org.hibernate.MappingException: Unknown entity

check that entity is defined in hibernate.cfg.xml or not.

Ant build failed: "Target "build..xml" does not exist"

I'm probably late but this worked for me:

Open your build.xml file located in your project's directory.
Copy and Paste the following code in the main project tag : <target name="build" />

Run multiple python scripts concurrently

I had to do this and used subprocess.

import subprocess

subprocess.run("python3 script1.py & python3 script2.py", shell=True)

ERROR 403 in loading resources like CSS and JS in my index.php

You need to change permissions on the folder bootstrap/css. Your super user may be able to access it but it doesn't mean apache or nginx have access to it, that's why you still need to change the permissions.

Tip: I usually make the apache/nginx's user group owner of that kind of folders and give 775 permission to it.

SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed

The issue is that ruby can not find a root certificate to trust. As of 1.9 ruby checks this. You will need to make sure that you have the curl certificate on your system in the form of a pem file. You will also need to make sure that the certificate is in the location that ruby expects it to be. You can get this certificate at...

http://curl.haxx.se/ca/cacert.pem

If your a RVM and OSX user then your certificate file location will vary based on what version of ruby your using. Setting the path explicitly with :ca_path is a BAD idea as your code will not be portable when it gets to production. There for you want to provide ruby with a certificate in the default location(and assume your dev ops guys know what they are doing). You can use dtruss to work out where the system is looking for the certificate file.

In my case the system was looking for the cert file in

/Users/stewart.matheson/.rvm/usr/ssl/cert.pem

however MACOSX system would expect a certificate in

/System/Library/OpenSSL/cert.pem

I copied the downloaded cert to this path and it worked. HTH

Box shadow for bottom side only

Try using online generator css3.me Change the value and get the code, pretty simple.

Writing html form data to a txt file without the use of a webserver

I know this is old, but it's the first example of saving form data to a txt file I found in a quick search. So I've made a couple edits to the above code that makes it work more smoothly. It's now easier to add more fields, including the radio button as @user6573234 requested.

https://jsfiddle.net/cgeiser/m0j7Lwyt/1/

<!DOCTYPE html>
<html>
<head>
<style>
form * {
  display: block;
  margin: 10px;
}
</style>
<script language="Javascript" >
function download() {
  var filename = window.document.myform.docname.value;
  var name =  window.document.myform.name.value;
  var text =  window.document.myform.text.value;
  var problem =  window.document.myform.problem.value;
  
  var pom = document.createElement('a');
  pom.setAttribute('href', 'data:text/plain;charset=utf-8,' + 
    "Your Name: " + encodeURIComponent(name) + "\n\n" +
    "Problem: " + encodeURIComponent(problem) + "\n\n" +
    encodeURIComponent(text)); 

  pom.setAttribute('download', filename);

  pom.style.display = 'none';
  document.body.appendChild(pom);

  pom.click();

  document.body.removeChild(pom);
}
</script>
</head>
<body>
<form name="myform" method="post" >
  <input type="text" id="docname" value="test.txt" />
  <input type="text" id="name" placeholder="Your Name" />
  <div style="display:unblock">
    Option 1 <input type="radio" value="Option 1" onclick="getElementById('problem').value=this.value; getElementById('problem').show()" style="display:inline" />
    Option 2 <input type="radio" value="Option 2" onclick="getElementById('problem').value=this.value;" style="display:inline" />
    <input type="text" id="problem" />
  </div>
  <textarea rows=3 cols=50 id="text" />Please type in this box. 
When you click the Download button, the contents of this box will be downloaded to your machine at the location you specify. Pretty nifty. </textarea>
  
  <input id="download_btn" type="submit" class="btn" style="width: 125px" onClick="download();" />
  
</form>
</body>
</html>

Make HTML5 video poster be same size as video itself

<video src="videofile.webm" poster="posterimage.jpg" controls preload="metadata">
    Sorry, your browser doesn't support embedded videos.
</video>

Cover

video{
   object-fit: cover; /*to cover all the box*/
}

Fill

video{
   object-fit: fill; /*to add black content at top and bottom*/
   object-position: 0 -14px; /* to center our image*/
}

Note that the video controls are over our image, so our image is not completly showed. If you are using object-fit cover, edit your image on a visual app as photoshop and add a margin bottom content.

Change the Blank Cells to "NA"

This works for me.

dataset <- read.csv(file = "data.csv",header=TRUE,fill = T,na.strings = "")

Check if table exists without using "select from"

Just to add an extra way to do it, and depending on what you need it for you could use a handler for er_no_such_table error:1146 like this:

DELIMITER ;;
CREATE PROCEDURE `insert_in_my_table`(in my_var INT)
BEGIN
   -- Error number for table not found
   DECLARE CONTINUE HANDLER FOR 1146
   BEGIN
      -- table doesn't exists, do something...
      CREATE TABLE my_table(n INT);
      INSERT INTO my_table (n) values(my_var);
   END;
      -- table does exists, do something...
      INSERT INTO my_table (n) values(my_var);
END ;;
DELIMITER ;

CSS: how do I create a gap between rows in a table?

This is the way (I was thinking it's impossible):

First give the table only vertical border-spacing (for example 5px) and set it's horizontal border-spacing to 0. Then you should give proper borders to each row cell. For example the right-most cell in each row should have border on top, bottom and right. The left-most cells should have border on top, bottom and left. And the other cells between these 2 should only have border on top and bottom. Like this example:

<table style="border-spacing:0 5px; color:black">
    <tr>
        <td style="border-bottom:thin black solid; border-top:thin black solid; border-left:thin black solid;">left-most cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid; border-right:thin black solid;">right-most cell</td>
    </tr>
    <tr>
        <td style="border-bottom:thin black solid; border-top:thin black solid; border-left:thin black solid;">left-most cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid; border-right:thin black solid;">right-most cell</td>
    </tr>
    <tr>
        <td style="border-bottom:thin black solid; border-top:thin black solid; border-left:thin black solid;">left-most cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid;">other cell</td>
        <td style="border-bottom:thin black solid; border-top:thin black solid; border-right:thin black solid;">right-most cell</td>
    </tr>
</table>

How to increase MaximumErrorCount in SQL Server 2008 Jobs or Packages?

It is important to highlight that the Property (MaximumErrorCount) that needs to be changed must be set as more than 0 (which is the default) in the Package level and not in the specific control that is showing the error (I tried this and it does not work!)

Be sure that in the Properties Window, the Pull down menu is set to "Package", then look for the property MaximumErrorCount to change it.

Java check if boolean is null

boolean is a primitive type, and therefore can not be null.

Its boxed type, Boolean, can be null.

The function is probably returning a Boolean as opposed to a boolean, so assigning the result to a Boolean-type variable will allow you to test for nullity.

Run all SQL files in a directory

@echo off
cd C:\Program Files (x86)\MySQL\MySQL Workbench 6.0 CE

for %%a in (D:\abc\*.sql) do (
echo %%a
mysql --host=ip --port=3306 --user=uid--password=ped < %%a
)

Step1: above lines copy into note pad save it as bat.

step2: In d drive abc folder in all Sql files in queries executed in sql server.

step3: Give your ip, user id and password.

Resource blocked due to MIME type mismatch (X-Content-Type-Options: nosniff)

This might be because the browser cannot access a file. I stumbled with this type of error when creating application with node.js. You can try to directly request the script file (copying and pasting url) and see if you can retrieve it. You can see then what the real problem is. It can be because of permission of folder in which the file is located, or browser just cannot find it due to incorrect path to it. In node.js, after specifying route to file, all works.

How to echo xml file in php

Here's what worked for me:

<pre class="prettyprint linenums">
    <code class="language-xml"><?php echo htmlspecialchars(file_get_contents("example.xml"), ENT_QUOTES); ?></code>
</pre>

Using htmlspecialchars will prevent tags from being displayed as html and won't break anything. Note that I'm using Prettyprint to highlight the code ;)

how to use "AND", "OR" for RewriteCond on Apache?

This is an interesting question and since it isn't explained very explicitly in the documentation I'll answer this by going through the sourcecode of mod_rewrite; demonstrating a big benefit of open-source.

In the top section you'll quickly spot the defines used to name these flags:

#define CONDFLAG_NONE               1<<0
#define CONDFLAG_NOCASE             1<<1
#define CONDFLAG_NOTMATCH           1<<2
#define CONDFLAG_ORNEXT             1<<3
#define CONDFLAG_NOVARY             1<<4

and searching for CONDFLAG_ORNEXT confirms that it is used based on the existence of the [OR] flag:

else if (   strcasecmp(key, "ornext") == 0
         || strcasecmp(key, "OR") == 0    ) {
    cfg->flags |= CONDFLAG_ORNEXT;
}

The next occurrence of the flag is the actual implementation where you'll find the loop that goes through all the RewriteConditions a RewriteRule has, and what it basically does is (stripped, comments added for clarity):

# loop through all Conditions that precede this Rule
for (i = 0; i < rewriteconds->nelts; ++i) {
    rewritecond_entry *c = &conds[i];

    # execute the current Condition, see if it matches
    rc = apply_rewrite_cond(c, ctx);

    # does this Condition have an 'OR' flag?
    if (c->flags & CONDFLAG_ORNEXT) {
        if (!rc) {
            /* One condition is false, but another can be still true. */
            continue;
        }
        else {
            /* skip the rest of the chained OR conditions */
            while (   i < rewriteconds->nelts
                   && c->flags & CONDFLAG_ORNEXT) {
                c = &conds[++i];
            }
        }
    }
    else if (!rc) {
        return 0;
    }
}

You should be able to interpret this; it means that OR has a higher precedence, and your example indeed leads to if ( (A OR B) AND (C OR D) ). If you would, for example, have these Conditions:

RewriteCond A [or]
RewriteCond B [or]
RewriteCond C
RewriteCond D

it would be interpreted as if ( (A OR B OR C) and D ).

Installing Git on Eclipse

There are two ways of installing the Git plugin in Eclipse

Installing through Help -> Install New Software..., then add the location http://download.eclipse.org/egit/updates/
Installing through Help -> Eclipse Marketplace..., then type Egit and installing it.

Both methods may need you to restart Eclipse in the middle. For the step by step guide on installing and configuring Git plugin in Eclipse, you can also refer to Install and configure git plugin in Eclipse

printf format specifiers for uint32_t and size_t

Sounds like you're expecting size_t to be the same as unsigned long (possibly 64 bits) when it's actually an unsigned int (32 bits). Try using %zu in both cases.

I'm not entirely certain though.

Link to a section of a webpage

The fragment identifier (also known as: Fragment IDs, Anchor Identifiers, Named Anchors) introduced by a hash mark # is the optional last part of a URL for a document. It is typically used to identify a portion of that document.

<a href="http://www.someuri.com/page#fragment">Link to fragment identifier</a>

Syntax for URIs also allows an optional query part introduced by a question mark ?. In URIs with a query and a fragment the fragment follows the query.

<a href="http://www.someuri.com/page?query=1#fragment">Link to fragment with a query</a>

When a Web browser requests a resource from a Web server, the agent sends the URI to the server, but does not send the fragment. Instead, the agent waits for the server to send the resource, and then the agent (Web browser) processes the resource according to the document type and fragment value.

Named Anchors <a name="fragment"> are deprecated in XHTML 1.0, the ID attribute is the suggested replacement. <div id="fragment"></div>

getting the screen density programmatically in android?

Yet another answer:

/**
* @return "ldpi", "mdpi", "hdpi", "xhdpi", "xhdpi", "xxhdpi", "xxxhdpi", "tvdpi", or "unknown".
*/
public static String getDensityBucket(Resources resources) {
    switch (resources.getDisplayMetrics().densityDpi) {
        case DisplayMetrics.DENSITY_LOW:
            return "ldpi";
        case DisplayMetrics.DENSITY_MEDIUM:
            return "mdpi";
        case DisplayMetrics.DENSITY_HIGH:
            return "hdpi";
        case DisplayMetrics.DENSITY_XHIGH:
            return "xhdpi";
        case DisplayMetrics.DENSITY_XXHIGH:
            return "xxhdpi";
        case DisplayMetrics.DENSITY_XXXHIGH:
            return "xxxhdpi";
        case DisplayMetrics.DENSITY_TV:
            return "tvdpi";
        default:
            return "unknown";
    }
}

How to get input from user at runtime

SQL> DECLARE
  2     a integer;
  3     b integer;
  4  BEGIN
  5     a:=&a;
  6     b:=&b;
  7     dbms_output.put_line('The a value is : ' || a);
  8     dbms_output.put_line('The b value is : ' || b);
  9  END;
 10  /

How to use BigInteger?

BigInteger is immutable. The javadocs states that add() "[r]eturns a BigInteger whose value is (this + val)." Therefore, you can't change sum, you need to reassign the result of the add method to sum variable.

sum = sum.add(BigInteger.valueOf(i));

How to start activity in another application?

If you guys are facing "Permission Denial: starting Intent..." error or if the app is getting crash without any reason during launching the app - Then use this single line code in Manifest

android:exported="true"

Please be careful with finish(); , if you missed out it the app getting frozen. if its mentioned the app would be a smooth launcher.

finish();

The other solution only works for two activities that are in the same application. In my case, application B doesn't know class com.example.MyExampleActivity.class in the code, so compile will fail.

I searched on the web and found something like this below, and it works well.

Intent intent = new Intent();
intent.setComponent(new ComponentName("com.example", "com.example.MyExampleActivity"));
startActivity(intent);

You can also use the setClassName method:

Intent intent = new Intent(Intent.ACTION_MAIN);
intent.setClassName("com.hotfoot.rapid.adani.wheeler.android", "com.hotfoot.rapid.adani.wheeler.android.view.activities.MainActivity");
startActivity(intent);
finish();

You can also pass the values from one app to another app :

Intent launchIntent = getApplicationContext().getPackageManager().getLaunchIntentForPackage("com.hotfoot.rapid.adani.wheeler.android.LoginActivity");
if (launchIntent != null) {
    launchIntent.putExtra("AppID", "MY-CHILD-APP1");
    launchIntent.putExtra("UserID", "MY-APP");
    launchIntent.putExtra("Password", "MY-PASSWORD");
    startActivity(launchIntent);
    finish();
} else {
    Toast.makeText(getApplicationContext(), " launch Intent not available", Toast.LENGTH_SHORT).show();
}

Getting the array length of a 2D array in Java

public class Array_2D {
int arr[][];
public Array_2D() {
    Random r=new Random(10);
     arr = new int[5][10];
     for(int i=0;i<5;i++)
     {
         for(int j=0;j<10;j++)
         {
             arr[i][j]=(int)r.nextInt(10);
         }
     }
 }
  public void display()
  {
         for(int i=0;i<5;i++)

         {
             for(int j=0;j<10;j++)
             {
                 System.out.print(arr[i][j]+" "); 
             }
             System.out.println("");
         }
   }
     public static void main(String[] args) {
     Array_2D s=new Array_2D();
     s.display();
   }  
  }

How to multiply duration by integer?

For multiplication of variable to time.Second using following code

    oneHr:=3600
    addOneHrDuration :=time.Duration(oneHr)
    addOneHrCurrTime := time.Now().Add(addOneHrDuration*time.Second)

Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:compile (default-compile)

We tried everything listed so far and it still failed. The error also mentioned

(default-war) on project utilsJava: Error assembling WAR: webxml attribute is required

The solution that finally fixed it was adding this to POM:

<failOnMissingWebXml>false</failOnMissingWebXml>

As mentioned here Error assembling WAR - webxml attribute is required

Our POM now contains this:

<plugin>
<inherited>true</inherited>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>${maven-war-plugin.version}</version>
<configuration>
<failOnMissingWebXml>false</failOnMissingWebXml>
<warName>${project.artifactId}</warName>
<attachClasses>true</attachClasses>
</configuration>
</plugin>

Java: object to byte[] and byte[] to object converter (for Tokyo Cabinet)

public static byte[] serialize(Object obj) throws IOException {
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    ObjectOutputStream os = new ObjectOutputStream(out);
    os.writeObject(obj);
    return out.toByteArray();
}
public static Object deserialize(byte[] data) throws IOException, ClassNotFoundException {
    ByteArrayInputStream in = new ByteArrayInputStream(data);
    ObjectInputStream is = new ObjectInputStream(in);
    return is.readObject();
}

Why can't I initialize non-const static member or static array in class?

