SyntaxFix

Programs & Examples On #Tinyint

tinyint is one of the Exact number data types that use integer data.

What is the difference between BIT and TINYINT in MySQL?

From Overview of Numeric Types;

BIT[(M)]

A bit-field type. M indicates the number of bits per value, from 1 to 64. The default is 1 if M is omitted.

This data type was added in MySQL 5.0.3 for MyISAM, and extended in 5.0.5 to MEMORY, InnoDB, BDB, and NDBCLUSTER. Before 5.0.3, BIT is a synonym for TINYINT(1).

TINYINT[(M)] [UNSIGNED] [ZEROFILL]

A very small integer. The signed range is -128 to 127. The unsigned range is 0 to 255.

Additionally consider this;

BOOL, BOOLEAN

These types are synonyms for TINYINT(1). A value of zero is considered false. Non-zero values are considered true.

BOOLEAN or TINYINT confusion

The Newest MySQL Versions have the new BIT data type in which you can specify the number of bits in the field, for example BIT(1) to use as Boolean type, because it can be only 0 or 1.

NodeJS: How to decode base64 encoded string back to binary?

As of Node.js v6.0.0 using the constructor method has been deprecated and the following method should instead be used to construct a new buffer from a base64 encoded string:

var b64string = /* whatever */;
var buf = Buffer.from(b64string, 'base64'); // Ta-da

For Node.js v5.11.1 and below

Construct a new Buffer and pass 'base64' as the second argument:

var b64string = /* whatever */;
var buf = new Buffer(b64string, 'base64'); // Ta-da

If you want to be clean, you can check whether from exists :

if (typeof Buffer.from === "function") {
    // Node 5.10+
    buf = Buffer.from(b64string, 'base64'); // Ta-da
} else {
    // older Node versions, now deprecated
    buf = new Buffer(b64string, 'base64'); // Ta-da
}

SQL Server Group By Month

Now your query is explicitly looking at only payments for year = 2010, however, I think you meant to have your Jan/Feb/Mar actually represent 2009. If so, you'll need to adjust this a bit for that case. Don't keep requerying the sum values for every column, just the condition of the date difference in months. Put the rest in the WHERE clause.

SELECT 
      SUM( case when DateDiff(m, PaymentDate, @start) = 0 
           then Amount else 0 end ) AS "Apr",
      SUM( case when DateDiff(m, PaymentDate, @start) = 1 
           then Amount else 0 end ) AS "May",
      SUM( case when DateDiff(m, PaymentDate, @start) = 2 
           then Amount else 0 end ) AS "June",
      SUM( case when DateDiff(m, PaymentDate, @start) = 3 
           then Amount else 0 end ) AS "July",
      SUM( case when DateDiff(m, PaymentDate, @start) = 4 
           then Amount else 0 end ) AS "Aug",
      SUM( case when DateDiff(m, PaymentDate, @start) = 5 
           then Amount else 0 end ) AS "Sep",
      SUM( case when DateDiff(m, PaymentDate, @start) = 6 
           then Amount else 0 end ) AS "Oct",
      SUM( case when DateDiff(m, PaymentDate, @start) = 7 
           then Amount else 0 end ) AS "Nov",
      SUM( case when DateDiff(m, PaymentDate, @start) = 8 
           then Amount else 0 end ) AS "Dec",
      SUM( case when DateDiff(m, PaymentDate, @start) = 9 
           then Amount else 0 end ) AS "Jan",
      SUM( case when DateDiff(m, PaymentDate, @start) = 10 
           then Amount else 0 end ) AS "Feb",
      SUM( case when DateDiff(m, PaymentDate, @start) = 11 
           then Amount else 0 end ) AS "Mar"
   FROM 
      Payments I
         JOIN Live L
            on I.LiveID = L.Record_Key
   WHERE 
          Year = 2010 
      AND UserID = 100

Generate random int value from 3 to 6

Simply:

DECLARE @MIN INT=3; --We define minimum value, it can be generated.
DECLARE @MAX INT=6; --We define maximum value, it can be generated.

SELECT @MIN+FLOOR((@MAX-@MIN+1)*RAND(CONVERT(VARBINARY,NEWID()))); --And then this T-SQL snippet generates an integer between minimum and maximum integer values.

You can change and edit this code for your needs.

How to preSelect an html dropdown list with php?

This answer is not relevant for particular recepient, but maybe useful for others. I had similiar issue with 'selecting' right 'option' by value returned from database. I solved it by adding additional tag with applied display:none.

<?php
$status =  "NOT_ON_LIST";

$text = "<html>
<head>
</head>
<body>
<select id=\"statuses\">
   <option value=\"status\" selected=\"selected\" style=\"display:none\">$status</option>
   <option value=\"status\">OK</option>
   <option value=\"status\">DOWN</option>
   <option value=\"status\">UNKNOWN</option>
</select>
</body>
</html>";

print $text;
?>

Div Background Image Z-Index Issue

To solve the issue, you are using the z-index on the footer and header, but you forgot about the position, if a z-index is to be used, the element must have a position:

Add to your footer and header this CSS:

position: relative;

EDITED:

Also noticed that the background image on the #backstretch has a negative z-index, don't use that, some browsers get really weird...

Remove From the #backstretch:

z-index: -999999;

Read a little bit about Z-Index here!

Could not find folder 'tools' inside SDK

By default it looks for the SDK tools in "C:\Documents and Settings\user\android-sdks". Some times we install it at another location. So you just have to select the correct path and it will done.

Format date as dd/MM/yyyy using pipes

In my case, I use in component file:

import {formatDate} from '@angular/common';

// Use your preferred locale
import localeFr from '@angular/common/locales/fr';
import { registerLocaleData } from '@angular/common';

// ....

displayDate: string;
registerLocaleData(localeFr, 'fr');
this.displayDate = formatDate(new Date(), 'EEEE d MMMM yyyy', 'fr');

And in the component HTML file

<h1> {{ displayDate }} </h1>

It works fine for me ;-)

PHP new line break in emails

Are you building this string using single or double quotes? \r and \n only work with double quotes, as well as embedded variables. For example:

$foo = 'bar';
echo 'Hello \n $foo!';

will output:

Hello \n $foo!

But:

$foo = 'bar';
echo "Hello \n $foo!";

will output:

Hello
bar!

What's the purpose of META-INF?

I've noticed that some Java libraries have started using META-INF as a directory in which to include configuration files that should be packaged and included in the CLASSPATH along with JARs. For example, Spring allows you to import XML Files that are on the classpath using:

<import resource="classpath:/META-INF/cxf/cxf.xml" />
<import resource="classpath:/META-INF/cxf/cxf-extensions-*.xml" />

In this example, I'm quoting straight out of the Apache CXF User Guide. On a project I worked on in which we had to allow multiple levels of configuration via Spring, we followed this convention and put our configuration files in META-INF.

When I reflect on this decision, I don't know what exactly would be wrong with simply including the configuration files in a specific Java package, rather than in META-INF. But it seems to be an emerging de facto standard; either that, or an emerging anti-pattern :-)

SQLAlchemy: how to filter date field?

if you want to get the whole period:

    from sqlalchemy import and_, func

    query = DBSession.query(User).filter(and_(func.date(User.birthday) >= '1985-01-17'),\
                                              func.date(User.birthday) <= '1988-01-17'))

That means range: 1985-01-17 00:00 - 1988-01-17 23:59

How to get value at a specific index of array In JavaScript?

You can use [];

var indexValue = Index[1];

How to insert a line break in a SQL Server VARCHAR/NVARCHAR string

All of these options work depending on your situation, but you may not see any of them work if you're using SSMS (as mentioned in some comments SSMS hides CR/LFs)

So rather than driving yourself round the bend, Check this setting in

Tools | Options

which will replace the

Google Maps API 3 - Custom marker color for default (dot) marker

As others have mentioned, vokimon's answer is great but unfortunately Google Maps is a bit slow when there are many SymbolPath/SVG-based markers at once.

It looks like using a Data URI is much faster, approximately on par with PNGs.

