The model backing the 'ApplicationDbContext' context has changed since the database was created

remove all tables identity

Delete _MigrationHistory
Delete AspNetRoles
Delete AspNetUserClaims
Delete AspNetUserLogins
Delete AspNetRoles
Delete AspNetUser

Entity Framework Provider type could not be loaded?

remove the entity framework from the project via nuget then add it back in.

Unable to update the EntitySet - because it has a DefiningQuery and no <UpdateFunction> element exist

I had the same issue. As this thread said, My table didn't have a PK, so I set the PK and ran the code. But unfortunately error came again. What I did next was, deleted the DB connection (delete .edmx file in Model folder of Solution Explorer) and recreated it. Error gone after that. Thanks everyone for sharing your experiences. It save lots of time.

Unable to find the requested .Net Framework Data Provider. It may not be installed. - when following mvc3 asp.net tutorial

I had the same when following MvcMusicStore Tutorial in Part 4 and replaced the given connection String with this:

add name="MusicStoreEntities" connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;database=MvcMusicStore;User ID=sa;password=" providerName="System.Data.SqlClient"/>

It worked for me.

Why am I getting this error: No mapping specified for the following EntitySet/AssociationSet - Entity1?

I had set everything correctly (cardinalities and dependent properties) but could not figure out why I keep receiving error. Finally figured out that, EF generated a column in dependent table on its own (table_tablecolumn) and it does not have any relation to the table, so no mapping was specified. I had to delete the column in EDMX file and rebuild the solution which fixed the issue. I am using DB approach.

The conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value

you have to match the input format of your date field to the required entity format which is yyyy/mm/dd

jQuery and AJAX response header

If this is a CORS request, you may see all headers in debug tools (such as Chrome->Inspect Element->Network), but the xHR object will only retrieve the header (via xhr.getResponseHeader('Header')) if such a header is a simple response header:

Content-Type
Last-modified
Content-Language
Cache-Control
Expires
Pragma

If it is not in this set, it must be present in the Access-Control-Expose-Headers header returned by the server.

About the case in question, if it is a CORS request, one will only be able to retrieve the Location header through the XMLHttpRequest object if, and only if, the header below is also present:

Access-Control-Expose-Headers: Location

If its not a CORS request, XMLHttpRequest will have no problem retrieving it.

SQL GROUP BY CASE statement with aggregate function

While Shannon's answer is technically correct, it looks like overkill.

The simple solution is that you need to put your summation outside of the case statement. This should do the trick:

sum(CASE WHEN col1 > col2 THEN col3*col4 ELSE 0 END) AS some_product

Basically, your old code tells SQL to execute the sum(X*Y) for each line individually (leaving each line with its own answer that can't be grouped).

The code line I have written takes the sum product, which is what you want.

Bootstrap $('#myModal').modal('show') is not working

Please also make sure that the modal div is nested inside your <body> element.

Create a tar.xz in one command

Use the -J compression option for xz. And remember to man tar :)

tar cfJ <archive.tar.xz> <files>

Edit 2015-08-10:

If you're passing the arguments to tar with dashes (ex: tar -cf as opposed to tar cf), then the -f option must come last, since it specifies the filename (thanks to @A-B-B for pointing that out!). In that case, the command looks like:

tar -cJf <archive.tar.xz> <files>

Java regular expression OR operator

You can just use the pipe on its own:

"string1|string2"

for example:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|string2", "blah"));

Output:

blah, blah, string3

The main reason to use parentheses is to limit the scope of the alternatives:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string(1|2)", "blah"));

has the same output. but if you just do this:

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|2", "blah"));

you get:

blah, stringblah, string3

because you've said "string1" or "2".

If you don't want to capture that part of the expression use ?::

String s = "string1, string2, string3";
System.out.println(s.replaceAll("string(?:1|2)", "blah"));

Cannot find vcvarsall.bat when running a Python script

In 2015, if you still getting this confusing error, blame python default setuptools that PIP uses.

Download and install minimal Microsoft Visual C++ Compiler for Python 2.7 required to compile python 2.7 modules from http://www.microsoft.com/en-in/download/details.aspx?id=44266
Update your setuptools - pip install -U setuptools
Install whatever python package you want that require C compilation. pip install blahblah

It will work fine.

UPDATE: It won't work fine for all libraries. I still get some error with few modules, that require lib-headers. They only thing that work flawlessly is Linux platform

Launch custom android application from android browser

You need to add a pseudo-hostname to the CALLBACK_URL 'app://' doesn't make sense as a URL and cannot be parsed.

Return positions of a regex match() in Javascript?

var str = "The rain in SPAIN stays mainly in the plain";

function searchIndex(str, searchValue, isCaseSensitive) {
  var modifiers = isCaseSensitive ? 'gi' : 'g';
  var regExpValue = new RegExp(searchValue, modifiers);
  var matches = [];
  var startIndex = 0;
  var arr = str.match(regExpValue);

  [].forEach.call(arr, function(element) {
    startIndex = str.indexOf(element, startIndex);
    matches.push(startIndex++);
  });

  return matches;
}

console.log(searchIndex(str, 'ain', true));

Http Post request with content type application/x-www-form-urlencoded not working in Spring

Remove @ResponseBody annotation from your use parameters in method. Like this;

   @Autowired
    ProjectService projectService;

    @RequestMapping(path = "/add", method = RequestMethod.POST)
    public ResponseEntity<Project> createNewProject(Project newProject){
        Project project = projectService.save(newProject);

        return new ResponseEntity<Project>(project,HttpStatus.CREATED);
    }

How to add images to README.md on GitHub?

I usually host the image on the site, this can link to any hosted image. Just toss this in the readme. Works for .rst files, not sure about .md

.. image:: https://url/path/to/image
   :height: 100px
   :width: 200 px
   :scale: 50 %

How to use MapView in android using google map V2?

I created dummy sample for Google Maps v2 Android with Kotlin and AndroidX

You can find complete project here: github-link

`MainActivity.kt`

class MainActivity : AppCompatActivity() {

val position = LatLng(-33.920455, 18.466941)

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    with(mapView) {
        // Initialise the MapView
        onCreate(null)
        // Set the map ready callback to receive the GoogleMap object
        getMapAsync{
            MapsInitializer.initialize(applicationContext)
            setMapLocation(it)
        }
    }
}

private fun setMapLocation(map : GoogleMap) {
    with(map) {
        moveCamera(CameraUpdateFactory.newLatLngZoom(position, 13f))
        addMarker(MarkerOptions().position(position))
        mapType = GoogleMap.MAP_TYPE_NORMAL
        setOnMapClickListener {
            Toast.makeText(this@MainActivity, "Clicked on map", Toast.LENGTH_SHORT).show()
        }
    }
}

override fun onResume() {
    super.onResume()
    mapView.onResume()
}

override fun onPause() {
    super.onPause()
    mapView.onPause()
}

override fun onDestroy() {
    super.onDestroy()
    mapView.onDestroy()
}

override fun onLowMemory() {
    super.onLowMemory()
    mapView.onLowMemory()
 }
}

`AndroidManifest.xml`

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools" package="com.murgupluoglu.googlemap">

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

<application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme"
        tools:ignore="GoogleAppIndexingWarning">
    <meta-data
            android:name="com.google.android.geo.API_KEY"
            android:value="API_KEY_HERE" />
    <activity android:name=".MainActivity">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>

            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
</application>

</manifest>

`activity_main.xml`

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

<com.google.android.gms.maps.MapView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:id="@+id/mapView"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"/>

</androidx.constraintlayout.widget.ConstraintLayout>

How to upload, display and save images using node.js and express

First of all, you should make an HTML form containing a file input element. You also need to set the form's enctype attribute to multipart/form-data:

<form method="post" enctype="multipart/form-data" action="/upload">
    <input type="file" name="file">
    <input type="submit" value="Submit">
</form>

Assuming the form is defined in index.html stored in a directory named public relative to where your script is located, you can serve it this way:

const http = require("http");
const path = require("path");
const fs = require("fs");

const express = require("express");

const app = express();
const httpServer = http.createServer(app);

const PORT = process.env.PORT || 3000;

httpServer.listen(PORT, () => {
  console.log(`Server is listening on port ${PORT}`);
});

// put the HTML file containing your form in a directory named "public" (relative to where this script is located)
app.get("/", express.static(path.join(__dirname, "./public")));

Once that's done, users will be able to upload files to your server via that form. But to reassemble the uploaded file in your application, you'll need to parse the request body (as multipart form data).

In Express 3.x you could use express.bodyParser middleware to handle multipart forms but as of Express 4.x, there's no body parser bundled with the framework. Luckily, you can choose from one of the many available multipart/form-data parsers out there. Here, I'll be using multer:

You need to define a route to handle form posts:

const multer = require("multer");

const handleError = (err, res) => {
  res
    .status(500)
    .contentType("text/plain")
    .end("Oops! Something went wrong!");
};

const upload = multer({
  dest: "/path/to/temporary/directory/to/store/uploaded/files"
  // you might also want to set some limits: https://github.com/expressjs/multer#limits
});


app.post(
  "/upload",
  upload.single("file" /* name attribute of <file> element in your form */),
  (req, res) => {
    const tempPath = req.file.path;
    const targetPath = path.join(__dirname, "./uploads/image.png");

    if (path.extname(req.file.originalname).toLowerCase() === ".png") {
      fs.rename(tempPath, targetPath, err => {
        if (err) return handleError(err, res);

        res
          .status(200)
          .contentType("text/plain")
          .end("File uploaded!");
      });
    } else {
      fs.unlink(tempPath, err => {
        if (err) return handleError(err, res);

        res
          .status(403)
          .contentType("text/plain")
          .end("Only .png files are allowed!");
      });
    }
  }
);

In the example above, .png files posted to /upload will be saved to uploaded directory relative to where the script is located.

In order to show the uploaded image, assuming you already have an HTML page containing an img element:

<img src="/image.png" />

you can define another route in your express app and use res.sendFile to serve the stored image:

app.get("/image.png", (req, res) => {
  res.sendFile(path.join(__dirname, "./uploads/image.png"));
});

Query to list all users of a certain group

memberOf (in AD) is stored as a list of distinguishedNames. Your filter needs to be something like:

(&(objectCategory=user)(memberOf=cn=MyCustomGroup,ou=ouOfGroup,dc=subdomain,dc=domain,dc=com))

If you don't yet have the distinguished name, you can search for it with:

(&(objectCategory=group)(cn=myCustomGroup))

and return the attribute distinguishedName. Case may matter.

PHP: How to get referrer URL?

$_SERVER['HTTP_REFERER'] will give you the referrer page's URL if there exists any. If users use a bookmark or directly visit your site by manually typing in the URL, http_referer will be empty. Also if the users are posting to your page programatically (CURL) then they're not obliged to set the http_referer as well. You're missing all _, is that a typo?

How to get thread id of a pthread in linux c program?

You can also write in this manner and it does the same. For eg:

for(int i=0;i < total; i++)
{
    pthread_join(pth[i],NULL);
    cout << "SUM of thread id " << pth[i] << " is " << args[i].sum << endl;
}

This program sets up an array of pthread_t and calculate sum on each. So it is printing the sum of each thread with thread id.

How to prevent form resubmission when page is refreshed (F5 / CTRL+R)

Just redirect it to the same page after making the use of form data, and it works. I have tried it.

header('location:yourpage.php');

Array Index Out of Bounds Exception (Java)

for ( i = 0; i < total.length; i++ ); // remove this
{
    if (total[i]!=0)
        System.out.println( "Letter" + (char)( 'a' + i) + " count =" + total[i]);
}

The for loop loops until i=26 (where 26 is total.length) and then your if is executed, going over the bounds of the array. Remove the ; at the end of the for loop.

Entity Framework: One Database, Multiple DbContexts. Is this a bad idea?

Inspired by [@JulieLerman 's DDD MSDN Mag Article 2013][1]

    public class ShippingContext : BaseContext<ShippingContext>
{
  public DbSet<Shipment> Shipments { get; set; }
  public DbSet<Shipper> Shippers { get; set; }
  public DbSet<OrderShippingDetail> Order { get; set; } //Orders table
  public DbSet<ItemToBeShipped> ItemsToBeShipped { get; set; }
  protected override void OnModelCreating(DbModelBuilder modelBuilder)
  {
    modelBuilder.Ignore<LineItem>();
    modelBuilder.Ignore<Order>();
    modelBuilder.Configurations.Add(new ShippingAddressMap());
  }
}

public class BaseContext<TContext>
  DbContext where TContext : DbContext
{
  static BaseContext()
  {
    Database.SetInitializer<TContext>(null);
  }
  protected BaseContext() : base("DPSalesDatabase")
  {}
}

"If you’re doing new development and you want to let Code First create or migrate your database based on your classes, you’ll need to create an “uber-model” using a DbContext that includes all of the classes and relationships needed to build a complete model that represents the database. However, this context must not inherit from BaseContext." JL

Javascript reduce on array of objects

I did it in ES6 with a little improvement:

arr.reduce((a, b) => ({x: a.x + b.x})).x

return number

Self Join to get employee manager name

   SELECT b.Emp_id, b.Emp_name,e.emp_id as managerID, e.emp_name as managerName
    FROM Employee b
    JOIN Employee e ON b.Emp_ID = e.emp_mgr_id

Try this, it's a JOIN on itself to get the manager :)

How to do a GitHub pull request

I followed tim peterson's instructions but I created a local branch for my changes. However, after pushing I was not seeing the new branch in GitHub. The solution was to add -u to the push command:

git push -u origin <branch>

Adding and removing style attribute from div with jquery

The easy way to handle this (and best HTML solution to boot) is to set up classes that have the styles you want to use. Then it's a simple matter of using addClass() and removeClass(), or even toggleClass().

$('#voltaic_holder').addClass('shiny').removeClass('dull');

or even

$('#voltaic_holder').toggleClass('shiny dull');

Adding files to java classpath at runtime

You can only add folders or jar files to a class loader. So if you have a single class file, you need to put it into the appropriate folder structure first.

Here is a rather ugly hack that adds to the SystemClassLoader at runtime:

import java.io.IOException;
import java.io.File;
import java.net.URLClassLoader;
import java.net.URL;
import java.lang.reflect.Method;

public class ClassPathHacker {

  private static final Class[] parameters = new Class[]{URL.class};

  public static void addFile(String s) throws IOException {
    File f = new File(s);
    addFile(f);
  }//end method

  public static void addFile(File f) throws IOException {
    addURL(f.toURL());
  }//end method


  public static void addURL(URL u) throws IOException {

    URLClassLoader sysloader = (URLClassLoader) ClassLoader.getSystemClassLoader();
    Class sysclass = URLClassLoader.class;

    try {
      Method method = sysclass.getDeclaredMethod("addURL", parameters);
      method.setAccessible(true);
      method.invoke(sysloader, new Object[]{u});
    } catch (Throwable t) {
      t.printStackTrace();
      throw new IOException("Error, could not add URL to system classloader");
    }//end try catch

   }//end method

}//end class

The reflection is necessary to access the protected method addURL. This could fail if there is a SecurityManager.

What exactly does the T and Z mean in timestamp?

The T doesn't really stand for anything. It is just the separator that the ISO 8601 combined date-time format requires. You can read it as an abbreviation for Time.

The Z stands for the Zero timezone, as it is offset by 0 from the Coordinated Universal Time (UTC).

Both characters are just static letters in the format, which is why they are not documented by the datetime.strftime() method. You could have used Q or M or Monty Python and the method would have returned them unchanged as well; the method only looks for patterns starting with % to replace those with information from the datetime object.

Remove HTML Tags in Javascript with Regex

For a proper HTML sanitizer in JS, see http://code.google.com/p/google-caja/wiki/JsHtmlSanitizer

What is default color for text in textview?

I know it is old but according to my own theme editor with default light theme, default

textPrimaryColor = #000000

and

textColorPrimaryDark = #757575

How to include CSS file in Symfony 2 and Twig?