I think it's to prevent you from mixing declarations and definitions. (Think about the problems that could occur if you include the file in multiple places.)

How to set UITextField height?

You can not change the height of the rounded rect border style. To set the height, just choose any border style other than rounded border in Xcode:

enter image description here

IOError: [Errno 22] invalid mode ('r') or filename: 'c:\\Python27\test.txt'

always use 'r' to get a raw string when you want to avoid escape.

test_file=open(r'c:\Python27\test.txt','r')

where does MySQL store database files?

WAMP stores the db data under WAMP\bin\mysql\mysql(version)\data. Where the WAMP folder itself is depends on where you installed it to (on xp, I believe it is directly in the main drive, for example c:\WAMP\...

If you deleted that folder, or if the uninstall deleted that folder, if you did not do a DB backup before the uninstall, you may be out of luck.

If you did do a backup though phpmyadmin, then login, and click the import tab, and browse to the backup file.

What is the difference between a definition and a declaration?

Stages of an executable generation:

(1) pre-processor -> (2) translator/compiler -> (3) linker

In stage 2 (translator/compiler), declaration statements in our code tell to the compiler that these things we are going to use in future and you can find definition later, meaning is :

translator make sure that : what is what ? means declaration

and (3) stage (linker) needs definition to bind the things

Linker make sure that : where is what ? means definition

window.location.href doesn't redirect

In my case it is working as expected for all browsers after setting time interval.

setTimeout(function(){document.location.href = "myNextPage.html;"},100);

Copy all files with a certain extension from all subdirectories

From all of the above, I came up with this version. This version also works for me in the mac recovery terminal.

find ./ -name '*.xsl' -exec cp -prv '{}' '/path/to/targetDir/' ';'

It will look in the current directory and recursively in all of the sub directories for files with the xsl extension. It will copy them all to the target directory.

cp flags are:

p - preserve attributes of the file
r - recursive
v - verbose (shows you whats being copied)

git submodule tracking latest

Edit (2020.12.28): GitHub change default master branch to main branch since October 2020. See https://github.com/github/renaming

Update March 2013

Git 1.8.2 added the possibility to track branches.

"git submodule" started learning a new mode to integrate with the tip of the remote branch (as opposed to integrating with the commit recorded in the superproject's gitlink).

# add submodule to track master branch
git submodule add -b master [URL to Git repo];

# update your submodule
git submodule update --remote

If you had a submodule already present you now wish would track a branch, see "how to make an existing submodule track a branch".

Also see Vogella's tutorial on submodules for general information on submodules.

Note:

git submodule add -b . [URL to Git repo];
                    ^^^

See git submodule man page:

A special value of . is used to indicate that the name of the branch in the submodule should be the same name as the current branch in the current repository.

See commit b928922727d6691a3bdc28160f93f25712c565f6:

`submodule add`: If `--branch` is given, record it in `.gitmodules`

This allows you to easily record a submodule.<name>.branch option in .gitmodules when you add a new submodule. With this patch,

$ git submodule add -b <branch> <repository> [<path>]
$ git config -f .gitmodules submodule.<path>.branch <branch>

reduces to

$ git submodule add -b <branch> <repository> [<path>]

This means that future calls to

$ git submodule update --remote ...

will get updates from the same branch that you used to initialize the submodule, which is usually what you want.

Signed-off-by: W. Trevor King [email protected]

Original answer (February 2012):

A submodule is a single commit referenced by a parent repo.
Since it is a Git repo on its own, the "history of all commits" is accessible through a git log within that submodule.

So for a parent to track automatically the latest commit of a given branch of a submodule, it would need to:

cd in the submodule
git fetch/pull to make sure it has the latest commits on the right branch
cd back in the parent repo
add and commit in order to record the new commit of the submodule.

gitslave (that you already looked at) seems to be the best fit, including for the commit operation.

It is a little annoying to make changes to the submodule due to the requirement to check out onto the correct submodule branch, make the change, commit, and then go into the superproject and commit the commit (or at least record the new location of the submodule).

Other alternatives are detailed here.

How do I set up access control in SVN?

In your svn\repos\YourRepo\conf folder you will find two files, authz and passwd. These are the two you need to adjust.

In the passwd file you need to add some usernames and passwords. I assume you have already done this since you have people using it:

[users]
User1=password1
User2=password2

Then you want to assign permissions accordingly with the authz file:

Create the conceptual groups you want, and add people to it:

[groups]
allaccess = user1
someaccess = user2

Then choose what access they have from both the permissions and project level.

So let's give our "all access" guys all access from the root:

[/]
@allaccess = rw

But only give our "some access" guys read-only access to some lower level project:

[/someproject]
@someaccess = r

You will also find some simple documentation in the authz and passwd files.

How do I kill all the processes in Mysql "show processlist"?

If you are using laravel then this is for you:

$query = "SHOW FULL PROCESSLIST";
    $results = DB::select(DB::raw($query));

    foreach($results as $result){
        if($result->Command == "Sleep"){
            $sql="KILL ". $result->Id;
            DB::select(DB::raw($sql));
        }
    }

Of-course, you should use this use Illuminate\Support\Facades\DB; after your namespace.

Which selector do I need to select an option by its text?

You can use the :contains() selector to select elements that contain specific text.
For example:

$('#mySelect option:contains(abc)')

To check whether a given <select> element has such an option, use the .has() method:

if (mySelect.has('option:contains(abc)').length)

To find all <select>s that contain such an option, use the :has() selector:

$('select:has(option:contains(abc))')

Failed to load c++ bson extension

For my case, I npm install all modules on my local machine (Mac), and I did not include node_modules in .gitignore and uploaded to github. Then I cloned the project to my aws, as you know, it is running Linux, so I got the errors. What I did is just include node_modules in .gitignore, and use npm install in my aws instance, then it works.

Passing an array to a query using a WHERE clause

Below is the method I have used, using PDO with named placeholders for other data. To overcome SQL injection I am filtering the array to accept only the values that are integers and rejecting all others.

$owner_id = 123;
$galleries = array(1,2,5,'abc');

$good_galleries = array_filter($chapter_arr, 'is_numeric');

$sql = "SELECT * FROM galleries WHERE owner=:OWNER_ID AND id IN ($good_galleries)";
$stmt = $dbh->prepare($sql);
$stmt->execute(array(
    "OWNER_ID" => $owner_id,
));

$data = $stmt->fetchAll(PDO::FETCH_ASSOC);

Is there a CSS parent selector?

Changing parent element based on child element can currently only happen when we have an <input> element inside the parent element. When an input gets focus, its corresponding parent element can get affected using CSS.

Following example will help you understand using :focus-within in CSS.

_x000D_

.outer-div {_x000D_
  width: 400px;_x000D_
  height: 400px;_x000D_
  padding: 50px;_x000D_
  float: left_x000D_
}_x000D_
_x000D_
.outer-div:focus-within {_x000D_
  background: red;_x000D_
}_x000D_
_x000D_
.inner-div {_x000D_
  width: 200px;_x000D_
  height: 200px;_x000D_
  float: left;_x000D_
  background: yellow;_x000D_
  padding: 50px;_x000D_
}

_x000D_

<div class="outer-div">_x000D_
  <div class="inner-div">_x000D_
    I want to change outer-div(Background color) class based on inner-div. Is it possible?_x000D_
    <input type="text" placeholder="Name" />_x000D_
  </div>_x000D_
</div>

_x000D_

Best way to log POST data in Apache?

I would do it in the application, actually. It's still configurable at runtime, depending on your logger system, of course. For example, if you use Apache Log (log4j/cxx) you could configure a dedicated logger for such URLs and then configure it at runtime from an XML file.

How to enable Ad Hoc Distributed Queries

sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'Ad Hoc Distributed Queries', 1;
GO
RECONFIGURE;
GO

Vertical align in bootstrap table

Based on what you have provided your CSS selector is not specific enough to override the CSS rules defined by Bootstrap.

Try this:

.table > tbody > tr > td {
     vertical-align: middle;
}

In Boostrap 4, this can be achieved with the .align-middle Vertical Alignment utility class.

<td class="align-middle">Text</td>

How can I check if the array of objects have duplicate property values?

Try an simple loop:

var repeat = [], tmp, i = 0;

while(i < values.length){
  repeat.indexOf(tmp = values[i++].name) > -1 ? values.pop(i--) : repeat.push(tmp)
}

Demo

What is the 'dynamic' type in C# 4.0 used for?

The dynamic keyword is new to C# 4.0, and is used to tell the compiler that a variable's type can change or that it is not known until runtime. Think of it as being able to interact with an Object without having to cast it.

dynamic cust = GetCustomer();
cust.FirstName = "foo"; // works as expected
cust.Process(); // works as expected
cust.MissingMethod(); // No method found!

Notice we did not need to cast nor declare cust as type Customer. Because we declared it dynamic, the runtime takes over and then searches and sets the FirstName property for us. Now, of course, when you are using a dynamic variable, you are giving up compiler type checking. This means the call cust.MissingMethod() will compile and not fail until runtime. The result of this operation is a RuntimeBinderException because MissingMethod is not defined on the Customer class.

The example above shows how dynamic works when calling methods and properties. Another powerful (and potentially dangerous) feature is being able to reuse variables for different types of data. I'm sure the Python, Ruby, and Perl programmers out there can think of a million ways to take advantage of this, but I've been using C# so long that it just feels "wrong" to me.

dynamic foo = 123;
foo = "bar";

OK, so you most likely will not be writing code like the above very often. There may be times, however, when variable reuse can come in handy or clean up a dirty piece of legacy code. One simple case I run into often is constantly having to cast between decimal and double.

decimal foo = GetDecimalValue();
foo = foo / 2.5; // Does not compile
foo = Math.Sqrt(foo); // Does not compile
string bar = foo.ToString("c");

The second line does not compile because 2.5 is typed as a double and line 3 does not compile because Math.Sqrt expects a double. Obviously, all you have to do is cast and/or change your variable type, but there may be situations where dynamic makes sense to use.

dynamic foo = GetDecimalValue(); // still returns a decimal
foo = foo / 2.5; // The runtime takes care of this for us
foo = Math.Sqrt(foo); // Again, the DLR works its magic
string bar = foo.ToString("c");

SQL update statement in C#

String st = "UPDATE supplier SET supplier_id = " + textBox1.Text + ", supplier_name = " + textBox2.Text
            + "WHERE supplier_id = " + textBox1.Text;

        SqlCommand sqlcom = new SqlCommand(st, myConnection);
        try
        {
            sqlcom.ExecuteNonQuery();
            MessageBox.Show("update successful");
        }
        catch (SqlException ex)
        {
            MessageBox.Show(ex.Message);
        }

load jquery after the page is fully loaded

You can either use .onload function. It runs a function when the page is fully loaded including graphics.

window.onload=function(){
      // Run code
    };

Or another way is : Include scripts at the bottom of your page.

Error: Expression must have integral or unscoped enum type

Your variable size is declared as: float size;

You can't use a floating point variable as the size of an array - it needs to be an integer value.

You could cast it to convert to an integer:

float *temp = new float[(int)size];

Your other problem is likely because you're writing outside of the bounds of the array:

   float *temp = new float[size];

    //Getting input from the user
    for (int x = 1; x <= size; x++){
        cout << "Enter temperature " << x << ": ";

        // cin >> temp[x];
        // This should be:
        cin >> temp[x - 1];
    }

Arrays are zero based in C++, so this is going to write beyond the end and never write the first element in your original code.

Why do I have to "git push --set-upstream origin <branch>"?

TL;DR: `git branch --set-upstream-to origin/solaris`

The answer to the question you asked—which I'll rephrase a bit as "do I have to set an upstream"—is: no, you don't have to set an upstream at all.

If you do not have upstream for the current branch, however, Git changes its behavior on git push, and on other commands as well.

The complete push story here is long and boring and goes back in history to before Git version 1.5. To shorten it a whole lot, git push was implemented poorly.¹ As of Git version 2.0, Git now has a configuration knob spelled push.default which now defaults to simple. For several versions of Git before and after 2.0, every time you ran git push, Git would spew lots of noise trying to convince you to set push.default just to get git push to shut up.

You do not mention which version of Git you are running, nor whether you have configured push.default, so we must guess. My guess is that you are using Git version 2-point-something, and that you have set push.default to simple to get it to shut up. Precisely which version of Git you have, and what if anything you have push.default set to, does matter, due to that long and boring history, but in the end, the fact that you're getting yet another complaint from Git indicates that your Git is configured to avoid one of the mistakes from the past.

What is an upstream?

An upstream is simply another branch name, usually a remote-tracking branch, associated with a (regular, local) branch.

Every branch has the option of having one (1) upstream set. That is, every branch either has an upstream, or does not have an upstream. No branch can have more than one upstream.

The upstream should, but does not have to be, a valid branch (whether remote-tracking like origin/B or local like master). That is, if the current branch B has upstream U, git rev-parse U should work. If it does not work—if it complains that U does not exist—then most of Git acts as though the upstream is not set at all. A few commands, like git branch -vv, will show the upstream setting but mark it as "gone".

What good is an upstream?

If your push.default is set to simple or upstream, the upstream setting will make git push, used with no additional arguments, just work.

That's it—that's all it does for git push. But that's fairly significant, since git push is one of the places where a simple typo causes major headaches.

If your push.default is set to nothing, matching, or current, setting an upstream does nothing at all for git push.

(All of this assumes your Git version is at least 2.0.)

The upstream affects `git fetch`

If you run git fetch with no additional arguments, Git figures out which remote to fetch from by consulting the current branch's upstream. If the upstream is a remote-tracking branch, Git fetches from that remote. (If the upstream is not set or is a local branch, Git tries fetching origin.)

The upstream affects `git merge` and `git rebase` too

If you run git merge or git rebase with no additional arguments, Git uses the current branch's upstream. So it shortens the use of these two commands.

The upstream affects `git pull`

You should never² use git pull anyway, but if you do, git pull uses the upstream setting to figure out which remote to fetch from, and then which branch to merge or rebase with. That is, git pull does the same thing as git fetch—because it actually runs git fetch—and then does the same thing as git merge or git rebase, because it actually runs git merge or git rebase.

(You should usually just do these two steps manually, at least until you know Git well enough that when either step fails, which they will eventually, you recognize what went wrong and know what to do about it.)

The upstream affects `git status`

This may actually be the most important. Once you have an upstream set, git status can report the difference between your current branch and its upstream, in terms of commits.

If, as is the normal case, you are on branch B with its upstream set to origin/B, and you run git status, you will immediately see whether you have commits you can push, and/or commits you can merge or rebase onto.

This is because git status runs:

git rev-list --count @{u}..HEAD: how many commits do you have on B that are not on origin/B?
git rev-list --count HEAD..@{u}: how many commits do you have on origin/B that are not on B?

Setting an upstream gives you all of these things.

How come `master` already has an upstream set?

When you first clone from some remote, using:

$ git clone git://some.host/path/to/repo.git

or similar, the last step Git does is, essentially, git checkout master. This checks out your local branch master—only you don't have a local branch master.

On the other hand, you do have a remote-tracking branch named origin/master, because you just cloned it.

Git guesses that you must have meant: "make me a new local master that points to the same commit as remote-tracking origin/master, and, while you're at it, set the upstream for master to origin/master."

This happens for every branch you git checkout that you do not already have. Git creates the branch and makes it "track" (have as an upstream) the corresponding remote-tracking branch.

But this doesn't work for new branches, i.e., branches with no remote-tracking branch yet.

If you create a new branch:

$ git checkout -b solaris

there is, as yet, no origin/solaris. Your local solaris cannot track remote-tracking branch origin/solaris because it does not exist.

When you first push the new branch:

$ git push origin solaris

that creates solaris on origin, and hence also creates origin/solaris in your own Git repository. But it's too late: you already have a local solaris that has no upstream.³

Shouldn't Git just set that, now, as the upstream automatically?