Also, since it's a full SVG document, it's possible to use a proper filled circle for the dot. The path is modified so it is no longer offset to the top-left, so the anchor needs to be defined.

Here's a modified version that generates these markers:

var coloredMarkerDef = {
    svg: [
        '<svg viewBox="0 0 22 41" width="22px" height="41px" xmlns="http://www.w3.org/2000/svg">',
            '<path d="M 11,41 c -2,-20 -10,-22 -10,-30 a 10,10 0 1 1 20,0 c 0,8 -8,10 -10,30 z" fill="{fillColor}" stroke="#ffffff" stroke-width="1.5"/>',
            '<circle cx="11" cy="11" r="3"/>',
        '</svg>'
    ].join(''),
    anchor: {x: 11, y: 41},
    size: {width: 22, height: 41}
};

var getColoredMarkerSvg = function(color) {
    return coloredMarkerDef.svg.replace('{fillColor}', color);
};

var getColoredMarkerUri = function(color) {
    return 'data:image/svg+xml,' + encodeURIComponent(getColoredMarkerSvg(color));
};

var getColoredMarkerIcon = function(color) {
    return {
        url: getColoredMarkerUri(color),
        anchor: coloredMarkerDef.anchor,
        size: coloredMarkerDef.size,
        scaledSize: coloredMarkerDef.size
    }
};

Usage:

var marker = new google.maps.Marker({
    map: map,
    position: new google.maps.LatLng(latitude, longitude),
    icon: getColoredMarkerIcon("#FFF")
});

The downside, much like a PNG image, is the whole rectangle is clickable. In theory it's not too difficult to trace the SVG path and generate a MarkerShape polygon.

How can I prevent java.lang.NumberFormatException: For input string: "N/A"?

Obviously you can't parse N/A to int value. you can do something like following to handle that NumberFormatException .

   String str="N/A";
   try {
        int val=Integer.parseInt(str);
   }catch (NumberFormatException e){
       System.out.println("not a number"); 
   }

How to make a link open multiple pages when clicked

If you prefer to inform the visitor which links will be opened, you can use a JS function reading links from an html element. You can even let the visitor write/modify the links as seen below:

<script type="text/javascript"> 
    function open_all_links() {
        var x = document.getElementById('my_urls').value.split('\n');
        for (var i = 0; i < x.length; i++)
            if (x[i].indexOf('.') > 0)
            if (x[i].indexOf('://') < 0)
                window.open('http://' + x[i]);
            else
                window.open(x[i]);
    }
</script>



<form method="post" name="input" action=""> 
    <textarea id="my_urls" rows="4" placeholder="enter links in each row..."></textarea>
    <input value="open all now" type="button" onclick="open_all_links();">
</form>

Servlet for serving static content

I've had good results with FileServlet, as it supports pretty much all of HTTP (etags, chunking, etc.).

Match the path of a URL, minus the filename extension

|(?<=\w)/.+(?=\.\w+$)|

  • select everything from the first literal '/' preceded by
  • look behind a Word(\w) character
  • until followed by a look ahead
    • literal '.' appended by
    • one or more Word(\w) characters
    • before the end $
  re> |(?<=\w)/.+(?=\.\w+$)|
Compile time 0.0011 milliseconds
Memory allocation (code space): 32
  Study time 0.0002 milliseconds
Capturing subpattern count = 0
No options
First char = '/'
No need char
Max lookbehind = 1
Subject length lower bound = 2
No set of starting bytes
data> http://php.net/manual/en/function.preg-match.php
Execute time 0.0007 milliseconds
 0: /manual/en/function.preg-match

|//[^/]*(.*)\.\w+$|

  • find two literal '//' followed by anything but a literal '/'
  • select everything until
  • find literal '.' followed by only Word \w characters before the end $
  re> |//[^/]*(.*)\.\w+$|
Compile time 0.0010 milliseconds
Memory allocation (code space): 28
  Study time 0.0002 milliseconds
Capturing subpattern count = 1
No options
First char = '/'
Need char = '.'
Subject length lower bound = 4
No set of starting bytes
data> http://php.net/manual/en/function.preg-match.php
Execute time 0.0005 milliseconds
 0: //php.net/manual/en/function.preg-match.php
 1: /manual/en/function.preg-match

|/[^/]+(.*)\.|

  • find literal '/' followed by at least 1 or more non literal '/'
  • aggressive select everything before the last literal '.'
  re> |/[^/]+(.*)\.|
Compile time 0.0008 milliseconds
Memory allocation (code space): 23
  Study time 0.0002 milliseconds
Capturing subpattern count = 1
No options
First char = '/'
Need char = '.'
Subject length lower bound = 3
No set of starting bytes
data> http://php.net/manual/en/function.preg-match.php
Execute time 0.0005 milliseconds
 0: /php.net/manual/en/function.preg-match.
 1: /manual/en/function.preg-match

|/[^/]+\K.*(?=\.)|

  • find literal '/' followed by at least 1 or more non literal '/'
  • Reset select start \K
  • aggressive select everything before
  • look ahead last literal '.'
  re> |/[^/]+\K.*(?=\.)|
Compile time 0.0009 milliseconds
Memory allocation (code space): 22
  Study time 0.0002 milliseconds
Capturing subpattern count = 0
No options
First char = '/'
No need char
Subject length lower bound = 2
No set of starting bytes
data> http://php.net/manual/en/function.preg-match.php
Execute time 0.0005 milliseconds
 0: /manual/en/function.preg-match

|\w+\K/.*(?=\.)|

  • find one or more Word(\w) characters before a literal '/'
  • reset select start \K
  • select literal '/' followed by
  • anything before
  • look ahead last literal '.'
  re> |\w+\K/.*(?=\.)|
Compile time 0.0009 milliseconds
Memory allocation (code space): 22
  Study time 0.0003 milliseconds
Capturing subpattern count = 0
No options
No first char
Need char = '/'
Subject length lower bound = 2
Starting byte set: 0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P 
  Q R S T U V W X Y Z _ a b c d e f g h i j k l m n o p q r s t u v w x y z 
data> http://php.net/manual/en/function.preg-match.php
Execute time 0.0011 milliseconds
 0: /manual/en/function.preg-match

How can I find all of the distinct file extensions in a folder hierarchy?

I don't think this one was mentioned yet:

find . -type f -exec sh -c 'echo "${0##*.}"' {} \; | sort | uniq -c

HTML Table cellspacing or padding just top / bottom

Cellspacing is all around the cell and cannot be changed (i.e. if it's set to one, there will be 1 pixel of space on all sides). Padding can be specified discreetly (e.g. padding-top, padding-bottom, padding-left, and padding-right; or padding: [top] [right] [bottom] [left];).

Lodash - difference between .extend() / .assign() and .merge()

It might be also helpful to consider what they do from a semantic point of view:

_.assign

   will assign the values of the properties of its second parameter and so on,
   as properties with the same name of the first parameter. (shallow copy & override)

_.merge

   merge is like assign but does not assign objects but replicates them instead.
  (deep copy)

_.defaults

   provides default values for missing values.
   so will assign only values for keys that do not exist yet in the source.

_.defaultsDeep

   works like _defaults but like merge will not simply copy objects
   and will use recursion instead.

I believe that learning to think of those methods from the semantic point of view would let you better "guess" what would be the behavior for all the different scenarios of existing and non existing values.

Explaining the 'find -mtime' command

To find all files modified in the last 24 hours use the one below. The -1 here means changed 1 day or less ago.

find . -mtime -1 -ls

Google Maps v2 - set both my location and zoom in

@CommonsWare's answer doesn't not actually work. I found that this is working properly :

map.moveCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(-33.88,151.21), 15));

Label encoding across multiple columns in scikit-learn

A short way to LabelEncoder() multiple columns with a dict(): 

from sklearn.preprocessing import LabelEncoder
le_dict = {col: LabelEncoder() for col in columns }
for col in columns:
    le_dict[col].fit_transform(df[col])

and you can use this le_dict to labelEncode any other column: 

le_dict[col].transform(df_another[col])

Rails: Get Client IP address

I found request.env['HTTP_X_FORWARDED_FOR'] very useful too in cases when request.remote_ip returns 127.0.0.1

PHP - Get bool to echo false when false

This is the easiest way to do this:

$text = var_export($bool_value,true);
echo $text;

or

var_export($bool_value)

If the second argument is not true, it will output the result directly.

subsampling every nth entry in a numpy array

You can use numpy's slicing, simply start:stop:step.