You are doing everything right, except passing your bundle path to asset() function.

According to documentation - in your example this should look like below:

{{ asset('bundles/webshome/css/main.css') }}

Tip: you also can call assets:install with --symlink key, so it will create symlinks in web folder. This is extremely useful when you often apply js or css changes (in this way your changes, applied to src/YouBundle/Resources/public will be immediately reflected in web folder without need to call assets:install again):

app/console assets:install web --symlink

Also, if you wish to add some assets in your child template, you could call parent() method for the Twig block. In your case it would be like this:

{% block stylesheets %}
    {{ parent() }}

    <link href="{{ asset('bundles/webshome/css/main.css') }}" rel="stylesheet">
{% endblock %}

Split string into tokens and save them in an array

Why `strtok()` is a bad idea

Do not use strtok() in normal code, strtok() uses static variables which have some problems. There are some use cases on embedded microcontrollers where static variables make sense but avoid them in most other cases. strtok() behaves unexpected when more than 1 thread uses it, when it is used in a interrupt or when there are some other circumstances where more than one input is processed between successive calls to strtok(). Consider this example:

#include <stdio.h>
#include <string.h>

//Splits the input by the / character and prints the content in between
//the / character. The input string will be changed
void printContent(char *input)
{
    char *p = strtok(input, "/");
    while(p)
    {
        printf("%s, ",p);
        p = strtok(NULL, "/");
    }
}

int main(void)
{
    char buffer[] = "abc/def/ghi:ABC/DEF/GHI";
    char *p = strtok(buffer, ":");
    while(p)
    {
        printContent(p);
        puts(""); //print newline
        p = strtok(NULL, ":");
    }
    return 0;
}

You may expect the output:

abc, def, ghi,
ABC, DEF, GHI,

But you will get

abc, def, ghi,

This is because you call strtok() in printContent() resting the internal state of strtok() generated in main(). After returning, the content of strtok() is empty and the next call to strtok() returns NULL.

What you should do instead

You could use strtok_r() when you use a POSIX system, this versions does not need static variables. If your library does not provide strtok_r() you can write your own version of it. This should not be hard and Stackoverflow is not a coding service, you can write it on your own.

Jenkins restrict view of jobs per user

As mentioned above by Vadim Use Jenkins "Project-based Matrix Authorization Strategy" under "Manage Jenkins" => "Configure System". Don't forget to add your admin user there and give all permissions. Now add the restricted user there and give overall read access. Then go to the configuration page of each project, you now have "Enable project-based security" option. Now add each user you want to authorize.

What is the difference between declarations, providers, and import in NgModule?

Angular Concepts

imports makes the exported declarations of other modules available in the current module
declarations are to make directives (including components and pipes) from the current module available to other directives in the current module. Selectors of directives, components or pipes are only matched against the HTML if they are declared or imported.
providers are to make services and values known to DI (dependency injection). They are added to the root scope and they are injected to other services or directives that have them as dependency.

A special case for providers are lazy loaded modules that get their own child injector. providers of a lazy loaded module are only provided to this lazy loaded module by default (not the whole application as it is with other modules).

For more details about modules see also https://angular.io/docs/ts/latest/guide/ngmodule.html

exports makes the components, directives, and pipes available in modules that add this module to imports. exports can also be used to re-export modules such as CommonModule and FormsModule, which is often done in shared modules.
entryComponents registers components for offline compilation so that they can be used with ViewContainerRef.createComponent(). Components used in router configurations are added implicitly.

TypeScript (ES2015) imports

import ... from 'foo/bar' (which may resolve to an index.ts) are for TypeScript imports. You need these whenever you use an identifier in a typescript file that is declared in another typescript file.

Angular's @NgModule() imports and TypeScript import are entirely different concepts.

Most of them are actually plain ECMAScript 2015 (ES6) module syntax that TypeScript uses as well.

How can I profile C++ code running on Linux?

I assume you're using GCC. The standard solution would be to profile with gprof.

Be sure to add -pg to compilation before profiling:

cc -o myprog myprog.c utils.c -g -pg

I haven't tried it yet but I've heard good things about google-perftools. It is definitely worth a try.

How to use SVG markers in Google Maps API v3

Things are going better, right now you can use SVG files.

        marker = new google.maps.Marker({
            position: {lat: 36.720426, lng: -4.412573},
            map: map,
            draggable: true,
            icon: "img/tree.svg"
        });

Sending HTML Code Through JSON

All these answers didn't work for me.

But this one did:

json_encode($array, JSON_HEX_QUOT | JSON_HEX_TAG);

Thanks to this answer.

Can someone post a well formed crossdomain.xml sample?

If you're using webservices, you'll also need the 'allow-http-request-headers-from' element. Here's our default, development, 'allow everything' policy.

<?xml version="1.0" ?>
<cross-domain-policy>
  <site-control permitted-cross-domain-policies="master-only"/>
  <allow-access-from domain="*"/>
  <allow-http-request-headers-from domain="*" headers="*"/>
</cross-domain-policy>

How to create a folder with name as current date in batch (.bat) files

the expression %date:~p,n% returns n number of characters from position p in the date string.

if my system date string is Mon23/11/2015

the command %date:~1,3% returns the value Mon

the command %date:~10,4% returns the value 2015

and in conjunction with the md (or mkdir) command

the command md %date:~10,4%%date:~7,2%%date:~4,2% makes a directory named 20151123

likewise if your date string in in the format Monday, 23/Nov/2015

the command md %date:~16,4%%date:~12,3%%date:~9,2% makes a directory named 2015Nov23

If you accidentally return characters from the date string that are not allowed in folder names or use invalid values for p and n you will get an error. Additionally if you return values that include \ this may create a folder within a folder.

What is ANSI format?

ASCII just defines a 7 bit code page with 128 symbols. ANSI extends this to 8 bit and there are several different code pages for the symbols 128 to 255.

The naming ANSI is not correct because it is actually the ISO/IEC 8859 norm that defines this code pages. See ISO/IEC 8859 for reference. There are 16 code pages ISO/IEC 8859-1 to ISO/IEC 8859-16.

Windows-1252 is again based on ISO/IEC 8859-1 with some modification mainly in the range of the C1 control set in the range 128 to 159. Wikipedia states that Windows-1252 is also refered as ISO-8859-1 with a second hyphen between ISO and 8859. (Unbelievable! Who does something like that?!?)

Connection string with relative path to the database file

Would you please try with below code block, which is exactly what you're looking for:

SqlConnection conn = new SqlConnection
{
    ConnectionString = "Data Source=" + System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase) + "\\Database.sdf"
};

npm command to uninstall or prune unused packages in Node.js

If you're not worried about a couple minutes time to do so, a solution would be to rm -rf node_modules and npm install again to rebuild the local modules.

calling parent class method from child class object in java

NOTE calling parent method via super will only work on parent class, If your parent is interface, and wants to call the default methods then need to add interfaceName before super like IfscName.super.method();

interface Vehicle {
    //Non abstract method
    public default void printVehicleTypeName() { //default keyword can be used only in interface.
        System.out.println("Vehicle");
    }
}


class FordFigo extends FordImpl implements Vehicle, Ford {
    @Override
    public void printVehicleTypeName() { 
        System.out.println("Figo");
        Vehicle.super.printVehicleTypeName();
    }
}

Interface name is needed because same default methods can be available in multiple interface name that this class extends. So explicit call to a method is required.

Best way to convert string to bytes in Python 3?

Answer for a slightly different problem:

You have a sequence of raw unicode that was saved into a str variable:

s_str: str = "\x00\x01\x00\xc0\x01\x00\x00\x00\x04"

You need to be able to get the byte literal of that unicode (for struct.unpack(), etc.)

s_bytes: bytes = b'\x00\x01\x00\xc0\x01\x00\x00\x00\x04'

Solution:

s_new: bytes = bytes(s, encoding="raw_unicode_escape")

Reference (scroll up for standard encodings):

Python Specific Encodings

Javascript equivalent of php's strtotime()?

I jealous the strtotime() in php, but I do mine in javascript using moment. Not as sweet as that from php, but does the trick neatly too.

// first day of the month
var firstDayThisMonth = moment(firstDayThisMonth).startOf('month').toDate();

Go back and forth using the subtract() and add() with the endOf() and startOf():

// last day of previous month
var yesterMonthLastDay = moment(yesterMonthLastDay).subtract(1,'months').endOf('month').toDate();

bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

Instead of using lxml use html.parser, you can use this piece of code:

soup = BeautifulSoup(html, 'html.parser')

Get Root Directory Path of a PHP project

For PHP >= 5.3.0 try

PHP magic constants.

__DIR__

And make your path relative.

For PHP < 5.3.0 try

dirname(__FILE__)

Javascript: 'window' is not defined

The window object represents an open window in a browser. Since you are not running your code within a browser, but via Windows Script Host, the interpreter won't be able to find the window object, since it does not exist, since you're not within a web browser.

What does "pending" mean for request in Chrome Developer Window?

In my case, there's an update for Chrome that makes it won't load before you restart the browser. Cheers

How do I create a user with the same privileges as root in MySQL/MariaDB?

% mysql --user=root mysql
CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost' WITH GRANT OPTION;
CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%' WITH GRANT OPTION;
CREATE USER 'admin'@'localhost';
GRANT RELOAD,PROCESS ON *.* TO 'admin'@'localhost';
CREATE USER 'dummy'@'localhost';
FLUSH PRIVILEGES;

How do I activate a specific workbook and a specific sheet?

You can try this.

Workbooks("Tire.xls").Activate

ThisWorkbook.Sheets("Sheet1").Select
Cells(2,24).value=24

How to convert a plain object into an ES6 Map?

const myMap = new Map(
    Object
        .keys(myObj)
        .map(
            key => [key, myObj[key]]
        )
)

How to remove the left part of a string?

Why not using regex with escape? ^ matches the initial part of a line and re.MULTILINE matches on each line. re.escape ensures that the matching is exact.

>>> print(re.sub('^' + re.escape('path='), repl='', string='path=c:\path\nd:\path2', flags=re.MULTILINE))
c:\path
d:\path2

How could others, on a local network, access my NodeJS app while it's running on my machine?

Make sure the server is running, either by using 'npm start', or 'nodemon' in the command line window.

Git: "please tell me who you are" error

Update your bootstrap process to create a ${HOME}/.gitconfig with the proper contents, or to copy an existing one from somewhere.

How to redirect page after click on Ok button on sweet alert?

Existing answers did not work for me i just used $('.confirm').hide(). and it worked for me.

success: function(res) {
$('.confirm').hide()
swal("Deleted!", "Successfully deleted", "success")
setTimeout(function(){
window.location = res.redirect_url;
},700);

Forbidden You don't have permission to access /wp-login.php on this server

I got recently this error and i used the solution which is proposed by @SirPaul. But the error was existing on the other configuration pages of the WordPress like update-core.php .

The solution that i have found, which resolved all the permission problems, was to deactivate iThemes Security plugin and update it and reactivate it.

How to generate JAXB classes from XSD?

Download http://java.net/downloads/jaxb-workshop/IDE%20plugins/org.jvnet.jaxbw.zip
Extract the zip file .
Place the org.jvnet.jaxbw.eclipse_1.0.0 folder into .eclipse\plugins folder
Restart the eclipse.
Right click on XSD file and you can find contect menu. JAXB 2.0 -> Run XJC .

How to copy a row and insert in same table with a autoincrement field in MySQL?

insert into MyTable(field1, field2, id_backup)
    select field1, field2, uniqueId from MyTable where uniqueId = @Id;

Should methods in a Java interface be declared with or without a public access modifier?

I used declare methods with the public modifier, because it makes the code more readable, especially with syntax highlighting. In our latest project though, we used Checkstyle which shows a warning with the default configuration for public modifiers on interface methods, so I switched to ommitting them.

So I'm not really sure what's best, but one thing I really don't like is using public abstract on interface methods. Eclipse does this sometimes when refactoring with "Extract Interface".

How to use moment.js library in angular 2 typescript app?

To use it in a Typescript project you will need to install moment:

npm install moment --save

After installing moment, you can use it in any .ts file after importing it:

import * as moment from "moment";

Unit Testing C Code

I didn't get far testing a legacy C application before I started looking for a way to mock functions. I needed mocks badly to isolate the C file I want to test from others. I gave cmock a try and I think I will adopt it.

Cmock scans header files and generates mock functions based on prototypes it finds. Mocks will allow you to test a C file in perfect isolation. All you will have to do is to link your test file with mocks instead of your real object files.

Another advantage of cmock is that it will validate parameters passed to mocked functions, and it will let you specify what return value the mocks should provide. This is very useful to test different flows of execution in your functions.

Tests consist of the typical testA(), testB() functions in which you build expectations, call functions to test and check asserts.

The last step is to generate a runner for your tests with unity. Cmock is tied to the unity test framework. Unity is as easy to learn as any other unit test framework.

Well worth a try and quite easy to grasp:

http://sourceforge.net/apps/trac/cmock/wiki

Update 1

Another framework I am investigating is Cmockery.

http://code.google.com/p/cmockery/

It is a pure C framework supporting unit testing and mocking. It has no dependency on ruby (contrary to Cmock) and it has very little dependency on external libs.

It requires a bit more manual work to setup mocks because it does no code generation. That does not represent a lot of work for an existing project since prototypes won't change much: once you have your mocks, you won't need to change them for a while (this is my case). Extra typing provides complete control of mocks. If there is something you don't like, you simply change your mock.

No need of a special test runner. You only need need to create an array of tests and pass it to a run_tests function. A bit more manual work here too but I definitely like the idea of a self-contained autonomous framework.

Plus it contains some nifty C tricks I didn't know.

Overall Cmockery needs a bit more understanding of mocks to get started. Examples should help you overcome this. It looks like it can do the job with simpler mechanics.

How does OkHttp get Json string?

Below code is for getting data from online server using GET method and okHTTP library for android kotlin...

Log.e("Main",response.body!!.string())

in above line !! is the thing using which you can get the json from response body

val client = OkHttpClient()
            val request: Request = Request.Builder()
                .get()
                .url("http://172.16.10.126:8789/test/path/jsonpage")
                .addHeader("", "")
                .addHeader("", "")
                .build()
            client.newCall(request).enqueue(object : Callback {
                override fun onFailure(call: Call, e: IOException) {
                    // Handle this
                    Log.e("Main","Try again latter!!!")
                }

                override fun onResponse(call: Call, response: Response) {
                    // Handle this
                    Log.e("Main",response.body!!.string())
                }
            })

Utils to read resource text file to String (Java)

I made NO-dependency static method like this:

import java.nio.file.Files;
import java.nio.file.Paths;

public class ResourceReader {
    public  static String asString(String resourceFIleName) {
        try  {
            return new String(Files.readAllBytes(Paths.get(new CheatClassLoaderDummyClass().getClass().getClassLoader().getResource(resourceFIleName).toURI())));
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}
class CheatClassLoaderDummyClass{//cheat class loader - for sql file loading
}

How to change the output color of echo in Linux

I instead of hard coding escape codes that are specific to your current terminal, you should use tput.

This is my favorite demo script:

#!/bin/bash

tput init

end=$(( $(tput colors)-1 ))
w=8
for c in $(seq 0 $end); do
    eval "$(printf "tput setaf %3s   " "$c")"; echo -n "$_"
    [[ $c -ge $(( w*2 )) ]] && offset=2 || offset=0
    [[ $(((c+offset) % (w-offset))) -eq $(((w-offset)-1)) ]] && echo
done

tput init

Temporarily disable all foreign key constraints

Truncating the table wont be possible even if you disable the foreign keys.so you can use delete command to remove all the records from the table,but be aware if you are using delete command for a table which consists of millions of records then your package will be slow and your transaction log size will increase and it may fill up your valuable disk space.