Probably. See "implemented poorly" and footnote 1. It's hard to change now: There are millions⁴ of scripts that use Git and some may well depend on its current behavior. Changing the behavior requires a new major release, nag-ware to force you to set some configuration field, and so on. In short, Git is a victim of its own success: whatever mistakes it has in it, today, can only be fixed if the change is either mostly invisible, clearly-much-better, or done slowly over time.

The fact is, it doesn't today, unless you use --set-upstream or -u during the git push. That's what the message is telling you.

You don't have to do it like that. Well, as we noted above, you don't have to do it at all, but let's say you want an upstream. You have already created branch solaris on origin, through an earlier push, and as your git branch output shows, you already have origin/solaris in your local repository.

You just don't have it set as the upstream for solaris.

To set it now, rather than during the first push, use git branch --set-upstream-to. The --set-upstream-to sub-command takes the name of any existing branch, such as origin/solaris, and sets the current branch's upstream to that other branch.

That's it—that's all it does—but it has all those implications noted above. It means you can just run git fetch, then look around, then run git merge or git rebase as appropriate, then make new commits and run git push, without a bunch of additional fussing-around.

¹To be fair, it was not clear back then that the initial implementation was error-prone. That only became clear when every new user made the same mistakes every time. It's now "less poor", which is not to say "great".

²"Never" is a bit strong, but I find that Git newbies understand things a lot better when I separate out the steps, especially when I can show them what git fetch actually did, and they can then see what git merge or git rebase will do next.

³If you run your first git push as git push -u origin solaris—i.e., if you add the -u flag—Git will set origin/solaris as the upstream for your current branch if (and only if) the push succeeds. So you should supply -u on the first push. In fact, you can supply it on any later push, and it will set or change the upstream at that point. But I think git branch --set-upstream-to is easier, if you forgot.

⁴Measured by the Austin Powers / Dr Evil method of simply saying "one MILLLL-YUN", anyway.

Setting unique Constraint with fluent API?

@coni2k 's answer is correct however you must add [StringLength] attribute for it to work otherwise you will get an invalid key exception (Example bellow).

[StringLength(65)]
[Index("IX_FirstNameLastName", 1, IsUnique = true)]
public string FirstName { get; set; }

[StringLength(65)]
[Index("IX_FirstNameLastName", 2, IsUnique = true)]
public string LastName { get; set; }

Accessing a Shared File (UNC) From a Remote, Non-Trusted Domain With Credentials

AFAIK, you don't need to map the UNC path to a drive letter in order to establish credentials for a server. I regularly used batch scripts like:

net use \\myserver /user:username password

:: do something with \\myserver\the\file\i\want.xml

net use /delete \\my.server.com

However, any program running on the same account as your program would still be able to access everything that username:password has access to. A possible solution could be to isolate your program in its own local user account (the UNC access is local to the account that called NET USE).

Note: Using SMB accross domains is not quite a good use of the technology, IMO. If security is that important, the fact that SMB lacks encryption is a bit of a damper all by itself.

Download multiple files with a single action

Here is the way I do that. I open multiple ZIP but also other kind of data (I export projet in PDF and at same time many ZIPs with document).

I just copy past part of my code. The call from a button in a list:

$url_pdf = "pdf.php?id=7";
$url_zip1 = "zip.php?id=8";
$url_zip2 = "zip.php?id=9";
$btn_pdf = "<a href=\"javascript:;\" onClick=\"return open_multiple('','".$url_pdf.",".$url_zip1.",".$url_zip2."');\">\n";
$btn_pdf .= "<img src=\"../../../images/icones/pdf.png\" alt=\"Ver\">\n";
$btn_pdf .= "</a>\n"

So a basic call to a JS routine (Vanilla rules!). here is the JS routine:

 function open_multiple(base,url_publication)
 {
     // URL of pages to open are coma separated
     tab_url = url_publication.split(",");
     var nb = tab_url.length;
     // Loop against URL    
     for (var x = 0; x < nb; x++)
     {
        window.open(tab_url[x]);
      }

     // Base is the dest of the caller page as
     // sometimes I need it to refresh
     if (base != "")
      {
        window.location.href  = base;
      }
   }

The trick is to NOT give the direct link of the ZIP file but to send it to the browser. Like this:

  $type_mime = "application/zip, application/x-compressed-zip";
 $the_mime = "Content-type: ".$type_mime;
 $tdoc_size = filesize ($the_zip_path);
 $the_length = "Content-Length: " . $tdoc_size;
 $tdoc_nom = "Pesquisa.zip";
 $the_content_disposition = "Content-Disposition: attachment; filename=\"".$tdoc_nom."\"";

  header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1
  header("Expires: Sat, 26 Jul 1997 05:00:00 GMT");   // Date in the past
  header($the_mime);
  header($the_length);
  header($the_content_disposition);

  // Clear the cache or some "sh..." will be added
  ob_clean();
  flush();
  readfile($the_zip_path);
  exit();

Jquery Value match Regex

Pass a string to RegExp or create a regex using the // syntax
Call regex.test(string), not string.test(regex)

jQuery(function () {
    $(".mail").keyup(function () {
        var VAL = this.value;

        var email = new RegExp('^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$');

        if (email.test(VAL)) {
            alert('Great, you entered an E-Mail-address');
        }
    });
});

$(document).click() not working correctly on iPhone. jquery

try this, applies only to iPhone and iPod so you're not making everything turn blue on chrome or firefox mobile;

/iP/i.test(navigator.userAgent) && $('*').css('cursor', 'pointer');

basically, on iOS, things aren't "clickable" by default -- they're "touchable" (pfffff) so you make them "clickable" by giving them a pointer cursor. makes total sense, right??

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

This might help too:

Post.order(created_at: :desc)

postgresql - replace all instances of a string within text field

The Regular Expression Way

If you need stricter replacement matching, PostgreSQL's regexp_replace function can match using POSIX regular expression patterns. It has the syntax regexp_replace(source, pattern, replacement [, flags ]).

I will use flags i and g for case-insensitive and global matching, respectively. I will also use \m and \M to match the beginning and the end of a word, respectively.

There are usually quite a few gotchas when performing regex replacment. Let's see how easy it is to replace a cat with a dog.

SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat', 'dog');
-->                    Cat bobdog cat cats catfish

SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat', 'dog', 'i');
-->                    dog bobcat cat cats catfish

SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat', 'dog', 'g');
-->                    Cat bobdog dog dogs dogfish

SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat', 'dog', 'gi');
-->                    dog bobdog dog dogs dogfish

SELECT regexp_replace('Cat bobcat cat cats catfish', '\mcat', 'dog', 'gi');
-->                    dog bobcat dog dogs dogfish

SELECT regexp_replace('Cat bobcat cat cats catfish', 'cat\M', 'dog', 'gi');
-->                    dog bobdog dog cats catfish

SELECT regexp_replace('Cat bobcat cat cats catfish', '\mcat\M', 'dog', 'gi');
-->                    dog bobcat dog cats catfish

SELECT regexp_replace('Cat bobcat cat cats catfish', '\mcat(s?)\M', 'dog\1', 'gi');
-->                    dog bobcat dog dogs catfish

Even after all of that, there is at least one unresolved condition. For example, sentences that begin with "Cat" will be replaced with lower-case "dog" which break sentence capitalization.

Check out the current PostgreSQL pattern matching docs for all the details.

Update entire column with replacement text

Given my examples, maybe the safest option would be:

UPDATE table SET field = regexp_replace(field, '\mcat\M', 'dog', 'gi');

How do I redirect users after submit button click?

Your submission will cancel the redirect or vice versa.

I do not see the reason for the redirect in the first place since why do you have an order form that does nothing.

That said, here is how to do it. Firstly NEVER put code on the submit button but do it in the onsubmit, secondly return false to stop the submission

NOTE This code will IGNORE the action and ONLY execute the script due to the return false/preventDefault

function redirect() {
  window.location.replace("login.php");
  return false;
}

using

<form name="form1" id="form1" method="post" onsubmit="return redirect()">  
  <input type="submit" class="button4" name="order" id="order" value="Place Order" >
</form>

Or unobtrusively:

window.onload=function() {
  document.getElementById("form1").onsubmit=function() {
    window.location.replace("login.php");
    return false;
  }
}

using

<form id="form1" method="post">  
  <input type="submit" class="button4" value="Place Order" >
</form>

jQuery:

$("#form1").on("submit",function(e) {
   e.preventDefault(); // cancel submission
   window.location.replace("login.php");
});

-----

Example:

_x000D_

$("#form1").on("submit", function(e) {_x000D_
  e.preventDefault(); // cancel submission_x000D_
  alert("this could redirect to login.php"); _x000D_
});

_x000D_

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"></script>_x000D_
_x000D_
_x000D_
<form id="form1" method="post" action="javascript:alert('Action!!!')">_x000D_
  <input type="submit" class="button4" value="Place Order">_x000D_
</form>

_x000D_

What does "async: false" do in jQuery.ajax()?

If you disable asynchronous retrieval, your script will block until the request has been fulfilled. It's useful for performing some sequence of requests in a known order, though I find async callbacks to be cleaner.

Differences between strong and weak in Objective-C

To understand Strong and Weak reference consider below example, suppose we have method named as displayLocalVariable.

 -(void)displayLocalVariable
  {
     UIView* myView = [[UIView alloc] init];
     NSLog(@"myView tag is = %ld", myView.tag);
  }

In above method scope of myView variable is limited to displayLocalVariable method, once the method gets finished myView variable which is holding the UIView object will get deallocated from the memory.

Now what if we want to hold the myView variable throughout our view controller's life cycle. For this we can create the property named as usernameView which will have Strong reference to the variable myView(see @property(nonatomic,strong) UIView* usernameView; and self.usernameView = myView; in below code), as below,

@interface LoginViewController ()

@property(nonatomic,strong) UIView* usernameView;
@property(nonatomic,weak) UIView* dummyNameView;

- (void)displayLocalVariable;

@end

@implementation LoginViewController

- (void)viewDidLoad
{
    [super viewDidLoad];

}

-(void)viewWillAppear:(BOOL)animated
{
     [self displayLocalVariable];
}

- (void)displayLocalVariable
{
   UIView* myView = [[UIView alloc] init];
   NSLog(@"myView tag is = %ld", myView.tag);
   self.usernameView = myView;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}


@end

Now in above code you can see myView has been assigned to self.usernameView and self.usernameView is having a strong reference(as we declared in interface using @property) to myView. Hence myView will not get deallocated from memory till self.usernameView is alive.

Weak reference

Now consider assigning myName to dummyNameView which is a Weak reference, self.dummyNameView = myView; Unlike Strong reference Weak will hold the myView only till there is Strong reference to myView. See below code to understand Weak reference,

-(void)displayLocalVariable
  {
     UIView* myView = [[UIView alloc] init];
     NSLog(@"myView tag is = %ld", myView.tag);
     self.dummyNameView = myView;
  }

In above code there is Weak reference to myView(i.e. self.dummyNameView is having Weak reference to myView) but there is no Strong reference to myView, hence self.dummyNameView will not be able to hold the myView value.

Now again consider the below code,

-(void)displayLocalVariable
      {
         UIView* myView = [[UIView alloc] init];
         NSLog(@"myView tag is = %ld", myView.tag);
         self.usernameView = myView;
         self.dummyNameView = myView;
      }

In above code self.usernameView has a Strong reference to myView, hence self.dummyNameView will now have a value of myView even after method ends since myView has a Strong reference associated with it.

Now whenever we make a Strong reference to a variable it's retain count get increased by one and the variable will not get deallocated till it's retain count reaches to 0.

Hope this helps.

How to make UIButton's text alignment center? Using IB

For Swift 4:

@IBAction func myButton(sender: AnyObject) {
    sender.titleLabel?.textAlignment = NSTextAlignment.center
    sender.setTitle("Some centered String", for:UIControlState.normal)
}

How to get a user's client IP address in ASP.NET?

If is c# see this way, is very simple

string clientIp = (Request.ServerVariables["HTTP_X_FORWARDED_FOR"] ?? 
                   Request.ServerVariables["REMOTE_ADDR"]).Split(',')[0].Trim();

Formatting DataBinder.Eval data

Why not use the simpler syntax?

<asp:Label id="lblNewsDate" runat="server" Text='<%# Eval("publishedDate", "{0:dddd d MMMM}") %>'</label>

This is the template control "Eval" that takes in the expression and the string format:

protected internal string Eval(
string expression,
string format

)

http://msdn.microsoft.com/en-us/library/3d2sz789.aspx

Why doesn't margin:auto center an image?

You need to render it as block level;

img {
   display: block;
   width: auto;
   margin: auto;
}

How to get selenium to wait for ajax response?

If using python, you may use this function, which clicks the button and waits for the DOM change:

def click_n_wait(driver, button, timeout=5):
    source = driver.page_source
    button.click()
    def compare_source(driver):
        try:
            return source != driver.page_source
        except WebDriverException:
            pass
    WebDriverWait(driver, timeout).until(compare_source)

(CREDIT: based on this stack overflow answer)

Joining pairs of elements of a list

Use an iterator.

List comprehension:

>>> si = iter(['abcd', 'e', 'fg', 'hijklmn', 'opq', 'r'])
>>> [c+next(si, '') for c in si]
['abcde', 'fghijklmn', 'opqr']

Very efficient for memory usage.
Exactly one traversal of s

Generator expression:

>>> si = iter(['abcd', 'e', 'fg', 'hijklmn', 'opq', 'r'])
>>> pair_iter = (c+next(si, '') for c in si)
>>> pair_iter # can be used in a for loop
<generator object at 0x4ccaa8>
>>> list(pair_iter) 
['abcde', 'fghijklmn', 'opqr']

use as an iterator

Using map, str.__add__, iter

>>> si = iter(['abcd', 'e', 'fg', 'hijklmn', 'opq', 'r'])
>>> map(str.__add__, si, si)
['abcde', 'fghijklmn', 'opqr']

next(iterator[, default]) is available starting in Python 2.6

NSDictionary to NSArray?

NSArray *keys = [dictionary allKeys];
NSArray *values = [dictionary allValues];

How to convert List to Json in Java

Try this:

public void test(){
// net.sf.json.JSONObject, net.sf.json.JSONArray    

List objList = new ArrayList();
objList.add("obj1");
objList.add("obj2");
objList.add("obj3");
HashMap objMap = new HashMap();
objMap.put("key1", "value1");
objMap.put("key2", "value2");
objMap.put("key3", "value3");
System.out.println("JSONArray :: "+(JSONArray)JSONSerializer.toJSON(objList));
System.out.println("JSONObject :: "+(JSONObject)JSONSerializer.toJSON(objMap));
}

you can find API here.

Changing Font Size For UITableView Section Headers

For iOS 7 I use this,


-(void)tableView:(UITableView *)tableView willDisplayHeaderView:(UIView *)view forSection:(NSInteger)section
{
    UITableViewHeaderFooterView *header = (UITableViewHeaderFooterView *)view;

    header.textLabel.font = [UIFont boldSystemFontOfSize:10.0f];
    header.textLabel.textColor = [UIColor orangeColor];
}

Here is Swift 3.0 version with header resizing

override func tableView(_ tableView: UITableView, willDisplayHeaderView view: UIView, forSection section: Int) {
    if let header = view as? UITableViewHeaderFooterView {
        header.textLabel!.font = UIFont.systemFont(ofSize: 24.0)
        header.textLabel!.textColor = UIColor.orange          
    }
}

Windows equivalent of OS X Keychain?

Credential dumping on Windows, even with "Credential Manager" is still an issue, and I don't think there is any way to prevent it outside of special hardware. MacOS keychain doesn't have this problem and so I don't think there is an exact equivalent.

Difference between getContext() , getApplicationContext() , getBaseContext() and "this"

The question "what the Context is" is one of the most difficult questions in the Android universe.

Context defines methods that access system resources, retrieve application's static assets, check permissions, perform UI manipulations and many more. In essence, Context is an example of God Object anti-pattern in production.

When it comes to which kind of Context should we use, it becomes very complicated because except for being God Object, the hierarchy tree of Context subclasses violates Liskov Substitution Principle brutally.

This blog post (now from Wayback Machine) attempts to summarize Context classes applicability in different situations.

