely available wget, present almost everywhere, even on Alpine Linux.

wget --server-response --spider --quiet "${url}" 2>&1 | awk 'NR==1{print $2}'

The explanations are as follow :

--quiet

Turn off Wget's output.

Source - wget man pages

--spider

[ ... ] it will not download the pages, just check that they are there. [ ... ]

Source - wget man pages

--server-response

Print the headers sent by HTTP servers and responses sent by FTP servers.

Source - wget man pages

What they don't say about --server-response is that those headers output are printed to standard error (sterr), thus the need to redirect to stdin.

The output sent to standard input, we can pipe it to awk to extract the HTTP status code. That code is :

  • the second ($2) non-blank group of characters: {$2}
  • on the very first line of the header: NR==1

And because we want to print it... {print $2}.

wget --server-response --spider --quiet "${url}" 2>&1 | awk 'NR==1{print $2}'

How can I work with command line on synology?

The current windows 10 (Version 1803 (OS Build 17134.1)) has SSH built in. With that, just enable SSH from the Control Panel, Terminal & SNMP, be sure you are using an account in the Administrator's group, and you're all set.

Launch Powershell or CMD, enter ssh yourAccountName@diskstation

The first time it will cache off your certificate.

EDIT:

Further detailed explanations can be found on the synology docs page:

How to login to DSM with root permission via SSH Telnet

Global npm install location on windows?

According to: https://docs.npmjs.com/files/folders

  • Local install (default): puts stuff in ./node_modules of the current package root.
  • Global install (with -g): puts stuff in /usr/local or wherever node is installed.
  • Install it locally if you're going to require() it.
  • Install it globally if you're going to run it on the command line. -> If you need both, then install it in both places, or use npm link.

prefix Configuration

The prefix config defaults to the location where node is installed. On most systems, this is /usr/local. On windows, this is the exact location of the node.exe binary.

The docs might be a little outdated, but they explain why global installs can end up in different directories:

(dev) go|c:\srv> npm config ls -l | grep prefix
; prefix = "C:\\Program Files\\nodejs" (overridden)
prefix = "C:\\Users\\bjorn\\AppData\\Roaming\\npm"

Based on the other answers, it may seem like the override is now the default location on Windows, and that I may have installed my office version prior to this override being implemented.

This also suggests a solution for getting all team members to have globals stored in the same absolute path relative to their PC, i.e. (run as Administrator):

mkdir %PROGRAMDATA%\npm
setx PATH "%PROGRAMDATA%\npm;%PATH%" /M
npm config set prefix %PROGRAMDATA%\npm

open a new cmd.exe window and reinstall all global packages.

Explanation (by lineno.):

  1. Create a folder in a sensible location to hold the globals (Microsoft is adamant that you shouldn't write to ProgramFiles, so %PROGRAMDATA% seems like the next logical place.
  2. The directory needs to be on the path, so use setx .. /M to set the system path (under HKEY_LOCAL_MACHINE). This is what requires you to run this in a shell with administrator permissions.
  3. Tell npm to use this new path. (Note: folder isn't visible in %PATH% in this shell, so you must open a new window).

What is the benefit of zerofill in MySQL?

When used in conjunction with the optional (nonstandard) attribute ZEROFILL, the default padding of spaces is replaced with zeros. For example, for a column declared as INT(4) ZEROFILL, a value of 5 is retrieved as 0005.

http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html

Create timestamp variable in bash script

And for my fellow Europeans, try using this:

timestamp=$(date +%d-%m-%Y_%H-%M-%S)

will give a format of the format: "15-02-2020_19-21-58"

You call the variable and get the string representation like this

$timestamp

How to animate a View with Translate Animation in Android

In order to move a View anywhere on the screen, I would recommend placing it in a full screen layout. By doing so, you won't have to worry about clippings or relative coordinates.

You can try this sample code:

main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" android:id="@+id/rootLayout">

    <Button
        android:id="@+id/btn1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="MOVE" android:layout_centerHorizontal="true"/>

    <ImageView
        android:id="@+id/img1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" android:layout_marginLeft="10dip"/>
    <ImageView
        android:id="@+id/img2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" android:layout_centerVertical="true" android:layout_alignParentRight="true"/>
    <ImageView
        android:id="@+id/img3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" android:layout_marginLeft="60dip" android:layout_alignParentBottom="true" android:layout_marginBottom="100dip"/>

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical" android:clipChildren="false" android:clipToPadding="false">

        <ImageView
            android:id="@+id/img4"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:src="@drawable/ic_launcher" android:layout_marginLeft="60dip" android:layout_marginTop="150dip"/>
    </LinearLayout>

</RelativeLayout>

Your activity

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    ((Button) findViewById( R.id.btn1 )).setOnClickListener( new OnClickListener()
    {
        @Override
        public void onClick(View v)
        {
            ImageView img = (ImageView) findViewById( R.id.img1 );              
            moveViewToScreenCenter( img );
            img = (ImageView) findViewById( R.id.img2 );
            moveViewToScreenCenter( img );
            img = (ImageView) findViewById( R.id.img3 );                
            moveViewToScreenCenter( img );
            img = (ImageView) findViewById( R.id.img4 );
            moveViewToScreenCenter( img );
        }
    });
}

private void moveViewToScreenCenter( View view )
{
    RelativeLayout root = (RelativeLayout) findViewById( R.id.rootLayout );
    DisplayMetrics dm = new DisplayMetrics();
    this.getWindowManager().getDefaultDisplay().getMetrics( dm );
    int statusBarOffset = dm.heightPixels - root.getMeasuredHeight();

    int originalPos[] = new int[2];
    view.getLocationOnScreen( originalPos );

    int xDest = dm.widthPixels/2;
    xDest -= (view.getMeasuredWidth()/2);
    int yDest = dm.heightPixels/2 - (view.getMeasuredHeight()/2) - statusBarOffset;

    TranslateAnimation anim = new TranslateAnimation( 0, xDest - originalPos[0] , 0, yDest - originalPos[1] );
    anim.setDuration(1000);
    anim.setFillAfter( true );
    view.startAnimation(anim);
}

The method moveViewToScreenCenter gets the View's absolute coordinates and calculates how much distance has to move from its current position to reach the center of the screen. The statusBarOffset variable measures the status bar height.

I hope you can keep going with this example. Remember that after the animation your view's position is still the initial one. If you tap the MOVE button again and again the same movement will repeat. If you want to change your view's position do it after the animation is finished.

How to print last two columns using awk

awk '{print $NF-1, $NF}'  inputfile

Note: this works only if at least two columns exist. On records with one column you will get a spurious "-1 column1"

No module named setuptools

For python3 is:

sudo apt-get install -y python3-setuptools

Java and SQLite

There is a new project SQLJet that is a pure Java implementation of SQLite. It doesn't support all of the SQLite features yet, but may be a very good option for some of the Java projects that work with SQLite databases.

How to check if a textbox is empty using javascript

Using this JavaScript will help you a lot. Some explanations are given within the code.

<script type="text/javascript">
    <!-- 
        function Blank_TextField_Validator()
        {
        // Check whether the value of the element 
        // text_name from the form named text_form is null
        if (!text_form.text_name.value)
        {
          // If it is display and alert box
           alert("Please fill in the text field.");
          // Place the cursor on the field for revision
           text_form.text_name.focus();
          // return false to stop further processing
           return (false);
        }
        // If text_name is not null continue processing
        return (true);
        }
        -->
</script>
<form name="text_form" method="get" action="#" 
    onsubmit="return Blank_TextField_Validator()">
    <input type="text" name="text_name" >
    <input type="submit" value="Submit">
</form>

Graph implementation C++

Here is a basic implementation of a graph. Note: I use vertex which is chained to next vertex. And each vertex has a list pointing to adjacent nodes.

#include <iostream>
using namespace std;


// 1 ->2 
// 1->4
// 2 ->3
// 4->3
// 4 -> 5
// Adjacency list
// 1->2->3-null
// 2->3->null
//4->5->null;

// Structure of a vertex
struct vertex {
   int i;
   struct node *list;
   struct vertex *next;
};
typedef struct vertex * VPTR;

// Struct of adjacency list
struct node {
    struct vertex * n;
    struct node *next;
};

typedef struct node * NODEPTR;

class Graph {
    public:
        // list of nodes chained together
        VPTR V;
        Graph() {
            V = NULL;
        }
        void addEdge(int, int);
        VPTR  addVertex(int);
        VPTR existVertex(int i);
        void listVertex();
};

// If vertex exist, it returns its pointer else returns NULL
VPTR Graph::existVertex(int i) {
    VPTR temp  = V;
    while(temp != NULL) {
        if(temp->i == i) {
            return temp;
        }
        temp = temp->next;
    }
   return NULL;
}
// Add a new vertex to the end of the vertex list
VPTR Graph::addVertex(int i) {
    VPTR temp = new(struct vertex);
    temp->list = NULL;
    temp->i = i;
    temp->next = NULL;

    VPTR *curr = &V;
    while(*curr) {
        curr = &(*curr)->next;
    }
    *curr = temp;
    return temp;
}

// Add a node from vertex i to j. 
// first check if i and j exists. If not first add the vertex
// and then add entry of j into adjacency list of i
void Graph::addEdge(int i, int j) {

    VPTR v_i = existVertex(i);   
    VPTR v_j = existVertex(j);   
    if(v_i == NULL) {
        v_i = addVertex(i);
    }
    if(v_j == NULL) {
        v_j = addVertex(j);
    }

    NODEPTR *temp = &(v_i->list);
    while(*temp) {
        temp = &(*temp)->next;
    }
    *temp = new(struct node);
    (*temp)->n = v_j;
    (*temp)->next = NULL;
}
// List all the vertex.
void Graph::listVertex() {
    VPTR temp = V;
    while(temp) {
        cout <<temp->i <<" ";
        temp = temp->next;
    }
    cout <<"\n";

}

// Client program
int main() {
    Graph G;
    G.addEdge(1, 2);
    G.listVertex();

}

With the above code, you can expand to do DFS/BFS etc.

Unexpected token < in first line of HTML

In my case I got this error because of a line

<script src="#"></script> 

Chrome tried to interpret the current HTML file then as javascript.

Java difference between FileWriter and BufferedWriter

You are right. Here is how write() method of BufferedWriter looks:

public void write(int c) throws IOException {
    synchronized (lock) {
        ensureOpen();
        if (nextChar >= nChars)
            flushBuffer();
        cb[nextChar++] = (char) c;
    }
}

As you can see it indeed checks whether the buffer is full (if (nextChar >= nChars)) and flushes the buffer. Then it adds new character to buffer (cb[nextChar++] = (char) c;).

Google drive limit number of download

This limit is indeed not specified, however their TOS mentions that: "FOR EXAMPLE, WE DON’T MAKE ANY COMMITMENTS ABOUT THE CONTENT WITHIN THE SERVICES, THE SPECIFIC FUNCTIONS OF THE SERVICES, OR THEIR RELIABILITY, AVAILABILITY, OR ABILITY TO MEET YOUR NEEDS. WE PROVIDE THE SERVICES “AS IS”. "

This means to me that the download limit is calculated based on a set of factors that describe the user and is subject to change from one to another.

Maybe using the TOR network may help you do your job.

How to Call a JS function using OnClick event

I removed your document.getElementById("Save").onclick = before your functions, because it's an event already being called on your button. I also had to call the two functions separately by the onclick event.

     <!DOCTYPE html>
      <html>
      <head>
      <script>
       function fun()
        {
         alert("hello");
         //validation code to see State field is mandatory.  
        }   
        function f1()
        {
          alert("f1 called");
           //form validation that recalls the page showing with supplied inputs.    
        }
      </script>
      </head>
      <body>
      <form name="form1" id="form1" method="post">
                State: 
                <select id="state ID">
                   <option></option>
                   <option value="ap">ap</option>
                   <option value="bp">bp</option>
                </select>
       </form>

       <table><tr><td id="Save" onclick="f1(); fun();">click</td></tr></table>

   </body>
   </html>

Task.Run with Parameter(s)?

From now you can also :

Action<int> action = (o) => Thread.Sleep(o);
int param = 10;
await new TaskFactory().StartNew(action, param)

Failed to connect to camera service

I came up with the same problem and I'm sharing how I fixed it. It may help some people.

First, check your Android version. If it is running on Android 6.0 and higher (API level 23+), then you need to :

  1. Declare a permission in the app manifest. Make sure to insert the permission above the application tag.

**<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />**

<application ...>
    ...
</application>

  1. Then, request that the user approve each permission at runtime

      if (ContextCompat.checkSelfPermission(thisActivity, Manifest.permission.CAMERA)
        != PackageManager.PERMISSION_GRANTED) {
    // here, Permission is not granted
    ActivityCompat.requestPermissions(this, new String[] {android.Manifest.permission.CAMERA}, 50);
    }
    

For more information, have a look at the API documentation here

Inserting into Oracle and retrieving the generated sequence ID

There are no auto incrementing features in Oracle for a column. You need to create a SEQUENCE object. You can use the sequence like:

insert into table(batch_id, ...) values(my_sequence.nextval, ...)

...to return the next number. To find out the last created sequence nr (in your session), you would use:

my_sequence.currval

This site has several complete examples on how to use sequences.

How do I enable Java in Microsoft Edge web browser?

You cannot open Java Applets (nor any other NPAPI plugin) in Microsoft Edge - they aren't supported and won't be added in the future.

Further you should be aware that in the next release of Google Chrome (v45 - due September 2015) NPAPI plugins will also no longer be supported.

Work-arounds

There are a couple of things that you can do:

Use Internet Explorer 11
You will find that in Windows 10 you will already have Internet Explorer 11 installed. IE 11 continues to support NPAPI (incl Java Applets). IE11 is squirrelled away (c:\program files\internet explorer\iexplore.exe). Just pin this exe to your task bar for easy access.

Use FireFox
You can also install and use a Firefox 32-bit Extended Support Release in Win10. Firefox have disabled NPAPI by default, but this can be overridden. This will only be supported until early 2018.

How to catch SQLServer timeout exceptions

Updated for c# 6:

    try
    {
        // some code
    }
    catch (SqlException ex) when (ex.Number == -2)  // -2 is a sql timeout
    {
        // handle timeout
    }

Very simple and nice to look at!!

How to create a new variable in a data.frame based on a condition?

One obvious and straightforward possibility is to use "if-else conditions". In that example

x <- c(1, 2, 4)
y <- c(1, 4, 5)
w <- ifelse(x <= 1, "good", ifelse((x >= 3) & (x <= 5), "bad", "fair"))
data.frame(x, y, w)

** For the additional question in the edit** Is that what you expect ?

> d1 <- c("e", "c", "a")
> d2 <- c("e", "a", "b")
> 
> w <- ifelse((d1 == "e") & (d2 == "e"), 1, 
+    ifelse((d1=="a") & (d2 == "b"), 2,
+    ifelse((d1 == "e"), 3, 99)))
>     
> data.frame(d1, d2, w)
  d1 d2  w
1  e  e  1
2  c  a 99
3  a  b  2

If you do not feel comfortable with the ifelse function, you can also work with the if and else statements for such applications.