If you drop the constraints it may happen that you will fill up your table with unclean data and when you try to recreate the constraints it may not allow you to as it will give errors. so make sure that if you drop the constraints,you are loading data which are correctly related to each other and satisfy the constraint relations which you are going to recreate.

so please carefully think the pros and cons of each method and use it according to your requirements

AddTransient, AddScoped and AddSingleton Services Differences

TL;DR

Transient objects are always different; a new instance is provided to every controller and every service.

Scoped objects are the same within a request, but different across different requests.

Singleton objects are the same for every object and every request.

For more clarification, this example from .NET documentation shows the difference:

To demonstrate the difference between these lifetime and registration options, consider a simple interface that represents one or more tasks as an operation with a unique identifier, OperationId. Depending on how we configure the lifetime for this service, the container will provide either the same or different instances of the service to the requesting class. To make it clear which lifetime is being requested, we will create one type per lifetime option:

using System;

namespace DependencyInjectionSample.Interfaces
{
    public interface IOperation
    {
        Guid OperationId { get; }
    }

    public interface IOperationTransient : IOperation
    {
    }

    public interface IOperationScoped : IOperation
    {
    }

    public interface IOperationSingleton : IOperation
    {
    }

    public interface IOperationSingletonInstance : IOperation
    {
    }
}

We implement these interfaces using a single class, Operation, that accepts a GUID in its constructor, or uses a new GUID if none is provided:

using System;
using DependencyInjectionSample.Interfaces;
namespace DependencyInjectionSample.Classes
{
    public class Operation : IOperationTransient, IOperationScoped, IOperationSingleton, IOperationSingletonInstance
    {
        Guid _guid;
        public Operation() : this(Guid.NewGuid())
        {

        }

        public Operation(Guid guid)
        {
            _guid = guid;
        }

        public Guid OperationId => _guid;
    }
}

Next, in ConfigureServices, each type is added to the container according to its named lifetime:

services.AddTransient<IOperationTransient, Operation>();
services.AddScoped<IOperationScoped, Operation>();
services.AddSingleton<IOperationSingleton, Operation>();
services.AddSingleton<IOperationSingletonInstance>(new Operation(Guid.Empty));
services.AddTransient<OperationService, OperationService>();

Note that the IOperationSingletonInstance service is using a specific instance with a known ID of Guid.Empty, so it will be clear when this type is in use. We have also registered an OperationService that depends on each of the other Operation types, so that it will be clear within a request whether this service is getting the same instance as the controller, or a new one, for each operation type. All this service does is expose its dependencies as properties, so they can be displayed in the view.

using DependencyInjectionSample.Interfaces;

namespace DependencyInjectionSample.Services
{
    public class OperationService
    {
        public IOperationTransient TransientOperation { get; }
        public IOperationScoped ScopedOperation { get; }
        public IOperationSingleton SingletonOperation { get; }
        public IOperationSingletonInstance SingletonInstanceOperation { get; }

        public OperationService(IOperationTransient transientOperation,
            IOperationScoped scopedOperation,
            IOperationSingleton singletonOperation,
            IOperationSingletonInstance instanceOperation)
        {
            TransientOperation = transientOperation;
            ScopedOperation = scopedOperation;
            SingletonOperation = singletonOperation;
            SingletonInstanceOperation = instanceOperation;
        }
    }
}

To demonstrate the object lifetimes within and between separate individual requests to the application, the sample includes an OperationsController that requests each kind of IOperation type as well as an OperationService. The Index action then displays all of the controller’s and service’s OperationId values.

using DependencyInjectionSample.Interfaces;
using DependencyInjectionSample.Services;
using Microsoft.AspNetCore.Mvc;

namespace DependencyInjectionSample.Controllers
{
    public class OperationsController : Controller
    {
        private readonly OperationService _operationService;
        private readonly IOperationTransient _transientOperation;
        private readonly IOperationScoped _scopedOperation;
        private readonly IOperationSingleton _singletonOperation;
        private readonly IOperationSingletonInstance _singletonInstanceOperation;

        public OperationsController(OperationService operationService,
            IOperationTransient transientOperation,
            IOperationScoped scopedOperation,
            IOperationSingleton singletonOperation,
            IOperationSingletonInstance singletonInstanceOperation)
        {
            _operationService = operationService;
            _transientOperation = transientOperation;
            _scopedOperation = scopedOperation;
            _singletonOperation = singletonOperation;
            _singletonInstanceOperation = singletonInstanceOperation;
        }

        public IActionResult Index()
        {
            // ViewBag contains controller-requested services
            ViewBag.Transient = _transientOperation;
            ViewBag.Scoped = _scopedOperation;
            ViewBag.Singleton = _singletonOperation;
            ViewBag.SingletonInstance = _singletonInstanceOperation;

            // Operation service has its own requested services
            ViewBag.Service = _operationService;
            return View();
        }
    }
}

Now two separate requests are made to this controller action:

Observe which of the OperationId values varies within a request, and between requests.

Transient objects are always different; a new instance is provided to every controller and every service.
Scoped objects are the same within a request, but different across different requests
Singleton objects are the same for every object and every request (regardless of whether an instance is provided in ConfigureServices)

Twitter bootstrap 3 two columns full height

Pure CSS solution

Working Fiddle

Using CSS2.1 only, Work with all browsers (IE8+), without specifying any height or width.

That means that if your header suddenly grows longer, or your left navigation needs to enlarge, you don't have to fix anything in your CSS.

Totally responsive, simple & clear and very easy to manage.

<div class="Container">
    <div class="Header">
    </div>
    <div class="HeightTaker">
        <div class="Wrapper">
            <div class="LeftNavigation">
            </div>
            <div class="Content">
            </div>
        </div>
    </div>
</div>

Explanation: The container div takes 100% height of the body, and he's divided into 2 sections. The header section will span to its needed height, and the HeightTaker will take the rest. How is it achieved? by floating an empty element along side the container with 100% height (using :before), and giving the HeightTaker an empty element at the end with the clear rule (using :after). that element cant be in the same line with the floated element, so he's pushed till the end. which is exactly the 100% of the document.

With that we make the HeightTaker span the rest of the container height, without stating any specific height/ margin.

inside that HeightTaker we build a normal floated layout (to achieve the column like display) with a minor change.. we have a Wrapper element, that is needed for the 100% height to work.

Update

Here's the Demo with Bootstrap classes. (I just added one div to your layout)

How to pass variables from one php page to another without form?

use the get method in the url. If you want to pass over a variable called 'phone' as 0001112222:

<a href='whatever.php?phone=0001112222'>click</a>

then on the next page (whatever.php) you can access this var via:

$_GET['phone']

How to execute .sql script file using JDBC

This link might help you out: http://pastebin.com/f10584951.

Pasted below for posterity:

/*
 * Slightly modified version of the com.ibatis.common.jdbc.ScriptRunner class
 * from the iBATIS Apache project. Only removed dependency on Resource class
 * and a constructor
 */
/*
 *  Copyright 2004 Clinton Begin
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

import java.io.IOException;
import java.io.LineNumberReader;
import java.io.PrintWriter;
import java.io.Reader;
import java.sql.*;

/**
 * Tool to run database scripts
 */
public class ScriptRunner {

    private static final String DEFAULT_DELIMITER = ";";

    private Connection connection;

    private boolean stopOnError;
    private boolean autoCommit;

    private PrintWriter logWriter = new PrintWriter(System.out);
    private PrintWriter errorLogWriter = new PrintWriter(System.err);

    private String delimiter = DEFAULT_DELIMITER;
    private boolean fullLineDelimiter = false;

    /**
     * Default constructor
     */
    public ScriptRunner(Connection connection, boolean autoCommit,
            boolean stopOnError) {
        this.connection = connection;
        this.autoCommit = autoCommit;
        this.stopOnError = stopOnError;
    }

    public void setDelimiter(String delimiter, boolean fullLineDelimiter) {
        this.delimiter = delimiter;
        this.fullLineDelimiter = fullLineDelimiter;
    }

    /**
     * Setter for logWriter property
     *
     * @param logWriter
     *            - the new value of the logWriter property
     */
    public void setLogWriter(PrintWriter logWriter) {
        this.logWriter = logWriter;
    }

    /**
     * Setter for errorLogWriter property
     *
     * @param errorLogWriter
     *            - the new value of the errorLogWriter property
     */
    public void setErrorLogWriter(PrintWriter errorLogWriter) {
        this.errorLogWriter = errorLogWriter;
    }

    /**
     * Runs an SQL script (read in using the Reader parameter)
     *
     * @param reader
     *            - the source of the script
     */
    public void runScript(Reader reader) throws IOException, SQLException {
        try {
            boolean originalAutoCommit = connection.getAutoCommit();
            try {
                if (originalAutoCommit != this.autoCommit) {
                    connection.setAutoCommit(this.autoCommit);
                }
                runScript(connection, reader);
            } finally {
                connection.setAutoCommit(originalAutoCommit);
            }
        } catch (IOException e) {
            throw e;
        } catch (SQLException e) {
            throw e;
        } catch (Exception e) {
            throw new RuntimeException("Error running script.  Cause: " + e, e);
        }
    }

    /**
     * Runs an SQL script (read in using the Reader parameter) using the
     * connection passed in
     *
     * @param conn
     *            - the connection to use for the script
     * @param reader
     *            - the source of the script
     * @throws SQLException
     *             if any SQL errors occur
     * @throws IOException
     *             if there is an error reading from the Reader
     */
    private void runScript(Connection conn, Reader reader) throws IOException,
            SQLException {
        StringBuffer command = null;
        try {
            LineNumberReader lineReader = new LineNumberReader(reader);
            String line = null;
            while ((line = lineReader.readLine()) != null) {
                if (command == null) {
                    command = new StringBuffer();
                }
                String trimmedLine = line.trim();
                if (trimmedLine.startsWith("--")) {
                    println(trimmedLine);
                } else if (trimmedLine.length() < 1
                        || trimmedLine.startsWith("//")) {
                    // Do nothing
                } else if (trimmedLine.length() < 1
                        || trimmedLine.startsWith("--")) {
                    // Do nothing
                } else if (!fullLineDelimiter
                        && trimmedLine.endsWith(getDelimiter())
                        || fullLineDelimiter
                        && trimmedLine.equals(getDelimiter())) {
                    command.append(line.substring(0, line
                            .lastIndexOf(getDelimiter())));
                    command.append(" ");
                    Statement statement = conn.createStatement();

                    println(command);

                    boolean hasResults = false;
                    if (stopOnError) {
                        hasResults = statement.execute(command.toString());
                    } else {
                        try {
                            statement.execute(command.toString());
                        } catch (SQLException e) {
                            e.fillInStackTrace();
                            printlnError("Error executing: " + command);
                            printlnError(e);
                        }
                    }

                    if (autoCommit && !conn.getAutoCommit()) {
                        conn.commit();
                    }

                    ResultSet rs = statement.getResultSet();
                    if (hasResults && rs != null) {
                        ResultSetMetaData md = rs.getMetaData();
                        int cols = md.getColumnCount();
                        for (int i = 0; i < cols; i++) {
                            String name = md.getColumnLabel(i);
                            print(name + "\t");
                        }
                        println("");
                        while (rs.next()) {
                            for (int i = 0; i < cols; i++) {
                                String value = rs.getString(i);
                                print(value + "\t");
                            }
                            println("");
                        }
                    }

                    command = null;
                    try {
                        statement.close();
                    } catch (Exception e) {
                        // Ignore to workaround a bug in Jakarta DBCP
                    }
                    Thread.yield();
                } else {
                    command.append(line);
                    command.append(" ");
                }
            }
            if (!autoCommit) {
                conn.commit();
            }
        } catch (SQLException e) {
            e.fillInStackTrace();
            printlnError("Error executing: " + command);
            printlnError(e);
            throw e;
        } catch (IOException e) {
            e.fillInStackTrace();
            printlnError("Error executing: " + command);
            printlnError(e);
            throw e;
        } finally {
            conn.rollback();
            flush();
        }
    }

    private String getDelimiter() {
        return delimiter;
    }

    private void print(Object o) {
        if (logWriter != null) {
            System.out.print(o);
        }
    }

    private void println(Object o) {
        if (logWriter != null) {
            logWriter.println(o);
        }
    }

    private void printlnError(Object o) {
        if (errorLogWriter != null) {
            errorLogWriter.println(o);
        }
    }

    private void flush() {
        if (logWriter != null) {
            logWriter.flush();
        }
        if (errorLogWriter != null) {
            errorLogWriter.flush();
        }
    }
}

mysql_fetch_array() expects parameter 1 to be resource problem

You are not doing error checking after the call to mysql_query:

$result = mysql_query("SELECT * FROM student WHERE IDNO=".$_GET['id']);
if (!$result) { // add this check.
    die('Invalid query: ' . mysql_error());
}

In case mysql_query fails, it returns false, a boolean value. When you pass this to mysql_fetch_array function (which expects a mysql result object) we get this error.

PHP7 : install ext-dom issue

sudo apt install php-xml will work but the thing is it will download the plugin for the latest PHP version.

If your PHP version is not the latest, then you can add version in it:

# PHP 7.1
sudo apt install php7.1-xml

# PHP 7.2:
sudo apt install php7.2-xml

# PHP 7.3
sudo apt install php7.3-xml


# PHP 7.4
sudo apt install php7.4-xml

# PHP 8
sudo apt install php-xml

XML Serialize generic list of serializable objects

knowTypeList parameter let serialize with DataContractSerializer several known types:

private static void WriteObject(
        string fileName, IEnumerable<Vehichle> reflectedInstances, List<Type> knownTypeList)
    {
        using (FileStream writer = new FileStream(fileName, FileMode.Append))
        {
            foreach (var item in reflectedInstances)
            {
                var serializer = new DataContractSerializer(typeof(Vehichle), knownTypeList);
                serializer.WriteObject(writer, item);
            }
        }
    }

Plotting with C#

See Samples Environment for Microsoft Chart Controls:

The samples environment for Microsoft Chart Controls for .NET Framework contains over 200 samples for both ASP.NET and Windows Forms. The samples cover every major feature in Chart Controls for .NET Framework. They enable you to see the Chart controls in action as well as use the code as templates for your own web and windows applications.

Seems to be more business oriented, but may be of some value to science students and scientists.

How can I capitalize the first letter of each word in a string using JavaScript?

Here I used the replace() function.

function titleCase(str){
    return str.replace(/\w\S*/g, function(txt){return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();});
}

Freely convert between List<T> and IEnumerable<T>

To prevent duplication in memory, resharper is suggesting this:

List<string> myList = new List<string>();
IEnumerable<string> myEnumerable = myList;
List<string> listAgain = myList as List<string>() ?? myEnumerable.ToList();

.ToList() returns a new immutable list. So changes to listAgain does not effect myList in @Tamas Czinege answer. This is correct in most instances for least two reasons: This helps prevent changes in one area effecting the other area (loose coupling), and it is very readable, since we shouldn't be designing code with compiler concerns.

But there are certain instances, like being in a tight loop or working on an embedded or low memory system, where compiler considerations should be taken into consideration.

What is "pom" packaging in maven?

pom packaging is simply a specification that states the primary artifact is not a war or jar, but the pom.xml itself.

Often it is used in conjunction with "modules" which are typically contained in sub-directories of the project in question; however, it may also be used in certain scenarios where no primary binary was meant to be built, all the other important artifacts have been declared as secondary artifacts

Think of a "documentation" project, the primary artifact might be a PDF, but it's already built, and the work to declare it as a secondary artifact might be desired over the configuration to tell maven how to build a PDF that doesn't need compiled.

How do I order my SQLITE database in descending order, for an android app?

you can do it with this

Cursor cursor = database.query(
            TABLE_NAME,
            YOUR_COLUMNS, null, null, null, null, COLUMN_INTEREST+" DESC");

(grep) Regex to match non-ASCII characters?

[^\x00-\x7F] and [^[:ascii:]] miss some control bytes so strings can be the better option sometimes. For example cat test.torrent | perl -pe 's/[^[:ascii:]]+/\n/g' will do odd things to your terminal, where as strings test.torrent will behave.