Let me copy the main table from that post for completeness:

+----------------------------+-------------+----------+---------+-----------------+-------------------+
|                            | Application | Activity | Service | ContentProvider | BroadcastReceiver |
+----------------------------+-------------+----------+---------+-----------------+-------------------+
| Show a Dialog              | NO          | YES      | NO      | NO              | NO                |
| Start an Activity          | NO¹         | YES      | NO¹     | NO¹             | NO¹               |
| Layout Inflation           | NO²         | YES      | NO²     | NO²             | NO²               |
| Start a Service            | YES         | YES      | YES     | YES             | YES               |
| Bind to a Service          | YES         | YES      | YES     | YES             | NO                |
| Send a Broadcast           | YES         | YES      | YES     | YES             | YES               |
| Register BroadcastReceiver | YES         | YES      | YES     | YES             | NO³               |
| Load Resource Values       | YES         | YES      | YES     | YES             | YES               |
+----------------------------+-------------+----------+---------+-----------------+-------------------+

An application CAN start an Activity from here, but it requires that a new task be created. This may fit specific use cases, but can create non-standard back stack behaviors in your application and is generally not recommended or considered good practice.
This is legal, but inflation will be done with the default theme for the system on which you are running, not what’s defined in your application.
Allowed if the receiver is null, which is used for obtaining the current value of a sticky broadcast, on Android 4.2 and above.

screenshot

ERROR: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it

I had a similar issue when trying to migrate a Drupal website from one local host to another. From Mac running XAMMP to Windows running WAMP.

This was the error message I kept getting when trying to access the pages of the website.

PDOException: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it. 
in drupal_get_installed_schema_version() (line 155 of C:\wamp\www\chia\includes\install.inc).

In settings.php, I've changed everything correctly, database name, user and password.

$databases = array (
  'default' => 
  array (
    'default' => 
    array (
      'database' => 'mydatabasename',
      'username' => 'mydbusername',
      'password' => 'mydbpass',
      'host' => 'localhost',
      'port' => '8889',
      'driver' => 'mysql',
      'prefix' => '',
    ),
  ),
);

After a couple of hours of mindless google searching I've changed the port to a empty value:

'port' => '',

And after that the site loaded properly.

AngularJS passing data to $http.get request

Here's a complete example of an HTTP GET request with parameters using angular.js in ASP.NET MVC:

CONTROLLER:

public class AngularController : Controller
{
    public JsonResult GetFullName(string name, string surname)
    {
        System.Diagnostics.Debugger.Break();
        return Json(new { fullName = String.Format("{0} {1}",name,surname) }, JsonRequestBehavior.AllowGet);
    }
}

VIEW:

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.3.15/angular.min.js"></script>
<script type="text/javascript">
    var myApp = angular.module("app", []);

    myApp.controller('controller', function ($scope, $http) {

        $scope.GetFullName = function (employee) {

            //The url is as follows - ControllerName/ActionName?name=nameValue&surname=surnameValue

            $http.get("/Angular/GetFullName?name=" + $scope.name + "&surname=" + $scope.surname).
            success(function (data, status, headers, config) {
                alert('Your full name is - ' + data.fullName);
            }).
            error(function (data, status, headers, config) {
                alert("An error occurred during the AJAX request");
            });

        }
    });

</script>

<div ng-app="app" ng-controller="controller">

    <input type="text" ng-model="name" />
    <input type="text" ng-model="surname" />
    <input type="button" ng-click="GetFullName()" value="Get Full Name" />
</div>

Loop through an array php

foreach($array as $item=>$values){
     echo $values->filepath;
    }

How to write a std::string to a UTF-8 text file

If by "simple" you mean ASCII, there is no need to do any encoding, since characters with an ASCII value of 127 or less are the same in UTF-8.

Cannot read property 'addEventListener' of null

I had the same problem, but my id was present. So I tried adding "window.onload = init;" Then I wrapped my original JS code with an init function (call it what you want). This worked, so at least in my case, I was adding an event listener before my document loaded. This could be what you are experiencing as well.

anaconda/conda - install a specific package version

If any of these characters, '>', '<', '|' or '*', are used, a single or double quotes must be used

conda install [-y] package">=version"
conda install [-y] package'>=low_version, <=high_version'
conda install [-y] "package>=low_version, <high_version"

conda install -y torchvision">=0.3.0"
conda install  openpyxl'>=2.4.10,<=2.6.0'
conda install "openpyxl>=2.4.10,<3.0.0"

where option -y, --yes Do not ask for confirmation.

Here is a summary:

Format         Sample Specification     Results
Exact          qtconsole==4.5.1         4.5.1
Fuzzy          qtconsole=4.5            4.5.0, 4.5.1, ..., etc.
>=, >, <, <=  "qtconsole>=4.5"          4.5.0 or higher
               qtconsole"<4.6"          less than 4.6.0

OR            "qtconsole=4.5.1|4.5.2"   4.5.1, 4.5.2
AND           "qtconsole>=4.3.1,<4.6"   4.3.1 or higher but less than 4.6.0

Potion of the above information credit to Conda Cheat Sheet

Tested on conda 4.7.12

Load a Bootstrap popover content with AJAX. Is this possible?

Another solution:

$target.find('.myPopOver').mouseenter(function()
{
    if($(this).data('popover') == null)
    {
        $(this).popover({
            animation: false,
            placement: 'right',
            trigger: 'manual',
            title: 'My Dynamic PopOver',
            html : true,
            template: $('#popoverTemplate').clone().attr('id','').html()
        });
    }
    $(this).popover('show');
    $.ajax({
        type: HTTP_GET,
        url: "/myURL"

        success: function(data)
        {
            //Clean the popover previous content
            $('.popover.in .popover-inner').empty();    

            //Fill in content with new AJAX data
            $('.popover.in .popover-inner').html(data);

        }
    });

});

$target.find('.myPopOver').mouseleave(function()
{
    $(this).popover('hide');
});

The idea here is to trigger manually the display of PopOver with mouseenter & mouseleave events.

On mouseenter, if there is no PopOver created for your item (if($(this).data('popover') == null)), create it. What is interesting is that you can define your own PopOver content by passing it as argument (template) to the popover() function. Do not forget to set the html parameter to true also.

Here I just create a hidden template called popovertemplate and clone it with JQuery. Do not forget to delete the id attribute once you clone it otherwise you'll end up with duplicated ids in the DOM. Also notice that style="display: none" to hide the template in the page.

<div id="popoverTemplateContainer" style="display: none">

    <div id="popoverTemplate">
        <div class="popover" >
            <div class="arrow"></div>
            <div class="popover-inner">
                //Custom data here
            </div>
        </div>
    </div>
</div>

After the creation step (or if it has been already created), you just display the popOver with $(this).popover('show');

Then classical Ajax call. On success you need to clean the old popover content before putting new fresh data from server. How can we get the current popover content ? With the .popover.in selector! The .in class indicates that the popover is currently displayed, that's the trick here!

To finish, on mouseleave event, just hide the popover.

What does enumerate() mean?

The enumerate function works as follows:

doc = """I like movie. But I don't like the cast. The story is very nice"""
doc1 = doc.split('.')
for i in enumerate(doc1):
     print(i)

The output is

(0, 'I like movie')
(1, " But I don't like the cast")
(2, ' The story is very nice')

finding first day of the month in python

Use arrow.

import arrow
arrow.utcnow().span('month')[0]

Using "If cell contains #N/A" as a formula condition.

You can also use IFNA(expression, value)

generate random string for div id

I also needed a random id, I went with using base64 encoding:

btoa(Math.random()).substring(0,12)

Pick however many characters you want, the result is usually at least 24 characters.

How do I execute external program within C code in linux with arguments?

For a simple way, use system():

#include <stdlib.h>
...
int status = system("./foo 1 2 3");

system() will wait for foo to complete execution, then return a status variable which you can use to check e.g. exitcode (the command's exitcode gets multiplied by 256, so divide system()'s return value by that to get the actual exitcode: int exitcode = status / 256).

The manpage for wait() (in section 2, man 2 wait on your Linux system) lists the various macros you can use to examine the status, the most interesting ones would be WIFEXITED and WEXITSTATUS.

Alternatively, if you need to read foo's standard output, use popen(3), which returns a file pointer (FILE *); interacting with the command's standard input/output is then the same as reading from or writing to a file.

expected constructor, destructor, or type conversion before ‘(’ token

You are missing the std namespace reference in the cc file. You should also call nom.c_str() because there is no implicit conversion from std::string to const char * expected by ifstream's constructor.

Polygone::Polygone(std::string nom) {
    std::ifstream fichier (nom.c_str(), std::ifstream::in);
    // ...
}

How to print something when running Puppet client?

Have you tried what is on the sample. I am new to this but here is the command: puppet --test --trace --debug. I hope this helps.

Send Outlook Email Via Python?

For a solution that uses outlook see TheoretiCAL's answer below.

Otherwise, use the smtplib that comes with python. Note that this will require your email account allows smtp, which is not necessarily enabled by default.

SERVER = "smtp.example.com"
FROM = "[email protected]"
TO = ["listOfEmails"] # must be a list

SUBJECT = "Subject"
TEXT = "Your Text"

# Prepare actual message
message = """From: %s\r\nTo: %s\r\nSubject: %s\r\n\

%s
""" % (FROM, ", ".join(TO), SUBJECT, TEXT)

# Send the mail
import smtplib
server = smtplib.SMTP(SERVER)
server.sendmail(FROM, TO, message)
server.quit()

EDIT: this example uses reserved domains like described in RFC2606

SERVER = "smtp.example.com"
FROM = "[email protected]"
TO = ["[email protected]"] # must be a list

SUBJECT = "Hello!"
TEXT = "This is a test of emailing through smtp of example.com."

# Prepare actual message
message = """From: %s\r\nTo: %s\r\nSubject: %s\r\n\

%s
""" % (FROM, ", ".join(TO), SUBJECT, TEXT)

# Send the mail
import smtplib
server = smtplib.SMTP(SERVER)
server.login("MrDoe", "PASSWORD")
server.sendmail(FROM, TO, message)
server.quit()

_{For it to actually work with gmail, Mr. Doe will need to go to the options tab in gmail and set it to allow smtp connections.}

Note the addition of the login line to authenticate to the remote server. The original version does not include this, an oversight on my part.

Arrow operator (->) usage in C

struct Node {
    int i;
    int j;
};
struct Node a, *p = &a;

Here the to access the values of i and j we can use the variable a and the pointer p as follows: a.i, (*p).i and p->i are all the same.

Here . is a "Direct Selector" and -> is an "Indirect Selector".

How to run sql script using SQL Server Management Studio?

This website has a concise tutorial on how to use SQL Server Management Studio. As you will see you can open a "Query Window", paste your script and run it. It does not allow you to execute scripts by using the file path. However, you can do this easily by using the command line (cmd.exe):

sqlcmd -S .\SQLExpress -i SqlScript.sql

Where SqlScript.sql is the script file name located at the current directory. See this Microsoft page for more examples

How to quickly check if folder is empty (.NET)?

You could try Directory.Exists(path) and Directory.GetFiles(path) - probably less overhead (no objects - just strings etc).

What is "loose coupling?" Please provide examples

I propose a very simple Test of Code Coupling:

Piece A of code is tightly coupled to Piece B of code if there exists any possible modification to the Piece B that would force changes in Piece A in order to keep correctness.
Piece A of code is not tightly coupled to Piece B of code if there is no possible modification to the Piece B that would make a change to Piece A necessary.

This will help you to verify how much coupling there is between the pieces of your code. for reasoning on that see this blog post: http://marekdec.wordpress.com/2012/11/14/loose-coupling-tight-coupling-decoupling-what-is-that-all-about/

UTF-8 output from PowerShell

This is a bug in .NET. When PowerShell launches, it caches the output handle (Console.Out). The Encoding property of that text writer does not pick up the value StandardOutputEncoding property.

When you change it from within PowerShell, the Encoding property of the cached output writer returns the cached value, so the output is still encoded with the default encoding.

As a workaround, I would suggest not changing the encoding. It will be returned to you as a Unicode string, at which point you can manage the encoding yourself.

Caching example:

102 [C:\Users\leeholm]
>> $r1 = [Console]::Out

103 [C:\Users\leeholm]
>> $r1

Encoding                                          FormatProvider
--------                                          --------------
System.Text.SBCSCodePageEncoding                  en-US



104 [C:\Users\leeholm]
>> [Console]::OutputEncoding = [System.Text.Encoding]::UTF8

105 [C:\Users\leeholm]
>> $r1

Encoding                                          FormatProvider
--------                                          --------------
System.Text.SBCSCodePageEncoding                  en-US

Change the name of a key in dictionary

If you have a complex dict, it means there is a dict or list within the dict:

myDict = {1:"one",2:{3:"three",4:"four"}}
myDict[2][5] = myDict[2].pop(4)
print myDict

Output
{1: 'one', 2: {3: 'three', 5: 'four'}}

How can I create a simple message box in Python?

A recent message box version is the prompt_box module. It has two packages: alert and message. Message gives you greater control over the box, but takes longer to type up.

Example Alert code:

import prompt_box

prompt_box.alert('Hello') #This will output a dialog box with title Neutrino and the 
#text you inputted. The buttons will be Yes, No and Cancel

Example Message code:

import prompt_box

prompt_box.message('Hello', 'Neutrino', 'You pressed yes', 'You pressed no', 'You 
pressed cancel') #The first two are text and title, and the other three are what is 
#printed when you press a certain button

What is the IntelliJ shortcut key to create a javadoc comment?

Shortcut Alt+Enter shows intention actions where you can choose "Add Javadoc".

Rename all files in directory from $filename_h to $filename_half?

Although the answer set is complete, I need to add another missing one.

for i in *_h.png;
  do name=`echo "$i" | cut -d'_' -f1`
  echo "Executing of name $name" 
  mv "$i" "${name}_half.png"
done

How to validate an e-mail address in swift?

Here is an extension in Swift 3

extension String {
    func isValidEmail() -> Bool {
        let emailRegex = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
        return NSPredicate(format: "SELF MATCHES %@", emailRegex).evaluate(with: self)
    }
}

Just use it like this:

if yourEmailString.isValidEmail() {
    //code for valid email address
} else {
    //code for not valid email address
}

How to insert DECIMAL into MySQL database

MySql decimal types are a little bit more complicated than just left-of and right-of the decimal point.

The first argument is precision, which is the number of total digits. The second argument is scale which is the maximum number of digits to the right of the decimal point.

Thus, (4,2) can be anything from -99.99 to 99.99.

As for why you're getting 99.99 instead of the desired 3.80, the value you're inserting must be interpreted as larger than 99.99, so the max value is used. Maybe you could post the code that you are using to insert or update the table.

Edit

Corrected a misunderstanding of the usage of scale and precision, per http://dev.mysql.com/doc/refman/5.0/en/numeric-types.html.

how to install multiple versions of IE on the same system?

You can use IETester (http://www.my-debugbar.com/wiki/IETester/HomePage)

Warning: comparison with string literals results in unspecified behaviour

This an old question, but I have had to explain it to someone recently and I thought recording the answer here would be helpful at least in understanding how C works.

String literals like

"a"

"This is a string"

are put in the text or data segments of your program.

A string in C is actually a pointer to a char, and the string is understood to be the subsequent chars in memory up until a NUL char is encountered. That is, C doesn't really know about strings.

So if I have

char *s1 = "This is a string";

then s1 is a pointer to the first byte of the string.

Now, if I have

char *s2 = "This is a string";

this is also a pointer to the same first byte of that string in the text or data segment of the program.

But if I have

char *s3 = malloc( 17 );
strcpy(s3, "This is a string");

then s3 is a pointer to another place in memory into which I copy all the bytes of the other strings.

Illustrative examples:

Although, as your compiler rightly points out, you shouldn't do this, the following will evaluate to true:

s1 == s2 // True: we are comparing two pointers that contain the same address

but the following will evaluate to false

s1 == s3 // False: Comparing two pointers that don't hold the same address.