>>> xs
array([1, 2, 3, 4, 1, 2, 3, 4, 1, 2, 3, 4])
>>> xs[1::4]
array([2, 2, 2])

This creates a view of the the original data, so it's constant time. It'll also reflect changes to the original array and keep the whole original array in memory:

>>> a
array([1, 2, 3, 4, 5])
>>> b = a[::2]         # O(1), constant time
>>> b[:] = 0           # modifying the view changes original array
>>> a                  # original array is modified
array([0, 2, 0, 4, 0])

so if either of the above things are a problem, you can make a copy explicitly:

>>> a
array([1, 2, 3, 4, 5])
>>> b = a[::2].copy()  # explicit copy, O(n)
>>> b[:] = 0           # modifying the copy
>>> a                  # original is intact
array([1, 2, 3, 4, 5])

This isn't constant time, but the result isn't tied to the original array. The copy also contiguous in memory, which can make some operations on it faster.

Create a OpenSSL certificate on Windows

Consider using certificate depot web app to easily create private key and certificate based on it: http://www.cert-depot.com/

It can also create a PFX for you.

Disclaimer: I am the creator of certificate depot.

Fatal error: Call to undefined function base_url() in C:\wamp\www\Test-CI\application\views\layout.php on line 5

Go to application/config/autoload.php

$autoload['helper'] = array('url');

add this on top anywhere

and at this in controller

function __construct()
{
    parent::__construct();
$this->load->helper('url');

}

Get source jar files attached to Eclipse for Maven-managed dependencies

If you are using meclipse do

window --> maven --> Download Artifact Sources (select check)

(If you still get attach source window, then click on attach file button and close the attach source window. The next time you try to see the source it will open the correct source)

Surajz

What's the best way to get the last element of an array without deleting it?

Simply: $last_element = end((array_values($array)))

Doesn't reset the array and doesn't gives STRICT warnings.

PS. Since the most voted answer still hasn't the double parenthesis, I submitted this answer.

Android Gradle 5.0 Update:Cause: org.jetbrains.plugins.gradle.tooling.util

I upgraded my IntelliJ Version from 2018.1 to 2018.3.6. It works !

How to index characters in a Golang string?

The general solution to interpreting a char as a string is string("HELLO"[1]).

Rich's solution also works, of course.

Getting Error - ORA-01858: a non-numeric character was found where a numeric was expected

I added TO_DATE and it resolved issue.

Before modification - due to below condition i got this error

record_update_dt>='05-May-2017'

After modification - after adding to_date, issue got resolved.

record_update_dt>=to_date('05-May-2017','DD-Mon-YYYY')

Random integer in VB.NET

Microsoft Example Rnd Function

https://msdn.microsoft.com/en-us/library/f7s023d2%28v=vs.90%29.aspx

1- Initialize the random-number generator.

Randomize()

2 - Generate random value between 1 and 6. 

Dim value As Integer = CInt(Int((6 * Rnd()) + 1))

How to get image height and width using java?

To get a Buffered Image with ImageIO.read is a very heavy method, as it's creating a complete uncompressed copy of the image in memory. For png's you may also use pngj and the code:

if (png)
    PngReader pngr = new PngReader(file);
    width = pngr.imgInfo.cols;
    height = pngr.imgInfo.rows;
    pngr.close();
}

Relationship between hashCode and equals method in Java

The contract is that if obj1.equals(obj2) then obj1.hashCode() == obj2.hashCode() , it is mainly for performance reasons, as maps are mainly using hashCode method to compare entries keys.

How to check for DLL dependency?

dumpbin from Visual Studio tools (VC\bin folder) can help here:

dumpbin /dependents your_dll_file.dll

How to find the php.ini file used by the command line?

Just run php --ini and look for Loaded Configuration File in output for the location of php.ini used by your CLI

integrating barcode scanner into php application?

PHP can be easily utilized for reading bar codes printed on paper documents. Connecting manual barcode reader to the computer via USB significantly extends usability of PHP (or any other web programming language) into tasks involving document and product management, like finding a book records in the database or listing all bills for a particular customer.

Following sections briefly describe process of connecting and using manual bar code reader with PHP.

The usage of bar code scanners described in this article are in the same way applicable to any web programming language, such as ASP, Python or Perl. This article uses only PHP since all tests have been done with PHP applications.

What is a bar code reader (scanner)

Bar code reader is a hardware pluggable into computer that sends decoded bar code strings into computer. The trick is to know how to catch that received string. With PHP (and any other web programming language) the string will be placed into focused input HTML element in browser. Thus to catch received bar code string, following must be done:

just before reading the bar code, proper input element, such as INPUT TEXT FIELD must be focused (mouse cursor is inside of the input field). once focused, start reading the code when the code is recognized (bar code reader usually shortly beeps), it is send to the focused input field. By default, most of bar code readers will append extra special character to decoded bar code string called CRLF (ENTER). For example, if decoded bar code is "12345AB", then computer will receive "12345ABENTER". Appended character ENTER (or CRLF) emulates pressing the key ENTER causing instant submission of the HTML form:

<form action="search.php" method="post">
    <input name="documentID" onmouseover="this.focus();" type="text">
</form>

Choosing the right bar code scanner

When choosing bar code reader, one should consider what types of bar codes will be read with it. Some bar codes allow only numbers, others will not have checksum, some bar codes are difficult to print with inkjet printers, some barcode readers have narrow reading pane and cannot read for example barcodes with length over 10 cm. Most of barcode readers support common barcodes, such as EAN8, EAN13, CODE 39, Interleaved 2/5, Code 128 etc.

For office purposes, the most suitable barcodes seem to be those supporting full range of alphanumeric characters, which might be:

  • code 39 - supports 0-9, uppercased A-Z, and few special characters (dash, comma, space, $, /, +, %, *)
  • code 128 - supports 0-9, a-z, A-Z and other extended characters

Other important things to note:

  • make sure all standard barcodes are supported, at least CODE39, CODE128, Interleaved25, EAN8, EAN13, PDF417, QRCODE.
  • use only standard USB plugin cables. RS232 interfaces are meant for industrial usage, rather than connecting to single PC.
  • the cable should be long enough, at least 1.5 m - the longer the better.
  • bar code reader plugged into computer should not require other power supply - it should power up simply by connecting to PC via USB.
  • if you also need to print bar code into generated PDF documents, you can use TCPDF open source library that supports most of common 2D bar codes.

Installing scanner drivers

Installing manual bar code reader requires installing drivers for your particular operating system and should be normally supplied with purchased bar code reader.

Once installed and ready, bar code reader turns on signal LED light. Reading the barcode starts with pressing button for reading.

Scanning the barcode - how does it work?

STEP 1 - Focused input field ready for receiving character stream from bar code scanner:

step 1

STEP 2 - Received barcode string from bar code scanner is immediatelly submitted for search into database, which creates nice "automated" effect:

step 2

STEP 3 - Results returned after searching the database with submitted bar code:

step 3

Conclusion

It seems, that utilization of PHP (and actually any web programming language) for scanning the bar codes has been quite overlooked so far. However, with natural support of emulated keypress (ENTER/CRLF) it is very easy to automate collecting & processing recognized bar code strings via simple HTML (GUI) fomular.

The key is to understand, that recognized bar code string is instantly sent to the focused HTML element, such as INPUT text field with appended trailing character ASCII 13 (=ENTER/CRLF, configurable option), which instantly sends input text field with populated received barcode as a HTML formular to any other script for further processing.