How to Save Console.WriteLine Output to Text File

For the question:

How to save Console.Writeline Outputs to text file?

I would use Console.SetOut as others have mentioned.

However, it looks more like you are keeping track of your program flow. I would consider using Debug or Trace for keeping track of the program state.

It works similar the console except you have more control over your input such as WriteLineIf.

Debug will only operate when in debug mode where as Trace will operate in both debug or release mode.

They both allow for listeners such as output files or the console.

TextWriterTraceListener tr1 = new TextWriterTraceListener(System.Console.Out);
Debug.Listeners.Add(tr1);

TextWriterTraceListener tr2 = new TextWriterTraceListener(System.IO.File.CreateText("Output.txt"));
Debug.Listeners.Add(tr2);

-http://support.microsoft.com/kb/815788

Import Error: No module named numpy

I'm not sure exactly why I was getting the error, but pip3 uninstall numpy then pip3 install numpy resolved the issue for me.

How to extract string following a pattern with grep, regex or perl

The regular expression would be:

.+name="([^"]+)"

Then the grouping would be in the \1

NPM global install "cannot find module"

Had the same problem on one of the test servers running Ubuntu under root. Then created a new user using useradd -m myuser and installed everything (nvm, node, packages) as myuser. Now it's working fine.

Adding a css class to select using @Html.DropDownList()

You can simply do this:

@Html.DropDownList("PriorityID", null, new { @class="form-control"})

Convert a dta file to csv without Stata software

You could try doing it through R:

For Stata <= 15 you can use the haven package to read the dataset and then you simply write it to external CSV file:

library(haven)
yourData = read_dta("path/to/file")
write.csv(yourData, file = "yourStataFile.csv")

Alternatively, visit the link pointed by huntaub in a comment below.

For Stata <= 12 datasets foreign package can also be used

library(foreign)
yourData <- read.dta("yourStataFile.dta")

difference between $query>num_rows() and $this->db->count_all_results() in CodeIgniter & which one is recommended

Simply as bellow;

$this->db->get('table_name')->num_rows();

This will get number of rows/records. however you can use search parameters as well;

$this->db->select('col1','col2')->where('col'=>'crieterion')->get('table_name')->num_rows();

However, it should be noted that you will see bad bad errors if applying as below;

$this->db->get('table_name')->result()->num_rows();

Python module for converting PDF to text

I needed to convert a specific PDF to plain text within a python module. I used PDFMiner 20110515, after reading through their pdf2txt.py tool I wrote this simple snippet:

from cStringIO import StringIO
from pdfminer.pdfinterp import PDFResourceManager, process_pdf
from pdfminer.converter import TextConverter
from pdfminer.layout import LAParams

def to_txt(pdf_path):
    input_ = file(pdf_path, 'rb')
    output = StringIO()

    manager = PDFResourceManager()
    converter = TextConverter(manager, output, laparams=LAParams())
    process_pdf(manager, converter, input_)

    return output.getvalue()

What does the question mark operator mean in Ruby?

It is a code style convention; it indicates that a method returns a boolean value.

The question mark is a valid character at the end of a method name.

Context.startForegroundService() did not then call Service.startForeground()

I am adding some code in @humazed answer. So there in no initial notification. It might be a workaround but it works for me.

@Override
 public void onCreate() {
        super.onCreate();

        if (Build.VERSION.SDK_INT >= 26) {
            String CHANNEL_ID = "my_channel_01";
            NotificationChannel channel = new NotificationChannel(CHANNEL_ID,
                    "Channel human readable title",
                    NotificationManager.IMPORTANCE_DEFAULT);

            ((NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE)).createNotificationChannel(channel);

            Notification notification = new NotificationCompat.Builder(this, CHANNEL_ID)
                    .setContentTitle("")
                    .setContentText("")
                    .setColor(ContextCompat.getColor(this, R.color.transparentColor))
                    .setSmallIcon(ContextCompat.getColor(this, R.color.transparentColor)).build();

            startForeground(1, notification);
        }
}

I am adding transparentColor in small icon and color on notification. It will work.

SQL Server: What is the difference between CROSS JOIN and FULL OUTER JOIN?

For SQL Server, CROSS JOIN and FULL OUTER JOIN are different. CROSS JOIN is simply Cartesian Product of two tables, irrespective of any filter criteria or any condition.

FULL OUTER JOIN gives unique result set of LEFT OUTER JOIN and RIGHT OUTER JOIN of two tables. It also needs ON clause to map two columns of tables.

Table 1 contains 10 rows and Table 2 contains 20 rows with 5 rows matching on specific columns.

Then CROSS JOIN will return 10*20=200 rows in result set.

FULL OUTER JOIN will return 25 rows in result set.

FULL OUTER JOIN (or any other JOIN) always returns result set with less than or equal to Cartesian Product number.

Number of rows returned by FULL OUTER JOIN equal to (No. of Rows by LEFT OUTER JOIN) + (No. of Rows by RIGHT OUTER JOIN) - (No. of Rows by INNER JOIN).

Moving Panel in Visual Studio Code to right side

"workbench.panel.defaultLocation": "right",

What is the best way to conditionally apply a class?

well i would suggest you to check condition in your controller with a function returning true or false .

<div class="week-wrap" ng-class="{today: getTodayForHighLight(todayDate, day.date)}">{{day.date}}</div>

and in your controller check the condition

$scope.getTodayForHighLight = function(today, date){
return (today == date);
}

How do I use setsockopt(SO_REUSEADDR)?

Depending on the libc release it could be needed to set both SO_REUSEADDR and SO_REUSEPORT socket options as explained in socket(7) documentation :

   SO_REUSEPORT (since Linux 3.9)
          Permits multiple AF_INET or AF_INET6 sockets to be bound to an
          identical socket address.  This option must be set on each
          socket (including the first socket) prior to calling bind(2)
          on the socket.  To prevent port hijacking, all of the
          processes binding to the same address must have the same
          effective UID.  This option can be employed with both TCP and
          UDP sockets.

As this socket option appears with kernel 3.9 and raspberry use 3.12.x, it will be needed to set SO_REUSEPORT.

You can set theses two options before calling bind like this :

    int reuse = 1;
    if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, (const char*)&reuse, sizeof(reuse)) < 0)
        perror("setsockopt(SO_REUSEADDR) failed");

#ifdef SO_REUSEPORT
    if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT, (const char*)&reuse, sizeof(reuse)) < 0) 
        perror("setsockopt(SO_REUSEPORT) failed");
#endif

C++ obtaining milliseconds time on Linux -- clock() doesn't seem to work properly

With C++11 and std::chrono::high_resolution_clock you can do this:

#include <iostream>
#include <chrono>
#include <thread>
typedef std::chrono::high_resolution_clock Clock;

int main()
{
    std::chrono::milliseconds three_milliseconds{3};

    auto t1 = Clock::now();
    std::this_thread::sleep_for(three_milliseconds);
    auto t2 = Clock::now();

    std::cout << "Delta t2-t1: " 
              << std::chrono::duration_cast<std::chrono::milliseconds>(t2 - t1).count()
              << " milliseconds" << std::endl;
}

Output:

Delta t2-t1: 3 milliseconds

Link to demo: http://cpp.sh/2zdtu

UNIX nonblocking I/O: O_NONBLOCK vs. FIONBIO

Prior to standardization there was ioctl(...FIONBIO...) and fcntl(...O_NDELAY...), but these behaved inconsistently between systems, and even within the same system. For example, it was common for FIONBIO to work on sockets and O_NDELAY to work on ttys, with a lot of inconsistency for things like pipes, fifos, and devices. And if you didn't know what kind of file descriptor you had, you'd have to set both to be sure. But in addition, a non-blocking read with no data available was also indicated inconsistently; depending on the OS and the type of file descriptor the read may return 0, or -1 with errno EAGAIN, or -1 with errno EWOULDBLOCK. Even today, setting FIONBIO or O_NDELAY on Solaris causes a read with no data to return 0 on a tty or pipe, or -1 with errno EAGAIN on a socket. However 0 is ambiguous since it is also returned for EOF.

POSIX addressed this with the introduction of O_NONBLOCK, which has standardized behavior across different systems and file descriptor types. Because existing systems usually want to avoid any changes to behavior which might break backward compatibility, POSIX defined a new flag rather than mandating specific behavior for one of the others. Some systems like Linux treat all 3 the same, and also define EAGAIN and EWOULDBLOCK to the same value, but systems wishing to maintain some other legacy behavior for backward compatibility can do so when the older mechanisms are used.

New programs should use fcntl(...O_NONBLOCK...), as standardized by POSIX.

What's the advantage of a Java enum versus a class with public static final fields?

The primary advantage is type safety. With a set of constants, any value of the same intrinsic type could be used, introducing errors. With an enum only the applicable values can be used.

For example

public static final int SIZE_SMALL  = 1;
public static final int SIZE_MEDIUM = 2;
public static final int SIZE_LARGE  = 3;

public void setSize(int newSize) { ... }

obj.setSize(15); // Compiles but likely to fail later

public enum Size { SMALL, MEDIUM, LARGE };

public void setSize(Size s) { ... }

obj.setSize( ? ); // Can't even express the above example with an enum

How to force Chrome's script debugger to reload javascript?

If you are making local changes to a javascript in the Developer Tools, you need to make sure that you turn OFF those changes before reloading the page.

In the Sources tab, with your script open, right-click in your script and click the "Local Modifications" option from the context menu. That brings up the list of scripts you've saved modifications to. If you see it in that window, Developer Tools will always keep your local copy rather than refreshing it from the server. Click the "revert" button, then refresh again, and you should get the fresh copy.

iterating quickly through list of tuples

The question is dead but still knowing one more way doesn't hurt:

my_list = [ (old1, new1), (old2, new2), (old3, new3), ... (oldN, newN)]

for first,*args in my_list:
    if first == Value:
        PAIR_FOUND = True
        MATCHING_VALUE = args
        break

Setting a spinner onClickListener() in Android

I suggest that all events for Spinner are divided on two types:

User events (you meant as "click" event).
Program events.

I also suggest that when you want to catch user event you just want to get rid off "program events". So it's pretty simple:

private void setSelectionWithoutDispatch(Spinner spinner, int position) {
    AdapterView.OnItemSelectedListener onItemSelectedListener = spinner.getOnItemSelectedListener();
    spinner.setOnItemSelectedListener(null);
    spinner.setSelection(position, false);
    spinner.setOnItemSelectedListener(onItemSelectedListener);
}

There's a key moment: you need setSelection(position, false). "false" in animation parameter will fire event immediately. The default behaviour is to push event to event queue.

How to find a value in an array and remove it by using PHP array functions?

To search an element in an array, you can use array_search function and to remove an element from an array you can use unset function. Ex:

<?php
$hackers = array ('Alan Kay', 'Peter Norvig', 'Linus Trovalds', 'Larry Page');

print_r($hackers);

// Search
$pos = array_search('Linus Trovalds', $hackers);

echo 'Linus Trovalds found at: ' . $pos;

// Remove from array
unset($hackers[$pos]);

print_r($hackers);

You can refer: https://www.php.net/manual/en/ref.array.php for more array related functions.

Public free web services for testing soap client

There is a bunch on here:

http://www.webservicex.net/WS/wscatlist.aspx

Just google for "Free WebService" or "Open WebService" and you'll find tons of open SOAP endpoints.

Remember, you can get a WSDL from any ASMX endpoint by adding ?WSDL to the url.

Is there any use for unique_ptr with array?

I have used unique_ptr<char[]> to implement a preallocated memory pools used in a game engine. The idea is to provide preallocated memory pools used instead of dynamic allocations for returning collision requests results and other stuff like particle physics without having to allocate / free memory at each frame. It's pretty convenient for this kind of scenarios where you need memory pools to allocate objects with limited life time (typically one, 2 or 3 frames) that do not require destruction logic (only memory deallocation).

Is a slash ("/") equivalent to an encoded slash ("%2F") in the path portion of an HTTP URL

From the data you gathered, I would tend to say that encoded "/" in an uri are meant to be seen as "/" again at application/cgi level.

That's to say, that if you're using apache with mod_rewrite for instance, it will not match pattern expecting slashes against URI with encoded slashes in it. However, once the appropriate module/cgi/... is called to handle the request, it's up to it to do the decoding and, for instance, retrieve a parameter including slashes as the first component of the URI.

If your application is then using this data to retrieve a file (whose filename contains a slash), that's probably a bad thing.

To sum up, I find it perfectly normal to see a difference of behaviour in "/" or "%2F" as their interpretation will be done at different levels.

Proper way to initialize a C# dictionary with values?

Object initializers were introduced in C# 3.0, check which framework version you are targeting.

Overview of C# 3.0

Styling a input type=number

I've been struggling with this on mobile and tablet. My solution was to use absolute positioning on the spinners, so I'm just posting it in case it helps anyone else:

_x000D_

<html><head>_x000D_
    <style>_x000D_
      body {padding: 10px;margin: 10px}_x000D_
      input[type=number] {_x000D_
        /*for absolutely positioning spinners*/_x000D_
        position: relative; _x000D_
        padding: 5px;_x000D_
        padding-right: 25px;_x000D_
      }_x000D_
_x000D_
      input[type=number]::-webkit-inner-spin-button,_x000D_
      input[type=number]::-webkit-outer-spin-button {_x000D_
        opacity: 1;_x000D_
      }_x000D_
_x000D_
      input[type=number]::-webkit-outer-spin-button, _x000D_
      input[type=number]::-webkit-inner-spin-button {_x000D_
        -webkit-appearance: inner-spin-button !important;_x000D_
        width: 25px;_x000D_
        position: absolute;_x000D_
        top: 0;_x000D_
        right: 0;_x000D_
        height: 100%;_x000D_
      }_x000D_
    </style>_x000D_
  <meta name="apple-mobile-web-app-capable" content="yes"/>_x000D_
  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1, user-scalable=0"/>_x000D_
  </head>_x000D_
  <body >_x000D_
    <input type="number" value="1" step="1" />_x000D_
_x000D_
  </body></html>

_x000D_

Box shadow in IE7 and IE8

You could try this

box-shadow:
progid:DXImageTransform.Microsoft.dropshadow(OffX=0, OffY=10, Color='#19000000'), 
progid:DXImageTransform.Microsoft.dropshadow(OffX=10, OffY=20, Color='#19000000'), 
progid:DXImageTransform.Microsoft.dropshadow(OffX=20, OffY=30, Color='#19000000'), 
progid:DXImageTransform.Microsoft.dropshadow(OffX=30, OffY=40, Color='#19000000');

Parsing date string in Go

If you have worked with time/date formatting/parsing in other languages you might have noticed that the other languages use special placeholders for time/date formatting. For eg ruby language uses

%d for day
%Y for year

etc. Golang, instead of using codes such as above, uses date and time format placeholders that look like date and time only. Go uses standard time, which is:

Mon Jan 2 15:04:05 MST 2006  (MST is GMT-0700)
or 
01/02 03:04:05PM '06 -0700

So if you notice Go uses

01 for the day of the month,
02 for the month
03 for hours,
04 for minutes
05 for second
and so on

Therefore for example for parsing 2020-01-29, layout string should be 06-01-02 or 2006-01-02.

You can refer to the full placeholder layout table at this link - https://golangbyexample.com/parse-time-in-golang/

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

You could use Linq's FirstOrDefault extension method:

string element = myList.FirstOrDefault(s => s.Contains(myString));

This will return the fist element that contains the substring myString, or null if no such element is found.

If all you need is the index, use the List<T> class's FindIndex method:

int index = myList.FindIndex(s => s.Contains(myString));

This will return the the index of fist element that contains the substring myString, or -1 if no such element is found.

How to set a radio button in Android

If you want to do it in code, you can call the check member of RadioGroup:

radioGroup.check(R.id.radioButtonId);

This will check the button you specify and uncheck the others.

How can I catch all the exceptions that will be thrown through reading and writing a file?