And although it might be tempting to have something like this:

struct Vehicle{
    char *type;
    // other stuff
}

if( type == "Car" )
   //blah1
else if( type == "Motorcycle )
   //blah2

You shouldn't do it because it's not something that is guarantied to work. Even if you know that type will always be set using a string literal.

I have tested it and it works. If I do

A.type = "Car";

then blah1 gets executed and similarly for "Motorcycle". And you'd be able to do things like

if( A.type == B.type )

but this is just terrible. I'm writing about it because I think it's interesting to know why it works, and it helps understand why you shouldn't do it.

Solutions:

In your case, what you want to do is use strcmp(a,b) == 0 to replace a == b

In the case of my example, you should use an enum.

enum type {CAR = 0, MOTORCYCLE = 1}

The preceding thing with string was useful because you could print the type, so you might have an array like this

char *types[] = {"Car", "Motorcycle"};

And now that I think about it, this is error prone since one must be careful to maintain the same order in the types array.

Therefore it might be better to do

char *getTypeString(int type)
{
    switch(type)
    case CAR: return "Car";
    case MOTORCYCLE: return "Motorcycle"
    default: return NULL;
}

Android Log.v(), Log.d(), Log.i(), Log.w(), Log.e() - When to use each one?

The different methods are indications of priority. As you've listed them, they're going from least to most important. I think how you specifically map them to debug logs in your code depends on the component or app you're working on, as well as how Android treats them on different build flavors (eng, userdebug, and user). I have done a fair amount of work in the native daemons in Android, and this is how I do it. It may not apply directly to your app, but there may be some common ground. If my explanation sounds vague, it's because some of this is more of an art than a science. My basic rule is to be as efficient as possible, ensure you can reasonably debug your component without killing the performance of the system, and always check for errors and log them.

V - Printouts of state at different intervals, or upon any events occurring which my component processes. Also possibly very detailed printouts of the payloads of messages/events that my component receives or sends.

D - Details of minor events that occur within my component, as well as payloads of messages/events that my component receives or sends.

I - The header of any messages/events that my component receives or sends, as well as any important pieces of the payload which are critical to my component's operation.

W - Anything that happens that is unusual or suspicious, but not necessarily an error.

E - Errors, meaning things that aren't supposed to happen when things are working as they should.

The biggest mistake I see people make is that they overuse things like V, D, and I, but never use W or E. If an error is, by definition, not supposed to happen, or should only happen very rarely, then it's extremely cheap for you to log a message when it occurs. On the other hand, if every time somebody presses a key you do a Log.i(), you're abusing the shared logging resource. Of course, use common sense and be careful with error logs for things outside of your control (like network errors), or those contained in tight loops.

Maybe Bad

Log.i("I am here");

Good

Log.e("I shouldn't be here");

With all this in mind, the closer your code gets to "production ready", the more you can restrict the base logging level for your code (you need V in alpha, D in beta, I in production, or possibly even W in production). You should run through some simple use cases and view the logs to ensure that you can still mostly understand what's happening as you apply more restrictive filtering. If you run with the filter below, you should still be able to tell what your app is doing, but maybe not get all the details.

logcat -v threadtime MyApp:I *:S

array of string with unknown size

I think you may be looking for the StringBuilder class. If not, then the generic List class in string form:

List<string> myStringList = new List<string();
myStringList.Add("Test 1");
myStringList.Add("Test 2");

Or, if you need to be absolutely sure that the strings remain in order:

Queue<string> myStringInOriginalOrder = new Queue<string();
myStringInOriginalOrder.Enqueue("Testing...");
myStringInOriginalOrder.Enqueue("1...");
myStringInOriginalOrder.Enqueue("2...");
myStringInOriginalOrder.Enqueue("3...");

Remember, with the List class, the order of the items is an implementation detail and you are not guaranteed that they will stay in the same order you put them in.

How to sum all column values in multi-dimensional array?

You can try this:

$c = array_map(function () {
      return array_sum(func_get_args());
     },$a, $b);

and finally:

print_r($c);

What do multiple arrow functions mean in javascript?

It might be not totally related, but since the question mentioned react uses case (and I keep bumping into this SO thread): There is one important aspect of the double arrow function which is not explicitly mentioned here. Only the 'first' arrow(function) gets named (and thus 'distinguishable' by the run-time), any following arrows are anonymous and from React point of view count as a 'new' object on every render.

Thus double arrow function will cause any PureComponent to rerender all the time.

Example

You have a parent component with a change handler as:

handleChange = task => event => { ... operations which uses both task and event... };

and with a render like:

{ tasks.map(task => <MyTask handleChange={this.handleChange(task)}/> }

handleChange then used on an input or click. And this all works and looks very nice. BUT it means that any change that will cause the parent to rerender (like a completely unrelated state change) will also re-render ALL of your MyTask as well even though they are PureComponents.

This can be alleviated many ways such as passing the 'outmost' arrow and the object you would feed it with or writing a custom shouldUpdate function or going back to basics such as writing named functions (and binding the this manually...)

Link to add to Google calendar

There is a comprehensive doc for google calendar and other calendar services: https://github.com/InteractionDesignFoundation/add-event-to-calendar-docs/blob/master/services/google.md

An example of working link: https://calendar.google.com/calendar/render?action=TEMPLATE&text=Bithday&dates=20201231T193000Z/20201231T223000Z&details=With%20clowns%20and%20stuff&location=North%20Pole

How to determine the IP address of a Solaris system

The following worked pretty well for me:

ping -s my_host_name

JavaFX FXML controller - constructor vs initialize method

In a few words: The constructor is called first, then any @FXML annotated fields are populated, then initialize() is called.

This means the constructor does not have access to @FXML fields referring to components defined in the .fxml file, while initialize() does have access to them.

Quoting from the Introduction to FXML:

[...] the controller can define an initialize() method, which will be called once on an implementing controller when the contents of its associated document have been completely loaded [...] This allows the implementing class to perform any necessary post-processing on the content.

Remove Item from ArrayList

 public void DeleteUserIMP(UserIMP useriamp) {
       synchronized (ListUserIMP) {
            if (ListUserIMP.isEmpty()) {
            System.out.println("user is empty");
        }  else {
            Iterator<UserIMP> it = ListUserIMP.iterator();
            while (it.hasNext()) {
                UserIMP user = it.next();
                if (useriamp.getMoblieNumber().equals(user.getMoblieNumber())) {
                    it.remove();
                    System.out.println("remove it");
                }
            }
            // ListUserIMP.remove(useriamp);

            System.out.println(" this user removed");
        }
        Constants.RESULT_FOR_REGISTRATION = Constants.MESSAGE_OK;
        // System.out.println("This user Deleted " + Constants.MESSAGE_OK);

    }
}

What does CultureInfo.InvariantCulture mean?

For things like numbers (decimal points, commas in amounts), they are usually preferred in the specific culture.

A appropriate way to do this would be set it at the culture level (for German) like this:

Thread.CurrentThread.CurrentCulture.NumberFormat = new CultureInfo("de").NumberFormat;

How should I use Outlook to send code snippets?

I came across this looking for a way to format things better in an email to a co-worker. I ended up discovering that if you copy from Visual Studio Code (FREE) it retains the formatting, highlighting and everything else. This editor works with everything and has modules for every programming language I've ever encountered.

Looks beautiful in the email.

How to show math equations in general github's markdown(not github's blog)

If just wanted to show math in the browser for yourself, you could try the Chrome extension GitHub with MathJax. It's quite convenient.

if variable contains

If you have a lot of these to check you might want to store a list of the mappings and just loop over that, instead of having a bunch of if/else statements. Something like:

var CODE_TO_LOCATION = {
  'ST1': 'stoke central',
  'ST2': 'stoke north',
  // ...
};

function getLocation(text) {
  for (var code in CODE_TO_LOCATION) {
    if (text.indexOf(code) != -1) {
      return CODE_TO_LOCATION[code];
    }
  }
  return null;
}

This way you can easily add more code/location mappings. And if you want to handle more than one location you could just build up an array of locations in the function instead of just returning the first one you find.

Can I use a min-height for table, tr or td?

It's not a nice solution but try it like this:

<table>
    <tr>
        <td>
            <div>Lorem</div>
        </td>
    </tr>
    <tr>
        <td>
            <div>Ipsum</div>
        </td>
    </tr>
</table>

and set the divs to the min-height:

div {
    min-height: 300px;
}

Hope this is what you want ...

Why doesn't Java support unsigned ints?

As soon as signed and unsigned ints are mixed in an expression things start to get messy and you probably will lose information. Restricting Java to signed ints only really clears things up. I’m glad I don’t have to worry about the whole signed/unsigned business, though I sometimes do miss the 8th bit in a byte.

Python socket connection timeout

If you are using Python2.6 or newer, it's convenient to use socket.create_connection

sock = socket.create_connection(address, timeout=10)
sock.settimeout(None)
fileobj = sock.makefile('rb', 0)

Task continuation on UI thread

With async you just do:

await Task.Run(() => do some stuff);
// continue doing stuff on the same context as before.
// while it is the default it is nice to be explicit about it with:
await Task.Run(() => do some stuff).ConfigureAwait(true);

However:

await Task.Run(() => do some stuff).ConfigureAwait(false);
// continue doing stuff on the same thread as the task finished on.

PHP check whether property exists in object or class

Just putting my 2 cents here.

Given the following class:

class Foo
{
  private $data;

  public function __construct(array $data)
  {
    $this->data = $data;
  }

  public function __get($name)
  {
    return $data[$name];
  }

  public function __isset($name)
  {
    return array_key_exists($name, $this->data);
  }
}

the following will happen:

$foo = new Foo(['key' => 'value', 'bar' => null]);

var_dump(property_exists($foo, 'key'));  // false
var_dump(isset($foo->key));  // true
var_dump(property_exists($foo, 'bar'));  // false
var_dump(isset($foo->bar));  // true, although $data['bar'] == null

Hope this will help anyone

collapse cell in jupyter notebook

There's also an improved version of Pan Yan suggestion. It adds the button that shows code cells back:

%%html
<style id=hide>div.input{display:none;}</style>
<button type="button" 
onclick="var myStyle = document.getElementById('hide').sheet;myStyle.insertRule('div.input{display:inherit !important;}', 0);">
Show inputs</button>

Or python:

# Run me to hide code cells

from IPython.core.display import display, HTML
display(HTML(r"""<style id=hide>div.input{display:none;}</style><button type="button"onclick="var myStyle = document.getElementById('hide').sheet;myStyle.insertRule('div.input{display:inherit !important;}', 0);">Show inputs</button>"""))

How do I find my host and username on mysql?

The default username is root. You can reset the root password if you do not know it: http://dev.mysql.com/doc/refman/5.0/en/resetting-permissions.html. You should not, however, use the root account from PHP, set up a limited permission user to do that: http://dev.mysql.com/doc/refman/5.1/en/adding-users.html

If MySql is running on the same computer as your webserver, you can just use "localhost" as the host

What is a Python egg?

Note: Egg packaging has been superseded by Wheel packaging.

Same concept as a .jar file in Java, it is a .zip file with some metadata files renamed .egg, for distributing code as bundles.

Specifically: The Internal Structure of Python Eggs

A "Python egg" is a logical structure embodying the release of a specific version of a Python project, comprising its code, resources, and metadata. There are multiple formats that can be used to physically encode a Python egg, and others can be developed. However, a key principle of Python eggs is that they should be discoverable and importable. That is, it should be possible for a Python application to easily and efficiently find out what eggs are present on a system, and to ensure that the desired eggs' contents are importable.

The .egg format is well-suited to distribution and the easy uninstallation or upgrades of code, since the project is essentially self-contained within a single directory or file, unmingled with any other projects' code or resources. It also makes it possible to have multiple versions of a project simultaneously installed, such that individual programs can select the versions they wish to use.

Shell - Write variable contents to a file

When you say "copy the contents of a variable", does that variable contain a file name, or does it contain a name of a file?

I'm assuming by your question that $var contains the contents you want to copy into the file:

$ echo "$var" > "$destdir"

This will echo the value of $var into a file called $destdir. Note the quotes. Very important to have "$var" enclosed in quotes. Also for "$destdir" if there's a space in the name. To append it:

$ echo "$var" >> "$destdir"

Interactive shell using Docker Compose

If the yml is called docker-compose.yml it can be launched with a simple $ docker-compose up. The corresponding attachment of a terminal can be simply (consider that the yml has specified a service called myservice):

$ docker-compose exec myservice sh

However, if you are using a different yml file name, such as docker-compose-mycompose.yml, it should be launched using $ docker-compose -f docker-compose-mycompose.yml up. To attach an interactive terminal you have to specify the yml file too, just like:

$ docker-compose -f docker-compose-mycompose.yml exec myservice sh

How to find a number in a string using JavaScript?

_x000D_

var regex = /\d+/g;_x000D_
var string = "you can enter maximum 500 choices";_x000D_
var matches = string.match(regex);  // creates array from matches_x000D_
_x000D_
document.write(matches);

_x000D_

References:

http://www.regular-expressions.info/javascript.html

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp

Dead simple example of using Multiprocessing Queue, Pool and Locking

Here is an example from my code (for threaded pool, but just change class name and you'll have process pool):

def execute_run(rp): 
   ... do something 

pool = ThreadPoolExecutor(6)
for mat in TESTED_MATERIAL:
    for en in TESTED_ENERGIES:
        for ecut in TESTED_E_CUT:
            rp = RunParams(
                simulations, DEST_DIR,
                PARTICLE, mat, 960, 0.125, ecut, en
            )
            pool.submit(execute_run, rp)
pool.join()

Basically:

pool = ThreadPoolExecutor(6) creates a pool for 6 threads
Then you have bunch of for's that add tasks to the pool
pool.submit(execute_run, rp) adds a task to pool, first arogument is a function called in in a thread/process, rest of the arguments are passed to the called function.
pool.join waits until all tasks are done.

How do I POST urlencoded form data with $http without jQuery?

you need to post plain javascript object, nothing else

           var request = $http({
                method: "post",
                url: "process.cfm",
                transformRequest: transformRequestAsFormPost,
                data: { id: 4, name: "Kim" }
            });

            request.success(
                function( data ) {
                    $scope.localData = data;
                }
            );

if you have php as back-end then you will need to do some more modification.. checkout this link for fixing php server side

How to put labels over geom_bar in R with ggplot2

Another solution is to use stat_count() when dealing with discrete variables (and stat_bin() with continuous ones).

ggplot(data = df, aes(x = x)) +
geom_bar(stat = "count") + 
stat_count(geom = "text", colour = "white", size = 3.5,
aes(label = ..count..),position=position_stack(vjust=0.5))

Second line in li starts under the bullet after CSS-reset

The li tag has a property called list-style-position. This makes your bullets inside or outside the list. On default, it’s set to inside. That makes your text wrap around it. If you set it to outside, the text of your li tags will be aligned.

The downside of that is that your bullets won't be aligned with the text outside the ul. If you want to align it with the other text you can use a margin.

ul li {
    /*
     * We want the bullets outside of the list,
     * so the text is aligned. Now the actual bullet
     * is outside of the list’s container
     */
    list-style-position: outside;

    /*
     * Because the bullet is outside of the list’s
     * container, indent the list entirely
     */
    margin-left: 1em;
}

Edit 15th of March, 2014 Seeing people are still coming in from Google, I felt like the original answer could use some improvement

Changed the code block to provide just the solution
Changed the indentation unit to em’s
Each property is applied to the ul element
Good comments :)

How to convert string to IP address and vice versa

Hexadecimal IP Address to String IP

#include <iostream>
#include <sstream>
using namespace std;

int main()
{
    uint32_t ip = 0x0AA40001;
    string ip_str="";
    int temp = 0;
    for (int i = 0; i < 8; i++){
        if (i % 2 == 0)
        {
            temp += ip & 15;
            ip = ip >> 4;
        }
        else
        {
            stringstream ss;
            temp += (ip & 15) * 16;
            ip = ip >> 4;
            ss << temp;
            ip_str = ss.str()+"." + ip_str;
            temp = 0;
        }
    }
    ip_str.pop_back();
    cout << ip_str;
}

Output:10.164.0.1

How do I put all required JAR files in a library folder inside the final JAR file with Maven?