Reference: http://www.synet.sk/php/en/280-barcode-reader-scanner-in-php

Hope this helps you :)

Postgresql tables exists, but getting "relation does not exist" when querying

I hit this error and it turned out my connection string was pointing to another database, obviously the table didn't exist there.

I spent a few hours on this and no one else has mentioned to double check your connection string.

Print values for multiple variables on the same line from within a for-loop

As an additional note, there is no need for the for loop because of R's vectorization.

This:

P <- 243.51
t <- 31 / 365
n <- 365

for (r in seq(0.15, 0.22, by = 0.01))    
     A <- P * ((1 + (r/ n))^ (n * t))
     interest <- A - P
}

is equivalent to:

P <- 243.51
t <- 31 / 365
n <- 365
r <- seq(0.15, 0.22, by = 0.01)
A <- P * ((1 + (r/ n))^ (n * t))
interest <- A - P

Because r is a vector, the expression above containing it is performed for all values of the vector.

How to cache Google map tiles for offline usage?

Unfortunately, I found this link which appears to indicate that we cannot cache these locally, therefore making this question moot.

http://support.google.com/enterprise/doc/gme/terms/maps_purchase_agreement.html

4.4 Cache Restrictions. Customer may not pre-fetch, retrieve, cache, index, or store any Content, or portion of the Services with the exception being Customer may store limited amounts of Content solely to improve the performance of the Customer Implementation due to network latency, and only if Customer does so temporarily, securely, and in a manner that (a) does not permit use of the Content outside of the Services; (b) is session-based only (once the browser is closed, any additional storage is prohibited); (c) does not manipulate or aggregate any Content or portion of the Services; (d) does not prevent Google from accurately tracking Page Views; and (e) does not modify or adjust attribution in any way.

So it appears we cannot use Google map tiles offline, legally.

MySQL: Error dropping database (errno 13; errno 17; errno 39)

In my case it was due to 'lower_case_table_names' parameter.

The error number 39 thrown out when I tried to drop the databases which consists upper case table names with lower_case_table_names parameter is enabled.

This is fixed by reverting back the lower case parameter changes to the previous state.

How to concatenate strings in twig

To mix strings, variables and translations I simply do the following:

    {% set add_link = '
    <a class="btn btn-xs btn-icon-only" 
       title="' ~ 'string.to_be_translated'|trans ~ '" 
       href="' ~ path('acme_myBundle_link',{'link':link.id})  ~ '">
    </a>
    ' %}

Despite everything being mixed up, it works like a charm.

Disabling Chrome Autofill

None of the other solutions to these question worked for me.

The only think that worked is this one:

It removes "name" and "id" attributes from elements and assigns them back after 1ms. Put this in document get ready.

$(document).ready(function() {
    $('form[autocomplete="off"] input, input[autocomplete="off"]').each(function () {

                var input = this;
                var name = $(input).attr('name');
                var id = $(input).attr('id');

                $(input).removeAttr('name');
                $(input).removeAttr('id');

                setTimeout(function () {
                    $(input).attr('name', name);
                    $(input).attr('id', id);
                }, 1);
            });
});

How to get input from user at runtime

TRY THIS 

declare 
  a number;
begin
  a := :a;
dbms_output.put_line('Inputed Number is >> '|| a);
end;
/  

OR

declare 
  a number;
begin
  a := :x;
dbms_output.put_line('Inputed Number is >> '|| a);
end;
/

finding the type of an element using jQuery

The following will return true if the element is an input:

$("#elementId").is("input")

or you can use the following to get the name of the tag:

$("#elementId").get(0).tagName

How do I use SELECT GROUP BY in DataTable.Select(Expression)?

DataTable's Select method only supports simple filtering expressions like {field} = {value}. It does not support complex expressions, let alone SQL/Linq statements.

You can, however, use Linq extension methods to extract a collection of DataRows then create a new DataTable.

dt = dt.AsEnumerable()
       .GroupBy(r => new {Col1 = r["Col1"], Col2 = r["Col2"]})
       .Select(g => g.OrderBy(r => r["PK"]).First())
       .CopyToDataTable();

How do you compare structs for equality in C?

You may be tempted to use memcmp(&a, &b, sizeof(struct foo)), but it may not work in all situations. The compiler may add alignment buffer space to a structure, and the values found at memory locations lying in the buffer space are not guaranteed to be any particular value.

But, if you use calloc or memset the full size of the structures before using them, you can do a shallow comparison with memcmp (if your structure contains pointers, it will match only if the address the pointers are pointing to are the same).

R: how to label the x-axis of a boxplot

If you read the help file for ?boxplot, you'll see there is a names= parameter.

     boxplot(apple, banana, watermelon, names=c("apple","banana","watermelon"))

enter image description here

Is there a WebSocket client implemented for Python?

http://pypi.python.org/pypi/websocket-client/

Ridiculously easy to use.

 sudo pip install websocket-client

Sample client code:

#!/usr/bin/python

from websocket import create_connection
ws = create_connection("ws://localhost:8080/websocket")
print "Sending 'Hello, World'..."
ws.send("Hello, World")
print "Sent"
print "Receiving..."
result =  ws.recv()
print "Received '%s'" % result
ws.close()

Sample server code:

#!/usr/bin/python
import websocket
import thread
import time

def on_message(ws, message):
    print message

def on_error(ws, error):
    print error

def on_close(ws):
    print "### closed ###"

def on_open(ws):
    def run(*args):
        for i in range(30000):
            time.sleep(1)
            ws.send("Hello %d" % i)
        time.sleep(1)
        ws.close()
        print "thread terminating..."
    thread.start_new_thread(run, ())


if __name__ == "__main__":
    websocket.enableTrace(True)
    ws = websocket.WebSocketApp("ws://echo.websocket.org/",
                                on_message = on_message,
                                on_error = on_error,
                                on_close = on_close)
    ws.on_open = on_open

    ws.run_forever()

How to clear variables in ipython?

EDITED after @ErdemKAYA comment.

To erase a variable, use the magic command:

%reset_selective <regular_expression>

The variables that are erased from the namespace are the one matching the given <regular_expression>.

Therefore

%reset_selective -f a

will erase all the variables containing an a.

Instead, to erase only a and not aa:

In: a, aa = 1, 2
In: %reset_selective -f "^a$"
In: a  # raise NameError
In: aa  # returns 2

see as well %reset_selective? for more examples and https://regexone.com/ for a regex tutorial.

To erase all the variables in the namespace see:

%reset?

Authentication plugin 'caching_sha2_password' is not supported

If you are looking for the solution of following error

ERROR: Could not install packages due to an EnvironmentError: [WinError 5] Acces s is denied: 'D:\softwares\spider\Lib\site-packages\libmysql.dll' Consider using the --user option or check the permissions.

The solution: You should add --user if you find an access-denied error.

 pip install --user mysql-connector-python

paste this command into cmd and solve your problem

Create directory if it does not exist

 
$path = "C:\temp\NewFolder"
If(!(test-path $path))
{
      New-Item -ItemType Directory -Force -Path $path
}

Test-Path checks to see if the path exists. When it does not, it will create a new directory.

What is the best Java email address validation method?