While I agree it's not good style to catch a raw Exception, there are ways of handling exceptions which provide for superior logging, and the ability to handle the unexpected. Since you are in an exceptional state, you are probably more interested in getting good information than in response time, so instanceof performance shouldn't be a big hit.

try{
    // IO code
} catch (Exception e){
    if(e instanceof IOException){
        // handle this exception type
    } else if (e instanceof AnotherExceptionType){
        //handle this one
    } else {
        // We didn't expect this one. What could it be? Let's log it, and let it bubble up the hierarchy.
        throw e;
    }
}

However, this doesn't take into consideration the fact that IO can also throw Errors. Errors are not Exceptions. Errors are a under a different inheritance hierarchy than Exceptions, though both share the base class Throwable. Since IO can throw Errors, you may want to go so far as to catch Throwable

try{
    // IO code
} catch (Throwable t){
    if(t instanceof Exception){
        if(t instanceof IOException){
            // handle this exception type
        } else if (t instanceof AnotherExceptionType){
            //handle this one
        } else {
            // We didn't expect this Exception. What could it be? Let's log it, and let it bubble up the hierarchy.
        }
    } else if (t instanceof Error){
        if(t instanceof IOError){
            // handle this Error
        } else if (t instanceof AnotherError){
            //handle different Error
        } else {
            // We didn't expect this Error. What could it be? Let's log it, and let it bubble up the hierarchy.
        }
    } else {
        // This should never be reached, unless you have subclassed Throwable for your own purposes.
        throw t;
    }
}

What is init.py for?

It used to be a required part of a package (old, pre-3.3 "regular package", not newer 3.3+ "namespace package").

Here's the documentation.

Python defines two types of packages, regular packages and namespace packages. Regular packages are traditional packages as they existed in Python 3.2 and earlier. A regular package is typically implemented as a directory containing an __init__.py file. When a regular package is imported, this __init__.py file is implicitly executed, and the objects it defines are bound to names in the package’s namespace. The __init__.py file can contain the same Python code that any other module can contain, and Python will add some additional attributes to the module when it is imported.

But just click the link, it contains an example, more information, and an explanation of namespace packages, the kind of packages without __init__.py.

Android Error [Attempt to invoke virtual method 'void android.app.ActionBar' on a null object reference]

If anybody wants to use android.app.ActionBar and android.app.Activity you should change the app theme in styles.xml, for example:

<style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar">

The problem is you could be using an AppCompat theme.

On the other hand, if you want to use android.support.v7.app.ActionBar and you extend your activity with AppCompatActivity then you must use an AppCompat theme to avoid this issue, for example:

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">

Hope this helps.

Cannot find a differ supporting object '[object Object]' of type 'object'. NgFor only supports binding to Iterables such as Arrays

My solution is create a Pipe for return the values array or propierties object

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
  name: 'valueArray',
})
export class ValueArrayPipe implements PipeTransform {

  // El parametro object representa, los valores de las propiedades o indice
  transform(objects : any = []) {
    return Object.values(objects);
  }
}

The template Implement

<button ion-item *ngFor="let element of element_list | valueArray" >
    {{ element.any_property }}
</button>

How to finish current activity in Android

What I was doing was starting a new activity and then closing the current activity. So, remember this simple rule:

finish()
startActivity<...>()

and not

startActivity<...>()
finish()

Get program path in VB.NET?

You can get path by this code

Dim CurDir as string = My.Application.Info.DirectoryPath

Hex transparency in colors

Short answer

You can see the full table of percentages to hex values and run the code in this playground in https://play.golang.org/p/l1JaPYFzDkI .

Short explanation in pseudocode

Percentage to hex values

decimal = percentage * 255 / 100 . ex : decimal = 50*255/100 = 127.5
convert decimal to hexadecimal value . ex: 127.5 in decimal = 7*16ˆ1 + 15 = 7F in hexadecimal

Hex values to percentage

convert the hexaxdecimal value to decimal. ex: D6 = 13*16ˆ1 + 6 = 214
percentage = (value in decimal ) * 100 / 255. ex : 214 *100/255 = 84%

More infos for the conversion decimal <=> hexadecimal

Long answer: how to calculate in your head

The problem can be solved generically by a cross multiplication.

We have a percentage (ranging from 0 to 100 ) and another number (ranging from 0 to 255) then converted to hexadecimal.

100 <==> 255 (FF in hexadecimal)
0 <==> 0 (00 in hexadecimal)

For 1%

1 * 255 / 100 = 2,5
2,5 in hexa is 2 if you round it down.

For 2%

2 * 255 / 100 = 5
5 in hexa is 5 .

The table in the best answer gives the percentage by step of 5%.

How to calculate the numbers between in your head ? Due to the 2.5 increment, add 2 to the first and 3 to the next

95% — F2 // start
96% — F4 // add 2 to F2
97% — F7 // add 3 . Or F2 + 5 = F7
98% — F9 // add 2
99% — FC // add 3. 9 + 3 = 12 in hexa : C
100% — FF // add 2

I prefer to teach how to find the solution rather than showing an answer table you don't know where the results come from.

Give a man a fish and you feed him for a day; teach a man to fish and you feed him for a lifetime

Nexus 7 (2013) and Win 7 64 - cannot install USB driver despite checking many forums and online resources

I also got this problem and found quite simple solution. I have Samsung adb driver installed on my system. I tried "Update driver" -> "Let me pick" -> "Already installed drivers" -> Samsung adb driver. That worked well.

Bootstrap Alert Auto Close

Tiggers automatically and manually when needed

$(function () {
    TriggerAlertClose();
});

function TriggerAlertClose() {
    window.setTimeout(function () {
        $(".alert").fadeTo(1000, 0).slideUp(1000, function () {
            $(this).remove();
        });
    }, 5000);
}

Find what 2 numbers add to something and multiply to something

That's basically a set of 2 simultaneous equations:

x*y = a
X+y = b

(using the mathematical convention of x and y for the variables to solve and a and b for arbitrary constants).

But the solution involves a quadratic equation (because of the x*y), so depending on the actual values of a and b, there may not be a solution, or there may be multiple solutions.

How to include jQuery in ASP.Net project?

You can include the script file directly in your page/master page, etc using:

 <script type="text/javascript" src="/scripts/jquery.min.js"></script>

Us use a Content Delivery network like Google or Microsoft:

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>

or:

<script src="http://ajax.microsoft.com/ajax/jquery/jquery-1.4.2.js" type="text/javascript"></script>

Removing time from a Date object?

You can remove the time part from java.util.Date by setting the hour, minute, second and millisecond values to zero.

import java.util.Calendar;
import java.util.Date;

public class DateUtil {

    public static Date removeTime(Date date) {
        Calendar cal = Calendar.getInstance();
        cal.setTime(date);
        cal.set(Calendar.HOUR_OF_DAY, 0);
        cal.set(Calendar.MINUTE, 0);
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MILLISECOND, 0);
        return cal.getTime();
    }

}

Setting a windows batch file variable to the day of the week

This works for me

FOR /F "tokens=3" %%a in ('robocopy ^|find "Started"') DO SET TODAY=%%a

Java Constructor Inheritance

You essentially do inherit the constuctors in the sense that you can simply call super if and when appropriate, it's just that it would be error prone for reasons others have mentioned if it happened by default. The compiler can't presume when it is appropriate and when it isn't.

The job of the compiler is to provide as much flexibility as possible while reducing complexity and risk of unintended side-effects.

moment.js - UTC gives wrong date

By default, MomentJS parses in local time. If only a date string (with no time) is provided, the time defaults to midnight.

In your code, you create a local date and then convert it to the UTC timezone (in fact, it makes the moment instance switch to UTC mode), so when it is formatted, it is shifted (depending on your local time) forward or backwards.

If the local timezone is UTC+N (N being a positive number), and you parse a date-only string, you will get the previous date.

Here are some examples to illustrate it (my local time offset is UTC+3 during DST):

>>> moment('07-18-2013', 'MM-DD-YYYY').utc().format("YYYY-MM-DD HH:mm")
"2013-07-17 21:00"
>>> moment('07-18-2013 12:00', 'MM-DD-YYYY HH:mm').utc().format("YYYY-MM-DD HH:mm")
"2013-07-18 09:00"
>>> Date()
"Thu Jul 25 2013 14:28:45 GMT+0300 (Jerusalem Daylight Time)"

If you want the date-time string interpreted as UTC, you should be explicit about it:

>>> moment(new Date('07-18-2013 UTC')).utc().format("YYYY-MM-DD HH:mm")
"2013-07-18 00:00"

or, as Matt Johnson mentions in his answer, you can (and probably should) parse it as a UTC date in the first place using moment.utc() and include the format string as a second argument to prevent ambiguity.

>>> moment.utc('07-18-2013', 'MM-DD-YYYY').format("YYYY-MM-DD HH:mm")
"2013-07-18 00:00"

To go the other way around and convert a UTC date to a local date, you can use the local() method, as follows:

>>> moment.utc('07-18-2013', 'MM-DD-YYYY').local().format("YYYY-MM-DD HH:mm")
"2013-07-18 03:00"

Guzzle 6: no more json() method for responses

$response is instance of PSR-7 ResponseInterface. For more details see https://www.php-fig.org/psr/psr-7/#3-interfaces

getBody() returns StreamInterface:

/**
 * Gets the body of the message.
 *
 * @return StreamInterface Returns the body as a stream.
 */
public function getBody();

StreamInterface implements __toString() which does

Reads all data from the stream into a string, from the beginning to end.

Therefore, to read body as string, you have to cast it to string:

$stringBody = (string) $response->getBody()

Gotchas

json_decode($response->getBody() is not the best solution as it magically casts stream into string for you. json_decode() requires string as 1st argument.
Don't use $response->getBody()->getContents() unless you know what you're doing. If you read documentation for getContents(), it says: Returns the remaining contents in a string. Therefore, calling getContents() reads the rest of the stream and calling it again returns nothing because stream is already at the end. You'd have to rewind the stream between those calls.

How can I send JSON response in symfony2 controller

Symfony 2.1 has a JsonResponse class.

return new JsonResponse(array('name' => $name));

The passed in array will be JSON encoded the status code will default to 200 and the content type will be set to application/json.

There is also a handy setCallback function for JSONP.

Is there a way to automatically generate getters and setters in Eclipse?

Use Project Lombok or better Kotlin for your Pojos.

(Also, to add Kotlin to your resume ;) )

This :

public class BaseVO {
    protected Long id;

    @Override
    public boolean equals(Object obj) {
        if (obj == null || id == null)
            return false;

        if (obj instanceof BaseVO)
            return ((BaseVO) obj).getId().equals(id);

        return false; 
    }

    @Override
    public int hashCode() {
        return id == null ? null : id.hashCode();
    }
    // getter setter here
}

public class Subclass extends BaseVO {
    protected String name;
    protected String category;
    // getter setter here
}

would become this :

open class BaseVO(var id: Long? = null) {

    override fun hashCode(): Int {
        if (id != null)
            return id.hashCode()

        return super.hashCode()
    }

    override fun equals(other: Any?): Boolean {
        if (id == null || other == null || other !is BaseVO)
            return false

        return id.hashCode() == other.id?.hashCode()
    }
}

@Suppress("unused")
class Subclass(
        var name: String? = null,
        var category: String? = null
) : BaseVO()

Or use Kotlin's "data" classes. You end up writing even fewer lines of code.

What's the maximum value for an int in PHP?

From the PHP manual:

The size of an integer is platform-dependent, although a maximum value of about two billion is the usual value (that's 32 bits signed). PHP does not support unsigned integers. Integer size can be determined using the constant PHP_INT_SIZE, and maximum value using the constant PHP_INT_MAX since PHP 4.4.0 and PHP 5.0.5.

64-bit platforms usually have a maximum value of about 9E18, except on Windows prior to PHP 7, where it was always 32 bit.

Invalid shorthand property initializer

In options object you have used "=" sign to assign value to port but we have to use ":" to assign values to properties in object when using object literal to create an object i.e."{}" ,these curly brackets. Even when you use function expression or create an object inside object you have to use ":" sign. for e.g.:

    var rishabh = {
        class:"final year",
        roll:123,
        percent: function(marks1, marks2, marks3){
                      total = marks1 + marks2 + marks3;
                      this.percentage = total/3 }
                    };

john.percent(85,89,95);
console.log(rishabh.percentage);

here we have to use commas "," after each property. but you can use another style to create and initialize an object.

var john = new Object():
john.father = "raja";  //1st way to assign using dot operator
john["mother"] = "rani";// 2nd way to assign using brackets and key must be string

Populating a data frame in R in a loop

this works too.

df = NULL
for (k in 1:10)
    {
       x = 1
       y = 2
       z = 3
       df = rbind(df, data.frame(x,y,z))
     }

output will look like this

df #enter

x y z #col names
1 2 3

Twitter Bootstrap Multilevel Dropdown Menu

Updated Answer

^{* Updated answer which support the v2.1.1** bootstrap version stylesheet.}

^{**But be careful because this solution has been removed from v3}

Just wanted to point out that this solution is not needed anymore as the latest bootstrap now supports multi-level dropdowns by default. You can still use it if you're on older versions but for those who updated to the latest (v2.1.1 at the time of writing) it is not needed anymore. Here is a fiddle with the updated default multi-level dropdown straight from the documentation:

http://jsfiddle.net/2Smgv/2858/

Original Answer

There have been some issues raised on submenu support over at github and they are usually closed by the bootstrap developers, such as this one, so i think it is left to the developers using the bootstrap to work something out. Here is a demo i put together showing you how you can hack together a working sub-menu.

Relevant code

CSS

.dropdown-menu .sub-menu {
    left: 100%;
    position: absolute;
    top: 0;
    visibility: hidden;
    margin-top: -1px;
}

.dropdown-menu li:hover .sub-menu {
    visibility: visible;
    display: block;
}

.navbar .sub-menu:before {
    border-bottom: 7px solid transparent;
    border-left: none;
    border-right: 7px solid rgba(0, 0, 0, 0.2);
    border-top: 7px solid transparent;
    left: -7px;
    top: 10px;
}
.navbar .sub-menu:after {
    border-top: 6px solid transparent;
    border-left: none;
    border-right: 6px solid #fff;
    border-bottom: 6px solid transparent;
    left: 10px;
    top: 11px;
    left: -6px;
}

Created my own .sub-menu class to apply to the 2-level drop down menus, this way we can position them next to our menu items. Also modified the arrow to display it on the left of the submenu group.

Demo

MSSQL Error 'The underlying provider failed on Open'

You should see innerException to see what the inner cause of throwing of error is.

In my case, the original error was:

Unable to open the physical file "D:\Projects2\xCU\xCU\App_Data\xCUData_log.ldf". Operating system error 5: "5(Access is denied.)". An attempt to attach an auto-named database for file D:\Projects2\xCU\xCU\App_Data\xCUData.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share.

which solved by giving full permission to current user for accessing related mdf and ldf files using files' properties.

setting min date in jquery datepicker

$(function () {
    $('#datepicker').datepicker({
        dateFormat: 'yy-mm-dd',
        showButtonPanel: true,
        changeMonth: true,
        changeYear: true,
yearRange: '1999:2012',
        showOn: "button",
        buttonImage: "images/calendar.gif",
        buttonImageOnly: true,
        minDate: new Date(1999, 10 - 1, 25),
        maxDate: '+30Y',
        inline: true
    });
});

Just added year range option. It should solve the problem

Best way to return a value from a python script

If you want your script to return values, just do return [1,2,3] from a function wrapping your code but then you'd have to import your script from another script to even have any use for that information:

Return values (from a wrapping-function)

(again, this would have to be run by a separate Python script and be imported in order to even do any good):

import ...
def main():
    # calculate stuff
    return [1,2,3]

Exit codes as indicators

(This is generally just good for when you want to indicate to a governor what went wrong or simply the number of bugs/rows counted or w/e. Normally 0 is a good exit and >=1 is a bad exit but you could inter-prate them in any way you want to get data out of it)

import sys
# calculate and stuff
sys.exit(100)

And exit with a specific exit code depending on what you want that to tell your governor. I used exit codes when running script by a scheduling and monitoring environment to indicate what has happened.