The simplest and the most efficient way is to use an uber plugin like this:

          <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                </execution>
            </executions>
            <configuration>
                <finalName>uber-${project.artifactId}-${project.version}</finalName>
            </configuration>
        </plugin>

You will have de-normalized all in one JAR file.

What is the "right" way to iterate through an array in Ruby?

Trying to do the same thing consistently with arrays and hashes might just be a code smell, but, at the risk of my being branded as a codorous half-monkey-patcher, if you're looking for consistent behaviour, would this do the trick?:

class Hash
    def each_pairwise
        self.each { | x, y |
            yield [x, y]
        }
    end
end

class Array
    def each_pairwise
        self.each_with_index { | x, y |
            yield [y, x]
        }
    end
end

["a","b","c"].each_pairwise { |x,y|
    puts "#{x} => #{y}"
}

{"a" => "Aardvark","b" => "Bogle","c" => "Catastrophe"}.each_pairwise { |x,y|
    puts "#{x} => #{y}"
}

Python naming conventions for modules

nib is fine. If in doubt, refer to the Python style guide.

From PEP 8:

Package and Module Names Modules should have short, all-lowercase names. Underscores can be used in the module name if it improves readability. Python packages should also have short, all-lowercase names, although the use of underscores is discouraged.

Since module names are mapped to file names, and some file systems are case insensitive and truncate long names, it is important that module names be chosen to be fairly short -- this won't be a problem on Unix, but it may be a problem when the code is transported to older Mac or Windows versions, or DOS.

When an extension module written in C or C++ has an accompanying Python module that provides a higher level (e.g. more object oriented) interface, the C/C++ module has a leading underscore (e.g. _socket).

What is the difference between git clone and checkout?

checkout can be use for many case :

1st case : switch between branch in local repository For instance : git checkout exists_branch_to_switch

You can also create new branch and switch out in throught this case with -b

git checkout -b new_branch_to_switch

2nd case : restore file from x rev

git checkout rev file_to_restore ...

How can I get the concatenation of two lists in Python without modifying either one?

concatenated_list = list_1 + list_2

Prevent form submission on Enter key press

native js (fetch api)

_x000D_

document.onload = (() => {_x000D_
    alert('ok');_x000D_
    let keyListener = document.querySelector('#searchUser');_x000D_
    // _x000D_
    keyListener.addEventListener('keypress', (e) => {_x000D_
        if(e.keyCode === 13){_x000D_
            let username = e.target.value;_x000D_
            console.log(`username = ${username}`);_x000D_
            fetch(`https://api.github.com/users/${username}`,{_x000D_
                data: {_x000D_
                    client_id: 'xxx',_x000D_
                    client_secret: 'xxx'_x000D_
                }_x000D_
            })_x000D_
            .then((user)=>{_x000D_
                console.log(`user = ${user}`);_x000D_
            });_x000D_
            fetch(`https://api.github.com/users/${username}/repos`,{_x000D_
                data: {_x000D_
                    client_id: 'xxx',_x000D_
                    client_secret: 'xxx'_x000D_
                }_x000D_
            })_x000D_
            .then((repos)=>{_x000D_
                console.log(`repos = ${repos}`);_x000D_
                for (let i = 0; i < repos.length; i++) {_x000D_
                     console.log(`repos ${i}  = ${repos[i]}`);_x000D_
                }_x000D_
            });_x000D_
        }else{_x000D_
            console.log(`e.keyCode = ${e.keyCode}`);_x000D_
        }_x000D_
    });_x000D_
})();

_x000D_

<input _ngcontent-inf-0="" class="form-control" id="searchUser" placeholder="Github username..." type="text">

_x000D_

Get current time in seconds since the Epoch on Linux, Bash

This is an extension to what @pellucide has done, but for Macs:

To determine the number of seconds since epoch (Jan 1 1970) for any given date (e.g. Oct 21 1973)

$ date -j -f "%b %d %Y %T" "Oct 21 1973 00:00:00" "+%s"
120034800

Please note, that for completeness, I have added the time part to the format. The reason being is that date will take whatever date part you gave it and add the current time to the value provided. For example, if you execute the above command at 4:19PM, without the '00:00:00' part, it will add the time automatically. Such that "Oct 21 1973" will be parsed as "Oct 21 1973 16:19:00". That may not be what you want.

To convert your timestamp back to a date:

$ date -j -r 120034800
Sun Oct 21 00:00:00 PDT 1973

Apple's man page for the date implementation: https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man1/date.1.html

Python Script to convert Image into Byte array

Use bytearray:

with open("img.png", "rb") as image:
  f = image.read()
  b = bytearray(f)
  print b[0]

You can also have a look at struct which can do many conversions of that kind.

PDOException “could not find driver” in php

How to check existence of user-define table type in SQL Server 2008?

IF EXISTS (SELECT * FROM sys.types WHERE is_table_type = 1 AND name = 'MyType')
    --stuff

sys.types... they aren't schema-scoped objects so won't be in sys.objects

Update, Mar 2013

You can use TYPE_ID too

How do you say not equal to in Ruby?

Yes. In Ruby the not equal to operator is:

!=

You can get a full list of ruby operators here: https://www.tutorialspoint.com/ruby/ruby_operators.htm.

How can I tell jackson to ignore a property for which I don't have control over the source code?

One more good point here is to use @JsonFilter. Some details here http://wiki.fasterxml.com/JacksonFeatureJsonFilter

Running conda with proxy

The best way I settled with is to set proxy environment variables right before using conda or pip install/update commands. Simply run:

set HTTP_PROXY=http://username:password@proxy_url:port

For example, your actual command could be like

set HTTP_PROXY=http://yourname:[email protected]_company.com:8080

If your company uses https proxy, then also

set HTTPS_PROXY=https://username:password@proxy_url:port

Once you exit Anaconda prompt then this setting is gone, so your username/password won't be saved after the session.

I didn't choose other methods mentioned in Anaconda documentation or some other sources, because they all require hardcoding of username/password into

Windows environment variables (also this requires restart of Anaconda prompt for the first time)
Conda .condarc or .netrc configuration files (also this won't work for PIP)
A batch/script file loaded while starting Anaconda prompt (also this might require configuring the path)

All of these are unsafe and will require constant update later. And if you forget where to update? More troubleshooting will come your way...

if statements matching multiple values

A more complicated way :) that emulates SQL's 'IN':

public static class Ext {    
    public static bool In<T>(this T t,params T[] values){
        foreach (T value in values) {
            if (t.Equals(value)) {
                return true;
            }
        }
        return false;
    }
}

if (value.In(1,2)) {
    // ...
}

But go for the standard way, it's more readable.

EDIT: a better solution, according to @Kobi's suggestion:

public static class Ext {    
    public static bool In<T>(this T t,params T[] values){
        return values.Contains(t);
    }
}

How do I prevent an Android device from going to sleep programmatically?

If you are a Xamarin user, this is the solution:

   protected override void OnCreate(Bundle bundle)
    {
        base.OnCreate(bundle); //always call superclass first

        this.Window.AddFlags(WindowManagerFlags.KeepScreenOn);

        LoadApplication(new App());
    }

How to check if a python module exists without importing it

Use one of the functions from pkgutil, for example:

from pkgutil import iter_modules

def module_exists(module_name):
    return module_name in (name for loader, name, ispkg in iter_modules())

SELECT using 'CASE' in SQL

This is just the syntax of the case statement, it looks like this.

SELECT 
  CASE 
    WHEN FRUIT = 'A' THEN 'APPLE' 
    WHEN FRUIT = 'B' THEN 'BANANA'     
  END AS FRUIT
FROM FRUIT_TABLE;

As a reminder remember; no assignment is performed the value becomes the column contents. (If you wanted to assign that to a variable you would put it before the CASE statement).

How do I find out what is hammering my SQL Server?

I assume due diligence here that you confirmed the CPU is actually consumed by SQL process (perfmon Process category counters would confirm this). Normally for such cases you take a sample of the relevant performance counters and you compare them with a baseline that you established in normal load operating conditions. Once you resolve this problem I recommend you do establish such a baseline for future comparisons.

You can find exactly where is SQL spending every single CPU cycle. But knowing where to look takes a lot of know how and experience. Is is SQL 2005/2008 or 2000 ? Fortunately for 2005 and newer there are a couple of off the shelf solutions. You already got a couple good pointer here with John Samson's answer. I'd like to add a recommendation to download and install the SQL Server Performance Dashboard Reports. Some of those reports include top queries by time or by I/O, most used data files and so on and you can quickly get a feel where the problem is. The output is both numerical and graphical so it is more usefull for a beginner.

I would also recommend using Adam's Who is Active script, although that is a bit more advanced.

And last but not least I recommend you download and read the MS SQL Customer Advisory Team white paper on performance analysis: SQL 2005 Waits and Queues.

My recommendation is also to look at I/O. If you added a load to the server that trashes the buffer pool (ie. it needs so much data that it evicts the cached data pages from memory) the result would be a significant increase in CPU (sounds surprising, but is true). The culprit is usually a new query that scans a big table end-to-end.

Installing SciPy and NumPy using pip

in my case, upgrading pip did the trick. Also, I've installed scipy with -U parameter (upgrade all packages to the last available version)

JSONObject - How to get a value?

If it's a deeper key/value you're after and you're not dealing with arrays of keys/values at each level, you could recursively search the tree:

public static String recurseKeys(JSONObject jObj, String findKey) throws JSONException {
    String finalValue = "";
    if (jObj == null) {
        return "";
    }

    Iterator<String> keyItr = jObj.keys();
    Map<String, String> map = new HashMap<>();

    while(keyItr.hasNext()) {
        String key = keyItr.next();
        map.put(key, jObj.getString(key));
    }

    for (Map.Entry<String, String> e : (map).entrySet()) {
        String key = e.getKey();
        if (key.equalsIgnoreCase(findKey)) {
            return jObj.getString(key);
        }

        // read value
        Object value = jObj.get(key);

        if (value instanceof JSONObject) {
            finalValue = recurseKeys((JSONObject)value, findKey);
        }
    }

    // key is not found
    return finalValue;
}

Usage:

JSONObject jObj = new JSONObject(jsonString);
String extract = recurseKeys(jObj, "extract");

Using Map code from https://stackoverflow.com/a/4149555/2301224

jquery find element by specific class when element has multiple classes

you are looking for http://api.jquery.com/hasClass/

<div id="mydiv" class="foo bar"></div>

$('#mydiv').hasClass('foo') //returns ture

How to fully clean bin and obj folders within Visual Studio?

Clean will remove all intermediate and final files created by the build process, such as .obj files and .exe or .dll files.

It does not, however, remove the directories where those files get built. I don't see a compelling reason why you need the directories to be removed. Can you explain further?

If you look inside these directories before and after a "Clean", you should see your compiled output get cleaned up.

How to enable C# 6.0 feature in Visual Studio 2013?

Under VS2013 you can install the new compilers into the project as a nuget package. That way you don't need VS2015 or an updated build server.

https://www.nuget.org/packages/Microsoft.Net.Compilers/

Install-Package Microsoft.Net.Compilers

The package allows you to use/build C# 6.0 code/syntax. Because VS2013 doesn't natively recognize the new C# 6.0 syntax, it will show errors in the code editor window although it will build fine.

Using Resharper, you'll get squiggly lines on C# 6 features, but the bulb gives you the option to 'Enable C# 6.0 support for this project' (setting saved to .DotSettings).

As mentioned by @stimpy77: for support in MVC Razor views you'll need an extra package (for those that don't read the comments)

Install-Package Microsoft.CodeDom.Providers.DotNetCompilerPlatform

If you want full C# 6.0 support, you'll need to install VS2015.

CSS animation delay in repeating

You can create a "fake" delay between infinite animations purely with CSS. The way to do it is smartly define your keyframe animation points and your animation duration speed.

For example, if we wanted to animate a bouncing ball, and we wanted a good .5s to 1s delay between each bounce, we can do something like:

@keyframes bounce{
    0%{
        transform: translateY(0);
    }
    50%{
        transform: translateY(25%);
    }
    75%{
        transform: translateY(15%);
    }
    90%{
        transform: translateY(0%);
    }
    100%{
        transform: translateY(0);
    }
}

What we do is make sure that the ball goes back to its original position much earlier than 100%. In my example, I'm doing it in 90% which provided me with around .1s delay which was good enough for me. But obviously for your case, you can either add more key frame points and change the transform values.

Furthermore, you can add additional animation duration to balance your key frame animations.

For example:

 animation: bounce .5s ease-in-out infinite;

Lets say that we wanted the full animation to end in .5s, but we wanted an additional .2s in delay between the animations.

 animation: bounce .7s ease-in-out infinite;

So we'll add an additional .2s delay, and in our key frame animations, we can add more percentage points to fill in the gaps of the .2s delay.

Chrome says "Resource interpreted as script but transferred with MIME type text/plain.", what gives?

The answer posted here by simon-sarris helped me.

This helped me solve my issue.

The Visual Studio installer must have added an errant line to the registry.

open up regedit and take a look at this registry key:

See that key? The Content Type key? change its value from text/plain to text/javascript.

Finally chrome can breathe easy again.

I should note that neither Content Type nor PercievedType are there by default on Windows 7, so you could probably safely delete them both, but the minimum you need to do is that edit.

Anyway I hope this fixes it for you too!

Don't forget to restart your system after the changes.

Symfony 2 EntityManager injection in service

Since 2017 and Symfony 3.3 you can register Repository as service, with all its advantages it has.

Check my post How to use Repository with Doctrine as Service in Symfony for more general description.

To your specific case, original code with tuning would look like this:

1. Use in your services or Controller

<?php

namespace Test\CommonBundle\Services;

use Doctrine\ORM\EntityManagerInterface;

class UserService
{
    private $userRepository;

    // use custom repository over direct use of EntityManager
    // see step 2
    public function __constructor(UserRepository $userRepository)
    {
        $this->userRepository = $userRepository;
    }

    public function getUser($userId)
    {
        return $this->userRepository->find($userId);
    }
}

2. Create new custom repository

<?php

namespace Test\CommonBundle\Repository;

use Doctrine\ORM\EntityManagerInterface;

class UserRepository
{
    private $repository;

    public function __construct(EntityManagerInterface $entityManager)
    {
        $this->repository = $entityManager->getRepository(UserEntity::class);
    }

    public function find($userId)
    {
        return  $this->repository->find($userId);
    }
}

3. Register services

# app/config/services.yml
services:
    _defaults:
        autowire: true

    Test\CommonBundle\:
       resource: ../../Test/CommonBundle

Installing PDO driver on MySQL Linux server

That's a good question, but I think you just misunderstand what you read.

Install PDO

The ./config --with-pdo-mysql is something you have to put on only if you compile your own PHP code. If you install it with package managers, you just have to use the command line given by Jany Hartikainen: sudo apt-get install php5-mysql and also sudo apt-get install pdo-mysql

Compatibility with mysql_

Apart from the fact mysql_ is really discouraged, they are both independent. If you use PDO mysql_ is not implicated, and if you use mysql_ PDO is not required.

If you turn off PDO without changing any line in your code, you won't have a problem. But since you started to connect and write queries with PDO, you have to keep it and give up mysql_.

Several years ago the MySQL team published a script to migrate to MySQLi. I don't know if it can be customised, but it's official.

"column not allowed here" error in INSERT statement

This error creeps in if we make some spelling mistake in entering the variable name. Like in stored proc, I have the variable name x and in my insert statement I am using

insert into tablename values(y);

It will throw an error column not allowed here.

What is the difference between exit and return?

the return statement exits from the current function and exit() exits from the program

they are the same when used in main() function

also return is a statement while exit() is a function which requires stdlb.h header file

How to take backup of a single table in a MySQL database?

You can use the below code:

For Single Table Structure alone Backup

mysqldump -d <database name> <tablename> > <filename.sql>

For Single Table Structure with data

mysqldump <database name> <tablename> > <filename.sql>

Hope it will help.

Where is adb.exe in windows 10 located?

Since you already have Android Studio installed, and require the environment variable ANDROID_HOME to be set, the easy way to do this is to add %ANDROID_HOME%\platform-tools to your path.

How to decompile a whole Jar file?