How to return Json object from MVC controller to view

$.ajax({
    dataType: "json",
    type: "POST",
    url: "/Home/AutocompleteID",
    data: data,
    success: function (data) {
        $('#search').html('');
        $('#search').append(data[0].Scheme_Code);
        $('#search').append(data[0].Scheme_Name);
    }
});

Multiple Forms or Multiple Submits in a Page?

Best practice: one form per product is definitely the way to go.

Benefits:

  • It will save you the hassle of having to parse the data to figure out which product was clicked
  • It will reduce the size of data being posted

In your specific situation

If you only ever intend to have one form element, in this case a submit button, one form for all should work just fine.


My recommendation Do one form per product, and change your markup to something like:

<form method="post" action="">
    <input type="hidden" name="product_id" value="123">
    <button type="submit" name="action" value="add_to_cart">Add to Cart</button>
</form>

This will give you a much cleaner and usable POST. No parsing. And it will allow you to add more parameters in the future (size, color, quantity, etc).

Note: There's no technical benefit to using <button> vs. <input>, but as a programmer I find it cooler to work with action=='add_to_cart' than action=='Add to Cart'. Besides, I hate mixing presentation with logic. If one day you decide that it makes more sense for the button to say "Add" or if you want to use different languages, you could do so freely without having to worry about your back-end code.

Setting an environment variable before a command in Bash is not working for the second command in a pipe

Use a shell script:

#!/bin/bash
# myscript
FOO=bar
somecommand someargs | somecommand2

> ./myscript

Python: json.loads returns items prefixing with 'u'

The d3 print below is the one you are looking for (which is the combination of dumps and loads) :)

Having:

import json

d = """{"Aa": 1, "BB": "blabla", "cc": "False"}"""

d1 = json.loads(d)              # Produces a dictionary out of the given string
d2 = json.dumps(d)              # Produces a string out of a given dict or string
d3 = json.dumps(json.loads(d))  # 'dumps' gets the dict from 'loads' this time

print "d1:  " + str(d1)
print "d2:  " + d2
print "d3:  " + d3

Prints:

d1:  {u'Aa': 1, u'cc': u'False', u'BB': u'blabla'}
d2:  "{\"Aa\": 1, \"BB\": \"blabla\", \"cc\": \"False\"}"
d3:  {"Aa": 1, "cc": "False", "BB": "blabla"}

What are the options for (keyup) in Angular2?

I was searching for a way to bind to multiple key events - specifically, Shift+Enter - but couldn't find any good resources online. But after logging the keydown binding

<textarea (keydown)=onKeydownEvent($event)></textarea>

I discovered that the keyboard event provided all of the information I needed to detect Shift+Enter. Turns out that $event returns a fairly detailed KeyboardEvent.

onKeydownEvent(event: KeyboardEvent): void {
   if (event.keyCode === 13 && event.shiftKey) {
       // On 'Shift+Enter' do this...
   }
}

There also flags for the CtrlKey, AltKey, and MetaKey (i.e. Command key on Mac).

No need for the KeyEventsPlugin, JQuery, or a pure JS binding.

NPM clean modules

In a word no.

In two, not yet.

There is, however, an open issue for a --no-build flag to npm install to perform an installation without building, which could be used to do what you're asking.

See this open issue.

Repeat String - Javascript

Use Array(N+1).join("string_to_repeat")

SQL Server returns error "Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON'." in Windows application

FWIW, in our case a (PHP) website running on IIS was showing this message on attempting to connect to a database.

The resolution was to edit the Anonymous Authentication on that website to use the Application pool identity (and we set the application pool entry up to use a service account designed for that website).

jquery - check length of input field?

If you mean that you want to enable the submit after the user has typed at least one character, then you need to attach a key event that will check it for you.

Something like:

$("#fbss").keypress(function() {
    if($(this).val().length > 1) {
         // Enable submit button
    } else {
         // Disable submit button
    }
});

How to get the unix timestamp in C#

As of .NET 4.6, there is DateTimeOffset.ToUnixTimeSeconds.


This is an instance method, so you are expected to call it on an instance of DateTimeOffset. You can also cast any instance of DateTime, though beware the timezone. To get the current timestamp:

DateTimeOffset.Now.ToUnixTimeSeconds()

To get the timestamp from a DateTime:

DateTime foo = DateTime.Now;
long unixTime = ((DateTimeOffset)foo).ToUnixTimeSeconds();

How to get a path to a resource in a Java JAR file

Inside your ressources folder (java/main/resources) of your jar add your file (we assume that you have added an xml file named imports.xml), after that you inject ResourceLoader if you use spring like bellow

@Autowired
private ResourceLoader resourceLoader;

inside tour function write the bellow code in order to load file:

    Resource resource = resourceLoader.getResource("classpath:imports.xml");
    try{
        File file;
        file = resource.getFile();//will load the file
...
    }catch(IOException e){e.printStackTrace();}

How to run a single RSpec test?

For model, it will run case on line number 5 only

bundle exec rspec spec/models/user_spec.rb:5

For controller : it will run case on line number 5 only

bundle exec rspec spec/controllers/users_controller_spec.rb:5

For signal model or controller remove line number from above

To run case on all models

bundle exec rspec spec/models

To run case on all controller

bundle exec rspec spec/controllers

To run all cases

 bundle exec rspec 

Equivalent of LIMIT and OFFSET for SQL Server?

The equivalent of LIMIT is SET ROWCOUNT, but if you want generic pagination it's better to write a query like this:

;WITH Results_CTE AS
(
    SELECT
        Col1, Col2, ...,
        ROW_NUMBER() OVER (ORDER BY SortCol1, SortCol2, ...) AS RowNum
    FROM Table
    WHERE <whatever>
)
SELECT *
FROM Results_CTE
WHERE RowNum >= @Offset
AND RowNum < @Offset + @Limit

The advantage here is the parameterization of the offset and limit in case you decide to change your paging options (or allow the user to do so).

Note: the @Offset parameter should use one-based indexing for this rather than the normal zero-based indexing.

IOError: [Errno 2] No such file or directory trying to open a file

I got this error and fixed by appending the directory path in the loop. script not in the same directory as the files. dr1 ="~/test" directory variable

 fileop=open(dr1+"/"+fil,"r")

How do I get the collection of Model State Errors in ASP.NET MVC?

Here is the VB.

Dim validationErrors As String = String.Join(",", ModelState.Values.Where(Function(E) E.Errors.Count > 0).SelectMany(Function(E) E.Errors).[Select](Function(E) E.ErrorMessage).ToArray())

List View Filter Android

Add an EditText on top of your listview in its .xml layout file. And in your activity/fragment..

lv = (ListView) findViewById(R.id.list_view);
    inputSearch = (EditText) findViewById(R.id.inputSearch);

// Adding items to listview
adapter = new ArrayAdapter<String>(this, R.layout.list_item, R.id.product_name,    products);
lv.setAdapter(adapter);       
inputSearch.addTextChangedListener(new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence cs, int arg1, int arg2, int arg3) {
        // When user changed the Text
        MainActivity.this.adapter.getFilter().filter(cs);
    }

    @Override
    public void beforeTextChanged(CharSequence arg0, int arg1, int arg2, int arg3) { }

    @Override
    public void afterTextChanged(Editable arg0) {}
});

The basic here is to add an OnTextChangeListener to your edit text and inside its callback method apply filter to your listview's adapter.

EDIT

To get filter to your custom BaseAdapter you"ll need to implement Filterable interface.

class CustomAdapter extends BaseAdapter implements Filterable {

    public View getView(){
    ...
    }
    public Integer getCount()
    {
    ...
    }

    @Override
    public Filter getFilter() {

        Filter filter = new Filter() {

            @SuppressWarnings("unchecked")
            @Override
            protected void publishResults(CharSequence constraint, FilterResults results) {

                arrayListNames = (List<String>) results.values;
                notifyDataSetChanged();
            }

            @Override
            protected FilterResults performFiltering(CharSequence constraint) {

                FilterResults results = new FilterResults();
                ArrayList<String> FilteredArrayNames = new ArrayList<String>();

                // perform your search here using the searchConstraint String.

                constraint = constraint.toString().toLowerCase();
                for (int i = 0; i < mDatabaseOfNames.size(); i++) {
                    String dataNames = mDatabaseOfNames.get(i);
                    if (dataNames.toLowerCase().startsWith(constraint.toString()))  {
                        FilteredArrayNames.add(dataNames);
                    }
                }

                results.count = FilteredArrayNames.size();
                results.values = FilteredArrayNames;
                Log.e("VALUES", results.values.toString());

                return results;
            }
        };

        return filter;
    }
}

Inside performFiltering() you need to do actual comparison of the search query to values in your database. It will pass its result to publishResults() method.

Getting the base url of the website and globally passing it to twig in Symfony 2

Instead of passing variable to template globally, you can define a base template and render the 'global part' in it. The base template can be inherited.

Example of rendering template From the symfony Documentation:

<div id="sidebar">
  {% render "AcmeArticleBundle:Article:recentArticles" with {'max': 3} %}
</div>

Highlight a word with jQuery

You need to get the content of the p tag and replace all the dolors in it with the highlighted version.

You don't even need to have jQuery for this. :-)

TypeError : Unhashable type

A list is unhashable because its contents can change over its lifetime. You can update an item contained in the list at any time.

A list doesn't use a hash for indexing, so it isn't restricted to hashable items.

Android ImageView setImageResource in code

you use that code

ImageView[] ivCard = new ImageView[1];

@override    
protected void onCreate(Bundle savedInstanceState)  

ivCard[0]=(ImageView)findViewById(R.id.imageView1);

What does LINQ return when the results are empty

Other posts here have made it clear that the result is an "empty" IQueryable, which ToList() will correctly change to be an empty list etc.

Do be careful with some of the operators, as they will throw if you send them an empty enumerable. This can happen when you chain them together.

IIS: Idle Timeout vs Recycle

IIS now has

Idle Time-out Action : Suspend setting

Suspending is just freezes the process and it is much more efficient than the destroying the process.

How to bundle vendor scripts separately and require them as needed with Webpack?

I am not sure if I fully understand your problem but since I had similar issue recently I will try to help you out.

Vendor bundle.

You should use CommonsChunkPlugin for that. in the configuration you specify the name of the chunk (e.g. vendor), and file name that will be generated (vendor.js).

new webpack.optimize.CommonsChunkPlugin("vendor", "vendor.js", Infinity),

Now important part, you have to now specify what does it mean vendor library and you do that in an entry section. One one more item to entry list with the same name as the name of the newly declared chunk (i.e. 'vendor' in this case). The value of that entry should be the list of all the modules that you want to move to vendor bundle. in your case it should look something like:

entry: {
    app: 'entry.js',
    vendor: ['jquery', 'jquery.plugin1']
}

JQuery as global

Had the same problem and solved it with ProvidePlugin. here you are not defining global object but kind of shurtcuts to modules. i.e. you can configure it like that:

new webpack.ProvidePlugin({
    $: "jquery"
})

And now you can just use $ anywhere in your code - webpack will automatically convert that to

require('jquery')

I hope it helped. you can also look at my webpack configuration file that is here

I love webpack, but I agree that the documentation is not the nicest one in the world... but hey.. people were saying same thing about Angular documentation in the begining :)


Edit:

To have entrypoint-specific vendor chunks just use CommonsChunkPlugins multiple times:

new webpack.optimize.CommonsChunkPlugin("vendor-page1", "vendor-page1.js", Infinity),
new webpack.optimize.CommonsChunkPlugin("vendor-page2", "vendor-page2.js", Infinity),

and then declare different extenral libraries for different files:

entry: {
    page1: ['entry.js'],
    page2: ['entry2.js'],
    "vendor-page1": [
        'lodash'
    ],
    "vendor-page2": [
        'jquery'
    ]
},

If some libraries are overlapping (and for most of them) between entry points then you can extract them to common file using same plugin just with different configuration. See this example.

How do I use raw_input in Python 3

Probably not the best solution, but before I came here I just made this on the fly to keep working without having a quick break from study.

def raw_input(x):
  input(x)

Then when I run raw_input('Enter your first name: ') on the script I was working on, it captures it as does input() would.

There may be a reason not to do this, that I haven't come across yet!

Do you (really) write exception safe code?

Your question makes an assertion, that "Writing exception-safe code is very hard". I will answer your questions first, and then, answer the hidden question behind them.

Answering questions

Do you really write exception safe code?

Of course, I do.

This is the reason Java lost a lot of its appeal to me as a C++ programmer (lack of RAII semantics), but I am digressing: This is a C++ question.

It is, in fact, necessary when you need to work with STL or Boost code. For example, C++ threads (boost::thread or std::thread) will throw an exception to exit gracefully.

Are you sure your last "production ready" code is exception safe?

Can you even be sure, that it is?

Writing exception-safe code is like writing bug-free code.

You can't be 100% sure your code is exception safe. But then, you strive for it, using well-known patterns, and avoiding well-known anti-patterns.

Do you know and/or actually use alternatives that work?

There are no viable alternatives in C++ (i.e. you'll need to revert back to C and avoid C++ libraries, as well as external surprises like Windows SEH).

Writing exception safe code

To write exception safe code, you must know first what level of exception safety each instruction you write is.

For example, a new can throw an exception, but assigning a built-in (e.g. an int, or a pointer) won't fail. A swap will never fail (don't ever write a throwing swap), a std::list::push_back can throw...

Exception guarantee

The first thing to understand is that you must be able to evaluate the exception guarantee offered by all of your functions:

  1. none: Your code should never offer that. This code will leak everything, and break down at the very first exception thrown.
  2. basic: This is the guarantee you must at the very least offer, that is, if an exception is thrown, no resources are leaked, and all objects are still whole
  3. strong: The processing will either succeed, or throw an exception, but if it throws, then the data will be in the same state as if the processing had not started at all (this gives a transactional power to C++)
  4. nothrow/nofail: The processing will succeed.

Example of code

The following code seems like correct C++, but in truth, offers the "none" guarantee, and thus, it is not correct:

void doSomething(T & t)
{
   if(std::numeric_limits<int>::max() > t.integer)  // 1.   nothrow/nofail
      t.integer += 1 ;                              // 1'.  nothrow/nofail
   X * x = new X() ;                // 2. basic : can throw with new and X constructor
   t.list.push_back(x) ;            // 3. strong : can throw
   x->doSomethingThatCanThrow() ;   // 4. basic : can throw
}

I write all my code with this kind of analysis in mind.

The lowest guarantee offered is basic, but then, the ordering of each instruction makes the whole function "none", because if 3. throws, x will leak.