I ported some of the code in Zend_Validator_Email:

@FacesValidator("emailValidator")
public class EmailAddressValidator implements Validator {

    private String localPart;
    private String hostName;
    private boolean domain = true;

    Locale locale;
    ResourceBundle bundle;

    private List<FacesMessage> messages = new ArrayList<FacesMessage>();

    private HostnameValidator hostnameValidator;

    @Override
    public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {
        setOptions(component);
        String email    = (String) value;
        boolean result  = true;
        Pattern pattern = Pattern.compile("^(.+)@([^@]+[^.])$");
        Matcher matcher = pattern.matcher(email);

        locale = context.getViewRoot().getLocale();
        bundle = ResourceBundle.getBundle("com.myapp.resources.validationMessages", locale);

        boolean length = true;
        boolean local  = true;

        if (matcher.find()) {
            localPart   = matcher.group(1);
            hostName    = matcher.group(2);

            if (localPart.length() > 64 || hostName.length() > 255) {
                length          = false;
                addMessage("enterValidEmail", "email.AddressLengthExceeded");
            } 

            if (domain == true) {
                hostnameValidator = new HostnameValidator();
                hostnameValidator.validate(context, component, hostName);
            }

            local = validateLocalPart();

            if (local && length) {
                result = true;
            } else {
                result = false;
            }

        } else {
            result          = false;
            addMessage("enterValidEmail", "invalidEmailAddress");
        }

        if (result == false) {
            throw new ValidatorException(messages);
        }

    }

    private boolean validateLocalPart() {
        // First try to match the local part on the common dot-atom format
        boolean result = false;

        // Dot-atom characters are: 1*atext *("." 1*atext)
        // atext: ALPHA / DIGIT / and "!", "#", "$", "%", "&", "'", "*",
        //        "+", "-", "/", "=", "?", "^", "_", "`", "{", "|", "}", "~"
        String atext = "a-zA-Z0-9\\u0021\\u0023\\u0024\\u0025\\u0026\\u0027\\u002a"
                + "\\u002b\\u002d\\u002f\\u003d\\u003f\\u005e\\u005f\\u0060\\u007b"
                + "\\u007c\\u007d\\u007e";
        Pattern regex = Pattern.compile("^["+atext+"]+(\\u002e+["+atext+"]+)*$");
        Matcher matcher = regex.matcher(localPart);
        if (matcher.find()) {
            result = true;
        } else {
            // Try quoted string format

            // Quoted-string characters are: DQUOTE *([FWS] qtext/quoted-pair) [FWS] DQUOTE
            // qtext: Non white space controls, and the rest of the US-ASCII characters not
            //   including "\" or the quote character
            String noWsCtl = "\\u0001-\\u0008\\u000b\\u000c\\u000e-\\u001f\\u007f";
            String qText = noWsCtl + "\\u0021\\u0023-\\u005b\\u005d-\\u007e";
            String ws = "\\u0020\\u0009";

            regex = Pattern.compile("^\\u0022(["+ws+qText+"])*["+ws+"]?\\u0022$");
            matcher = regex.matcher(localPart);
            if (matcher.find()) {
                result = true;
            } else {
                addMessage("enterValidEmail", "email.AddressDotAtom");
                addMessage("enterValidEmail", "email.AddressQuotedString");
                addMessage("enterValidEmail", "email.AddressInvalidLocalPart");
            }
        }

        return result;
    }

    private void addMessage(String detail, String summary) {
        String detailMsg = bundle.getString(detail);
        String summaryMsg = bundle.getString(summary);
        messages.add(new FacesMessage(FacesMessage.SEVERITY_ERROR, summaryMsg, detailMsg));
    }

    private void setOptions(UIComponent component) {
        Boolean domainOption = Boolean.valueOf((String) component.getAttributes().get("domain"));
        //domain = (domainOption == null) ? true : domainOption.booleanValue();
    }
}

With a hostname validator as follows:

@FacesValidator("hostNameValidator")
public class HostnameValidator implements Validator {

    private Locale locale;
    private ResourceBundle bundle;
    private List<FacesMessage> messages;
    private boolean checkTld = true;
    private boolean allowLocal = false;
    private boolean allowDNS = true;
    private String tld;
    private String[] validTlds = {"ac", "ad", "ae", "aero", "af", "ag", "ai",
        "al", "am", "an", "ao", "aq", "ar", "arpa", "as", "asia", "at", "au",
        "aw", "ax", "az", "ba", "bb", "bd", "be", "bf", "bg", "bh", "bi", "biz",
        "bj", "bm", "bn", "bo", "br", "bs", "bt", "bv", "bw", "by", "bz", "ca",
        "cat", "cc", "cd", "cf", "cg", "ch", "ci", "ck", "cl", "cm", "cn", "co",
        "com", "coop", "cr", "cu", "cv", "cx", "cy", "cz", "de", "dj", "dk",
        "dm", "do", "dz", "ec", "edu", "ee", "eg", "er", "es", "et", "eu", "fi",
        "fj", "fk", "fm", "fo", "fr", "ga", "gb", "gd", "ge", "gf", "gg", "gh",
        "gi", "gl", "gm", "gn", "gov", "gp", "gq", "gr", "gs", "gt", "gu", "gw",
        "gy", "hk", "hm", "hn", "hr", "ht", "hu", "id", "ie", "il", "im", "in",
        "info", "int", "io", "iq", "ir", "is", "it", "je", "jm", "jo", "jobs",
        "jp", "ke", "kg", "kh", "ki", "km", "kn", "kp", "kr", "kw", "ky", "kz",
        "la", "lb", "lc", "li", "lk", "lr", "ls", "lt", "lu", "lv", "ly", "ma",
        "mc", "md", "me", "mg", "mh", "mil", "mk", "ml", "mm", "mn", "mo",
        "mobi", "mp", "mq", "mr", "ms", "mt", "mu", "museum", "mv", "mw", "mx",
        "my", "mz", "na", "name", "nc", "ne", "net", "nf", "ng", "ni", "nl",
        "no", "np", "nr", "nu", "nz", "om", "org", "pa", "pe", "pf", "pg", "ph",
        "pk", "pl", "pm", "pn", "pr", "pro", "ps", "pt", "pw", "py", "qa", "re",
        "ro", "rs", "ru", "rw", "sa", "sb", "sc", "sd", "se", "sg", "sh", "si",
        "sj", "sk", "sl", "sm", "sn", "so", "sr", "st", "su", "sv", "sy", "sz",
        "tc", "td", "tel", "tf", "tg", "th", "tj", "tk", "tl", "tm", "tn", "to",
        "tp", "tr", "travel", "tt", "tv", "tw", "tz", "ua", "ug", "uk", "um",
        "us", "uy", "uz", "va", "vc", "ve", "vg", "vi", "vn", "vu", "wf", "ws",
        "ye", "yt", "yu", "za", "zm", "zw"};
    private Map<String, Map<Integer, Integer>> idnLength;

    private void init() {
        Map<Integer, Integer> biz = new HashMap<Integer, Integer>();
        biz.put(5, 17);
        biz.put(11, 15);
        biz.put(12, 20);

        Map<Integer, Integer> cn = new HashMap<Integer, Integer>();
        cn.put(1, 20);

        Map<Integer, Integer> com = new HashMap<Integer, Integer>();
        com.put(3, 17);
        com.put(5, 20);

        Map<Integer, Integer> hk = new HashMap<Integer, Integer>();
        hk.put(1, 15);

        Map<Integer, Integer> info = new HashMap<Integer, Integer>();
        info.put(4, 17);

        Map<Integer, Integer> kr = new HashMap<Integer, Integer>();
        kr.put(1, 17);

        Map<Integer, Integer> net = new HashMap<Integer, Integer>();
        net.put(3, 17);
        net.put(5, 20);

        Map<Integer, Integer> org = new HashMap<Integer, Integer>();
        org.put(6, 17);

        Map<Integer, Integer> tw = new HashMap<Integer, Integer>();
        tw.put(1, 20);

        Map<Integer, Integer> idn1 = new HashMap<Integer, Integer>();
        idn1.put(1, 20);

        Map<Integer, Integer> idn2 = new HashMap<Integer, Integer>();
        idn2.put(1, 20);

        Map<Integer, Integer> idn3 = new HashMap<Integer, Integer>();
        idn3.put(1, 20);

        Map<Integer, Integer> idn4 = new HashMap<Integer, Integer>();
        idn4.put(1, 20);

        idnLength = new HashMap<String, Map<Integer, Integer>>();

        idnLength.put("BIZ", biz);
        idnLength.put("CN", cn);
        idnLength.put("COM", com);
        idnLength.put("HK", hk);
        idnLength.put("INFO", info);
        idnLength.put("KR", kr);
        idnLength.put("NET", net);
        idnLength.put("ORG", org);
        idnLength.put("TW", tw);
        idnLength.put("?????", idn1);
        idnLength.put("??", idn2);
        idnLength.put("??", idn3);
        idnLength.put("??", idn4);

        messages = new ArrayList<FacesMessage>();
    }

    public HostnameValidator() {
        init();
    }

    @Override
    public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {
        String hostName = (String) value;

        locale = context.getViewRoot().getLocale();
        bundle = ResourceBundle.getBundle("com.myapp.resources.validationMessages", locale);