2009: JavaDecompiler can do a good job with a jar: since 0.2.5, All files, in JAR files, are displayed.

The JD-Eclipse doesn't seem to have changed since late 2009 though (see Changes).
So its integration with latest Eclipse (3.8, 4.2+) might be problematic.

JD-Core is actively maintained.

Both are the result of the fantastic work of (SO user) Emmanuel Dupuy.

2018: A more modern option, mentioned in the comments by David Kennedy Araujo:

JetBrains/intellij-community/plugins/java-decompiler/engine

Fernflower is the first actually working analytical decompiler for Java and probably for a high-level programming language in general.
java -jar fernflower.jar [-<option>=<value>]* [<source>]+ <destination>

java -jar fernflower.jar -hes=0 -hdc=0 c:\Temp\binary\ -e=c:\Java\rt.jar c:\Temp\source\

See also How to decompile to java files intellij idea for a command working with recent IntelliJ IDEA.

Limit String Length

$value = str_limit('This string is really really long.', 7);

// This st...

Python pandas: fill a dataframe row by row

If your input rows are lists rather than dictionaries, then the following is a simple solution:

import pandas as pd
list_of_lists = []
list_of_lists.append([1,2,3])
list_of_lists.append([4,5,6])

pd.DataFrame(list_of_lists, columns=['A', 'B', 'C'])
#    A  B  C
# 0  1  2  3
# 1  4  5  6

ip address validation in python using regex

The following will check whether an IP is valid or not: If the IP is within 0.0.0.0 to 255.255.255.255, then the output will be true, otherwise it will be false:

[0<=int(x)<256 for x in re.split('\.',re.match(r'^\d+\.\d+\.\d+\.\d+$',your_ip).group(0))].count(True)==4

Example:

your_ip = "10.10.10.10"
[0<=int(x)<256 for x in re.split('\.',re.match(r'^\d+\.\d+\.\d+\.\d+$',your_ip).group(0))].count(True)==4

Output:

>>> your_ip = "10.10.10.10"
>>> [0<=int(x)<256 for x in re.split('\.',re.match(r'^\d+\.\d+\.\d+\.\d+$',your_ip).group(0))].count(True)==4
True
>>> your_ip = "10.10.10.256"
>>> [0<=int(x)<256 for x in re.split('\.',re.match(r'^\d+\.\d+\.\d+\.\d+$',your_ip).group(0))].count(True)==4
False
>>>

How to get values and keys from HashMap?

You give 1 Dollar, it gives you a cheese burger. You give the String and it gives you the Tab. Use the GET method of HashMap to get what you want.

HashMap.get("String");

keypress, ctrl+c (or some combo like that)

I couldn't get it to work with .keypress(), but it worked with the .keydown() function like this:

$(document).keydown(function(e) {
    if(e.key == "c" && e.ctrlKey) {
        console.log('ctrl+c was pressed');
    }
});

How to compare two double values in Java?

        int mid = 10;
        for (double j = 2 * mid; j >= 0; j = j - 0.1) {
            if (j == mid) {
                System.out.println("Never happens"); // is NOT printed
            }

            if (Double.compare(j, mid) == 0) {
                System.out.println("No way!"); // is NOT printed
            }

            if (Math.abs(j - mid) < 1e-6) {
                System.out.println("Ha!"); // printed
            }
        }
        System.out.println("Gotcha!");

How to suspend/resume a process in Windows?

PsSuspend command line utility from SysInternals suite. It suspends / resumes a process by its id.

Popup window in winform c#

Forms in C# are classes that inherit the Form base class.

You can show a popup by creating an instance of the class and calling ShowDialog().

Removing certain characters from a string in R

try: gsub('\\$', '', '$5.00$')

Difference between ProcessBuilder and Runtime.exec()

There are no difference between ProcessBuilder.start() and Runtime.exec() because implementation of Runtime.exec() is:

public Process exec(String command) throws IOException {
    return exec(command, null, null);
}

public Process exec(String command, String[] envp, File dir)
    throws IOException {
    if (command.length() == 0)
        throw new IllegalArgumentException("Empty command");

    StringTokenizer st = new StringTokenizer(command);
    String[] cmdarray = new String[st.countTokens()];
    for (int i = 0; st.hasMoreTokens(); i++)
        cmdarray[i] = st.nextToken();
    return exec(cmdarray, envp, dir);
}

public Process exec(String[] cmdarray, String[] envp, File dir)
    throws IOException {
    return new ProcessBuilder(cmdarray)
        .environment(envp)
        .directory(dir)
        .start();
}

So code:

List<String> list = new ArrayList<>();
new StringTokenizer(command)
.asIterator()
.forEachRemaining(str -> list.add((String) str));
new ProcessBuilder(String[])list.toArray())
            .environment(envp)
            .directory(dir)
            .start();

should be the same as:

Runtime.exec(command)

Thanks dave_thompson_085 for comment

How to change a package name in Eclipse?

create a new package, drag and drop the class into it and now you are able to rename the new package

sudo service mongodb restart gives "unrecognized service error" in ubuntu 14.0.4

For debian, from the 10gen repo, between 2.4.x and 2.6.x, they renamed the init script /etc/init.d/mongodb to /etc/init.d/mongod, and the default config file from /etc/mongodb.conf to /etc/mongod.conf, and the PID and lock files from "mongodb" to "mongod" too. This made upgrading a pain, and I don't see it mentioned in their docs anywhere. Anyway, the solution is to remove the old "mongodb" versions:

update-rc.d -f mongodb remove
rm /etc/init.d/mongodb
rm /var/run/mongodb.pid
diff -ur /etc/mongodb.conf /etc/mongod.conf

Now, look and see what config changes you need to keep, and put them in mongod.conf.

Then:

rm /etc/mongodb.conf

Now you can:

service mongod restart

How to find index of STRING array in Java from a given value?

Try this Function :

public int indexOfArray(String input){
     for(int i=0;i<TYPES,length();i++)
       {
         if(TYPES[i].equals(input))
         {
          return i ;
         }
        }
      return -1     // if the text not found the function return -1
      }

MySQL - count total number of rows in php

mysqli_num_rows is used in php 5 and above.

e.g

<?php
$con=mysqli_connect("localhost","my_user","my_password","my_db");
// Check connection
if (mysqli_connect_errno())
  {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
  }

$sql="SELECT Lastname,Age FROM Persons ORDER BY Lastname";

if ($result=mysqli_query($con,$sql))
  {
  // Return the number of rows in result set
  $rowcount=mysqli_num_rows($result);
  printf("Result set has %d rows.\n",$rowcount);
  // Free result set
  mysqli_free_result($result);
  }
mysqli_close($con);
?>

Resize a picture to fit a JLabel

Outline

Here are the steps to follow.

Read the picture as a BufferedImage.
Resize the BufferedImage to another BufferedImage that's the size of the JLabel.
Create an ImageIcon from the resized BufferedImage.

You do not have to set the preferred size of the JLabel. Once you've scaled the image to the size you want, the JLabel will take the size of the ImageIcon.

Read the picture as a BufferedImage

BufferedImage img = null;
try {
    img = ImageIO.read(new File("strawberry.jpg"));
} catch (IOException e) {
    e.printStackTrace();
}

Resize the BufferedImage

Image dimg = img.getScaledInstance(label.getWidth(), label.getHeight(),
        Image.SCALE_SMOOTH);

Make sure that the label width and height are the same proportions as the original image width and height. In other words, if the picture is 600 x 900 pixels, scale to 100 X 150. Otherwise, your picture will be distorted.

Create an ImageIcon

ImageIcon imageIcon = new ImageIcon(dimg);

converting numbers in to words C#

When I had to solve this problem, I created a hard-coded data dictionary to map between numbers and their associated words. For example, the following might represent a few entries in the dictionary:

{1, "one"}
{2, "two"}
{30, "thirty"}

You really only need to worry about mapping numbers in the 10^0 (1,2,3, etc.) and 10^1 (10,20,30) positions because once you get to 100, you simply have to know when to use words like hundred, thousand, million, etc. in combination with your map. For example, when you have a number like 3,240,123, you get: three million two hundred forty thousand one hundred twenty three.

After you build your map, you need to work through each digit in your number and figure out the appropriate nomenclature to go with it.

Uses for the '"' entity in HTML

Reason #1

There was a point where buggy/lazy implementations of HTML/XHTML renderers were more common than those that got it right. Many years ago, I regularly encountered rendering problems in mainstream browsers resulting from the use of unencoded quote chars in regular text content of HTML/XHTML documents. Though the HTML spec has never disallowed use of these chars in text content, it became fairly standard practice to encode them anyway, so that non-spec-compliant browsers and other processors would handle them more gracefully. As a result, many "old-timers" may still do this reflexively. It is not incorrect, though it is now probably unnecessary, unless you're targeting some very archaic platforms.

Reason #2

When HTML content is generated dynamically, for example, by populating an HTML template with simple string values from a database, it's necessary to encode each value before embedding it in the generated content. Some common server-side languages provided a single function for this purpose, which simply encoded all chars that might be invalid in some context within an HTML document. Notably, PHP's htmlspecialchars() function is one such example. Though there are optional arguments to htmlspecialchars() that will cause it to ignore quotes, those arguments were (and are) rarely used by authors of basic template-driven systems. The result is that all "special chars" are encoded everywhere they occur in the generated HTML, without regard for the context in which they occur. Again, this is not incorrect, it's simply unnecessary.

Node update a specific package

Use npm outdated to see Current and Latest version of all packages.

Then npm i packageName@versionNumber to install specific version : example npm i [email protected].

Or npm i packageName@latest to install latest version : example npm i browser-sync@latest.

The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication

In my case the reason was some wrong certificate that could not be loaded. I found out about it from the Event Viewer, under System:

A fatal error occurred when attempting to access the TLS server credential private key. The error code returned from the cryptographic module is 0x8009030D. The internal error state is 10001.

JavaScript onclick redirect

Doing this fixed my issue

<script type="text/javascript">
    function SubmitFrm(){
        var Searchtxt = document.getElementById("txtSearch").value;
        window.location = "http://www.mysite.com/search/?Query=" + Searchtxt;
    }
</script>

I changed .value(); to .value; taking out the ()

I did not change anything in my text field or submit button

<input name="txtSearch" type="text" id="txtSearch" class="field" />            
<input type="submit" name="btnSearch" value="" id="btnSearch" class="btn" onclick="javascript:SubmitFrm()" />

Works like a charm.

How to have comments in IntelliSense for function in Visual Studio?

What you need is xml comments - basically, they follow this syntax (as vaguely described by Solmead):

///<summary>
///This is a description of my function.
///</summary>
string myFunction() {
     return "blah";
}

'''<summary>
'''This is a description of my function.
'''</summary>
Function myFunction() As String
    Return "blah"
End Function

#1227 - Access denied; you need (at least one of) the SUPER privilege(s) for this operation

In my case there was no DEFINER or root@localhost mentioned in my SQL file. Actually I was trying to import and run SQL file into SQLYog from Database->Import->Execute SQL Script menu. That was giving error.

Then I copied all the script from SQL file and ran in SQLYog query editor. That worked perfectly fine.

Git merge reports "Already up-to-date" though there is a difference

If merging branch A into branch B reports "Already up to date", reverse is not always true. It is true only if branch B is descendant of branch A, otherwise branch B simply can have changes that aren't in A.

Example:

You create branches A and B off master
You make some changes in master and merge these changes only into branch B (not updating or forgetting to update branch A).
You make some changes in branch A and merge A to B.

At this point merging A to B reports "Already up to date" but the branches are different because branch B has updates from master while branch A does not.

What is "Advanced" SQL?

Performance tuning, creating indices, stored procedures, etc.

"Advanced" means something different to everyone. I'd imagine this type of thing means something different to every job-poster.

OpenSSL and error in reading openssl.conf file

Just try to run openssl.exe as administrator.

#1025 - Error on rename of './database/#sql-2e0f_1254ba7' to './database/table' (errno: 150)

As was said you need to remove the FKs before. On Mysql do it like this:

ALTER TABLE `table_name` DROP FOREIGN KEY `id_name_fk`;

ALTER TABLE `table_name` DROP INDEX `id_name_fk`;

Where to get this Java.exe file for a SQL Developer installation

Use any JDK installation as long as it is NOT 64bit. The easiest way to find out if it is 64bit installation is to check the folder it resides into. e.g.

C:\Program Files\... is for 64 bit programs
C:\Program Files (x86)\... is for 32 bit programs

Commenting multiple lines in DOS batch file

Just want to mention that pdub's GOTO solution is not fully correct in case :comment label appear in multiple times. I modify the code from this question as the example.

@ECHO OFF
SET FLAG=1
IF [%FLAG%]==[1] (
    ECHO IN THE FIRST IF...
    GOTO comment
    ECHO "COMMENT PART 1"
:comment
    ECHO HERE AT TD_NEXT IN THE FIRST BLOCK
)

IF [%FLAG%]==[1] (
    ECHO IN THE SECOND IF...
    GOTO comment
    ECHO "COMMENT PART"
:comment
    ECHO HERE AT TD_NEXT IN THE SECOND BLOCK
)

The output will be

IN THE FIRST IF...
HERE AT TD_NEXT IN THE SECOND BLOCK

The command ECHO HERE AT TD_NEXT IN THE FIRST BLOCK is skipped.

Get the current date in java.sql.Date format

These are all too long.

Just use:

new Date(System.currentTimeMillis())

500 Internal Server Error for php file not for html

I was having this problem because I was trying to connect to MySQL but I didn't have the required package. I figured it out because of @Amadan's comment to check the error log. In my case, I was having the error: Call to undefined function mysql_connect()

If your PHP file has any code to connect with a My-SQL db then you might need to install php5-mysql first. I was getting this error because I hadn't installed it. All my file permissions were good. In Ubuntu, you can install it by the following command:

sudo apt-get install php5-mysql

How to copy a file to a remote server in Python using SCP or SSH?

There are a couple of different ways to approach the problem:

Wrap command-line programs
use a Python library that provides SSH capabilities (eg - Paramiko or Twisted Conch)

Each approach has its own quirks. You will need to setup SSH keys to enable password-less logins if you are wrapping system commands like "ssh", "scp" or "rsync." You can embed a password in a script using Paramiko or some other library, but you might find the lack of documentation frustrating, especially if you are not familiar with the basics of the SSH connection (eg - key exchanges, agents, etc). It probably goes without saying that SSH keys are almost always a better idea than passwords for this sort of stuff.

NOTE: its hard to beat rsync if you plan on transferring files via SSH, especially if the alternative is plain old scp.

I've used Paramiko with an eye towards replacing system calls but found myself drawn back to the wrapped commands due to their ease of use and immediate familiarity. You might be different. I gave Conch the once-over some time ago but it didn't appeal to me.

If opting for the system-call path, Python offers an array of options such as os.system or the commands/subprocess modules. I'd go with the subprocess module if using version 2.4+.

How do I populate a JComboBox with an ArrayList?

DefaultComboBoxModel dml= new DefaultComboBoxModel();
for (int i = 0; i < <ArrayList>.size(); i++) {
  dml.addElement(<ArrayList>.get(i).getField());
}

<ComboBoxName>.setModel(dml);

Understandable code.Edit<> with type as required.

Angular directive how to add an attribute to the element?

You can try this:

<div ng-app="app">
    <div ng-controller="AppCtrl">
        <a my-dir ng-repeat="user in users" ng-click="fxn()">{{user.name}}</a>
    </div>
</div>

<script>
var app = angular.module('app', []);

function AppCtrl($scope) {
        $scope.users = [{ name: 'John', id: 1 }, { name: 'anonymous' }];
        $scope.fxn = function () {
            alert('It works');
        };
    }

app.directive("myDir", function ($compile) {
    return {
        scope: {ngClick: '='}
    };
});
</script>

QByteArray to QString

you can use QString::fromAscii()

QByteArray data = entity->getData();
QString s_data = QString::fromAscii(data.data());

with data() returning a char*

for QT5, you should use fromCString() instead, as fromAscii() is deprecated, see ~~https://bugreports.qt-project.org/browse/QTBUG-21872~~ https://bugreports.qt.io/browse/QTBUG-21872

SignalR - Sending a message to a specific user using (IUserIdProvider) NEW 2.0.0

For anyone trying to do this in asp.net core. You can use claims.

public class CustomEmailProvider : IUserIdProvider
{
    public virtual string GetUserId(HubConnectionContext connection)
    {
        return connection.User?.FindFirst(ClaimTypes.Email)?.Value;
    }
}

Any identifier can be used, but it must be unique. If you use a name identifier for example, it means if there are multiple users with the same name as the recipient, the message would be delivered to them as well. I have chosen email because it is unique to every user.