The first thing to do would be to make the function "basic", that is putting x in a smart pointer until it is safely owned by the list:

void doSomething(T & t)
{
   if(std::numeric_limits<int>::max() > t.integer)  // 1.   nothrow/nofail
      t.integer += 1 ;                              // 1'.  nothrow/nofail
   std::auto_ptr<X> x(new X()) ;    // 2.  basic : can throw with new and X constructor
   X * px = x.get() ;               // 2'. nothrow/nofail
   t.list.push_back(px) ;           // 3.  strong : can throw
   x.release() ;                    // 3'. nothrow/nofail
   px->doSomethingThatCanThrow() ;  // 4.  basic : can throw
}

Now, our code offers a "basic" guarantee. Nothing will leak, and all objects will be in a correct state. But we could offer more, that is, the strong guarantee. This is where it can become costly, and this is why not all C++ code is strong. Let's try it:

void doSomething(T & t)
{
   // we create "x"
   std::auto_ptr<X> x(new X()) ;    // 1. basic : can throw with new and X constructor
   X * px = x.get() ;               // 2. nothrow/nofail
   px->doSomethingThatCanThrow() ;  // 3. basic : can throw

   // we copy the original container to avoid changing it
   T t2(t) ;                        // 4. strong : can throw with T copy-constructor

   // we put "x" in the copied container
   t2.list.push_back(px) ;          // 5. strong : can throw
   x.release() ;                    // 6. nothrow/nofail
   if(std::numeric_limits<int>::max() > t2.integer)  // 7.   nothrow/nofail
      t2.integer += 1 ;                              // 7'.  nothrow/nofail

   // we swap both containers
   t.swap(t2) ;                     // 8. nothrow/nofail
}

We re-ordered the operations, first creating and setting X to its right value. If any operation fails, then t is not modified, so, operation 1 to 3 can be considered "strong": If something throws, t is not modified, and X will not leak because it's owned by the smart pointer.

Then, we create a copy t2 of t, and work on this copy from operation 4 to 7. If something throws, t2 is modified, but then, t is still the original. We still offer the strong guarantee.

Then, we swap t and t2. Swap operations should be nothrow in C++, so let's hope the swap you wrote for T is nothrow (if it isn't, rewrite it so it is nothrow).

So, if we reach the end of the function, everything succeeded (No need of a return type) and t has its excepted value. If it fails, then t has still its original value.

Now, offering the strong guarantee could be quite costly, so don't strive to offer the strong guarantee to all your code, but if you can do it without a cost (and C++ inlining and other optimization could make all the code above costless), then do it. The function user will thank you for it.

Conclusion

It takes some habit to write exception-safe code. You'll need to evaluate the guarantee offered by each instruction you'll use, and then, you'll need to evaluate the guarantee offered by a list of instructions.

Of course, the C++ compiler won't back up the guarantee (in my code, I offer the guarantee as a @warning doxygen tag), which is kinda sad, but it should not stop you from trying to write exception-safe code.

Normal failure vs. bug

How can a programmer guarantee that a no-fail function will always succeed? After all, the function could have a bug.

This is true. The exception guarantees are supposed to be offered by bug-free code. But then, in any language, calling a function supposes the function is bug-free. No sane code protects itself against the possibility of it having a bug. Write code the best you can, and then, offer the guarantee with the supposition it is bug-free. And if there is a bug, correct it.

Exceptions are for exceptional processing failure, not for code bugs.

Last words

Now, the question is "Is this worth it ?".

Of course, it is. Having a "nothrow/no-fail" function knowing that the function won't fail is a great boon. The same can be said for a "strong" function, which enables you to write code with transactional semantics, like databases, with commit/rollback features, the commit being the normal execution of the code, throwing exceptions being the rollback.

Then, the "basic" is the very least guarantee you should offer. C++ is a very strong language there, with its scopes, enabling you to avoid any resource leaks (something a garbage collector would find it difficult to offer for the database, connection or file handles).

So, as far as I see it, it is worth it.

Edit 2010-01-29: About non-throwing swap

nobar made a comment that I believe, is quite relevant, because it is part of "how do you write exception safe code":

  • [me] A swap will never fail (don't even write a throwing swap)
  • [nobar] This is a good recommendation for custom-written swap() functions. It should be noted, however, that std::swap() can fail based on the operations that it uses internally

the default std::swap will make copies and assignments, which, for some objects, can throw. Thus, the default swap could throw, either used for your classes or even for STL classes. As far as the C++ standard is concerned, the swap operation for vector, deque, and list won't throw, whereas it could for map if the comparison functor can throw on copy construction (See The C++ Programming Language, Special Edition, appendix E, E.4.3.Swap).

Looking at Visual C++ 2008 implementation of the vector's swap, the vector's swap won't throw if the two vectors have the same allocator (i.e., the normal case), but will make copies if they have different allocators. And thus, I assume it could throw in this last case.

So, the original text still holds: Don't ever write a throwing swap, but nobar's comment must be remembered: Be sure the objects you're swapping have a non-throwing swap.

Edit 2011-11-06: Interesting article

Dave Abrahams, who gave us the basic/strong/nothrow guarantees, described in an article his experience about making the STL exception safe:

http://www.boost.org/community/exception_safety.html

Look at the 7th point (Automated testing for exception-safety), where he relies on automated unit testing to make sure every case is tested. I guess this part is an excellent answer to the question author's "Can you even be sure, that it is?".

Edit 2013-05-31: Comment from dionadar

t.integer += 1; is without the guarantee that overflow will not happen NOT exception safe, and in fact may technically invoke UB! (Signed overflow is UB: C++11 5/4 "If during the evaluation of an expression, the result is not mathematically defined or not in the range of representable values for its type, the behavior is undefined.") Note that unsigned integer do not overflow, but do their computations in an equivalence class modulo 2^#bits.

Dionadar is referring to the following line, which indeed has undefined behaviour.

   t.integer += 1 ;                 // 1. nothrow/nofail

The solution here is to verify if the integer is already at its max value (using std::numeric_limits<T>::max()) before doing the addition.

My error would go in the "Normal failure vs. bug" section, that is, a bug. It doesn't invalidate the reasoning, and it does not mean the exception-safe code is useless because impossible to attain. You can't protect yourself against the computer switching off, or compiler bugs, or even your bugs, or other errors. You can't attain perfection, but you can try to get as near as possible.

I corrected the code with Dionadar's comment in mind.

How to print binary tree diagram?

Here is another way to visualize your tree: save the nodes as an xml file and then let your browser show you the hierarchy:

class treeNode{
    int key;
    treeNode left;
    treeNode right;

    public treeNode(int key){
        this.key = key;
        left = right = null;
    }

    public void printNode(StringBuilder output, String dir){
        output.append("<node key='" + key + "' dir='" + dir + "'>");
        if(left != null)
            left.printNode(output, "l");
        if(right != null)
            right.printNode(output, "r");
        output.append("</node>");
    }
}

class tree{
    private treeNode treeRoot;

    public tree(int key){
        treeRoot = new treeNode(key);
    }

    public void insert(int key){
        insert(treeRoot, key);
    }

    private treeNode insert(treeNode root, int key){
        if(root == null){
            treeNode child = new treeNode(key);
            return child;
        }

        if(key < root.key)
            root.left = insert(root.left, key);
        else if(key > root.key)
            root.right = insert(root.right, key);

        return root;
    }

    public void saveTreeAsXml(){
        StringBuilder strOutput = new StringBuilder();
        strOutput.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
        treeRoot.printNode(strOutput, "root");
        try {
            PrintWriter writer = new PrintWriter("C:/tree.xml", "UTF-8");
            writer.write(strOutput.toString());
            writer.close();
        }
        catch (FileNotFoundException e){

        }
        catch(UnsupportedEncodingException e){

        }
    }
}

Here is code to test it:

    tree t = new tree(1);
    t.insert(10);
    t.insert(5);
    t.insert(4);
    t.insert(20);
    t.insert(40);
    t.insert(30);
    t.insert(80);
    t.insert(60);
    t.insert(50);

    t.saveTreeAsXml();

And the output looks like this:

enter image description here

How to set a variable to be "Today's" date in Python/Pandas

pd.datetime.now().strftime("%d/%m/%Y")

this will give output as '11/02/2019'

you can use add time if you want

pd.datetime.now().strftime("%d/%m/%Y %I:%M:%S")

this will give output as '11/02/2019 11:08:26'

strftime formats

UPDATE if exists else INSERT in SQL Server 2008

Many people will suggest you use MERGE, but I caution you against it. By default, it doesn't protect you from concurrency and race conditions any more than multiple statements, but it does introduce other dangers:

http://www.mssqltips.com/sqlservertip/3074/use-caution-with-sql-servers-merge-statement/

Even with this "simpler" syntax available, I still prefer this approach (error handling omitted for brevity):

SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
BEGIN TRANSACTION;
UPDATE dbo.table SET ... WHERE PK = @PK;
IF @@ROWCOUNT = 0
BEGIN
  INSERT dbo.table(PK, ...) SELECT @PK, ...;
END
COMMIT TRANSACTION;

A lot of folks will suggest this way:

SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
BEGIN TRANSACTION;
IF EXISTS (SELECT 1 FROM dbo.table WHERE PK = @PK)
BEGIN
  UPDATE ...
END
ELSE
BEGIN
  INSERT ...
END
COMMIT TRANSACTION;

But all this accomplishes is ensuring you may need to read the table twice to locate the row(s) to be updated. In the first sample, you will only ever need to locate the row(s) once. (In both cases, if no rows are found from the initial read, an insert occurs.)

Others will suggest this way:

BEGIN TRY
  INSERT ...
END TRY
BEGIN CATCH
  IF ERROR_NUMBER() = 2627
    UPDATE ...
END CATCH

However, this is problematic if for no other reason than letting SQL Server catch exceptions that you could have prevented in the first place is much more expensive, except in the rare scenario where almost every insert fails. I prove as much here:

Not sure what you think you gain by having a single statement; I don't think you gain anything. MERGE is a single statement but it still has to really perform multiple operations anyway - even though it makes you think it doesn't.

java.text.ParseException: Unparseable date

Pattern is wrong

    String date="Sat Jun 01 12:53:10 IST 2013";
    SimpleDateFormat sdf=new SimpleDateFormat("E MMM dd hh:mm:ss Z yyyy");
    Date currentdate;
    currentdate=sdf.parse(date);
    System.out.println(currentdate);

How can I wait In Node.js (JavaScript)? l need to pause for a period of time

function doThen(conditional,then,timer) {
    var timer = timer || 1;
    var interval = setInterval(function(){
        if(conditional()) {
            clearInterval(interval);
            then();
        }
    }, timer);
}

Example usage:

var counter = 1;
doThen(
    function() {
        counter++;
        return counter == 1000;
    },
    function() {
        console.log("Counter hit 1000"); // 1000 repeats later
    }
)

Using a scanner to accept String input and storing in a String Array

There is no use of pointers in java so far. You can create an object from the class and use different classes which are linked with each other and use the functions of every class in main class.

Read/Write String from/to a File in Android

check the below code.

Reading from a file in the filesystem.

FileInputStream fis = null;
    try {

        fis = context.openFileInput(fileName);
        InputStreamReader isr = new InputStreamReader(fis);
        // READ STRING OF UNKNOWN LENGTH
        StringBuilder sb = new StringBuilder();
        char[] inputBuffer = new char[2048];
        int l;
        // FILL BUFFER WITH DATA
        while ((l = isr.read(inputBuffer)) != -1) {
            sb.append(inputBuffer, 0, l);
        }
        // CONVERT BYTES TO STRING
        String readString = sb.toString();
        fis.close();

    catch (Exception e) {

    } finally {
        if (fis != null) {
            fis = null;
        }
    }

below code is to write the file in to internal filesystem.

FileOutputStream fos = null;
    try {

        fos = context.openFileOutput(fileName, Context.MODE_PRIVATE);
        fos.write(stringdatatobestoredinfile.getBytes());
        fos.flush();
        fos.close();

    } catch (Exception e) {

    } finally {
        if (fos != null) {
            fos = null;
        }
    }

I think this will help you.

Vim delete blank lines

This worked for me:

:%s/^[^a-zA-Z0-9]$\n//ig

It basically deletes all the lines that don't have a number or letter. Since all the items in my list had letters, it deleted all the blank lines.

Eloquent - where not equal to

Or like this:

Code::whereNotIn('to_be_used_by_user_id', [2])->get();

YouTube iframe API: how do I control an iframe player that's already in the HTML?

Fiddle Links: Source code - Preview - Small version
Update: This small function will only execute code in a single direction. If you want full support (eg event listeners / getters), have a look at Listening for Youtube Event in jQuery

As a result of a deep code analysis, I've created a function: function callPlayer requests a function call on any framed YouTube video. See the YouTube Api reference to get a full list of possible function calls. Read the comments at the source code for an explanation.

On 17 may 2012, the code size was doubled in order to take care of the player's ready state. If you need a compact function which does not deal with the player's ready state, see http://jsfiddle.net/8R5y6/.

/**
 * @author       Rob W <[email protected]>
 * @website      https://stackoverflow.com/a/7513356/938089
 * @version      20190409
 * @description  Executes function on a framed YouTube video (see website link)
 *               For a full list of possible functions, see:
 *               https://developers.google.com/youtube/js_api_reference
 * @param String frame_id The id of (the div containing) the frame
 * @param String func     Desired function to call, eg. "playVideo"
 *        (Function)      Function to call when the player is ready.
 * @param Array  args     (optional) List of arguments to pass to function func*/
function callPlayer(frame_id, func, args) {
    if (window.jQuery && frame_id instanceof jQuery) frame_id = frame_id.get(0).id;
    var iframe = document.getElementById(frame_id);
    if (iframe && iframe.tagName.toUpperCase() != 'IFRAME') {
        iframe = iframe.getElementsByTagName('iframe')[0];
    }

    // When the player is not ready yet, add the event to a queue
    // Each frame_id is associated with an own queue.
    // Each queue has three possible states:
    //  undefined = uninitialised / array = queue / .ready=true = ready
    if (!callPlayer.queue) callPlayer.queue = {};
    var queue = callPlayer.queue[frame_id],
        domReady = document.readyState == 'complete';

    if (domReady && !iframe) {
        // DOM is ready and iframe does not exist. Log a message
        window.console && console.log('callPlayer: Frame not found; id=' + frame_id);
        if (queue) clearInterval(queue.poller);
    } else if (func === 'listening') {
        // Sending the "listener" message to the frame, to request status updates
        if (iframe && iframe.contentWindow) {
            func = '{"event":"listening","id":' + JSON.stringify(''+frame_id) + '}';
            iframe.contentWindow.postMessage(func, '*');
        }
    } else if ((!queue || !queue.ready) && (
               !domReady ||
               iframe && !iframe.contentWindow ||
               typeof func === 'function')) {
        if (!queue) queue = callPlayer.queue[frame_id] = [];
        queue.push([func, args]);
        if (!('poller' in queue)) {
            // keep polling until the document and frame is ready
            queue.poller = setInterval(function() {
                callPlayer(frame_id, 'listening');
            }, 250);
            // Add a global "message" event listener, to catch status updates:
            messageEvent(1, function runOnceReady(e) {
                if (!iframe) {
                    iframe = document.getElementById(frame_id);
                    if (!iframe) return;
                    if (iframe.tagName.toUpperCase() != 'IFRAME') {
                        iframe = iframe.getElementsByTagName('iframe')[0];
                        if (!iframe) return;
                    }
                }
                if (e.source === iframe.contentWindow) {
                    // Assume that the player is ready if we receive a
                    // message from the iframe
                    clearInterval(queue.poller);
                    queue.ready = true;
                    messageEvent(0, runOnceReady);
                    // .. and release the queue:
                    while (tmp = queue.shift()) {
                        callPlayer(frame_id, tmp[0], tmp[1]);
                    }
                }
            }, false);
        }
    } else if (iframe && iframe.contentWindow) {
        // When a function is supplied, just call it (like "onYouTubePlayerReady")
        if (func.call) return func();
        // Frame exists, send message
        iframe.contentWindow.postMessage(JSON.stringify({
            "event": "command",
            "func": func,
            "args": args || [],
            "id": frame_id
        }), "*");
    }
    /* IE8 does not support addEventListener... */
    function messageEvent(add, listener) {
        var w3 = add ? window.addEventListener : window.removeEventListener;
        w3 ?
            w3('message', listener, !1)
        :
            (add ? window.attachEvent : window.detachEvent)('onmessage', listener);
    }
}

Usage:

callPlayer("whateverID", function() {
    // This function runs once the player is ready ("onYouTubePlayerReady")
    callPlayer("whateverID", "playVideo");
});
// When the player is not ready yet, the function will be queued.
// When the iframe cannot be found, a message is logged in the console.
callPlayer("whateverID", "playVideo");

Possible questions (& answers):

Q: It doesn't work!
A: "Doesn't work" is not a clear description. Do you get any error messages? Please show the relevant code.