(os._exit(100) also works, and is a bit more forceful)

Stdout as your relay

If not you'd have to use stdout to communicate with the outside world (like you've described). But that's generally a bad idea unless it's a parser executing your script and can catch whatever it is you're reporting to.

import sys
# calculate stuff
sys.stdout.write('Bugs: 5|Other: 10\n')
sys.stdout.flush()
sys.exit(0)

Are you running your script in a controlled scheduling environment then exit codes are the best way to go.

Files as conveyors

There's also the option to simply write information to a file, and store the result there.

# calculate
with open('finish.txt', 'wb') as fh:
    fh.write(str(5)+'\n')

And pick up the value/result from there. You could even do it in a CSV format for others to read simplistically.

Sockets as conveyors

If none of the above work, you can also use network sockets locally *(unix sockets is a great way on nix systems). These are a bit more intricate and deserve their own post/answer. But editing to add it here as it's a good option to communicate between processes. Especially if they should run multiple tasks and return values.

How do I use MySQL through XAMPP?

<?php
if(!@mysql_connect('127.0.0.1', 'root', '*your default password*'))
{
    echo "mysql not connected ".mysql_error();
    exit;

}
echo 'great work';
?>

if no error then you will get greatwork as output.

Try it saved my life XD XD

Create a custom View by inflating a layout?

A bit old, but I thought sharing how I'd do it, based on chubbsondubs' answer: I use FrameLayout (see Documentation), since it is used to contain a single view, and inflate into it the view from the xml.

Code following:

public class MyView extends FrameLayout {
    public MyView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initView();
    }

    public MyView(Context context, AttributeSet attrs) {
        super(context, attrs);
        initView();
    }

    public MyView(Context context) {
        super(context);
        initView();
    }

    private void initView() {
        inflate(getContext(), R.layout.my_view_layout, this);
    }
}

Why is $$ returning the same id as the parent process?

If you were asking how to get the PID of a known command it would resemble something like this:

If you had issued the command below #The command issued was ***

dd if=/dev/diskx of=/dev/disky

Then you would use:

PIDs=$(ps | grep dd | grep if | cut -b 1-5)

What happens here is it pipes all needed unique characters to a field and that field can be echoed using

echo $PIDs

How does MySQL CASE work?

CASE is more like a switch statement. It has two syntaxes you can use. The first lets you use any compare statements you want:

CASE 
    WHEN user_role = 'Manager' then 4
    WHEN user_name = 'Tom' then 27
    WHEN columnA <> columnB then 99
    ELSE -1 --unknown
END

The second style is for when you are only examining one value, and is a little more succinct:

CASE user_role
    WHEN 'Manager' then 4
    WHEN 'Part Time' then 7
    ELSE -1 --unknown
END

Get contentEditable caret index position

//global savedrange variable to store text range in
var savedrange = null;

function getSelection()
{
    var savedRange;
    if(window.getSelection && window.getSelection().rangeCount > 0) //FF,Chrome,Opera,Safari,IE9+
    {
        savedRange = window.getSelection().getRangeAt(0).cloneRange();
    }
    else if(document.selection)//IE 8 and lower
    { 
        savedRange = document.selection.createRange();
    }
    return savedRange;
}

$('#contentbox').keyup(function() { 
    var currentRange = getSelection();
    if(window.getSelection)
    {
        //do stuff with standards based object
    }
    else if(document.selection)
    { 
        //do stuff with microsoft object (ie8 and lower)
    }
});

Note: the range object its self can be stored in a variable, and can be re-selected at any time unless the contents of the contenteditable div change.

Reference for IE 8 and lower: http://msdn.microsoft.com/en-us/library/ms535872(VS.85).aspx

Reference for standards (all other) browsers: https://developer.mozilla.org/en/DOM/range (its the mozilla docs, but code works in chrome, safari, opera and ie9 too)

Load vs. Stress testing

Load Testing: Load testing is meant to test the system by constantly and steadily increasing the load on the system till the time it reaches the threshold limit.

Example For example, to check the email functionality of an application, it could be flooded with 1000 users at a time. Now, 1000 users can fire the email transactions (read, send, delete, forward, reply) in many different ways. If we take one transaction per user per hour, then it would be 1000 transactions per hour. By simulating 10 transactions/user, we could load test the email server by occupying it with 10000 transactions/hour.

Stress Testing: Under stress testing, various activities to overload the existing resources with excess jobs are carried out in an attempt to break the system down.

Example: As an example, a word processor like Writer1.1.0 by OpenOffice.org is utilized in development of letters, presentations, spread sheets etc… Purpose of our stress testing is to load it with the excess of characters.

To do this, we will repeatedly paste a line of data, till it reaches its threshold limit of handling large volume of text. As soon as the character size reaches 65,535 characters, it would simply refuse to accept more data. The result of stress testing on Writer 1.1.0 produces the result that, it does not crash under the stress and that it handle the situation gracefully, which make sure that application is working correctly even under rigorous stress conditions.

Using Excel VBA to export data to MS Access table

@Ahmed

Below is code that specifies fields from a named range for insertion into MS Access. The nice thing about this code is that you can name your fields in Excel whatever the hell you want (If you use * then the fields have to match exactly between Excel and Access) as you can see I have named an Excel column "Haha" even though the Access column is called "dte".

Sub test()
    dbWb = Application.ActiveWorkbook.FullName
    dsh = "[" & Application.ActiveSheet.Name & "$]" & "Data2"  'Data2 is a named range


sdbpath = "C:\Users\myname\Desktop\Database2.mdb"
sCommand = "INSERT INTO [main] ([dte], [test1], [values], [values2]) SELECT [haha],[test1],[values],[values2] FROM [Excel 8.0;HDR=YES;DATABASE=" & dbWb & "]." & dsh

Dim dbCon As New ADODB.Connection
Dim dbCommand As New ADODB.Command

dbCon.Open "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" & sdbpath & "; Jet OLEDB:Database Password=;"
dbCommand.ActiveConnection = dbCon

dbCommand.CommandText = sCommand
dbCommand.Execute

dbCon.Close


End Sub

Row count with PDO

You can combine the best method into one line or function, and have the new query auto-generated for you:

function getRowCount($q){ 
    global $db;
    return $db->query(preg_replace('/SELECT [A-Za-z,]+ FROM /i','SELECT count(*) FROM ',$q))->fetchColumn();
}

$numRows = getRowCount($query);

Cannot install NodeJs: /usr/bin/env: node: No such file or directory

sudo PATH="$PATH:/usr/local/bin" npm install -g <package-name>

How to search for an element in a golang slice

With a simple for loop:

for _, v := range myconfig {
    if v.Key == "key1" {
        // Found!
    }
}

Note that since element type of the slice is a struct (not a pointer), this may be inefficient if the struct type is "big" as the loop will copy each visited element into the loop variable.

It would be faster to use a range loop just on the index, this avoids copying the elements:

for i := range myconfig {
    if myconfig[i].Key == "key1" {
        // Found!
    }
}

Notes:

It depends on your case whether multiple configs may exist with the same key, but if not, you should break out of the loop if a match is found (to avoid searching for others).

for i := range myconfig {
    if myconfig[i].Key == "key1" {
        // Found!
        break
    }
}

Also if this is a frequent operation, you should consider building a map from it which you can simply index, e.g.

// Build a config map:
confMap := map[string]string{}
for _, v := range myconfig {
    confMap[v.Key] = v.Value
}

// And then to find values by key:
if v, ok := confMap["key1"]; ok {
    // Found
}

Inline CSS styles in React: how to implement a:hover?

Checkout Typestyle if you are using React with Typescript.

Below is a sample code for :hover

import {style} from "typestyle";

/** convert a style object to a CSS class name */
const niceColors = style({
  transition: 'color .2s',
  color: 'blue',
  $nest: {
    '&:hover': {
      color: 'red'
    }
  }
});

<h1 className={niceColors}>Hello world</h1>

How to validate email id in angularJs using ng-pattern

I have tried wit the below regex it is working fine.

Email validation : \w+([-+.']\w+)@\w+([-.]\w+).\w+([-.]\w+)*

Get Row Index on Asp.net Rowcommand event

I was able to use @rahularyansharma's answer above in my own project, with one minor modification. I needed to get the value of particular cells on the row on which the user clicks a LinkButton. The second line can be modified to get the value of as many cells as you wish.

Here is my solution:

GridViewRow gvr = (GridViewRow)(((LinkButton)e.CommandSource).NamingContainer);
string typecore = gvr.Cells[3].Text.ToString().Trim();

JTable How to refresh table model after insert delete or update the data.

I did it like this in my Jtable its autorefreshing after 300 ms;

DefaultTableModel tableModel = new DefaultTableModel(){
public boolean isCellEditable(int nRow, int nCol) {
                return false;
            }
};
JTable table = new JTable();

Timer t = new Timer(300, new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                addColumns();
                remakeData(set);
                table.setModel(model);
            }
        });
        t.start();

private void addColumns() {
        model.setColumnCount(0);
        model.addColumn("NAME");
            model.addColumn("EMAIL");} 

 private void remakeData(CollectionType< Objects > name) {
    model.setRowCount(0);
    for (CollectionType Objects : name){
    String n = Object.getName();
    String e = Object.getEmail();
    model.insertRow(model.getRowCount(),new Object[] { n,e });
    }}

I doubt it will do good with large number of objects like over 500, only other way is to implement TableModelListener in your class, but i did not understand how to use it well. look at http://download.oracle.com/javase/tutorial/uiswing/components/table.html#modelchange

Converting an integer to binary in C

You can convert decimal to bin, hexa to decimal, hexa to bin, vice-versa etc by following this example. CONVERTING DECIMAL TO BIN

int convert_to_bin(int number){
    int binary = 0, counter = 0;
    while(number > 0){
        int remainder = number % 2;
        number /= 2;
        binary += pow(10, counter) * remainder;
        counter++;
    }   
}

Then you can print binary equivalent like this:

printf("08%d", convert_to_bin(13)); //shows leading zeros

How to start up spring-boot application via command line?

To run the spring-boot application, need to follow some step.

Maven setup (ignore if already setup):

a. Install maven from https://maven.apache.org/download.cgi

b. Unzip maven and keep in C drive (you can keep any location. Path location will be changed accordingly).

c. Set MAVEN_HOME in system variable.

d. Set path for maven

Add Maven Plugin to POM.XML

<build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build>

Build Spring Boot Project with Maven

   maven package

     mvn install / mvn clean install

Run Spring Boot app using Maven:
```
    mvn spring-boot:run
```

[optional] Run Spring Boot app with java -jar command

     java -jar target/mywebserviceapp-0.0.1-SNAPSHOT.jar

How to set a parameter in a HttpServletRequest?

The most upvoted solution generally works but for Spring and/or Spring Boot, the values will not wire to parameters in controller methods annotated with @RequestParam unless you specifically implemented getParameterValues(). I combined the solution(s) here and from this blog:

import java.util.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

public class MutableHttpRequest extends HttpServletRequestWrapper {

    private final Map<String, String[]> mutableParams = new HashMap<>();

    public MutableHttpRequest(final HttpServletRequest request) {
        super(request);
    }

    public MutableHttpRequest addParameter(String name, String value) {
        if (value != null)
            mutableParams.put(name, new String[] { value });

        return this;
    }

    @Override
    public String getParameter(final String name) {
        String[] values = getParameterMap().get(name);

        return Arrays.stream(values)
                .findFirst()
                .orElse(super.getParameter(name));
    }

    @Override
    public Map<String, String[]> getParameterMap() {
        Map<String, String[]> allParameters = new HashMap<>();
        allParameters.putAll(super.getParameterMap());
        allParameters.putAll(mutableParams);

        return Collections.unmodifiableMap(allParameters);
    }

    @Override
    public Enumeration<String> getParameterNames() {
        return Collections.enumeration(getParameterMap().keySet());
    }

    @Override
    public String[] getParameterValues(final String name) {
        return getParameterMap().get(name);
    }
}

note that this code is not super-optimized but it works.

What are the applications of binary trees?

To squabble about the performance of binary-trees is meaningless - they are not a data structure, but a family of data structures, all with different performance characteristics. While it is true that unbalanced binary trees perform much worse than self-balancing binary trees for searching, there are many binary trees (such as binary tries) for which "balancing" has no meaning.

Applications of binary trees

Binary Search Tree - Used in many search applications where data is constantly entering/leaving, such as the map and set objects in many languages' libraries.
Binary Space Partition - Used in almost every 3D video game to determine what objects need to be rendered.
Binary Tries - Used in almost every high-bandwidth router for storing router-tables.
Hash Trees - used in p2p programs and specialized image-signatures in which a hash needs to be verified, but the whole file is not available.
Heaps - Used in implementing efficient priority-queues, which in turn are used for scheduling processes in many operating systems, Quality-of-Service in routers, and A* (path-finding algorithm used in AI applications, including robotics and video games). Also used in heap-sort.
Huffman Coding Tree (Chip Uni) - used in compression algorithms, such as those used by the .jpeg and .mp3 file-formats.
GGM Trees - Used in cryptographic applications to generate a tree of pseudo-random numbers.
Syntax Tree - Constructed by compilers and (implicitly) calculators to parse expressions.
Treap - Randomized data structure used in wireless networking and memory allocation.
T-tree - Though most databases use some form of B-tree to store data on the drive, databases which keep all (most) their data in memory often use T-trees to do so.

The reason that binary trees are used more often than n-ary trees for searching is that n-ary trees are more complex, but usually provide no real speed advantage.

In a (balanced) binary tree with m nodes, moving from one level to the next requires one comparison, and there are log_2(m) levels, for a total of log_2(m) comparisons.

In contrast, an n-ary tree will require log_2(n) comparisons (using a binary search) to move to the next level. Since there are log_n(m) total levels, the search will require log_2(n)*log_n(m) = log_2(m) comparisons total. So, though n-ary trees are more complex, they provide no advantage in terms of total comparisons necessary.

(However, n-ary trees are still useful in niche-situations. The examples that come immediately to mind are quad-trees and other space-partitioning trees, where divisioning space using only two nodes per level would make the logic unnecessarily complex; and B-trees used in many databases, where the limiting factor is not how many comparisons are done at each level but how many nodes can be loaded from the hard-drive at once)

Adjust width and height of iframe to fit with content in it

In case someone getting to here: I had a problem with the solutions when I removed divs from the iframe - the iframe didnt got shorter.

There is an Jquery plugin that does the job:

http://www.jqueryscript.net/layout/jQuery-Plugin-For-Auto-Resizing-iFrame-iFrame-Resizer.html

Java: Most efficient method to iterate over all elements in a org.w3c.dom.Document?

I also stumbled over this problem recently. Here is my solution. I wanted to avoid recursion, so I used a while loop.

Because of the adds and removes in arbitrary places on the list, I went with the LinkedList implementation.

/* traverses tree starting with given node */
  private static List<Node> traverse(Node n)
  {
    return traverse(Arrays.asList(n));
  }

  /* traverses tree starting with given nodes */
  private static List<Node> traverse(List<Node> nodes)
  {
    List<Node> open = new LinkedList<Node>(nodes);
    List<Node> visited = new LinkedList<Node>();

    ListIterator<Node> it = open.listIterator();
    while (it.hasNext() || it.hasPrevious())
    {
      Node unvisited;
      if (it.hasNext())
        unvisited = it.next();
      else
        unvisited = it.previous();

      it.remove();

      List<Node> children = getChildren(unvisited);
      for (Node child : children)
        it.add(child);

      visited.add(unvisited);
    }

    return visited;
  }

  private static List<Node> getChildren(Node n)
  {
    List<Node> children = asList(n.getChildNodes());
    Iterator<Node> it = children.iterator();
    while (it.hasNext())
      if (it.next().getNodeType() != Node.ELEMENT_NODE)
        it.remove();
    return children;
  }

  private static List<Node> asList(NodeList nodes)
  {
    List<Node> list = new ArrayList<Node>(nodes.getLength());
    for (int i = 0, l = nodes.getLength(); i < l; i++)
      list.add(nodes.item(i));
    return list;
  }

Add button to navigationbar programmatically

How to add an add button to the navbar in swift:

self.navigationItem.rightBarButtonItem = UIBarButtonItem(barButtonSystemItem: .Add, target: self, action: "onAdd:")

onAdd:

func onAdd(sender: AnyObject) {
}

How to convert date to timestamp?