Then register the service in the startup class.

services.AddSingleton<IUserIdProvider, CustomEmailProvider>();

Next. Add the claims during user registration.

var result = await _userManager.CreateAsync(user, Model.Password);
if (result.Succeeded)
{
    await _userManager.AddClaimAsync(user, new Claim(ClaimTypes.Email, Model.Email));
}

To send message to the specific user.

public class ChatHub : Hub
{
    public async Task SendMessage(string receiver, string message)
    {
        await Clients.User(receiver).SendAsync("ReceiveMessage", message);
    }
}

Note: The message sender won't be notified the message is sent. If you want a notification on the sender's end. Change the SendMessage method to this.

public async Task SendMessage(string sender, string receiver, string message)
{
    await Clients.Users(sender, receiver).SendAsync("ReceiveMessage", message);
}

These steps are only necessary if you need to change the default identifier. Otherwise, skip to the last step where you can simply send messages by passing userIds or connectionIds to SendMessage. For more

How to use Tomcat 8 in Eclipse?

I follow Jason's step, but not works.

And then I find the WTP Update site http://download.eclipse.org/webtools/updates/.

Help -> Install new software -> Add > WTP:http://download.eclipse.org/webtools/updates/ -> OK

Then Help -> Check for update, just works, I don't know whether Jason's affect this .

Set focus on textbox in WPF

None of this worked for me as I was using a grid rather than a StackPanel.

I finally found this example: http://spin.atomicobject.com/2013/03/06/xaml-wpf-textbox-focus/

and modified it to this:

In the 'Resources' section:

    <Style x:Key="FocusTextBox" TargetType="Grid">
        <Style.Triggers>
            <DataTrigger Binding="{Binding ElementName=textBoxName, Path=IsVisible}" Value="True">
                <Setter Property="FocusManager.FocusedElement" Value="{Binding ElementName=textBoxName}"/>
            </DataTrigger>
        </Style.Triggers>
    </Style>

In my grid definition:

<Grid Style="{StaticResource FocusTextBox}" />

"Permission Denied" trying to run Python on Windows 10

This is due to the way Windows App Execution Aliases work in Git-Bash.

It is a known issue in MSYS2 failing to access Windows reparse points with IO_REPARSE_TAG_APPEXECLINK

As a workaround, you can alias to a function invocation that uses cmd.exe under the hood.

Add the following to your ~/.bashrc file::

function python { cmd.exe /c "python $1 $2 $3";}

For python, I'd recommend just toggling off app execution aliases as in the accepted answer, but for libraries that are distributed exclusively through the windows store like winget, this is your best option.

Load RSA public key from file

This program is doing almost everything with Public and private keys. The der format can be obtained but saving raw data ( without encoding base64). I hope this helps programmers.

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.security.InvalidKeyException;
import java.security.KeyFactory;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.SignatureException;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;
import sun.security.pkcs.PKCS8Key;
import sun.security.pkcs10.PKCS10;
import sun.security.x509.X500Name;

import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;



/**
 * @author Desphilboy
 * DorOd bar shomA barobach
 *
 */
public class csrgenerator {

    private static PublicKey publickey= null;
    private static PrivateKey privateKey=null;
    //private static PKCS8Key privateKey=null;
    private static KeyPairGenerator kpg= null;
    private static ByteArrayOutputStream bs =null;
    private static csrgenerator thisinstance;
    private KeyPair keypair;
    private static PKCS10 pkcs10;
    private String signaturealgorithm= "MD5WithRSA";

    public String getSignaturealgorithm() {
        return signaturealgorithm;
    }



    public void setSignaturealgorithm(String signaturealgorithm) {
        this.signaturealgorithm = signaturealgorithm;
    }



    private csrgenerator() {
        try {
           kpg = KeyPairGenerator.getInstance("RSA");
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
            System.out.print("No such algorithm RSA in constructor csrgenerator\n");
        }
        kpg.initialize(2048);
        keypair = kpg.generateKeyPair();
        publickey = keypair.getPublic();
        privateKey = keypair.getPrivate();
    }



    /** Generates a new key pair 
    *
    * @param int bits 
    *   this is the number of bits in modulus must be 512, 1024, 2048  or so on 
    */
    public KeyPair generateRSAkys(int bits)
    {
          kpg.initialize(bits);
            keypair = kpg.generateKeyPair();
            publickey = keypair.getPublic();
            privateKey = keypair.getPrivate();
            KeyPair dup= keypair;
     return dup;
    }

     public static csrgenerator getInstance() {
            if (thisinstance == null)
                thisinstance = new csrgenerator();
            return thisinstance;
        }


     /**
      *  Returns a CSR as string  
      * @param cn  Common Name
      * @param OU  Organizational Unit 
      * @param Org  Organization
      * @param LocName Location name
      * @param Statename  State/Territory/Province/Region
      * @param Country    Country
      * @return     returns  csr as string.
      * @throws Exception
      */
     public String getCSR(String commonname, String organizationunit, String organization,String localname, String statename, String country ) throws Exception {
            byte[] csr = generatePKCS10(commonname, organizationunit, organization, localname, statename, country,signaturealgorithm);
            return new String(csr);
        }

     /** This function generates a new Certificate 
      * Signing Request. 
     *
     * @param CN
     *            Common Name, is X.509 speak for the name that distinguishes
     *            the Certificate best, and ties it to your Organization
     * @param OU
     *            Organizational unit
     * @param O
     *            Organization NAME
     * @param L
     *            Location
     * @param S
     *            State
     * @param C
     *            Country
     * @return    byte stream of generated request
     * @throws Exception
     */
    private static byte[] generatePKCS10(String CN, String OU, String O,String L, String S, String C,String sigAlg) throws Exception {
        // generate PKCS10 certificate request

        pkcs10 = new PKCS10(publickey);
       Signature   signature = Signature.getInstance(sigAlg);
        signature.initSign(privateKey);
        // common, orgUnit, org, locality, state, country
        //X500Name(String commonName, String organizationUnit,String organizationName,Local,State, String country)
        X500Name x500Name = new X500Name(CN, OU, O, L, S, C);
        pkcs10.encodeAndSign(x500Name,signature);
        bs = new ByteArrayOutputStream();
        PrintStream ps = new PrintStream(bs);
        pkcs10.print(ps);
        byte[] c = bs.toByteArray();
        try {
            if (ps != null)
                ps.close();
            if (bs != null)
                bs.close();
        } catch (Throwable th) {
        }
        return c;
    }

    public  PublicKey getPublicKey() {
        return publickey;
    }




    /**
     * @return
     */
    public PrivateKey getPrivateKey() {
        return privateKey;
    }

    /**
     * saves private key to a file
     * @param filename
     */
    public  void SavePrivateKey(String filename)
    {
        PKCS8EncodedKeySpec pemcontents=null;
        pemcontents= new PKCS8EncodedKeySpec( privateKey.getEncoded());
        PKCS8Key pemprivatekey= new  PKCS8Key( );
        try {
            pemprivatekey.decode(pemcontents.getEncoded());
        } catch (InvalidKeyException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        File file=new File(filename);
        try {

            file.createNewFile();
            FileOutputStream fos=new FileOutputStream(file);
            fos.write(pemprivatekey.getEncoded());
            fos.flush();
            fos.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }



    }



    /**
     * Saves Certificate Signing Request to a file;
     * @param filename  is a String containing full path to the file which will be created containing the CSR.
     */
    public void SaveCSR(String filename)
    {
        FileOutputStream fos=null;
        PrintStream ps=null;
        File file;
        try {

            file = new File(filename);
            file.createNewFile();
            fos = new FileOutputStream(file);
            ps= new PrintStream(fos);
        }catch (IOException e)
        {
            System.out.print("\n could not open the file "+ filename);
        }

        try {
            try {
                pkcs10.print(ps);
            } catch (SignatureException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            ps.flush();
            ps.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            System.out.print("\n cannot write to the file "+ filename);
            e.printStackTrace();

        }

        }


    /**
     * Saves both public key and private  key to file names specified
     * @param fnpub  file name of public key
     * @param fnpri  file name of private key
     * @throws IOException
     */
    public static void SaveKeyPair(String fnpub,String fnpri) throws IOException { 

// Store Public Key.
X509EncodedKeySpec x509EncodedKeySpec = new X509EncodedKeySpec(
publickey.getEncoded());
FileOutputStream fos = new FileOutputStream(fnpub);
fos.write(x509EncodedKeySpec.getEncoded());
fos.close();

// Store Private Key.
PKCS8EncodedKeySpec pkcs8EncodedKeySpec = new PKCS8EncodedKeySpec(privateKey.getEncoded());
fos = new FileOutputStream(fnpri);
fos.write(pkcs8EncodedKeySpec.getEncoded());
fos.close();
}


    /**
     * Reads a Private Key from a pem base64 encoded file.
     * @param filename name of the file to read.
     * @param algorithm Algorithm is usually "RSA"
     * @return returns the privatekey which is read from the file;
     * @throws Exception
     */
    public  PrivateKey getPemPrivateKey(String filename, String algorithm) throws Exception {
          File f = new File(filename);
          FileInputStream fis = new FileInputStream(f);
          DataInputStream dis = new DataInputStream(fis);
          byte[] keyBytes = new byte[(int) f.length()];
          dis.readFully(keyBytes);
          dis.close();

          String temp = new String(keyBytes);
          String privKeyPEM = temp.replace("-----BEGIN PRIVATE KEY-----", "");
          privKeyPEM = privKeyPEM.replace("-----END PRIVATE KEY-----", "");
          //System.out.println("Private key\n"+privKeyPEM);

          BASE64Decoder b64=new BASE64Decoder();
          byte[] decoded = b64.decodeBuffer(privKeyPEM);

          PKCS8EncodedKeySpec spec = new PKCS8EncodedKeySpec(decoded);
          KeyFactory kf = KeyFactory.getInstance(algorithm);
          return kf.generatePrivate(spec);
          }



    /**
     * Saves the private key to a pem file.
     * @param filename  name of the file to write the key into 
     * @param key the Private key to save.
     * @return  String representation of the pkcs8 object.
     * @throws Exception
     */
    public  String  SavePemPrivateKey(String filename) throws Exception {
        PrivateKey key=this.privateKey;
          File f = new File(filename);
          FileOutputStream fos = new FileOutputStream(f);
          DataOutputStream dos = new DataOutputStream(fos);


          byte[] keyBytes = key.getEncoded();
          PKCS8Key pkcs8= new PKCS8Key();
          pkcs8.decode(keyBytes);
          byte[] b=pkcs8.encode();

          BASE64Encoder b64=new BASE64Encoder();
          String  encoded = b64.encodeBuffer(b);

          encoded= "-----BEGIN PRIVATE KEY-----\r\n" + encoded + "-----END PRIVATE KEY-----";

         dos.writeBytes(encoded);
         dos.flush();
         dos.close();

          //System.out.println("Private key\n"+privKeyPEM);
        return pkcs8.toString();

          }


    /**
     * Saves a public key to a base64 encoded pem file
     * @param filename  name of the file 
     * @param key public key to be saved 
     * @return string representation of the pkcs8 object.
     * @throws Exception
     */
    public  String  SavePemPublicKey(String filename) throws Exception {
        PublicKey key=this.publickey;  
        File f = new File(filename);
          FileOutputStream fos = new FileOutputStream(f);
          DataOutputStream dos = new DataOutputStream(fos);


          byte[] keyBytes = key.getEncoded();
          BASE64Encoder b64=new BASE64Encoder();
          String  encoded = b64.encodeBuffer(keyBytes);

          encoded= "-----BEGIN PUBLIC KEY-----\r\n" + encoded + "-----END PUBLIC KEY-----";

         dos.writeBytes(encoded);
         dos.flush();
         dos.close();

          //System.out.println("Private key\n"+privKeyPEM);
      return  encoded.toString();

          }





       /**
     * reads a public key from a file
     * @param filename name of the file to read
     * @param algorithm is usually RSA
     * @return the read public key
     * @throws Exception
     */
    public  PublicKey getPemPublicKey(String filename, String algorithm) throws Exception {
          File f = new File(filename);
          FileInputStream fis = new FileInputStream(f);
          DataInputStream dis = new DataInputStream(fis);
          byte[] keyBytes = new byte[(int) f.length()];
          dis.readFully(keyBytes);
          dis.close();

          String temp = new String(keyBytes);
          String publicKeyPEM = temp.replace("-----BEGIN PUBLIC KEY-----\n", "");
          publicKeyPEM = publicKeyPEM.replace("-----END PUBLIC KEY-----", "");


          BASE64Decoder b64=new BASE64Decoder();
          byte[] decoded = b64.decodeBuffer(publicKeyPEM);

          X509EncodedKeySpec spec =
                new X509EncodedKeySpec(decoded);
          KeyFactory kf = KeyFactory.getInstance(algorithm);
          return kf.generatePublic(spec);
          }




    public static void main(String[] args) throws Exception {
        csrgenerator gcsr = csrgenerator.getInstance();
        gcsr.setSignaturealgorithm("SHA512WithRSA");
        System.out.println("Public Key:\n"+gcsr.getPublicKey().toString());

        System.out.println("Private Key:\nAlgorithm: "+gcsr.getPrivateKey().getAlgorithm().toString());
        System.out.println("Format:"+gcsr.getPrivateKey().getFormat().toString());
        System.out.println("To String :"+gcsr.getPrivateKey().toString());
        System.out.println("GetEncoded :"+gcsr.getPrivateKey().getEncoded().toString());
        BASE64Encoder encoder= new BASE64Encoder();
        String s=encoder.encodeBuffer(gcsr.getPrivateKey().getEncoded());
        System.out.println("Base64:"+s+"\n");

        String csr = gcsr.getCSR( "[email protected]","baxshi az xodam", "Xodam","PointCook","VIC" ,"AU");
        System.out.println("CSR Request Generated!!");
        System.out.println(csr);
        gcsr.SaveCSR("c:\\testdir\\javacsr.csr");
        String p=gcsr.SavePemPrivateKey("c:\\testdir\\java_private.pem");
        System.out.print(p);
        p=gcsr.SavePemPublicKey("c:\\testdir\\java_public.pem");
        privateKey= gcsr.getPemPrivateKey("c:\\testdir\\java_private.pem", "RSA");
        BASE64Encoder encoder1= new BASE64Encoder();
        String s1=encoder1.encodeBuffer(gcsr.getPrivateKey().getEncoded());
        System.out.println("Private Key in Base64:"+s1+"\n");
        System.out.print(p);


    }

    }

PostgreSQL: Show tables in PostgreSQL

use only see a tables

=> \dt

if want to see schema tables

=>\dt+

if you want to see specific schema tables

=>\dt schema_name.*

What is the "Temporary ASP.NET Files" folder for?

The CLR uses it when it is compiling at runtime. Here is a link to MSDN that explains further.

Update with two tables?

The answers didn't work for me with postgresql 9.1+

This is what I had to do (you can check more in the manual here)

UPDATE schema.TableA as A
SET "columnA" = "B"."columnB"
FROM schema.TableB as B
WHERE A.id = B.id;

You can omit the schema, if you are using the default schema for both tables.

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What good is an upstream?

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The upstream affects git merge and git rebase too

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How come master already has an upstream set?

But this doesn't work for new branches, i.e., branches with no remote-tracking branch yet.

Shouldn't Git just set that, now, as the upstream automatically?

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-----

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TL;DR: `git branch --set-upstream-to origin/solaris`

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The upstream affects `git merge` and `git rebase` too

The upstream affects `git pull`

The upstream affects `git status`

How come `master` already has an upstream set?