Q: playVideo does not play the video.
A: Playback requires user interaction, and the presence of allow="autoplay" on the iframe. See https://developers.google.com/web/updates/2017/09/autoplay-policy-changes and https://developer.mozilla.org/en-US/docs/Web/Media/Autoplay_guide

Q: I have embedded a YouTube video using <iframe src="http://www.youtube.com/embed/As2rZGPGKDY" />but the function doesn't execute any function!
A: You have to add ?enablejsapi=1 at the end of your URL: /embed/vid_id?enablejsapi=1.

Q: I get error message "An invalid or illegal string was specified". Why?
A: The API doesn't function properly at a local host (file://). Host your (test) page online, or use JSFiddle. Examples: See the links at the top of this answer.

Q: How did you know this?
A: I have spent some time to manually interpret the API's source. I concluded that I had to use the postMessage method. To know which arguments to pass, I created a Chrome extension which intercepts messages. The source code for the extension can be downloaded here.

Q: What browsers are supported?
A: Every browser which supports JSON and postMessage.

  • IE 8+
  • Firefox 3.6+ (actually 3.5, but document.readyState was implemented in 3.6)
  • Opera 10.50+
  • Safari 4+
  • Chrome 3+

Related answer / implementation: Fade-in a framed video using jQuery
Full API support: Listening for Youtube Event in jQuery
Official API: https://developers.google.com/youtube/iframe_api_reference

Revision history

  • 17 may 2012
    Implemented onYouTubePlayerReady: callPlayer('frame_id', function() { ... }).
    Functions are automatically queued when the player is not ready yet.
  • 24 july 2012
    Updated and successully tested in the supported browsers (look ahead).
  • 10 october 2013 When a function is passed as an argument, callPlayer forces a check of readiness. This is needed, because when callPlayer is called right after the insertion of the iframe while the document is ready, it can't know for sure that the iframe is fully ready. In Internet Explorer and Firefox, this scenario resulted in a too early invocation of postMessage, which was ignored.
  • 12 Dec 2013, recommended to add &origin=* in the URL.
  • 2 Mar 2014, retracted recommendation to remove &origin=* to the URL.
  • 9 april 2019, fix bug that resulted in infinite recursion when YouTube loads before the page was ready. Add note about autoplay.

Pipe to/from the clipboard in Bash script

There's a wealth of clipboards you could be dealing with. I expect you're probably a Linux user who wants to put stuff in the X Windows primary clipboard. Usually, the clipboard you want to talk to has a utility that lets you talk to it.

In the case of X, there's xclip (and others). xclip -selection c will send data to the clipboard that works with Ctrl + C, Ctrl + V in most applications.

If you're on Mac OS X, there's pbcopy. e.g cat example.txt | pbcopy

If you're in Linux terminal mode (no X) then look into gpm or screen which has a clipboard. Try the screen command readreg.

Under Windows 10+ or cygwin, use /dev/clipboard or clip.

The VMware Authorization Service is not running

Run as admin - vmware workstation will do.

RecyclerView and java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter positionViewHolder in Samsung devices

This is an example for refreshing data with completely new content. You can easily modify it to fit your needs. I solved this in my case by calling:

notifyItemRangeRemoved(0, previousContentSize);

before:

notifyItemRangeInserted(0, newContentSize);

This is the correct solution and is also mentioned in this post by an AOSP project member.

How to fix UITableView separator on iOS 7?

This is default by iOS7 design. try to do the below:

[tableView setSeparatorInset:UIEdgeInsetsMake(0, 0, 0, 0)];

You can set the 'Separator Inset' from the storyboard:

enter image description here

enter image description here

What is a simple C or C++ TCP server and client example?

Although many year ago, clsocket seems a really nice small cross-platform (Windows, Linux, Mac OSX): https://github.com/DFHack/clsocket

Xcode 6.1 - How to uninstall command line tools?

If you installed the command line tools separately, delete them using:

sudo rm -rf /Library/Developer/CommandLineTools

Material Design not styling alert dialogs

For some reason the android:textColor only seems to update the title color. You can change the message text color by using a

SpannableString.AlertDialog.Builder builder = new AlertDialog.Builder(new ContextThemeWrapper(this, R.style.MyDialogTheme));

AlertDialog dialog = builder.create();
                Spannable wordtoSpan = new SpannableString("I know just how to whisper, And I know just how to cry,I know just where to find the answers");
                wordtoSpan.setSpan(new ForegroundColorSpan(Color.BLUE), 15, 30, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
                dialog.setMessage(wordtoSpan);
                dialog.show();

Use Awk to extract substring

I am asking in general, how to write a compatible awk script that performs the same functionality ...

To solve the problem in your quesiton is easy. (check others' answer).

If you want to write an awk script, which portable to any awk implementations and versions (gawk/nawk/mawk...) it is really hard, even if with --posix (gawk)

for example:

  • some awk works on string in terms of characters, some with bytes
  • some supports \x escape, some not
  • FS interpreter works differently
  • keywords/reserved words abbreviation restriction
  • some operator restriction e.g. **
  • even same awk impl. (gawk for example), the version 4.0 and 3.x have difference too.
  • the implementation of certain functions are also different. (your problem is one example, see below)

well all the points above are just spoken in general. Back to your problem, you problem is only related to fundamental feature of awk. awk '{print $x}' the line like that will work all awks.

There are two reasons why your awk line behaves differently on gawk and mawk:

  • your used substr() function wrongly. this is the main cause. you have substr($0, 0, RSTART - 1) the 0 should be 1, no matter which awk do you use. awk array, string idx etc are 1-based.

  • gawk and mawk implemented substr() differently.

How to check a string starts with numeric number?

This should work:

String s = "123foo";
Character.isDigit(s.charAt(0));

How to represent multiple conditions in a shell if statement?

Be careful if you have spaces in your string variables and you check for existence. Be sure to quote them properly.

if [ ! "${somepath}" ] || [ ! "${otherstring}" ] || [ ! "${barstring}" ] ; then

How to update RecyclerView Adapter Data?

This is a general answer for future visitors. The various ways to update the adapter data are explained. The process includes two main steps every time:

  1. Update the data set
  2. Notify the adapter of the change

#Insert single item

Add "Pig" at index 2.

Insert single item
String item = "Pig";
int insertIndex = 2;
data.add(insertIndex, item);
adapter.notifyItemInserted(insertIndex);

#Insert multiple items

Insert three more animals at index 2.

Insert multiple items
ArrayList<String> items = new ArrayList<>();
items.add("Pig");
items.add("Chicken");
items.add("Dog");
int insertIndex = 2;
data.addAll(insertIndex, items);
adapter.notifyItemRangeInserted(insertIndex, items.size());

#Remove a single item

Remove "Pig" from the list.

Remove single item
int removeIndex = 2;
data.remove(removeIndex);
adapter.notifyItemRemoved(removeIndex);

#Remove multiple items

Remove "Camel" and "Sheep" from the list.

Remove multiple items
int startIndex = 2; // inclusive
int endIndex = 4;   // exclusive
int count = endIndex - startIndex; // 2 items will be removed
data.subList(startIndex, endIndex).clear();
adapter.notifyItemRangeRemoved(startIndex, count);

#Remove all items

Clear the whole list.

Remove all items
data.clear();
adapter.notifyDataSetChanged();

#Replace old list with the new list

Clear the old list then add a new one.

Replace old list with new list
// clear old list
data.clear();

// add new list
ArrayList<String> newList = new ArrayList<>();
newList.add("Lion");
newList.add("Wolf");
newList.add("Bear");
data.addAll(newList);

// notify adapter
adapter.notifyDataSetChanged();

The adapter has a reference to data, so it is important that I didn't set data to a new object. Instead, I cleared the old items from data and then added the new ones.

#Update single item

Change the "Sheep" item so that it says "I like sheep."

Update single item
String newValue = "I like sheep.";
int updateIndex = 3;
data.set(updateIndex, newValue);
adapter.notifyItemChanged(updateIndex);

#Move single item

Move "Sheep" from position 3 to position 1.

Move single item
int fromPosition = 3;
int toPosition = 1;

// update data array
String item = data.get(fromPosition);
data.remove(fromPosition);
data.add(toPosition, item);

// notify adapter
adapter.notifyItemMoved(fromPosition, toPosition);

#Code

Here is the project code for your reference. The RecyclerView Adapter code can be found at this answer.

MainActivity.java

public class MainActivity extends AppCompatActivity implements MyRecyclerViewAdapter.ItemClickListener {

    List<String> data;
    MyRecyclerViewAdapter adapter;

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

        // data to populate the RecyclerView with
        data = new ArrayList<>();
        data.add("Horse");
        data.add("Cow");
        data.add("Camel");
        data.add("Sheep");
        data.add("Goat");

        // set up the RecyclerView
        RecyclerView recyclerView = findViewById(R.id.rvAnimals);
        LinearLayoutManager layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        DividerItemDecoration dividerItemDecoration = new DividerItemDecoration(recyclerView.getContext(),
                layoutManager.getOrientation());
        recyclerView.addItemDecoration(dividerItemDecoration);
        adapter = new MyRecyclerViewAdapter(this, data);
        adapter.setClickListener(this);
        recyclerView.setAdapter(adapter);
    }

    @Override
    public void onItemClick(View view, int position) {
        Toast.makeText(this, "You clicked " + adapter.getItem(position) + " on row number " + position, Toast.LENGTH_SHORT).show();
    }

    public void onButtonClick(View view) {
        insertSingleItem();
    }

    private void insertSingleItem() {
        String item = "Pig";
        int insertIndex = 2;
        data.add(insertIndex, item);
        adapter.notifyItemInserted(insertIndex);
    }

    private void insertMultipleItems() {
        ArrayList<String> items = new ArrayList<>();
        items.add("Pig");
        items.add("Chicken");
        items.add("Dog");
        int insertIndex = 2;
        data.addAll(insertIndex, items);
        adapter.notifyItemRangeInserted(insertIndex, items.size());
    }

    private void removeSingleItem() {
        int removeIndex = 2;
        data.remove(removeIndex);
        adapter.notifyItemRemoved(removeIndex);
    }

    private void removeMultipleItems() {
        int startIndex = 2; // inclusive
        int endIndex = 4;   // exclusive
        int count = endIndex - startIndex; // 2 items will be removed
        data.subList(startIndex, endIndex).clear();
        adapter.notifyItemRangeRemoved(startIndex, count);
    }

    private void removeAllItems() {
        data.clear();
        adapter.notifyDataSetChanged();
    }

    private void replaceOldListWithNewList() {
        // clear old list
        data.clear();

        // add new list
        ArrayList<String> newList = new ArrayList<>();
        newList.add("Lion");
        newList.add("Wolf");
        newList.add("Bear");
        data.addAll(newList);

        // notify adapter
        adapter.notifyDataSetChanged();
    }

    private void updateSingleItem() {
        String newValue = "I like sheep.";
        int updateIndex = 3;
        data.set(updateIndex, newValue);
        adapter.notifyItemChanged(updateIndex);
    }

    private void moveSingleItem() {
        int fromPosition = 3;
        int toPosition = 1;

        // update data array
        String item = data.get(fromPosition);
        data.remove(fromPosition);
        data.add(toPosition, item);

        // notify adapter
        adapter.notifyItemMoved(fromPosition, toPosition);
    }
}

#Notes

  • If you use notifyDataSetChanged(), then no animation will be performed. This can also be an expensive operation, so it is not recommended to use notifyDataSetChanged() if you are only updating a single item or a range of items.
  • Check out DiffUtil if you are making large or complex changes to a list.

#Further study

Linux Script to check if process is running and act on the result

I have adopted your script for my situation Jotne.

#! /bin/bash

logfile="/var/oscamlog/oscam1check.log"

case "$(pidof oscam1 | wc -w)" in

0)  echo "oscam1 not running, restarting oscam1:     $(date)" >> $logfile
    /usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1 &
    ;;
2)  echo "oscam1 running, all OK:     $(date)" >> $logfile
    ;;
*)  echo "multiple instances of oscam1 running. Stopping & restarting oscam1:     $(date)" >> $logfile
    kill $(pidof oscam1 | awk '{print $1}')
    ;;
esac

While I was testing, I ran into a problem.. I started 3 extra process's of oscam1 with this line: /usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1 which left me with 8 process for oscam1. the problem is this.. When I run the script, It only kills 2 process's at a time, so I would have to run it 3 times to get it down to 2 process..

Other than killall -9 oscam1 followed by /usr/local/bin/oscam1 -b -c /usr/local/etc/oscam1 -t /usr/local/tmp.oscam1, in *)is there any better way to killall apart from the original process? So there would be zero downtime?

Run script on mac prompt "Permission denied"

To run in the administrator mode in mac

sudo su

UIImage: Resize, then Crop

The following simple code worked for me.

[imageView setContentMode:UIViewContentModeScaleAspectFill];
[imageView setClipsToBounds:YES];

spark submit add multiple jars in classpath

You can use --jars $(echo /Path/To/Your/Jars/*.jar | tr ' ' ',') to include entire folder of Jars. So, spark-submit -- class com.yourClass \ --jars $(echo /Path/To/Your/Jars/*.jar | tr ' ' ',') \ ...

How to keep console window open

To be able to give it input without it closing as well you could enclose the code in a while loop

while (true) 
{
     <INSERT CODE HERE>
}

It will continue to halt at Console.ReadLine();, then do another loop when you input something.