        Pattern ipPattern = Pattern.compile("^[0-9a-f:\\.]*$", Pattern.CASE_INSENSITIVE);
        Matcher ipMatcher = ipPattern.matcher(hostName);
        if (ipMatcher.find()) {
            addMessage("hostname.IpAddressNotAllowed");
            throw new ValidatorException(messages);
        }

        boolean result = false;

        // removes last dot (.) from hostname 
        hostName = hostName.replaceAll("(\\.)+$", "");
        String[] domainParts = hostName.split("\\.");

        boolean status = false;

        // Check input against DNS hostname schema
        if ((domainParts.length > 1) && (hostName.length() > 4) && (hostName.length() < 255)) {
            status = false;

            dowhile:
            do {
                // First check TLD
                int lastIndex = domainParts.length - 1;
                String domainEnding = domainParts[lastIndex];
                Pattern tldRegex = Pattern.compile("([^.]{2,10})", Pattern.CASE_INSENSITIVE);
                Matcher tldMatcher = tldRegex.matcher(domainEnding);
                if (tldMatcher.find() || domainEnding.equals("?????")
                        || domainEnding.equals("??")
                        || domainEnding.equals("??")
                        || domainEnding.equals("??")) {



                    // Hostname characters are: *(label dot)(label dot label); max 254 chars
                    // label: id-prefix [*ldh{61} id-prefix]; max 63 chars
                    // id-prefix: alpha / digit
                    // ldh: alpha / digit / dash

                    // Match TLD against known list
                    tld = (String) tldMatcher.group(1).toLowerCase().trim();
                    if (checkTld == true) {
                        boolean foundTld = false;
                        for (int i = 0; i < validTlds.length; i++) {
                            if (tld.equals(validTlds[i])) {
                                foundTld = true;
                            }
                        }

                        if (foundTld == false) {
                            status = false;
                            addMessage("hostname.UnknownTld");
                            break dowhile;
                        }
                    }

                    /**
                     * Match against IDN hostnames
                     * Note: Keep label regex short to avoid issues with long patterns when matching IDN hostnames
                     */
                    List<String> regexChars = getIdnRegexChars();

                    // Check each hostname part
                    int check = 0;
                    for (String domainPart : domainParts) {
                        // Decode Punycode domainnames to IDN
                        if (domainPart.indexOf("xn--") == 0) {
                            domainPart = decodePunycode(domainPart.substring(4));
                        }

                        // Check dash (-) does not start, end or appear in 3rd and 4th positions
                        if (domainPart.indexOf("-") == 0
                                || (domainPart.length() > 2 && domainPart.indexOf("-", 2) == 2 && domainPart.indexOf("-", 3) == 3)
                                || (domainPart.indexOf("-") == (domainPart.length() - 1))) {
                            status = false;
                            addMessage("hostname.DashCharacter");
                            break dowhile;
                        }

                        // Check each domain part
                        boolean checked = false;

                        for (int key = 0; key < regexChars.size(); key++) {
                            String regexChar = regexChars.get(key);
                            Pattern regex = Pattern.compile(regexChar);
                            Matcher regexMatcher = regex.matcher(domainPart);
                            status = regexMatcher.find();
                            if (status) {
                                int length = 63;

                                if (idnLength.containsKey(tld.toUpperCase())
                                        && idnLength.get(tld.toUpperCase()).containsKey(key)) {
                                    length = idnLength.get(tld.toUpperCase()).get(key);
                                }

                                int utf8Length;
                                try {
                                    utf8Length = domainPart.getBytes("UTF8").length;
                                    if (utf8Length > length) {
                                        addMessage("hostname.InvalidHostname");
                                    } else {
                                        checked = true;
                                        break;
                                    }
                                } catch (UnsupportedEncodingException ex) {
                                    Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex);
                                }


                            }
                        }


                        if (checked) {
                            ++check;
                        }
                    }

                    // If one of the labels doesn't match, the hostname is invalid
                    if (check != domainParts.length) {
                        status = false;
                        addMessage("hostname.InvalidHostnameSchema");

                    }
                } else {
                    // Hostname not long enough
                    status = false;
                    addMessage("hostname.UndecipherableTld");
                }

            } while (false);

            if (status == true && allowDNS) {
                result = true;
            }

        } else if (allowDNS == true) {
            addMessage("hostname.InvalidHostname");
            throw new ValidatorException(messages);
        }

        // Check input against local network name schema;
        Pattern regexLocal = Pattern.compile("^(([a-zA-Z0-9\\x2d]{1,63}\\x2e)*[a-zA-Z0-9\\x2d]{1,63}){1,254}$", Pattern.CASE_INSENSITIVE);
        boolean checkLocal = regexLocal.matcher(hostName).find();
        if (allowLocal && !status) {
            if (checkLocal) {
                result = true;
            } else {
                // If the input does not pass as a local network name, add a message
                result = false;
                addMessage("hostname.InvalidLocalName");
            }
        }


        // If local network names are not allowed, add a message
        if (checkLocal && !allowLocal && !status) {
            result = false;
            addMessage("hostname.LocalNameNotAllowed");
        }

        if (result == false) {
            throw new ValidatorException(messages);
        }

    }

    private void addMessage(String msg) {
        String bundlMsg = bundle.getString(msg);
        messages.add(new FacesMessage(FacesMessage.SEVERITY_ERROR, bundlMsg, bundlMsg));
    }

    /**
     * Returns a list of regex patterns for the matched TLD
     * @param tld
     * @return 
     */
    private List<String> getIdnRegexChars() {
        List<String> regexChars = new ArrayList<String>();
        regexChars.add("^[a-z0-9\\x2d]{1,63}$");
        Document doc = null;
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(true);

        try {
            InputStream validIdns = getClass().getClassLoader().getResourceAsStream("com/myapp/resources/validIDNs_1.xml");
            DocumentBuilder builder = factory.newDocumentBuilder();
            doc = builder.parse(validIdns);
            doc.getDocumentElement().normalize();
        } catch (SAXException ex) {
            Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex);
        } catch (IOException ex) {
            Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex);
        } catch (ParserConfigurationException ex) {
            Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex);
        }

        // prepare XPath
        XPath xpath = XPathFactory.newInstance().newXPath();

        NodeList nodes = null;
        String xpathRoute = "//idn[tld=\'" + tld.toUpperCase() + "\']/pattern/text()";

        try {
            XPathExpression expr;
            expr = xpath.compile(xpathRoute);
            Object res = expr.evaluate(doc, XPathConstants.NODESET);
            nodes = (NodeList) res;
        } catch (XPathExpressionException ex) {
            Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex);
        }


        for (int i = 0; i < nodes.getLength(); i++) {
            regexChars.add(nodes.item(i).getNodeValue());
        }

        return regexChars;
    }

    /**
     * Decode Punycode string
     * @param encoded
     * @return 
         */
    private String decodePunycode(String encoded) {
        Pattern regex = Pattern.compile("([^a-z0-9\\x2d]{1,10})", Pattern.CASE_INSENSITIVE);
        Matcher matcher = regex.matcher(encoded);
        boolean found = matcher.find();

        if (encoded.isEmpty() || found) {
            // no punycode encoded string, return as is
            addMessage("hostname.CannotDecodePunycode");
            throw new ValidatorException(messages);
        }

        int separator = encoded.lastIndexOf("-");
            List<Integer> decoded = new ArrayList<Integer>();
        if (separator > 0) {
            for (int x = 0; x < separator; ++x) {
                decoded.add((int) encoded.charAt(x));
            }
        } else {
            addMessage("hostname.CannotDecodePunycode");
            throw new ValidatorException(messages);
        }

        int lengthd = decoded.size();
        int lengthe = encoded.length();