It should have been in this standard date format YYYY-MM-DD, to use below equation. You may have time along with example: 2020-04-24 16:51:56 or 2020-04-24T16:51:56+05:30. It will work fine but date format should like this YYYY-MM-DD only.

var myDate = "2020-04-24";
var timestamp = +new Date(myDate)

Java, How to specify absolute value and square roots

Math.sqrt(Math.abs(variable))

Couldn't be more simple can it ?

What is the correct XPath for choosing attributes that contain "foo"?

John C is the closest, but XPath is case sensitive, so the correct XPath would be:

/bla/a[contains(@prop, 'Foo')]

How can I close a window with Javascript on Mozilla Firefox 3?

This code works for both IE 7 and the latest version of Mozilla although the default setting in mozilla doesnt allow to close a window through javascript.

Here is the code:

function F11() { window.open('','_parent',''); window.open("login.aspx", "", "channelmode"); window.close(); }

To change the default setting :

1.type"about:config " in your firefox address bar and enter;

2.make sure your "dom.allow_scripts_to_close_windows" is true

How to set response header in JAX-RS so that user sees download popup for Excel?

You don't need HttpServletResponse to set a header on the response. You can do it using javax.ws.rs.core.Response. Just make your method to return Response instead of entity:

return Response.ok(entity).header("Content-Disposition", "attachment; filename=\"" + fileName + "\"").build()

If you still want to use HttpServletResponse you can get it either injected to one of the class fields, or using property, or to method parameter:

@Path("/resource")
class MyResource {

  // one way to get HttpServletResponse
  @Context
  private HttpServletResponse anotherServletResponse;

  // another way
  Response myMethod(@Context HttpServletResponse servletResponse) {
      // ... code
  }
}

Error: unmappable character for encoding UTF8 during maven compilation

When i inspect the console i found that the version of maven compiler is 2.5.1 but in other side i try to build my project with maven 3.2.2.So after writting the exact version in pom.xml, it works good. Here is the full tag:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-compiler-plugin</artifactId>
  <version>3.2</version>
  <configuration>
   ....
  <configuration>
</plugin>

jQuery .each() with input elements

$.each($('input[type=number]'),function(){
  alert($(this).val());
});

This will alert the value of input type number fields

Demo is present at http://jsfiddle.net/2dJAN/33/

What is a regex to match ONLY an empty string?

Try looking here: https://docs.python.org/2/library/re.html

I ran into the same problem you had though. I could only build a regex that would match only the empty string and also "\n". Try trimming/replacing the newline characters in the string with another character first.

I was using http://pythex.org/ and trying weird regexes like these:

()

(?:)

^$

^(?:^\n){0}$

and so on.

Why should hash functions use a prime number modulus?

Just to provide an alternate viewpoint there's this site:

http://www.codexon.com/posts/hash-functions-the-modulo-prime-myth

Which contends that you should use the largest number of buckets possible as opposed to to rounding down to a prime number of buckets. It seems like a reasonable possibility. Intuitively, I can certainly see how a larger number of buckets would be better, but I'm unable to make a mathematical argument of this.

To check if string contains particular word

Maybe this post is old, but I came across it and used the "wrong" usage. The best way to find a keyword is using .contains, example:

if ( d.contains("hello")) {
            System.out.println("I found the keyword");
}

How do I 'svn add' all unversioned files to SVN?

svn add --force .

This will add any unversioned file in the current directory and all versioned child directories.

How do I collapse sections of code in Visual Studio Code for Windows?

This feature is now supported, since Visual Studio Code 1.17. To fold/collapse your code block, just add the region tags, such as //#region my block name and //#endregion if coding in TypeScript/JavaScript.

Example:

Region Folding

Avoid browser popup blockers

Based on Jason Sebring's very useful tip, and on the stuff covered here and there, I found a perfect solution for my case:

Pseudo code with Javascript snippets:

immediately create a blank popup on user action
```
 var importantStuff = window.open('', '_blank');
```
(Enrich the call to window.open with whatever additional options you need.)

Optional: add some "waiting" info message. Examples:

a) An external HTML page: replace the above line with
```
 var importantStuff = window.open('http://example.com/waiting.html', '_blank');
```
b) Text: add the following line below the above one:
```
 importantStuff.document.write('Loading preview...');
```
fill it with content when ready (when the AJAX call is returned, for instance)
```
 importantStuff.location.href = 'https://example.com/finally.html';
```
Alternatively, you could close the window here if you don't need it after all (if ajax request fails, for example - thanks to @Goose for the comment):
```
 importantStuff.close();
```

I actually use this solution for a mailto redirection, and it works on all my browsers (windows 7, Android). The _blank bit helps for the mailto redirection to work on mobile, btw.

How can I prevent the textarea from stretching beyond his parent DIV element? (google-chrome issue only)

I'm hoping you are having the same problem that I had... my issue was simple: Make a fixed textarea with locked percentages inside the container (I'm new to CSS/JS/HTML, so bear with me, if I don't get the lingo correct) so that no matter the device it's displaying on, the box filling the container (the table cell) takes up the correct amount of space. Here's how I solved it:

<table width=100%>
    <tr class="idbbs">
        B.S.:
    </tr></br>
    <tr>
        <textarea id="bsinpt"></textarea>
    </tr>
</table>

Then CSS Looks like this...

#bsinpt
{
    color: gainsboro;
    float: none;
    background: black;
    text-align: left;
    font-family: "Helvetica", "Tahoma", "Verdana", "Arial Black", sans-serif;
    font-size: 100%;
  position: absolute;
  min-height: 60%;
  min-width: 88%;
  max-height: 60%;
  max-width: 88%;
  resize: none;
    border-top-color: lightsteelblue;
    border-top-width: 1px;
    border-left-color: lightsteelblue;
    border-left-width: 1px;
    border-right-color: lightsteelblue;
    border-right-width: 1px;
    border-bottom-color: lightsteelblue;
    border-bottom-width: 1px;
}

Sorry for the sloppy code block here, but I had to show you what's important and I don't know how to insert quoted CSS code on this website. In any case, to ensure you see what I'm talking about, the important CSS is less indented here...

What I then did (as shown here) is very specifically tweak the percentages until I found the ones that worked perfectly to fit display, no matter what device screen is used.

Granted, I think the "resize: none;" is overkill, but better safe than sorry and now the consumers will not have anyway to resize the box, nor will it matter what device they are viewing it from.

It works great.

Get everything after the dash in a string in JavaScript

I came to this question because I needed what OP was asking but more than what other answers offered (they're technically correct, but too minimal for my purposes). I've made my own solution; maybe it'll help someone else.

Let's say your string is 'Version 12.34.56'. If you use '.' to split, the other answers will tend to give you '56', when maybe what you actually want is '.34.56' (i.e. everything from the first occurrence instead of the last, but OP's specific case just so happened to only have one occurrence). Perhaps you might even want 'Version 12'.

I've also written this to handle certain failures (like if null gets passed or an empty string, etc.). In those cases, the following function will return false.

Use

splitAtSearch('Version 12.34.56', '.') // Returns ['Version 12', '.34.56']

Function

/**
 * Splits string based on first result in search
 * @param {string} string - String to split
 * @param {string} search - Characters to split at
 * @return {array|false} - Strings, split at search
 *                        False on blank string or invalid type
 */
function splitAtSearch( string, search ) {
    let isValid = string !== ''              // Disallow Empty
               && typeof string === 'string' // Allow strings
               || typeof string === 'number' // Allow numbers

    if (!isValid) { return false } // Failed
    else          { string += '' } // Ensure string type

    // Search
    let searchIndex = string.indexOf(search)
    let isBlank     = (''+search) === ''
    let isFound     = searchIndex !== -1
    let noSplit     = searchIndex === 0
    let parts       = []

    // Remains whole
    if (!isFound || noSplit || isBlank) {
        parts[0] = string
    }
    // Requires splitting
    else {
        parts[0] = string.substring(0, searchIndex)
        parts[1] = string.substring(searchIndex)
    }

    return parts
}

Examples

splitAtSearch('')                      // false
splitAtSearch(true)                    // false
splitAtSearch(false)                   // false
splitAtSearch(null)                    // false
splitAtSearch(undefined)               // false
splitAtSearch(NaN)                     // ['NaN']
splitAtSearch('foobar', 'ba')          // ['foo', 'bar']
splitAtSearch('foobar', '')            // ['foobar']
splitAtSearch('foobar', 'z')           // ['foobar']
splitAtSearch('foobar', 'foo')         // ['foobar'] not ['', 'foobar']
splitAtSearch('blah bleh bluh', 'bl')  // ['blah bleh bluh']
splitAtSearch('blah bleh bluh', 'ble') // ['blah ', 'bleh bluh']
splitAtSearch('$10.99', '.')           // ['$10', '.99']
splitAtSearch(3.14159, '.')            // ['3', '.14159']

Node Express sending image files as API response

There is an api in Express.

res.sendFile

app.get('/report/:chart_id/:user_id', function (req, res) {
    // res.sendFile(filepath);
});

http://expressjs.com/en/api.html#res.sendFile

Most efficient solution for reading CLOB to String, and String to CLOB in Java?

private String convertToString(java.sql.Clob data)
{
    final StringBuilder builder= new StringBuilder();

    try
    {
        final Reader         reader = data.getCharacterStream();
        final BufferedReader br     = new BufferedReader(reader);

        int b;
        while(-1 != (b = br.read()))
        {
            builder.append((char)b);
        }

        br.close();
    }
    catch (SQLException e)
    {
        log.error("Within SQLException, Could not convert CLOB to string",e);
        return e.toString();
    }
    catch (IOException e)
    {
        log.error("Within IOException, Could not convert CLOB to string",e);
        return e.toString();
    }
    //enter code here
    return builder.toString();
}

How to get Map data using JDBCTemplate.queryForMap

I know this is really old, but this is the simplest way to query for Map.

Simply implement the ResultSetExtractor interface to define what type you want to return. Below is an example of how to use this. You'll be mapping it manually, but for a simple map, it should be straightforward.

jdbcTemplate.query("select string1,string2 from table where x=1", new ResultSetExtractor<Map>(){
    @Override
    public Map extractData(ResultSet rs) throws SQLException,DataAccessException {
        HashMap<String,String> mapRet= new HashMap<String,String>();
        while(rs.next()){
            mapRet.put(rs.getString("string1"),rs.getString("string2"));
        }
        return mapRet;
    }
});

This will give you a return type of Map that has multiple rows (however many your query returned) and not a list of Maps. You can view the ResultSetExtractor docs here: http://docs.spring.io/spring-framework/docs/2.5.6/api/org/springframework/jdbc/core/ResultSetExtractor.html

Android: How to change CheckBox size?

I could not find the relevant answer for my requirement which I figured it out. So, this answer is for checkbox with text like below where you want to resize the checkbox drawable and text separately.

You need two PNGs cb_checked.png and cb_unchechecked.png add them to drawable folder

Now create cb_bg_checked.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:tools="http://schemas.android.com/tools"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/cb_checked"
        android:height="22dp" <!-- This is the size of your checkbox -->
        android:width="22dp"  <!-- This is the size of your checkbox -->
        android:right="6dp"   <!-- This is the padding between cb and text -->
        tools:targetApi="m"
        tools:ignore="UnusedAttribute" />
</layer-list>

And, cb_bg_unchecked.xml

 <?xml version="1.0" encoding="utf-8"?>
    <layer-list xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools">
        <item android:drawable="@drawable/cb_unchechecked"
            android:height="22dp" <!-- This is the size of your checkbox -->
            android:width="22dp"  <!-- This is the size of your checkbox -->
            android:right="6dp"   <!-- This is the padding between cb and text -->
            tools:targetApi="m"
            tools:ignore="UnusedAttribute" />
    </layer-list>

Then create a selector XML checkbox.xml

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/cb_bg_checked" android:state_checked="true"/>
    <item android:drawable="@drawable/cb_bg_unchecked" android:state_checked="false"/>
</selector>

Now define it your layout.xml like this

<CheckBox
  android:id="@+id/checkbox_with_text"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:checked="true"
  android:button="@drawable/checkbox"
  android:text="This is text"
  android:textColor="@color/white"
  android:textSize="14dp" /> <!-- Here you can resize text -->

How to make a checkbox checked with jQuery?

$('#test').prop('checked', true);

Note only in jQuery 1.6+

Tomcat manager/html is not available?

I had the situatuion when tomcat manager did not start. I had this exception in my logs/manager.DDD-MM-YY.log:

org.apache.catalina.core.StandardContext filterStart
SEVERE: Exception starting filter CSRF
java.lang.ClassNotFoundException: org.apache.catalina.filters.CsrfPreventionFilter
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        ...

This exception was raised because I used a version of tomcat that hadn't CSRF prevention filter. Tomcat 6.0.24 doesn't have the CSRF prevention filter in it. The first version that has it is the 6.0.30 version (at least. according to the changelog). As a result, Tomcat Manager was uncompatible with version of Tomcat that I used. I've digged description of this issue here: http://blog.techstacks.com/.m/2009/05/tomcat-management-setting-up-tomcat/comments/

Steps to fix it:

Check version of tomcat installed by running "sh version.sh" from your tomcat/bin directory
Download corresponding version of tomcat
Stop tomcat
Remove your webapps/manager directory and copy manager application from distributive that you've downloaded.
Start tomcat

Now you should be able to access tomcat manager.

Showing an image from an array of images - Javascript

This is a simple example and try to combine it with yours using some modifications. I prefer you set all the images in one array in order to make your code easier to read and shorter:

var myImage = document.getElementById("mainImage");

var imageArray = ["_images/image1.jpg","_images/image2.jpg","_images/image3.jpg",
  "_images/image4.jpg","_images/image5.jpg","_images/image6.jpg"];

var imageIndex = 0; 

function changeImage() {
  myImage.setAttribute("src",imageArray[imageIndex]);
  imageIndex = (imageIndex + 1) % imageArray.length;
}

setInterval(changeImage, 5000);

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.

PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL

The following simpler shell script worked for me.

#!/bin/bash
for i in  `psql -U $1  -qt -c  "select tablename from pg_tables where schemaname='$2'"`
do
psql -U $1 -c  "alter table $2.$i set schema $3"
done

Where input $1 - username (database) $2 = existing schema $3 = to new schema.

Fit background image to div

If what you need is the image to have the same dimensions of the div, I think this is the most elegant solution:

background-size: 100% 100%;

If not, the answer by @grc is the most appropriated one.

Source: http://www.w3schools.com/cssref/css3_pr_background-size.asp

What is the best way to return different types of ResponseEntity in Spring MVC or Spring-Boot

You can also implement like this to return Success and Error on a same request mapping method,use Object class(Parent class of every class in java) :-

public ResponseEntity< Object> method() {                                                                                                                                                                                                                                                                                                                                                                                  
    boolean b = //  logic  here   
      if (b)  
        return new ResponseEntity< Object>(HttpStatus.OK);      
    else      
        return new ResponseEntity< Object>(HttpStatus.CONFLICT); //appropriate error code   
}

Python return statement error " 'return' outside function"

As per the documentation on the return statement, return may only occur syntactically nested in a function definition. The same is true for yield.

Find the number of downloads for a particular app in apple appstore

I think developers can do this for their own apps via iTunes Connect but this doesn't help you if you are looking for stats on other peoples apps.