Add regression line equation and R^2 on graph

Inspired by the equation style provided in this answer, a more generic approach (more than one predictor + latex output as option) can be:

print_equation= function(model, latex= FALSE, ...){
    dots <- list(...)
    cc= model$coefficients
    var_sign= as.character(sign(cc[-1]))%>%gsub("1","",.)%>%gsub("-"," - ",.)
    var_sign[var_sign==""]= ' + '

    f_args_abs= f_args= dots
    f_args$x= cc
    f_args_abs$x= abs(cc)
    cc_= do.call(format, args= f_args)
    cc_abs= do.call(format, args= f_args_abs)
    pred_vars=
        cc_abs%>%
        paste(., x_vars, sep= star)%>%
        paste(var_sign,.)%>%paste(., collapse= "")

    if(latex){
        star= " \\cdot "
        y_var= strsplit(as.character(model$call$formula), "~")[[2]]%>%
            paste0("\\hat{",.,"_{i}}")
        x_vars= names(cc_)[-1]%>%paste0(.,"_{i}")
    }else{
        star= " * "
        y_var= strsplit(as.character(model$call$formula), "~")[[2]]        
        x_vars= names(cc_)[-1]
    }

    equ= paste(y_var,"=",cc_[1],pred_vars)
    if(latex){
        equ= paste0(equ," + \\hat{\\varepsilon_{i}} \\quad where \\quad \\varepsilon \\sim \\mathcal{N}(0,",
                    summary(MetamodelKdifEryth)$sigma,")")%>%paste0("$",.,"$")
    }
    cat(equ)
}

The model argument expects an lm object, the latex argument is a boolean to ask for a simple character or a latex-formated equation, and the ... argument pass its values to the format function.

I also added an option to output it as latex so you can use this function in a rmarkdown like this:


```{r echo=FALSE, results='asis'}
print_equation(model = lm_mod, latex = TRUE)
```

Now using it:

df <- data.frame(x = c(1:100))
df$y <- 2 + 3 * df$x + rnorm(100, sd = 40)
df$z <- 8 + 3 * df$x + rnorm(100, sd = 40)
lm_mod= lm(y~x+z, data = df)

print_equation(model = lm_mod, latex = FALSE)

This code yields: y = 11.3382963933174 + 2.5893419 * x + 0.1002227 * z

And if we ask for a latex equation, rounding the parameters to 3 digits:

print_equation(model = lm_mod, latex = TRUE, digits= 3)

This yields: latex equation

How to fill DataTable with SQL Table

You can fill your data table like the below code.I am also fetching the connections at runtime using a predefined XML file that has all the connection.

  public static DataTable Execute_Query(string connection, string query)
    {
        Logger.Info("Execute Query has been called for connection " + connection);
        connection = "Data Source=" + Connections.run_singlevalue(connection, "server") + ";Initial Catalog=" + Connections.run_singlevalue(connection, "database") + ";User ID=" + Connections.run_singlevalue(connection, "username") + ";Password=" + Connections.run_singlevalue(connection, "password") + ";Connection Timeout=30;";
        DataTable dt = new DataTable();
        try
        {
            using (SqlConnection con = new SqlConnection(connection))
            {
                using (SqlCommand cmd = new SqlCommand(query, con))
                {
                    con.Open();
                    using (SqlDataAdapter da = new SqlDataAdapter(cmd))
                    {
                        da.SelectCommand.CommandTimeout = 1800;
                        da.Fill(dt);
                    }
                    con.Close();
                }
            }
            Logger.Info("Execute Query success");
            return dt;
        }
        catch (Exception ex)
        {
            Console.Write(ex.Message);
            return null;
        }
    }   

Cannot load properties file from resources directory

If it is simple application then getSystemResourceAsStream can also be used.

try (InputStream inputStream = ClassLoader.getSystemResourceAsStream("config.properties"))..

How to check for empty value in Javascript?

The counter in your for loop appears incorrect (or we're missing some code). Here's a working Fiddle.

This code:

//Where is counter[0] initialized?
for (i ; i < counter[0].value; i++)

Should be replaced with:

var timeTempCount = 5; //I'm not sure where you're getting this value so I set it.

for (var i = 0; i <= timeTempCount; i++)

Understanding Chrome network log "Stalled" state

My case is the page is sending multiple requests with different parameters when it was open. So most are being "stalled". Following requests immediately sent gets "stalled". Avoiding unnecessary requests would be better (to be lazy...).

Difference between e.target and e.currentTarget

make an example:

var body = document.body,
    btn = document.getElementById( 'id' );
body.addEventListener( 'click', function( event ) {
    console.log( event.currentTarget === body );
    console.log( event.target === btn );
}, false );

when you click 'btn', and 'true' and 'true' will be appeared!

What is for Python what 'explode' is for PHP?

The alternative for explode in php is split.

The first parameter is the delimiter, the second parameter the maximum number splits. The parts are returned without the delimiter present (except possibly the last part). When the delimiter is None, all whitespace is matched. This is the default.

>>> "Rajasekar SP".split()
['Rajasekar', 'SP']

>>> "Rajasekar SP".split('a',2)
['R','j','sekar SP']

cannot connect to pc-name\SQLEXPRESS

go to services and start the ones related to SQL

How to "git clone" including submodules?

If it is a new project simply you can do like this :

$ git clone --recurse-submodules https://github.com/chaconinc/YourProjectName 

If it is already installed than :

$ cd YourProjectName (for the cases you are not at right directory) 
$ git submodule init
$ git submodule update

How to output (to a log) a multi-level array in a format that is human-readable?

Simple stuff:

Using print_r, var_dump or var_export should do it pretty nicely if you look at the result in view-source mode not in HTML mode or as @Joel Larson said if you wrap everything in a <pre> tag.

print_r is best for readability but it doesn't print null/false values.

var_dump is best for checking types of values and lengths and null/false values.

var_export is simmilar to var_dump but it can be used to get the dumped string.

The format returned by any of these is indented correctly in the source code and var_export can be used for logging since it can be used to return the dumped string.

Advanced stuff:

Use the xdebug plug-in for PHP this prints var_dumps as HTML formatted strings not as raw dump format and also allows you to supply a custom function you want to use for formatting.

How to add title to subplots in Matplotlib?

ax.title.set_text('My Plot Title') seems to work too.

fig = plt.figure()
ax1 = fig.add_subplot(221)
ax2 = fig.add_subplot(222)
ax3 = fig.add_subplot(223)
ax4 = fig.add_subplot(224)
ax1.title.set_text('First Plot')
ax2.title.set_text('Second Plot')
ax3.title.set_text('Third Plot')
ax4.title.set_text('Fourth Plot')
plt.show()

matplotlib add titles on subplots

Execution order of events when pressing PrimeFaces p:commandButton

I just love getting information like BalusC gives here - and he is kind enough to help SO many people with such GOOD information that I regard his words as gospel, but I was not able to use that order of events to solve this same kind of timing issue in my project. Since BalusC put a great general reference here that I even bookmarked, I thought I would donate my solution for some advanced timing issues in the same place since it does solve the original poster's timing issues as well. I hope this code helps someone:

        <p:pickList id="formPickList" 
                    value="#{mediaDetail.availableMedia}" 
                    converter="MediaPicklistConverter" 
                    widgetVar="formsPicklistWidget" 
                    var="mediaFiles" 
                    itemLabel="#{mediaFiles.mediaTitle}" 
                    itemValue="#{mediaFiles}" >
            <f:facet name="sourceCaption">Available Media</f:facet>
            <f:facet name="targetCaption">Chosen Media</f:facet>
        </p:pickList>

        <p:commandButton id="viewStream_btn" 
                         value="Stream chosen media" 
                         icon="fa fa-download"
                         ajax="true"
                         action="#{mediaDetail.prepareStreams}"                                              
                         update=":streamDialogPanel"
                         oncomplete="PF('streamingDialog').show()"
                         styleClass="ui-priority-primary"
                         style="margin-top:5px" >
            <p:ajax process="formPickList"  />
        </p:commandButton>

The dialog is at the top of the XHTML outside this form and it has a form of its own embedded in the dialog along with a datatable which holds additional commands for streaming the media that all needed to be primed and ready to go when the dialog is presented. You can use this same technique to do things like download customized documents that need to be prepared before they are streamed to the user's computer via fileDownload buttons in the dialog box as well.

As I said, this is a more complicated example, but it hits all the high points of your problem and mine. When the command button is clicked, the result is to first insure the backing bean is updated with the results of the pickList, then tell the backing bean to prepare streams for the user based on their selections in the pick list, then update the controls in the dynamic dialog with an update, then show the dialog box ready for the user to start streaming their content.

The trick to it was to use BalusC's order of events for the main commandButton and then to add the <p:ajax process="formPickList" /> bit to ensure it was executed first - because nothing happens correctly unless the pickList updated the backing bean first (something that was not happening for me before I added it). So, yea, that commandButton rocks because you can affect previous, pending and current components as well as the backing beans - but the timing to interrelate all of them is not easy to get a handle on sometimes.

Happy coding!

Convert InputStream to byte array in Java

In new version,

IOUtils.readAllBytes(inputStream)

jQuery .ajax() POST Request throws 405 (Method Not Allowed) on RESTful WCF

You must add this code in global.aspx:

 protected void Application_BeginRequest(object sender, EventArgs e)
        {
            HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "*");
            if (HttpContext.Current.Request.HttpMethod == "OPTIONS")
            {
                HttpContext.Current.Response.AddHeader("Cache-Control", "no-cache");
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Methods", "GET, POST");
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Headers", "Content-Type, Accept");
                HttpContext.Current.Response.AddHeader("Access-Control-Max-Age", "1728000");
                HttpContext.Current.Response.End();
            }
        }

How to restart counting from 1 after erasing table in MS Access?

In addition to all the concerns expressed about why you give a rat's ass what the ID value is (all are correct that you shouldn't), let me add this to the mix:

If you've deleted all the records from the table, compacting the database will reset the seed value back to its original value.

For a table where there are still records, and you've inserted a value into the Autonumber field that is lower than the highest value, you have to use @Remou's method to reset the seed value. This also applies if you want to reset to the Max+1 in a table where records have been deleted, e.g., 300 records, last ID of 300, delete 201-300, compact won't reset the counter (you have to use @Remou's method -- this was not the case in earlier versions of Jet, and, indeed, in early versions of Jet 4, the first Jet version that allowed manipulating the seed value programatically).

How to choose multiple files using File Upload Control?

You can try below code:

 Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
    Try
        Dim j As Integer = 0
        Dim hfc As HttpFileCollection = Request.Files
        Dim PathName As String
        For i As Integer = 0 To hfc.Count - 1
            Dim hpf As HttpPostedFile = hfc(i)

            If hpf.ContentLength > 0 Then
                hpf.SaveAs(Server.MapPath("~/E:\") & System.IO.Path.GetFileName(hpf.FileName))
                PathName = Server.MapPath(hpf.FileName)

                If j < hfc.Count Then
                    Dim strConnString As String = ConfigurationManager.ConnectionStrings("conString").ConnectionString
                    Dim sqlquery As String
                    sqlquery = "Insert_proc"
                    Dim con As New SqlConnection(strConnString)
                    Dim cmd As New SqlCommand(sqlquery, con)

                    cmd.CommandType = CommandType.StoredProcedure

                    cmd.Parameters.Add("@FilePath", SqlDbType.VarChar).Value = PathName
                    j = j + 1

                    Try
                        con.Open()
                        cmd.ExecuteNonQuery()


                    Catch ex As Exception
                        Throw ex
                    Finally
                        con.Close()
                        con.Dispose()

                    End Try
                    If j = hfc.Count Then
                        Exit Sub
                    End If
                End If
            End If
        Next

    Catch generatedExceptionName As Exception

        Throw
    End Try
End Sub

How to parse a string in JavaScript?

Use the Javascript string split() function.

var coolVar = '123-abc-itchy-knee';
var partsArray = coolVar.split('-');

// Will result in partsArray[0] == '123', partsArray[1] == 'abc', etc

Display the current time and date in an Android application

From How to get full date with correct format?:

Please, use

android.text.format.DateFormat.getDateFormat(Context context)
android.text.format.DateFormat.getTimeFormat(Context context)

to get valid time and date formats in sense of current user settings (12/24 time format, for example).

import android.text.format.DateFormat;

private void some() {
    final Calendar t = Calendar.getInstance();
    textView.setText(DateFormat.getTimeFormat(this/*Context*/).format(t.getTime()));
}

jQuery append and remove dynamic table row

You can dynamically add and delete table rows like this in the image using jQuery.. enter image description here

Here is html part...

<form id='students' method='post' name='students' action='index.php'>

    <table border="1" cellspacing="0">
      <tr>
        <th><input class='check_all' type='checkbox' onclick="select_all()"/></th>
        <th>S. No</th>
        <th>First Name</th>
        <th>Last Name</th>
        <th>Tamil</th>
        <th>English</th>
        <th>Computer</th>
        <th>Total</th>
      </tr>
      <tr>
        <td><input type='checkbox' class='case'/></td>
        <td>1.</td>
        <td><input type='text' id='first_name' name='first_name[]'/></td>
        <td><input type='text' id='last_name' name='last_name[]'/></td>
        <td><input type='text' id='tamil' name='tamil[]'/></td>
        <td><input type='text' id='english' name='english[]'/> </td>
        <td><input type='text' id='computer' name='computer[]'/></td>
        <td><input type='text' id='total' name='total[]'/> </td>
      </tr>
    </table>

    <button type="button" class='delete'>- Delete</button>
    <button type="button" class='addmore'>+ Add More</button>
    <p>
    <input type='submit' name='submit' value='submit' class='but'/></p>
</form>

Next need to include jquery...

<script src='jquery-1.9.1.min.js'></script>

Finally script which adds the table rows...

<script>
  var i=2;
  $(".addmore").on('click',function(){
    var data="<tr><td><input type='checkbox' class='case'/></td><td>"+i+".</td>";
        data +="<td><input type='text' id='first_name"+i+"' name='first_name[]'/></td> <td><input type='text' id='last_name"+i+"' name='last_name[]'/></td><td><input type='text' id='tamil"+i+"' name='tamil[]'/></td><td><input type='text' id='english"+i+"' name='english[]'/></td><td><input type='text' id='computer"+i+"' name='computer[]'/></td><td><input type='text' id='total"+i+"' name='total[]'/></td></tr>";
        $('table').append(data);
        i++;
});
</script>

Also refer demo & tutorial for this dynamically add & remove table rows

How to take character input in java

use :

char ch=**scanner.nextChar**()

Spring application context external properties?

<context:property-placeholder location="file:/apps/tomcat/ath/ath_conf/pcr.application.properties" />

This works for me. Local development machine path is C:\apps\tomcat\ath\ath_conf and in server /apps/tomcat/ath/ath_conf

Both works for me

CSS: transition opacity on mouse-out?

$(window).scroll(function() {    
    $('.logo_container, .slogan').css({
        "opacity" : ".1",
        "transition" : "opacity .8s ease-in-out"
    });
});

Check the fiddle: http://jsfiddle.net/2k3hfwo0/2/

How do I compile the asm generated by GCC?

Yes, gcc can also compile assembly source code. Alternatively, you can invoke as, which is the assembler. (gcc is just a "driver" program that uses heuristics to call C compiler, C++ compiler, assembler, linker, etc..)

Concatenate two NumPy arrays vertically

If the actual problem at hand is to concatenate two 1-D arrays vertically, and we are not fixated on using concatenate to perform this operation, I would suggest the use of np.column_stack:

In []: a = np.array([1,2,3])
In []: b = np.array([4,5,6])
In []: np.column_stack((a, b))
array([[1, 4],
       [2, 5],
       [3, 6]])

nginx 502 bad gateway

For me the error was in default file of Nginx located at /etc/nginx/sites-available/default

I noticed the version of php-fpm used was 7.0 and the php version i downloaded was 7.2 I simply changed the version to 7.2 and it worked.

fastcgi_pass unix:/var/run/php/php7.0-fpm.sock;

How to get Toolbar from fragment?

toolbar = (Toolbar) getView().findViewById(R.id.toolbar);
AppCompatActivity activity = (AppCompatActivity) getActivity();
activity.setSupportActionBar(toolbar);

Does C# have an equivalent to JavaScript's encodeURIComponent()?