        // decoding
        boolean init = true;
        int base = 72;
        int index = 0;
        int ch = 0x80;

        int indexeStart = (separator == 1) ? (separator + 1) : 0;
        for (int indexe = indexeStart; indexe < lengthe; ++lengthd) {
            int oldIndex = index;
            int pos = 1;
            for (int key = 36; true; key += 36) {
                int hex = (int) encoded.charAt(indexe++);
                int digit = (hex - 48 < 10) ? hex - 22
                        : ((hex - 65 < 26) ? hex - 65
                        : ((hex - 97 < 26) ? hex - 97
                        : 36));

                index += digit * pos;
                int tag = (key <= base) ? 1 : ((key >= base + 26) ? 26 : (key - base));
                if (digit < tag) {
                    break;
                }
                pos = (int) (pos * (36 - tag));
            }
            int delta = (int) (init ? ((index - oldIndex) / 700) : ((index - oldIndex) / 2));
            delta += (int) (delta / (lengthd + 1));
            int key;
            for (key = 0; delta > 910; key += 36) {
                delta = (int) (delta / 35);
            }
            base = (int) (key + 36 * delta / (delta + 38));
            init = false;
            ch += (int) (index / (lengthd + 1));
            index %= (lengthd + 1);
            if (lengthd > 0) {
                for (int i = lengthd; i > index; i--) {
                    decoded.set(i, decoded.get(i - 1));
                }
            }

            decoded.set(index++, ch);
        }

        // convert decoded ucs4 to utf8 string
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < decoded.size(); i++) {
            int value = decoded.get(i);
            if (value < 128) {
                sb.append((char) value);
            } else if (value < (1 << 11)) {
                sb.append((char) (192 + (value >> 6)));
                sb.append((char) (128 + (value & 63)));
            } else if (value < (1 << 16)) {
                sb.append((char) (224 + (value >> 12)));
                sb.append((char) (128 + ((value >> 6) & 63)));
                sb.append((char) (128 + (value & 63)));
            } else if (value < (1 << 21)) {
                sb.append((char) (240 + (value >> 18)));
                sb.append((char) (128 + ((value >> 12) & 63)));
                sb.append((char) (128 + ((value >> 6) & 63)));
                sb.append((char) (128 + (value & 63)));
            } else {
                addMessage("hostname.CannotDecodePunycode");
                throw new ValidatorException(messages);
            }
        }

        return sb.toString();

    }

    /**
     * Eliminates empty values from input array
     * @param data
     * @return 
     */
    private String[] verifyArray(String[] data) {
        List<String> result = new ArrayList<String>();
        for (String s : data) {
            if (!s.equals("")) {
                result.add(s);
            }
        }

        return result.toArray(new String[result.size()]);
    }
}

And a validIDNs.xml with regex patterns for the different tlds (too big to include:)

<idnlist>
    <idn>
        <tld>AC</tld>
        <pattern>^[\u002d0-9a-zà-öø-ÿaaaccccddeeeeggghhiijklll?lnnn?oœrrrsssštttuuuuuwyzzž]{1,63}$</pattern>
    </idn>
    <idn>
        <tld>AR</tld>
        <pattern>^[\u002d0-9a-zà-ãç-êìíñ-õü]{1,63}$</pattern>
    </idn>
    <idn>
        <tld>AS</tld>
        <pattern>/^[\u002d0-9a-zà-öø-ÿaaaccccddeeeeegggghhiiiiijk?llllnnn?oooœrrrsssštttuuuuuuwyzz]{1,63}$</pattern>
    </idn>
    <idn>
        <tld>AT</tld>
        <pattern>/^[\u002d0-9a-zà-öø-ÿœšž]{1,63}$</pattern>
    </idn>
    <idn>
        <tld>BIZ</tld>
        <pattern>^[\u002d0-9a-zäåæéöøü]{1,63}$</pattern>
        <pattern>^[\u002d0-9a-záéíñóúü]{1,63}$</pattern>
        <pattern>^[\u002d0-9a-záéíóöúüou]{1,63}$</pattern>
    </id>
</idlist>

Can I mask an input text in a bat file?

I wrote an open source program called editenv that replaces my older editv32/editv64 utilities:

https://github.com/Bill-Stewart/editenv

The --maskinput (-m) option[*] lets you hide (mask) the typed input and has a configurable character (default character is *); e.g.:

editenv -m -p "Password: " PWD

The --prompt (-p) option lets you specify an input prompt. The above will display a Password: prompt and wait for you to enter something. Typed characters will appear as *. Pressing Ctrl+C will end the program with an exit code of 1223.

Download is here:

https://github.com/Bill-Stewart/editenv/releases

[*] Note that the --maskinput (-m) option is not secure -- the entered string is entered as plain-text in the environment. This feature is for convenience only.

Node.js - use of module.exports as a constructor

At the end, Node is about Javascript. JS has several way to accomplished something, is the same thing to get an "constructor", the important thing is to return a function.

This way actually you are creating a new function, as we created using JS on Web Browser environment for example.

Personally i prefer the prototype approach, as Sukima suggested on this post: Node.js - use of module.exports as a constructor

Setting active profile and config location from command line in spring boot

you can use the following command line:

java -jar -Dspring.profiles.active=[yourProfileName] target/[yourJar].jar

Javascript-Setting background image of a DIV via a function and function parameter

If you are looking for a direct approach and using a local File in that case. Try

<div
style={{ background-image: 'url(' + Image + ')', background-size: 'auto' }}
/>

This is the case of JS with inline styling where Image is a local file that you must have imported with a path.

How to fix Error: laravel.log could not be opened?

It also may be SELinux. (Centos, RedHat)

Determine status of SElinux on terminal:

$ sestatus

If status is enabled, write command to disable SElinux

$ setenforce Permissive

Or you may execute this command

$ sudo setenforce 0

ERROR 1049 (42000): Unknown database

Very simple solution. Just rename your database and configure your new database name in your project.

The problem is the when you import your database, you got any errors and then the database will be corrupted. The log files will have the corrupted database name. You can rename your database easily using phpmyadmin for mysql.

phpmyadmin -> operations -> Rename database to

Switch case with fallthrough?

If the values are integer then you can use [2-3] or you can use [5,7,8] for non continuous values.

#!/bin/bash
while [ $# -gt 0 ];
do
    case $1 in
    1)
        echo "one"
        ;;
    [2-3])
        echo "two or three"
        ;;
    [4-6])
        echo "four to six"
        ;;
    [7,9])
        echo "seven or nine"
        ;;
    *)
        echo "others"
        ;;
    esac
    shift
done

If the values are string then you can use |.

#!/bin/bash
while [ $# -gt 0 ];
do
    case $1 in
    "one")
        echo "one"
        ;;
    "two" | "three")
        echo "two or three"
        ;;
    *)
        echo "others"
        ;;
    esac
    shift
done

How to style readonly attribute with CSS?

capitalize the first letter of Only

_x000D_
_x000D_ 
input[readOnly] {_x000D_
      background: red !important;_x000D_
    }
_x000D_ 
<input type="text" name="country" value="China" readonly="readonly" />
_x000D_
_x000D_
_x000D_

Finding all possible combinations of numbers to reach a given sum

I was doing something similar for a scala assignment. Thought of posting my solution here:

 def countChange(money: Int, coins: List[Int]): Int = {
      def getCount(money: Int, remainingCoins: List[Int]): Int = {
        if(money == 0 ) 1
        else if(money < 0 || remainingCoins.isEmpty) 0
        else
          getCount(money, remainingCoins.tail) +
            getCount(money - remainingCoins.head, remainingCoins)
      }
      if(money == 0 || coins.isEmpty) 0
      else getCount(money, coins)
    }

alter the size of column in table containing data

Case 1 : Yes, this works fine.

Case 2 : This will fail with the error ORA-01441 : cannot decrease column length because some value is too big.

Share and enjoy.