148Apps also have some aggregate AppStore metrics on their web site that could be useful to you but, again, doesn't really give a low-level breakdown of numbers.

You could also scrape some stats from the RSS feeds generated by the iTunes Store RSS Generator but, again, this just gets currently popular apps rather than actual download numbers.

How can I sort generic list DESC and ASC?

Very simple way to sort List with int values in Descending order:

li.Sort((a,b)=> b-a);

Hope that this helps!

Curl setting Content-Type incorrectly

I think you want to specify

-H "Content-Type:text/xml"

with a colon, not an equals.

Creating Threads in python

Python 3 has the facility of Launching parallel tasks. This makes our work easier.

It has for thread pooling and Process pooling.

The following gives an insight:

ThreadPoolExecutor Example

import concurrent.futures
import urllib.request

URLS = ['http://www.foxnews.com/',
        'http://www.cnn.com/',
        'http://europe.wsj.com/',
        'http://www.bbc.co.uk/',
        'http://some-made-up-domain.com/']

# Retrieve a single page and report the URL and contents
def load_url(url, timeout):
    with urllib.request.urlopen(url, timeout=timeout) as conn:
        return conn.read()

# We can use a with statement to ensure threads are cleaned up promptly
with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:
    # Start the load operations and mark each future with its URL
    future_to_url = {executor.submit(load_url, url, 60): url for url in URLS}
    for future in concurrent.futures.as_completed(future_to_url):
        url = future_to_url[future]
        try:
            data = future.result()
        except Exception as exc:
            print('%r generated an exception: %s' % (url, exc))
        else:
            print('%r page is %d bytes' % (url, len(data)))

Another Example

import concurrent.futures
import math

PRIMES = [
    112272535095293,
    112582705942171,
    112272535095293,
    115280095190773,
    115797848077099,
    1099726899285419]

def is_prime(n):
    if n % 2 == 0:
        return False

    sqrt_n = int(math.floor(math.sqrt(n)))
    for i in range(3, sqrt_n + 1, 2):
        if n % i == 0:
            return False
    return True

def main():
    with concurrent.futures.ThreadPoolExecutor(max_workers=5) as executor:
        for number, prime in zip(PRIMES, executor.map(is_prime, PRIMES)):
            print('%d is prime: %s' % (number, prime))

if __name__ == '__main__':
    main()

"This SqlTransaction has completed; it is no longer usable."... configuration error?

I believe this error message is due to a "zombie transaction".

Look for possible areas where the transacton is being committed twice (or rolled back twice, or rolled back and committed, etc.). Does the .Net code commit the transaction after the SP has already committed it? Does the .Net code roll it back on encountering an error, then attempt to roll it back again in a catch (or finally) clause?

It's possible an error condition was never being hit on the old server, and thus the faulty "double rollback" code was never hit. Maybe now you have a situation where there is some configuration error on the new server, and now the faulty code is getting hit via exception handling.

Can you debug into the error code? Do you have a stack trace?

Do HTTP POST methods send data as a QueryString?

If your post try to reach the following URL

mypage.php?id=1

you will have the POST data but also GET data.

Github: Can I see the number of downloads for a repo?

11 years later...
Here's a small python3 snippet to retrieve the download count of the last 100 release assets:

import requests

owner = "twbs"
repo = "bootstrap"
h = {"Accept": "application/vnd.github.v3+json"}
u = f"https://api.github.com/repos/{owner}/{repo}/releases?per_page=100"
r = requests.get(u, headers=h).json()
r.reverse() # older tags first
for rel in r:
  if rel['assets']:
    tag = rel['tag_name']
    dls = rel['assets'][0]['download_count']
    pub = rel['published_at']
    print(f"Pub: {pub} | Tag: {tag} | Dls: {dls} ")

Pub: 2013-07-18T00:03:17Z | Tag: v1.2.0 | Dls: 1193 
Pub: 2013-08-19T21:20:59Z | Tag: v3.0.0 | Dls: 387786 
Pub: 2013-10-30T17:07:16Z | Tag: v3.0.1 | Dls: 102278 
Pub: 2013-11-06T21:58:55Z | Tag: v3.0.2 | Dls: 381136 
...
Pub: 2020-12-07T16:24:37Z | Tag: v5.0.0-beta1 | Dls: 93943

Demo

What use is find_package() if you need to specify CMAKE_MODULE_PATH anyway?

If you are running cmake to generate SomeLib yourself (say as part of a superbuild), consider using the User Package Registry. This requires no hard-coded paths and is cross-platform. On Windows (including mingw64) it works via the registry. If you examine how the list of installation prefixes is constructed by the CONFIG mode of the find_packages() command, you'll see that the User Package Registry is one of elements.

Brief how-to

Associate the targets of SomeLib that you need outside of that external project by adding them to an export set in the CMakeLists.txt files where they are created:

add_library(thingInSomeLib ...)
install(TARGETS thingInSomeLib Export SomeLib-export DESTINATION lib)

Create a XXXConfig.cmake file for SomeLib in its ${CMAKE_CURRENT_BUILD_DIR} and store this location in the User Package Registry by adding two calls to export() to the CMakeLists.txt associated with SomeLib:

export(EXPORT SomeLib-export NAMESPACE SomeLib:: FILE SomeLibConfig.cmake) # Create SomeLibConfig.cmake
export(PACKAGE SomeLib)                                                    # Store location of SomeLibConfig.cmake

Issue your find_package(SomeLib REQUIRED) commmand in the CMakeLists.txt file of the project that depends on SomeLib without the "non-cross-platform hard coded paths" tinkering with the CMAKE_MODULE_PATH.

When it might be the right approach

This approach is probably best suited for situations where you'll never use your software downstream of the build directory (e.g., you're cross-compiling and never install anything on your machine, or you're building the software just to run tests in the build directory), since it creates a link to a .cmake file in your "build" output, which may be temporary.

But if you're never actually installing SomeLib in your workflow, calling EXPORT(PACKAGE <name>) allows you to avoid the hard-coded path. And, of course, if you are installing SomeLib, you probably know your platform, CMAKE_MODULE_PATH, etc, so @user2288008's excellent answer will have you covered.

R: "Unary operator error" from multiline ggplot2 command

It looks like you might have inserted an extra + at the beginning of each line, which R is interpreting as a unary operator (like - interpreted as negation, rather than subtraction). I think what will work is

ggplot(combined.data, aes(x = region, y = expression, fill = species)) +
    geom_boxplot() +
    scale_fill_manual(values = c("yellow", "orange")) + 
    ggtitle("Expression comparisons for ACTB") + 
    theme(axis.text.x = element_text(angle=90, face="bold", colour="black"))

Perhaps you copy and pasted from the output of an R console? The console uses + at the start of the line when the input is incomplete.

Difference between web server, web container and application server

A Web application runs within a Web container of a Web server. The Web container provides the runtime environment through components that provide naming context and life cycle management. Some Web servers may also provide additional services such as security and concurrency control. A Web server may work with an EJB server to provide some of those services. A Web server, however, does not need to be located on the same machine as an EJB server.

Web applications are composed of web components and other data such as HTML pages. Web components can be servlets, JSP pages created with the JavaServer Pages™ technology, web filters, and web event listeners. These components typically execute in a web server and may respond to HTTP requests from web clients. Servlets, JSP pages, and filters may be used to generate HTML pages that are an application’s user interface. They may also be used to generate XML or other format data that is consumed by other application components.

Source: http://www.service-architecture.com/articles/application-servers/j2ee_web_server_or_container.html

Node.js fs.readdir recursive directory search

There is a new module called cup-readdir that recursively searches directories very fast. It uses asynchronous promises and outperforms many popular modules when dealing with deep directory structures.

It can return all files in an array and sort them by their properties, but lacks features like file filtering and entering symlinked directories. This could be useful for large projects where you simply want to get every file from a directory. Here is a link to their project homepage.

How do I get the value of a registry key and ONLY the value using powershell

Not sure at what version this capability arrived, but you can use something like this to return all the properties of multiple child registry entries in an array:

$InstalledSoftware = Get-ChildItem "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall" | ForEach-Object {Get-ItemProperty "Registry::$_"}

Only adding this as Google brought me here for a relevant reason and I eventually came up with the above one-liner for dredging the registry.

Best way to make a shell script daemon?

Some of the top-upvoted answers here are missing some important parts of what makes a daemon a daemon, as opposed to just a background process, or a background process detached from a shell.

This http://www.faqs.org/faqs/unix-faq/programmer/faq/ describes what is necessary to be a daemon. And this Run bash script as daemon implements the setsid, though it misses the chdir to root.

The original poster's question was actually more specific than "How do I create a daemon process using bash?", but since the subject and answers discuss daemonizing shell scripts generally, I think it's important to point it out (for interlopers like me looking into the fine details of creating a daemon).

Here's my rendition of a shell script that would behave according to the FAQ. Set DEBUG to true to see pretty output (but it also exits immediately rather than looping endlessly):

#!/bin/bash
DEBUG=false

# This part is for fun, if you consider shell scripts fun- and I do.
trap process_USR1 SIGUSR1

process_USR1() {
    echo 'Got signal USR1'
    echo 'Did you notice that the signal was acted upon only after the sleep was done'
    echo 'in the while loop? Interesting, yes? Yes.'
    exit 0
}
# End of fun. Now on to the business end of things.

print_debug() {
    whatiam="$1"; tty="$2"
    [[ "$tty" != "not a tty" ]] && {
        echo "" >$tty
        echo "$whatiam, PID $$" >$tty
        ps -o pid,sess,pgid -p $$ >$tty
        tty >$tty
    }
}

me_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
me_FILE=$(basename $0)
cd /

#### CHILD HERE --------------------------------------------------------------------->
if [ "$1" = "child" ] ; then   # 2. We are the child. We need to fork again.
    shift; tty="$1"; shift
    $DEBUG && print_debug "*** CHILD, NEW SESSION, NEW PGID" "$tty"
    umask 0
    $me_DIR/$me_FILE XXrefork_daemonXX "$tty" "$@" </dev/null >/dev/null 2>/dev/null &
    $DEBUG && [[ "$tty" != "not a tty" ]] && echo "CHILD OUT" >$tty
    exit 0
fi

##### ENTRY POINT HERE -------------------------------------------------------------->
if [ "$1" != "XXrefork_daemonXX" ] ; then # 1. This is where the original call starts.
    tty=$(tty)
    $DEBUG && print_debug "*** PARENT" "$tty"
    setsid $me_DIR/$me_FILE child "$tty" "$@" &
    $DEBUG && [[ "$tty" != "not a tty" ]] && echo "PARENT OUT" >$tty
    exit 0
fi

##### RUNS AFTER CHILD FORKS (actually, on Linux, clone()s. See strace -------------->
                               # 3. We have been reforked. Go to work.
exec >/tmp/outfile
exec 2>/tmp/errfile
exec 0</dev/null

shift; tty="$1"; shift

$DEBUG && print_debug "*** DAEMON" "$tty"
                               # The real stuff goes here. To exit, see fun (above)
$DEBUG && [[ "$tty" != "not a tty" ]]  && echo NOT A REAL DAEMON. NOT RUNNING WHILE LOOP. >$tty

$DEBUG || {
while true; do
    echo "Change this loop, so this silly no-op goes away." >/dev/null
    echo "Do something useful with your life, young padawan." >/dev/null
    sleep 10
done
}

$DEBUG && [[ "$tty" != "not a tty" ]] && sleep 3 && echo "DAEMON OUT" >$tty

exit # This may never run. Why is it here then? It's pretty.
     # Kind of like, "The End" at the end of a movie that you
     # already know is over. It's always nice.

Output looks like this when DEBUG is set to true. Notice how the session and process group ID (SESS, PGID) numbers change:

<shell_prompt>$ bash blahd

*** PARENT, PID 5180
  PID  SESS  PGID
 5180  1708  5180
/dev/pts/6
PARENT OUT
<shell_prompt>$ 
*** CHILD, NEW SESSION, NEW PGID, PID 5188
  PID  SESS  PGID
 5188  5188  5188
not a tty
CHILD OUT

*** DAEMON, PID 5198
  PID  SESS  PGID
 5198  5188  5188
not a tty
NOT A REAL DAEMON. NOT RUNNING WHILE LOOP.
DAEMON OUT

undefined reference to 'vtable for class' constructor

You're declaring a virtual function and not defining it:

virtual void calculateCredits();

Either define it or declare it as:

virtual void calculateCredits() = 0;

Or simply:

virtual void calculateCredits() { };

Read more about vftable: http://en.wikipedia.org/wiki/Virtual_method_table

ERROR: Sonar server 'http://localhost:9000' can not be reached

I got the same issue, and I changed to IP and it working well

Go to System References --> Network --> Advanced --> Open TCP/IP tabs --> copy the IPv4 Address.

change that IP instead localhost

Hope this can help

How can I make Visual Studio wrap lines at 80 characters?

You can also use

Ctrl+E, Ctrl+W

keyboard shortcut to toggle wrap lines on and off.

No module named 'openpyxl' - Python 3.4 - Ubuntu

If you're using Python3, then install:

python3 -m pip install --user xlsxwriter

This will run pip with the appropriate version of Python3. If you run bare pip3 and have many versions of Python install, it will still fail leading to more confusion.

The --user flag will allow to install as a regular user and no require root.

versionCode vs versionName in Android Manifest

I'm going to give you my interpretation of the only documentation I can find on the subject.

"for example to check an upgrade or downgrade relationship." <- You can downgrade an app.

"you should make sure that each successive release of your application uses a greater value. The system does not enforce this behavior" <- The number really should increase, but you can still downgrade an app.

android:versionCode — An integer value that represents the version of the application code, relative to other versions. The value is an integer so that other applications can programmatically evaluate it, for example to check an upgrade or downgrade relationship. You can set the value to any integer you want, however you should make sure that each successive release of your application uses a greater value. The system does not enforce this behavior, but increasing the value with successive releases is normative. Typically, you would release the first version of your application with versionCode set to 1, then monotonically increase the value with each release, regardless whether the release constitutes a major or minor release. This means that the android:versionCode value does not necessarily have a strong resemblance to the application release version that is visible to the user (see android:versionName, below). Applications and publishing services should not display this version value to users.

how to start the tomcat server in linux?

Go to the appropriate subdirectory of the EDQP Tomcat installation directory. The default directories are:

On Linux: /opt/server/tomcat/bin

On Windows: c:\server\tomcat\bin

Run the startup command:

On Linux: ./startup.sh

On Windows: % startup.bat

Run the shutdown command:

On Linux: ./shutdown.sh

On Windows: % shutdown.bat

Storing query results into a variable and modifying it inside a Stored Procedure

Try this example

CREATE PROCEDURE MyProc
BEGIN
    --Stored Procedure variables
    Declare @maxOr int; 
    Declare @maxCa int; 

    --Getting query result in the variable (first variant of syntax)
    SET @maxOr = (SELECT MAX(orId) FROM [order]); 

    --Another variant of seting variable from query
    SELECT @maxCa=MAX(caId) FROM [cart]; 

    --Updating record through the variable
    INSERT INTO [order_cart] (orId,caId)
    VALUES(@maxOr, @maxCa); 

    --return values to the program as dataset
    SELECT
       @maxOr AS maxOr,
       @maxCa AS maxCa

    -- return one int value as "return value"
    RETURN @maxOr
END
GO

SQL-command to call the stored procedure

EXEC MyProc

How to use an arraylist as a prepared statement parameter

why making life hard-

PreparedStatement pstmt = conn.prepareStatement("select * from employee where id in ("+ StringUtils.join(arraylistParameter.iterator(),",") +)");

Search of table names

If you want to look in all tables in all Databases server-wide and get output you can make use of the undocumented sp_MSforeachdb procedure:

sp_MSforeachdb 'SELECT "?" AS DB, * FROM [?].sys.tables WHERE name like ''%Table_Names%'''

Programs & Examples On #Entityset