You can use the Server object in the System.Web namespace

Server.UrlEncode, Server.UrlDecode, Server.HtmlEncode, and Server.HtmlDecode.

Edit: poster added that this was a windows application and not a web one as one would believe. The items listed above would be available from the HttpUtility class inside System.Web which must be added as a reference to the project.

error C2220: warning treated as error - no 'object' file generated

As a side-note, you can enable/disable individual warnings using #pragma. You can have a look at the documentation here

From the documentation:

// pragma_warning.cpp
// compile with: /W1
#pragma warning(disable:4700)
void Test() {
   int x;
   int y = x;   // no C4700 here
   #pragma warning(default:4700)   // C4700 enabled after Test ends
}

int main() {
   int x;
   int y = x;   // C4700
}

How to blur background images in Android

this might not be the most efficient solution but I had to use it since the wasabeef/Blurry library didn't work for me. this could be handy if you intend to have some getting-blurry animation:

1- you need to have 2 versions of the picture, normal one and the blurry one u make with photoshop or whatever

2- set the images fit on each other in your xml, then one of them could be seen and that's the upper one

3- set fadeout animation on the upper one:

final Animation fadeOut = new AlphaAnimation(1, 0);
        fadeOut.setInterpolator(new AccelerateInterpolator());
        fadeOut.setDuration(1000);


        fadeOut.setAnimationListener(new Animation.AnimationListener() {
            @Override
            public void onAnimationStart(Animation animation) {}

            @Override
            public void onAnimationEnd(Animation animation) {upperone.setVisibility(View.GONE);}

            @Override
            public void onAnimationRepeat(Animation animation) {}
        });

        upperone.startAnimation(fadeOut);

jQuery add blank option to top of list and make selected to existing dropdown

This worked:

$("#theSelectId").prepend("<option value='' selected='selected'></option>");

Firebug Output:

<select id="theSelectId">
  <option selected="selected" value=""/>
  <option value="volvo">Volvo</option>
  <option value="saab">Saab</option>
  <option value="mercedes">Mercedes</option>
  <option value="audi">Audi</option>
</select>

You could also use .prependTo if you wanted to reverse the order:

?$("<option>", { value: '', selected: true }).prependTo("#theSelectId");???????????

Using a remote repository with non-standard port

This avoids your problem rather than fixing it directly, but I'd recommend adding a ~/.ssh/config file and having something like this

Host git_host
HostName git.host.de
User root
Port 4019

then you can have

url = git_host:/var/cache/git/project.git

and you can also ssh git_host and scp git_host ... and everything will work out.

"Proxy server connection failed" in google chrome

  1. Open Google Chrome.
  2. Click Menu on the upper right side. Beside the STAR symbol (Bookmark).
  3. Click Show Advanced Settings.
  4. Scroll down and find Network.
  5. Click Change proxy settings.
  6. On the Connections tab, click LAN settings.
  7. Uncheck "Use a proxy server for your LAN."
  8. Then click OK.

Hope it helps .

How to use confirm using sweet alert?

swal({
    title: 'Are you sure?',
    text: "You won't be able to revert this!",
    type: 'warning',
    showCancelButton: true,
    confirmButtonColor: '#3085d6',
    cancelButtonColor: '#d33',
    confirmButtonText: 'Confirm!'
}).then(function(){
    alert("The confirm button was clicked");
}).catch(function(reason){
    alert("The alert was dismissed by the user: "+reason);
});

Get Character value from KeyCode in JavaScript... then trim

You can also use the read-only property key. It also respects special keys like shift etc. and is supported by IE9.

When a non-printable or special character is pressed, the value will be on of the defined key values like 'Shift' or 'Multiply'.

  • Keyboard     event.key
  • X             -> 'x'
  • Shift+X -> 'X'
  • F5            -> 'F5'

How to create a blank/empty column with SELECT query in oracle?

I guess you will get ORA-01741: illegal zero-length identifier if you use the following

SELECT "" AS Contact  FROM Customers;

And if you use the following 2 statements, you will be getting the same null value populated in the column.

SELECT '' AS Contact FROM Customers; OR SELECT null AS Contact FROM Customers;

How do you get the width and height of a multi-dimensional array?

You could also consider using getting the indexes of last elements in each specified dimensions using this as following;

int x = ary.GetUpperBound(0);
int y = ary.GetUpperBound(1);

Keep in mind that this gets the value of index as 0-based.

nodejs mongodb object id to string

The result returned by find is an array.

Try this instead:

console.log(user[0]["_id"]);

Reactjs convert html string to jsx

There are now safer methods to accomplish this. The docs have been updated with these methods.

Other Methods

  1. Easiest - Use Unicode, save the file as UTF-8 and set the charset to UTF-8.

    <div>{'First · Second'}</div>

  2. Safer - Use the Unicode number for the entity inside a Javascript string.

    <div>{'First \u00b7 Second'}</div>

    or

    <div>{'First ' + String.fromCharCode(183) + ' Second'}</div>

  3. Or a mixed array with strings and JSX elements.

    <div>{['First ', <span>&middot;</span>, ' Second']}</div>

  4. Last Resort - Insert raw HTML using dangerouslySetInnerHTML.

    <div dangerouslySetInnerHTML={{__html: 'First &middot; Second'}} />

How to set image width to be 100% and height to be auto in react native?

this may help for auto adjusting the image height having image 100% width

image: { width: "100%", resizeMode: "center" "contain", height: undefined, aspectRatio: 1, }

Postgres: How to convert a json string to text?

->> works for me.

postgres version:

<postgres.version>11.6</postgres.version>

Query:

select object_details->'valuationDate' as asofJson, object_details->>'valuationDate' as asofText from MyJsonbTable;

Output:

  asofJson       asofText
"2020-06-26"    2020-06-26
"2020-06-25"    2020-06-25
"2020-06-25"    2020-06-25
"2020-06-25"    2020-06-25

How to use subList()

You could use streams in Java 8. To always get 10 entries at the most, you could do:

dataList.stream().skip(5).limit(10).collect(Collectors.toList());
dataList.stream().skip(30).limit(10).collect(Collectors.toList());

Uncaught TypeError: undefined is not a function while using jQuery UI

Usually when you get this problem, it happens because a script is trying to reference an element that doesn't exist yet while the page is loading.

As richie mentioned: "The HTML parser will parse the HTML content from top to bottom..."

So you can add your JavaScript references to the bottom of the HTML file. This will not only improve performance; it will also ensure that all elements referenced in your script files have already been loaded by the HTML parser.

So you could have something like this:

<html>
    <head>
        <!--  Style sheet references and CSS definitions -->
    </head>
    <body>
        <!-- HTML markup and other page content -->

        <!-- JavaScript references. You could include jQuery here as well and do all your scripting here. -->
    </body>
</html>

How do I use Maven through a proxy?

Maven provides a built-in method of doing this, via a file called settings.xml, and this has been covered in other answers. However, it is customary, particularly in Linux, for command-line tools to automatically use the proxy specified by the environment variable https_proxy.

To follow the Don't repeat yourself principle (which is intended to help you avoid mistakes), it would be nice if mvn could automatically work with that too.

Here's a shell script that makes the necessary conversions:

#! /usr/bin/env bash

function javaproxy {
    ## using "Shell Parameter Expansion"
    request_scheme=$1 ; proxy=$2
    notscheme=$(echo ${proxy#*://}) ## parse
    scheme=$(echo ${proxy%${notscheme}}) ## remove
    scheme=$(echo ${scheme%://}) ## strip
    hostport=$(echo ${proxy#*//*}) ## parse
    host=$(echo ${hostport%:*}) ## parse
    port=$(echo ${hostport#${host}}) ## remove
    port=$(echo ${port#:}) ## strip
    scheme=$(echo ${scheme:-http}) ## default
    host=$(echo ${host:-localhost}) ## default
    port=$(echo ${port:-8080}) ## default
    echo -n " -D${request_scheme}.proxyHost=${host}"
    echo -n " -D${request_scheme}.proxyPort=${port}"
}

JTO=""

if [ $http_proxy ] ; then
    JTO="${JTO}$(javaproxy http ${http_proxy})"
fi

if [ $https_proxy ] ; then
    JTO="${JTO}$(javaproxy https ${https_proxy})"
fi

if [ $no_proxy ] ; then
    JTO="${JTO} -Dhttp.nonProxyHosts=$(echo \"${no_proxy}\"|tr ',' '|')"
fi

   export JAVA_TOOL_OPTIONS=${JTO}
   echo "JAVA_TOOL_OPTIONS=${JAVA_TOOL_OPTIONS}"

   mvn_friendliness_options+=--update-snapshots
   mvn ${mvn_friendliness_options} $@

You might name this something like proxied_mvn and run it as:

$ https_proxy=http://localhost:58080 ./proxied_mvn clean package

Alternatively, you could just move the environment setup into your startup scripts.

gotchas

There are many things that can go wrong when trying to configure Maven for access to a Nexus through a proxy. Hopefully, this script will help with some of the most finicky issues, but others remain:

  • Nexus credentials available and correct (only if required)

    Check with mvn help:effective-settings

  • Maven caching: "resolution will not be reattempted"

    mvn clean package --update-snapshots

  • Maven wall-of-text output -- you have to look closely at the output to make sure errors messages aren't subtly different between runs

  • Older versions of Java may require _JAVA_OPTIONS instead of JAVA_TOOL_OPTIONS.

epilogue

There is more than one kind of Proxy. Correspondingly, there is more than one way that this question has been interpreted -- contributing to the large number of disparate answers here.

I have explicitly addressed the case of a (forward HTTP/HTTPS) web proxy server, which is used to access the internet from within a company network (for some companies). This may be notably distinct from a SOCKS proxy, which has also been addressed in some answers here.

Oh by the way, since it uses JAVA_TOOL_OPTIONS, this solutions can be applied to running your other Java applications inside a proxy too.


Parting hint... My example above uses http://localhost:58080. This is because I've set up port-forwarding from my CLIENT_PROXY=localhost:58080 to the actual network proxy by using WSL on my remote-access client to run:

ssh $PROXY_CLIENT -R $CLIENT_PROXY:$SERVER_PROXY

LogCat message: The Google Play services resources were not found. Check your project configuration to ensure that the resources are included

I had this issue too. The way I solved it was the following:

  1. Delete the google-play-services_lib library-project.
  2. Remove the (now invalid) google-play-services_lib reference in [your project] > Properties > Android.
  3. Imported the google-play-services_lib library-project from android-sdk-x/extras/google_play_services/libproject. When you import a project, you get the option "Copy project into workspace". UNCHECK IT.
  4. Add the (now valid) google-play-services_lib reference to your project with [your project] > Properties > Android.

This did the trick for me. I hope it helps you too!

c++ integer->std::string conversion. Simple function?

Like mentioned earlier, I'd recommend boost lexical_cast. Not only does it have a fairly nice syntax:

#include <boost/lexical_cast.hpp>
std::string s = boost::lexical_cast<std::string>(i);

it also provides some safety:

try{
  std::string s = boost::lexical_cast<std::string>(i);
}catch(boost::bad_lexical_cast &){
 ...
}

Run a string as a command within a Bash script

your_command_string="..."
output=$(eval "$your_command_string")
echo "$output"

How to resize an image to fit in the browser window?

Use this code in your style tag

<style>
html {
  background: url(imagename) no-repeat center center fixed;
  background-size: cover;
  height: 100%;
  overflow: hidden;
}
</style>

Spring @ContextConfiguration how to put the right location for the xml

Simple solution is

@ContextConfiguration(locations = { "file:src/main/webapp/WEB-INF/applicationContext.xml" })

from spring forum

How to store a datetime in MySQL with timezone info

All the symptoms you describe suggest that you never tell MySQL what time zone to use so it defaults to system's zone. Think about it: if all it has is '2011-03-13 02:49:10', how can it guess that it's a local Tanzanian date?

As far as I know, MySQL doesn't provide any syntax to specify time zone information in dates. You have to change it a per-connection basis; something like:

SET time_zone = 'EAT';

If this doesn't work (to use named zones you need that the server has been configured to do so and it's often not the case) you can use UTC offsets because Tanzania does not observe daylight saving time at the time of writing but of course it isn't the best option:

SET time_zone = '+03:00';

matplotlib has no attribute 'pyplot'

pyplot is a sub-module of matplotlib which doesn't get imported with a simple import matplotlib.

>>> import matplotlib
>>> print matplotlib.pyplot
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'pyplot'
>>> import matplotlib.pyplot
>>> 

It seems customary to do: import matplotlib.pyplot as plt at which time you can use the various functions and classes it contains:

p = plt.plot(...)

Java IOException "Too many open files"

For UNIX:

As Stephen C has suggested, changing the maximum file descriptor value to a higher value avoids this problem.

Try looking at your present file descriptor capacity:

   $ ulimit -n

Then change the limit according to your requirements.

   $ ulimit -n <value>

Note that this just changes the limits in the current shell and any child / descendant process. To make the change "stick" you need to put it into the relevant shell script or initialization file.

Can I have a video with transparent background using HTML5 video tag?

webm format is the best solution for Chrome > 29, but it is not supported in Firefox IE and Safari, the best solution is using Flash (wmode="transparent"). but you have to forget "ios".

remote rejected master -> master (pre-receive hook declined)

If you run $ heroku logs you may get a "hint" to what the problem is. For me, Heroku could not detect what type of app I was creating. It required me to set the buildpack. Since I was creating a Node.js app, I just had to run $ heroku buildpacks:set https://github.com/heroku/heroku-buildpack-nodejs. You can read more about it here: https://devcenter.heroku.com/articles/buildpacks. No pushing issues after that.

I know this is an old question, but still posting this here incase someone else gets stuck.

How do I base64 encode (decode) in C?

I wrote one for use with C++, it's very fast, works with streams, free, and open source:

https://tmplusplus.svn.sourceforge.net/svnroot/tmplusplus/trunk/src/

Feel free to use it if it fits your purpose.

Edit: Added code inline by request.

The performance boost is acieved by using a lookup table for encoding and decoding. _UINT8 is an unsigned char on most OS's.

/** Static Base64 character encoding lookup table */
const char CBase64::encodeCharacterTable[65] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

/** Static Base64 character decoding lookup table */
const char CBase64::decodeCharacterTable[256] = {
    -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1
    ,-1,62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-1,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21
    ,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,-1,-1,-1,-1,-1,
    -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
    -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1
    ,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
    -1,-1,-1}; 

/*!
\brief Encodes binary data to base 64 character data
\param in The data to encode
\param out The encoded data as characters
*/
void CBase64::Encode(std::istream &in, std::ostringstream &out)
{
    char buff1[3];
    char buff2[4];
    _UINT8 i=0, j;
    while(in.readsome(&buff1[i++], 1))
        if (i==3)
        {
            out << encodeCharacterTable[(buff1[0] & 0xfc) >> 2];
            out << encodeCharacterTable[((buff1[0] & 0x03) << 4) + ((buff1[1] & 0xf0) >> 4)];
            out << encodeCharacterTable[((buff1[1] & 0x0f) << 2) + ((buff1[2] & 0xc0) >> 6)];
            out << encodeCharacterTable[buff1[2] & 0x3f];
            i=0;
        }

    if (--i)
    {
        for(j=i;j<3;j++) buff1[j] = '\0';

        buff2[0] = (buff1[0] & 0xfc) >> 2;
        buff2[1] = ((buff1[0] & 0x03) << 4) + ((buff1[1] & 0xf0) >> 4);
        buff2[2] = ((buff1[1] & 0x0f) << 2) + ((buff1[2] & 0xc0) >> 6);
        buff2[3] = buff1[2] & 0x3f;

        for (j=0;j<(i+1);j++) out << encodeCharacterTable[buff2[j]];

        while(i++<3) out << '=';
    }

}

/*!
\brief Decodes base 64 character data to binary data
\param in The character data to decode
\param out The decoded data
*/
void CBase64::Decode(std::istringstream &in, std::ostream &out)
{
    char buff1[4];
    char buff2[4];
    _UINT8 i=0, j;

    while(in.readsome(&buff2[i], 1) && buff2[i] != '=')
    {
        if (++i==4)
        {
            for (i=0;i!=4;i++)
                buff2[i] = decodeCharacterTable[buff2[i]];

            out << (char)((buff2[0] << 2) + ((buff2[1] & 0x30) >> 4));
            out << (char)(((buff2[1] & 0xf) << 4) + ((buff2[2] & 0x3c) >> 2));
            out << (char)(((buff2[2] & 0x3) << 6) + buff2[3]);

            i=0;
        }
    }

    if (i) 
    {
        for (j=i;j<4;j++) buff2[j] = '\0';
        for (j=0;j<4;j++) buff2[j] = decodeCharacterTable[buff2[j]];

        buff1[0] = (buff2[0] << 2) + ((buff2[1] & 0x30) >> 4);
        buff1[1] = ((buff2[1] & 0xf) << 4) + ((buff2[2] & 0x3c) >> 2);
        buff1[2] = ((buff2[2] & 0x3) << 6) + buff2[3];

        for (j=0;j<(i-1); j++) out << (char)buff1[j];
    }
}

Converting unix time into date-time via excel

TLDR

=(A1/86400)+25569

...and the format of the cell should be date.

If it doesn't work for you

  • If you get a number you forgot to format the output cell as a date.
  • If you get ##### you probably don't have a real Unix time. Check your timestamps in https://www.epochconverter.com/. Try to divide your input by 10, 100, 1000 or 10000**
  • You work with timestamps outside Excel's (very extended) limits.
  • You didn't replace A1 with the cell containing the timestamp ;-p

Explanation

Unix system represent a point in time as a number. Specifically the number of seconds* since a zero-time called the Unix epoch which is 1/1/1970 00:00 UTC/GMT. This number of seconds is called "Unix timestamp" or "Unix time" or "POSIX time" or just "timestamp" and sometimes (confusingly) "Unix epoch".

In the case of Excel they chose a different zero-time and step (because who wouldn't like variety in technical details?). So Excel counts days since 24 hours before 1/1/0000 UTC/GMT. So 25569 corresponds to 1/1/1970 00:00 UTC/GMT and 25570 to 2/1/1970 00:00.

Now please note that we have 86400 seconds per day (24 hours x60 minutes each x60 seconds) and you can understand what this formula does: A1/86400 converts seconds to days and +25569 adjusts for the offset between what is time-zero for Unix and what is time-zero for Excel.

By the way DATE(1970,1,1) will helpfully return 25569 for you in case you forget all this so a more "self-documenting" way to write our formula is:

=A1/(24*60*60) + DATE(1970,1,1)

P.S.: All these were already present in other answers and comments just not laid out as I like them and I don't feel it's OK to edit the hell out of another answer.


*: that's almost correct because you should not count leap seconds

**: E.g. in the case of this question the number was number of milliseconds since the the Unix epoch.

Bootstrap Responsive Text Size

Simplest way is to use dimensions in % or em. Just change the base font size everything will change.

Less

@media (max-width: @screen-xs) {
    body{font-size: 10px;}
}

@media (max-width: @screen-sm) {
    body{font-size: 14px;}
}


h5{
    font-size: 1.4rem;
}       

Look at all the ways at https://stackoverflow.com/a/21981859/406659

You could use viewport units (vh,vw...) but they dont work on Android < 4.4

Regex (grep) for multi-line search needed

I am not very good in grep. But your problem can be solved using AWK command. Just see

awk '/select/,/from/' *.sql

The above code will result from first occurence of select till first sequence of from. Now you need to verify whether returned statements are having customername or not. For this you can pipe the result. And can use awk or grep again.

ng-model for `<input type="file"/>` (with directive DEMO)

How to enable <input type="file"> to work with ng-model

Working Demo of Directive that Works with ng-model

The core ng-model directive does not work with <input type="file"> out of the box.

This custom directive enables ng-model and has the added benefit of enabling the ng-change, ng-required, and ng-form directives to work with <input type="file">.

_x000D_
_x000D_
angular.module("app",[]);

angular.module("app").directive("selectNgFiles", function() {
  return {
    require: "ngModel",
    link: function postLink(scope,elem,attrs,ngModel) {
      elem.on("change", function(e) {
        var files = elem[0].files;
        ngModel.$setViewValue(files);
      })
    }
  }
});
_x000D_
<script src="//unpkg.com/angular/angular.js"></script>
  <body ng-app="app">
    <h1>AngularJS Input `type=file` Demo</h1>
    
    <input type="file" select-ng-files ng-model="fileArray" multiple>

    <code><table ng-show="fileArray.length">
    <tr><td>Name</td><td>Date</td><td>Size</td><td>Type</td><tr>
    <tr ng-repeat="file in fileArray">
      <td>{{file.name}}</td>
      <td>{{file.lastModified | date  : 'MMMdd,yyyy'}}</td>
      <td>{{file.size}}</td>
      <td>{{file.type}}</td>
    </tr>
    </table></code>
    
  </body>
_x000D_
_x000D_
_x000D_

How can I see the request headers made by curl when sending a request to the server?

The only way I managed to see my outgoing headers (curl with php) was using the following options:

curl_setopt($ch, CURLOPT_HEADER, 1);
curl_setopt($ch, CURLINFO_HEADER_OUT, true);

Getting your debug info:

$data = curl_exec($ch);
var_dump($data);
var_dump(curl_getinfo($ch));

In C - check if a char exists in a char array

use strchr function when dealing with C strings.

const char * strchr ( const char * str, int character );

Here is an example of what you want to do.

/* strchr example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char invalids[] = ".@<>#";
  char * pch;
  pch=strchr(invalids,'s');//is s an invalid character?
  if (pch!=NULL)
  {
    printf ("Invalid character");
  }
  else 
  {
     printf("Valid character");
  } 
  return 0;
}

Use memchr when dealing with memory blocks (as not null terminated arrays)

const void * memchr ( const void * ptr, int value, size_t num );

/* memchr example */
#include <stdio.h>
#include <string.h>

int main ()
{
  char * pch;
  char invalids[] = "@<>#";
  pch = (char*) memchr (invalids, 'p', strlen(invalids));
  if (pch!=NULL)
    printf (p is an invalid character);
  else
    printf ("p valid character.\n");
  return 0;
}

http://www.cplusplus.com/reference/clibrary/cstring/memchr/

http://www.cplusplus.com/reference/clibrary/cstring/strchr/

"No such file or directory" but it exists

This error can mean that ./arm-mingw32ce-g++ doesn't exist (but it does), or that it exists and is a dynamically linked executable recognized by the kernel but whose dynamic loader is not available. You can see what dynamic loader is required by running ldd /arm-mingw32ce-g++; anything marked not found is the dynamic loader or a library that you need to install.

If you're trying to run a 32-bit binary on an amd64 installation:

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

Please reformulate your question. Your first sentence does not make sense. .

To address your question:

http://ip.of.server/ should work in principle. However, depending on configuration (virtual hosting) only using the correct host name may work.

At any rate, if you have a network, you should properly configure DNS, otherwise all kinds of problems (such as this) may occur.

How to update one file in a zip archive

Use the update flag: -u

Example:

zip -ur existing.zip myFolder

This command will compress and add myFolder (and it's contents) to the existing.zip.


Advanced Usage:

The update flag actually compares the incoming files against the existing ones and will either add new files, or update existing ones.

Therefore, if you want to add/update a specific subdirectory within the zip file, just update the source as desired, and then re-zip the entire source with the -u flag. Only the changed files will be zipped.

If you don't have access to the source files, you can unzip the zip file, then update the desired files, and then re-zip with the -u flag. Again, only the changed files will be zipped.

Example:

Original Source Structure


ParentDir
+-- file1.txt
+-- file2.txt
+-- ChildDir
¦   +-- file3.txt
¦   +-- Logs
¦   ¦   +-- logs1.txt
¦   ¦   +-- logs2.txt
¦   ¦   +-- logs3.txt

Updated Source Structure


ParentDir
+-- file1.txt
+-- file2.txt
+-- ChildDir
¦   +-- file3.txt
¦   +-- Logs
¦   ¦   +-- logs1.txt
¦   ¦   +-- logs2.txt
¦   ¦   +-- logs3.txt 
¦   ¦   +-- logs4.txt <-- NEW FILE 

Usage

$ zip -ur existing.zip ParentDir 
> updating: ParentDir/ChildDir/Logs (stored 0%)
>   adding: ParentDir/ChildDir/Logs/logs4.txt (stored 96%)

Insert Multiple Rows Into Temp Table With SQL Server 2012

When using SQLFiddle, make sure that the separator is set to GO. Also the schema build script is executed in a different connection from the run script, so a temp table created in the one is not visible in the other. This fiddle shows that your code is valid and working in SQL 2012:

SQL Fiddle

MS SQL Server 2012 Schema Setup:

Query 1:

CREATE TABLE #Names
  ( 
    Name1 VARCHAR(100),
    Name2 VARCHAR(100)
  ) 

INSERT INTO #Names
  (Name1, Name2)
VALUES
  ('Matt', 'Matthew'),
  ('Matt', 'Marshal'),
  ('Matt', 'Mattison')

SELECT * FROM #NAMES

Results:

| NAME1 |    NAME2 |
--------------------
|  Matt |  Matthew |
|  Matt |  Marshal |
|  Matt | Mattison |

Here a SSMS 2012 screenshot: enter image description here

Collapsing Sidebar with Bootstrap

Via Angular: using ng-class of Angular, we can hide and show the side bar.

http://jsfiddle.net/DVE4f/359/

<div class="container" style="width:100%" ng-app ng-controller="AppCtrl">
<div class="row">
    <div ng-class="showgraphSidebar ? 'col-xs-3' : 'hidden'" id="colPush" >
        Sidebar
    </div>
    <div ng-class="showgraphSidebar ? 'col-xs-9' : 'col-xs-12'"  id="colMain"  >
        <button  ng-click='toggle()' >Sidebar Toggle</a>
    </div>    
  </div>
</div>

.

function AppCtrl($scope) {
    $scope.showgraphSidebar = false;
    $scope.toggle = function() {
        $scope.showgraphSidebar = !$scope.showgraphSidebar;
    }
}

Bash script - variable content as a command to run

line=$((${RANDOM} % $(wc -l < /etc/passwd)))
sed -n "${line}p" /etc/passwd

just with your file instead.

In this example I used the file /etc/password, using the special variable ${RANDOM} (about which I learned here), and the sed expression you had, only difference is that I am using double quotes instead of single to allow the variable expansion.

Content Type text/xml; charset=utf-8 was not supported by service

I had this error and all the configurations mentioned above were correct however I was still getting "The client and service bindings may be mismatched" error.

What resolved my error, was matching the messageEncoding attribute values in the following node of service and client config files. They were different in mine, service was Text and client Mtom. Changing service to Mtom to match client's, resolved the issue.

<configuration>
  <system.serviceModel>
      <bindings>
           <basicHttpBinding>
              <binding name="BasicHttpBinding_IMySevice" ... messageEncoding="Mtom">
              ...
              </binding>
           </basicHttpBinding>
      </bindings>
  </system.serviceModel>
</configuration>

SmtpException: Unable to read data from the transport connection: net_io_connectionclosed

Does your SMTP library supports encrypted connection ? The mail server might be expecting secure TLS connection and hence closing the connection in absence of a TLS handshake

APR based Apache Tomcat Native library was not found on the java.library.path?

My case: Seeing the same INFO message.

Centos 6.2 x86_64 Tomcat 6.0.24

This fixed the problem for me:

yum install tomcat-native

boom!

document.getElementById replacement in angular4 / typescript?

You can just inject the DOCUMENT token into the constructor and use the same functions on it

import { Inject }  from '@angular/core';
import { DOCUMENT } from '@angular/common'; 

@Component({...})
export class AppCmp {
   constructor(@Inject(DOCUMENT) document) {
      document.getElementById('el');
   }
}

Or if the element you want to get is in that component, you can use template references.

How can one develop iPhone apps in Java?

I'm answering this question 2 years down the line and I must stress that I did have pretty much the same problem as you did. However I'm so happy that Android has evolved into what it is today.

Having said that, I do regret that I did not learn C/C++ while I could have and I don't want to blame my teachers for it cos where was my brain when the time was right?

I'm sunk in Java today and I'm glad that I did not make the mistake of learning too many languages and being less productive... However I did learn HTML5 which really made things a lot easier, maybe someday, I might get motivated to learn C/C++ . Or if I get an Apple mac at a real throw-away price, I might learn Objective-C :)

Filter output in logcat by tagname

Here is how I create a tag:

private static final String TAG = SomeActivity.class.getSimpleName();
 Log.d(TAG, "some description");

You could use getCannonicalName

Here I have following TAG filters:

  • any (*) View - VERBOSE
  • any (*) Activity - VERBOSE
  • any tag starting with Xyz(*) - ERROR
  • System.out - SILENT (since I am using Log in my own code)

Here what I type in terminal:

$  adb logcat *View:V *Activity:V Xyz*:E System.out:S

How to generate a random String in Java

I think the following class code will help you. It supports multithreading but you can do some improvement like remove sync block and and sync to getRandomId() method.

public class RandomNumberGenerator {

private static final Set<String> generatedNumbers = new HashSet<String>();

public RandomNumberGenerator() {
}

public static void main(String[] args) {
    final int maxLength = 7;
    final int maxTry = 10;

    for (int i = 0; i < 10; i++) {
        System.out.println(i + ". studentId=" + RandomNumberGenerator.getRandomId(maxLength, maxTry));
    }
}

public static String getRandomId(final int maxLength, final int maxTry) {
    final Random random = new Random(System.nanoTime());
    final int max = (int) Math.pow(10, maxLength);
    final int maxMin = (int) Math.pow(10, maxLength-1);
    int i = 0;
    boolean unique = false;
    int randomId = -1;
    while (i < maxTry) {
        randomId = random.nextInt(max - maxMin - 1) + maxMin;

        synchronized (generatedNumbers) {
            if (generatedNumbers.contains(randomId) == false) {
                unique = true;
                break;
            }
        }
        i++;
    }
    if (unique == false) {
        throw new RuntimeException("Cannot generate unique id!");
    }

    synchronized (generatedNumbers) {
        generatedNumbers.add(String.valueOf(randomId));
    }

    return String.valueOf(randomId);
}

}

How to compile C programming in Windows 7?

Compiling Programs on Windows 7:

You have to download configured Borland Compiler from http://www.4shared.com/get/Gs41_5yA/borland_for_graphics.html or http://dwij.co.in/graphics-c-programming-for-windows-7-borland-compiler/.

Put your Borland’s ‘bin’ folder into Environmental Variables.
Now go inside folder ‘bin’ & edit file bcc32.cfg as per your folder structure. This file contains settings of headers & libraries.

-I"D:\Borland\include;"
-L"D:\Borland\lib;D:\Borland\Lib\PSDK"

Now create any C/C++ Program say myprogram.cpp
Use following command to compile this bunch of code:

F:\>bcc32 myprogram.cpp

How to center-justify the last line of text in CSS?

You can also split the element into two via HTML + JS.

HTML:

<div class='justificator'>
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, 
when an unknown printer took a galley of type and scrambled it to make a 
type specimen book.
</div>

JS:

function justify() {
    // Query for elements search
    let arr = document.querySelectorAll('.justificator');
    for (let current of arr) {
        let oldHeight = current.offsetHeight;
        // Stores cut part
        let buffer = '';

        if (current.innerText.lastIndexOf(' ') >= 0) {
            while (current.offsetHeight == oldHeight) {
                let lastIndex = current.innerText.lastIndexOf(' ');
                buffer = current.innerText.substring(lastIndex) + buffer;
                current.innerText = current.innerText.substring(0, lastIndex);
            }
            let sibling = current.cloneNode(true);
            sibling.innerText = buffer;
            sibling.classList.remove('justificator');
            // Center
            sibling.style['text-align'] = 'center';


            current.style['text-align'] = 'justify';
            // For devices that do support text-align-last
            current.style['text-align-last'] = 'justify';
            // Insert new element after current
            current.parentNode.insertBefore(sibling, current.nextSibling);
        }
    }
}
document.addEventListener("DOMContentLoaded", justify);

Here is an example with div and p tags

_x000D_
_x000D_
function justify() {_x000D_
    // Query for elements search_x000D_
    let arr = document.querySelectorAll('.justificator');_x000D_
    for (let current of arr) {_x000D_
        let oldHeight = current.offsetHeight;_x000D_
        // Stores cut part_x000D_
        let buffer = '';_x000D_
_x000D_
        if (current.innerText.lastIndexOf(' ') >= 0) {_x000D_
            while (current.offsetHeight == oldHeight) {_x000D_
                let lastIndex = current.innerText.lastIndexOf(' ');_x000D_
                buffer = current.innerText.substring(lastIndex) + buffer;_x000D_
                current.innerText = current.innerText.substring(0, lastIndex);_x000D_
            }_x000D_
            let sibling = current.cloneNode(true);_x000D_
            sibling.innerText = buffer;_x000D_
            sibling.classList.remove('justificator');_x000D_
            // Center_x000D_
            sibling.style['text-align'] = 'center';_x000D_
            // For devices that do support text-align-last_x000D_
            current.style['text-align-last'] = 'justify';_x000D_
            current.style['text-align'] = 'justify';_x000D_
            // Insert new element after current_x000D_
            current.parentNode.insertBefore(sibling, current.nextSibling);_x000D_
        }_x000D_
    }_x000D_
}_x000D_
justify();
_x000D_
p.justificator {_x000D_
    margin-bottom: 0px;_x000D_
}_x000D_
p.justificator + p {_x000D_
    margin-top: 0px;_x000D_
}
_x000D_
<div class='justificator'>_x000D_
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, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum._x000D_
</div>_x000D_
<p class='justificator'>It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum._x000D_
</p><p>Some other text</p>
_x000D_
_x000D_
_x000D_ Disadvantage: doesn't work when page width changes dynamically.

How to validate domain credentials?

I`m using the following code to validate credentials. The method shown below will confirm if the credentials are correct and if not wether the password is expired or needs change.

I`ve been looking for something like this for ages... So i hope this helps someone!

using System;
using System.DirectoryServices;
using System.DirectoryServices.AccountManagement;
using System.Runtime.InteropServices;

namespace User
{
    public static class UserValidation
    {
        [DllImport("advapi32.dll", SetLastError = true)]
        static extern bool LogonUser(string principal, string authority, string password, LogonTypes logonType, LogonProviders logonProvider, out IntPtr token);
        [DllImport("kernel32.dll", SetLastError = true)]
        static extern bool CloseHandle(IntPtr handle);
        enum LogonProviders : uint
        {
            Default = 0, // default for platform (use this!)
            WinNT35,     // sends smoke signals to authority
            WinNT40,     // uses NTLM
            WinNT50      // negotiates Kerb or NTLM
        }
        enum LogonTypes : uint
        {
            Interactive = 2,
            Network = 3,
            Batch = 4,
            Service = 5,
            Unlock = 7,
            NetworkCleartext = 8,
            NewCredentials = 9
        }
        public  const int ERROR_PASSWORD_MUST_CHANGE = 1907;
        public  const int ERROR_LOGON_FAILURE = 1326;
        public  const int ERROR_ACCOUNT_RESTRICTION = 1327;
        public  const int ERROR_ACCOUNT_DISABLED = 1331;
        public  const int ERROR_INVALID_LOGON_HOURS = 1328;
        public  const int ERROR_NO_LOGON_SERVERS = 1311;
        public  const int ERROR_INVALID_WORKSTATION = 1329;
        public  const int ERROR_ACCOUNT_LOCKED_OUT = 1909;      //It gives this error if the account is locked, REGARDLESS OF WHETHER VALID CREDENTIALS WERE PROVIDED!!!
        public  const int ERROR_ACCOUNT_EXPIRED = 1793;
        public  const int ERROR_PASSWORD_EXPIRED = 1330;

        public static int CheckUserLogon(string username, string password, string domain_fqdn)
        {
            int errorCode = 0;
            using (PrincipalContext pc = new PrincipalContext(ContextType.Domain, domain_fqdn, "ADMIN_USER", "PASSWORD"))
            {
                if (!pc.ValidateCredentials(username, password))
                {
                    IntPtr token = new IntPtr();
                    try
                    {
                        if (!LogonUser(username, domain_fqdn, password, LogonTypes.Network, LogonProviders.Default, out token))
                        {
                            errorCode = Marshal.GetLastWin32Error();
                        }
                    }
                    catch (Exception)
                    {
                        throw;
                    }
                    finally
                    {
                        CloseHandle(token);
                    }
                }
            }
            return errorCode;
        }
    }

How to create a density plot in matplotlib?

Five years later, when I Google "how to create a kernel density plot using python", this thread still shows up at the top!

Today, a much easier way to do this is to use seaborn, a package that provides many convenient plotting functions and good style management.

import numpy as np
import seaborn as sns
data = [1.5]*7 + [2.5]*2 + [3.5]*8 + [4.5]*3 + [5.5]*1 + [6.5]*8
sns.set_style('whitegrid')
sns.kdeplot(np.array(data), bw=0.5)

enter image description here

Creating a REST API using PHP

In your example, it’s fine as it is: it’s simple and works. The only things I’d suggest are:

  1. validating the data POSTed
  2. make sure your API is sending the Content-Type header to tell the client to expect a JSON response:

    header('Content-Type: application/json');
    echo json_encode($response);
    

Other than that, an API is something that takes an input and provides an output. It’s possible to “over-engineer” things, in that you make things more complicated that need be.

If you wanted to go down the route of controllers and models, then read up on the MVC pattern and work out how your domain objects fit into it. Looking at the above example, I can see maybe a MathController with an add() action/method.

There are a few starting point projects for RESTful APIs on GitHub that are worth a look.

Getting Excel to refresh data on sheet from within VBA

You might also try

Application.CalculateFull

or

Application.CalculateFullRebuild

if you don't mind rebuilding all open workbooks, rather than just the active worksheet. (CalculateFullRebuild rebuilds dependencies as well.)

There is no tracking information for the current branch

See: git checkout tag, git pull fails in branch

If like me you need to do this all the time, you can set up an alias to do it automatically by adding the following to your .gitconfig file:

[alias]
    set-upstream = \
       !git branch \
           --set-upstream-to=origin/`git symbolic-ref --short HEAD`

When you see the message There is no tracking information..., run:

 git set-upstream
 git push

Thanks to https://zarino.co.uk/post/git-set-upstream/

How do I invoke a Java method when given the method name as a string?

To complete my colleague's answers, You might want to pay close attention to:

  • static or instance calls (in one case, you do not need an instance of the class, in the other, you might need to rely on an existing default constructor that may or may not be there)
  • public or non-public method call (for the latter,you need to call setAccessible on the method within an doPrivileged block, other findbugs won't be happy)
  • encapsulating into one more manageable applicative exception if you want to throw back the numerous java system exceptions (hence the CCException in the code below)

Here is an old java1.4 code which takes into account those points:

/**
 * Allow for instance call, avoiding certain class circular dependencies. <br />
 * Calls even private method if java Security allows it.
 * @param aninstance instance on which method is invoked (if null, static call)
 * @param classname name of the class containing the method 
 * (can be null - ignored, actually - if instance if provided, must be provided if static call)
 * @param amethodname name of the method to invoke
 * @param parameterTypes array of Classes
 * @param parameters array of Object
 * @return resulting Object
 * @throws CCException if any problem
 */
public static Object reflectionCall(final Object aninstance, final String classname, final String amethodname, final Class[] parameterTypes, final Object[] parameters) throws CCException
{
    Object res;// = null;
    try {
        Class aclass;// = null;
        if(aninstance == null)
        {
            aclass = Class.forName(classname);
        }
        else
        {
            aclass = aninstance.getClass();
        }
        //Class[] parameterTypes = new Class[]{String[].class};
    final Method amethod = aclass.getDeclaredMethod(amethodname, parameterTypes);
        AccessController.doPrivileged(new PrivilegedAction() {
    public Object run() {
                amethod.setAccessible(true);
                return null; // nothing to return
            }
        });
        res = amethod.invoke(aninstance, parameters);
    } catch (final ClassNotFoundException e) {
        throw new CCException.Error(PROBLEM_TO_ACCESS+classname+CLASS, e);
    } catch (final SecurityException e) {
        throw new CCException.Error(PROBLEM_TO_ACCESS+classname+GenericConstants.HASH_DIESE+ amethodname + METHOD_SECURITY_ISSUE, e);
    } catch (final NoSuchMethodException e) {
        throw new CCException.Error(PROBLEM_TO_ACCESS+classname+GenericConstants.HASH_DIESE+ amethodname + METHOD_NOT_FOUND, e);
    } catch (final IllegalArgumentException e) {
        throw new CCException.Error(PROBLEM_TO_ACCESS+classname+GenericConstants.HASH_DIESE+ amethodname + METHOD_ILLEGAL_ARGUMENTS+String.valueOf(parameters)+GenericConstants.CLOSING_ROUND_BRACKET, e);
    } catch (final IllegalAccessException e) {
        throw new CCException.Error(PROBLEM_TO_ACCESS+classname+GenericConstants.HASH_DIESE+ amethodname + METHOD_ACCESS_RESTRICTION, e);
    } catch (final InvocationTargetException e) {
    throw new CCException.Error(PROBLEM_TO_ACCESS+classname+GenericConstants.HASH_DIESE+ amethodname + METHOD_INVOCATION_ISSUE, e);
    } 
    return res;
}

How to style a clicked button in CSS

This button will appear yellow initially. On hover it will turn orange. When you click it, it will turn red. I used :hover and :focus to adapt the style. (The :active selector is usually used of links (i.e. <a> tags))

_x000D_
_x000D_
button{_x000D_
  background-color:yellow;_x000D_
}_x000D_
_x000D_
button:hover{background-color:orange;}_x000D_
_x000D_
button:focus{background-color:red;}_x000D_
_x000D_
a {_x000D_
  color: orange;_x000D_
}_x000D_
_x000D_
a.button{_x000D_
  color:green;_x000D_
  text-decoration: none;_x000D_
}_x000D_
_x000D_
a:visited {_x000D_
  color: purple;_x000D_
}_x000D_
_x000D_
a:active {_x000D_
  color: blue;_x000D_
}
_x000D_
<button>_x000D_
Hover and Click!_x000D_
</button>_x000D_
<br><br>_x000D_
_x000D_
<a href="#">Hello</a><br><br>_x000D_
<a class="button" href="#">Bye</a>
_x000D_
_x000D_
_x000D_

I can't install pyaudio on Windows? How to solve "error: Microsoft Visual C++ 14.0 is required."?

First run your IDE or CMD as Administrator and run the following:

pip install pipwin
pipwin install pyaudio

List all of the possible goals in Maven 2?

Strange nobody listed an actual command to do it:

mvn help:describe -e -Dplugin=site

If you want to list all goals of the site plugin. Output:

Name: Apache Maven Site Plugin Description: The Maven Site Plugin is a plugin that generates a site for the current project. Group Id: org.apache.maven.plugins Artifact Id: maven-site-plugin Version: 3.7.1 Goal Prefix: site

This plugin has 9 goals:

site:attach-descriptor Description: Adds the site descriptor (site.xml) to the list of files to be installed/deployed. For Maven-2.x this is enabled by default only when the project has pom packaging since it will be used by modules inheriting, but this can be enabled for other projects packaging if needed. This default execution has been removed from the built-in lifecycle of Maven 3.x for pom-projects. Users that actually use those projects to provide a common site descriptor for sub modules will need to explicitly define this goal execution to restore the intended behavior.

site:deploy Description: Deploys the generated site using wagon supported protocols to the site URL specified in the section of the POM. For scp protocol, the website files are packaged by wagon into zip archive, then the archive is transfered to the remote host, next it is un-archived which is much faster than making a file by file copy.

site:effective-site Description: Displays the effective site descriptor as an XML for this build, after inheritance and interpolation of site.xml, for the first locale.

site:help Description: Display help information on maven-site-plugin. Call mvn site:help -Ddetail=true -Dgoal= to display parameter details.

site:jar Description: Bundles the site output into a JAR so that it can be deployed to a repository.

site:run Description: Starts the site up, rendering documents as requested for faster editing. It uses Jetty as the web server.

site:site Description: Generates the site for a single project. Note that links between module sites in a multi module build will not work, since local build directory structure doesn't match deployed site.

site:stage Description: Deploys the generated site to a local staging or mock directory based on the site URL specified in the section of the POM. It can be used to test that links between module sites in a multi-module build work.

This goal requires the site to already have been generated using the site goal, such as by calling mvn site.

site:stage-deploy Description: Deploys the generated site to a staging or mock URL to the site URL specified in the section of the POM, using wagon supported protocols

For more information, run 'mvn help:describe [...] -Ddetail'

More details on https://mkyong.com/maven/how-to-display-maven-plugin-goals-and-parameters/