How and when to use ‘async’ and ‘await’

See this fiddle https://dotnetfiddle.net/VhZdLU (and improve it if possible) for running a simple console application which shows usages of Task, Task.WaitAll(), async and await operators in the same program.

This fiddle should clear your execution cycle concept.

Here is the sample code

using System;
using System.Threading.Tasks;

public class Program
{
    public static void Main()
    {               
        var a = MyMethodAsync(); //Task started for Execution and immediately goes to Line 19 of the code. Cursor will come back as soon as await operator is met       
        Console.WriteLine("Cursor Moved to Next Line Without Waiting for MyMethodAsync() completion");
        Console.WriteLine("Now Waiting for Task to be Finished");       
        Task.WaitAll(a); //Now Waiting      
        Console.WriteLine("Exiting CommandLine");       
    }

    public static async Task MyMethodAsync()
    {
        Task<int> longRunningTask = LongRunningOperation();
        // independent work which doesn't need the result of LongRunningOperationAsync can be done here
        Console.WriteLine("Independent Works of now executes in MyMethodAsync()");
        //and now we call await on the task 
        int result = await longRunningTask;
        //use the result 
        Console.WriteLine("Result of LongRunningOperation() is " + result);
    }

    public static async Task<int> LongRunningOperation() // assume we return an int from this long running operation 
    {
        Console.WriteLine("LongRunningOperation() Started");
        await Task.Delay(2000); // 2 second delay
        Console.WriteLine("LongRunningOperation() Finished after 2 Seconds");
        return 1;
    }   

}

Trace coming from Output Window: enter image description here

How to convert all text to lowercase in Vim

use ggguG

gg: goes to the first line.

gu: change to lowercase.

G: goes to the last line.

ASP.NET Identity reset password

Create method in UserManager<TUser, TKey>

public Task<IdentityResult> ChangePassword(int userId, string newPassword)
{
     var user = Users.FirstOrDefault(u => u.Id == userId);
     if (user == null)
          return new Task<IdentityResult>(() => IdentityResult.Failed());

     var store = Store as IUserPasswordStore<User, int>;
     return base.UpdatePassword(store, user, newPassword);
}

How to increase icons size on Android Home Screen?

If you want to change settings in the launcher, change icon size, or grid size just hold down on an empty part of your home screen. Tap the three Dots and there you go.

From https://forums.oneplus.net/threads/how-to-change-icon-and-grid-size-trebuchet-settings.84820/

When configuring the phone for first time I saw something about a grid somewhere, but couldn't find it again. Luckily I found the answer on the link above.

Meaning of *& and **& in C++

An int* is a pointer to an int, so int*& must be a reference to a pointer to an int. Similarly, int** is a pointer to a pointer to an int, so int**& must be a reference to a pointer to a pointer to an int.

How to animate button in android?

 
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.Transformation;

public class HeightAnimation extends Animation {
    protected final int originalHeight;
    protected final View view;
    protected float perValue;

    public HeightAnimation(View view, int fromHeight, int toHeight) {
        this.view = view;
        this.originalHeight = fromHeight;
        this.perValue = (toHeight - fromHeight);
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        view.getLayoutParams().height = (int) (originalHeight + perValue * interpolatedTime);
        view.requestLayout();
    }

    @Override
    public boolean willChangeBounds() {
        return true;
    }
}

uss to:

HeightAnimation heightAnim = new HeightAnimation(view, view.getHeight(), viewPager.getHeight() - otherView.getHeight());
heightAnim.setDuration(1000);
view.startAnimation(heightAnim);

What is the difference between a .cpp file and a .h file?

The .cpp file is the compilation unit : it's the real source code file that will be compiled (in C++).

The .h (header) files are files that will be virtually copy/pasted in the .cpp files where the #include precompiler instruction appears. Once the headers code is inserted in the .cpp code, the compilation of the .cpp can start.

g++ ld: symbol(s) not found for architecture x86_64

finally solved my problem.

I created a new project in XCode with the sources and changed the C++ Standard Library from the default libc++ to libstdc++ as in this and this.

Select from multiple tables without a join?

You should try this

 SELECT t1.*,t2.* FROM t1,t2

OWIN Security - How to Implement OAuth2 Refresh Tokens

Just implemented my OWIN Service with Bearer (called access_token in the following) and Refresh Tokens. My insight into this is that you can use different flows. So it depends on the flow you want to use how you set your access_token and refresh_token expiration times.

I will describe two flows A and B in the follwing (I suggest what you want to have is flow B):

A) expiration time of access_token and refresh_token are the same as it is per default 1200 seconds or 20 minutes. This flow needs your client first to send client_id and client_secret with login data to get an access_token, refresh_token and expiration_time. With the refresh_token it is now possible to get a new access_token for 20 minutes (or whatever you set the AccessTokenExpireTimeSpan in the OAuthAuthorizationServerOptions to). For the reason that the expiration time of access_token and refresh_token are the same, your client is responsible to get a new access_token before the expiration time! E.g. your client could send a refresh POST call to your token endpoint with the body (remark: you should use https in production) 

grant_type=refresh_token&client_id=xxxxxx&refresh_token=xxxxxxxx-xxxx-xxxx-xxxx-xxxxx

to get a new token after e.g. 19 minutes to prevent the tokens from expiration.

B) in this flow you want to have a short term expiration for your access_token and a long term expiration for your refresh_token. Lets assume for test purpose you set the access_token to expire in 10 seconds (AccessTokenExpireTimeSpan = TimeSpan.FromSeconds(10)) and the refresh_token to 5 Minutes. Now it comes to the interesting part setting the expiration time of refresh_token: You do this in your createAsync function in SimpleRefreshTokenProvider class like this:

var guid = Guid.NewGuid().ToString();


        //copy properties and set the desired lifetime of refresh token
        var refreshTokenProperties = new AuthenticationProperties(context.Ticket.Properties.Dictionary)
        {
            IssuedUtc = context.Ticket.Properties.IssuedUtc,
            ExpiresUtc = DateTime.UtcNow.AddMinutes(5) //SET DATETIME to 5 Minutes
            //ExpiresUtc = DateTime.UtcNow.AddMonths(3) 
        };
        /*CREATE A NEW TICKET WITH EXPIRATION TIME OF 5 MINUTES 
         *INCLUDING THE VALUES OF THE CONTEXT TICKET: SO ALL WE 
         *DO HERE IS TO ADD THE PROPERTIES IssuedUtc and 
         *ExpiredUtc to the TICKET*/
        var refreshTokenTicket = new AuthenticationTicket(context.Ticket.Identity, refreshTokenProperties);

        //saving the new refreshTokenTicket to a local var of Type ConcurrentDictionary<string,AuthenticationTicket>
        // consider storing only the hash of the handle
        RefreshTokens.TryAdd(guid, refreshTokenTicket);            
        context.SetToken(guid);

Now your client is able to send a POST call with a refresh_token to your token endpoint when the access_token is expired. The body part of the call may look like this: grant_type=refresh_token&client_id=xxxxxx&refresh_token=xxxxxxxx-xxxx-xxxx-xxxx-xx

One important thing is that you may want to use this code not only in your CreateAsync function but also in your Create function. So you should consider to use your own function (e.g. called CreateTokenInternal) for the above code. Here you can find implementations of different flows including refresh_token flow(but without setting the expiration time of the refresh_token)

Here is one sample implementation of IAuthenticationTokenProvider on github (with setting the expiration time of the refresh_token)

I am sorry that I can't help out with further materials than the OAuth Specs and the Microsoft API Documentation. I would post the links here but my reputation doesn't let me post more than 2 links....

I hope this may help some others to spare time when trying to implement OAuth2.0 with refresh_token expiration time different to access_token expiration time. I couldn't find an example implementation on the web (except the one of thinktecture linked above) and it took me some hours of investigation until it worked for me.

New info: In my case I have two different possibilities to receive tokens. One is to receive a valid access_token. There I have to send a POST call with a String body in format application/x-www-form-urlencoded with the following data 

client_id=YOURCLIENTID&grant_type=password&username=YOURUSERNAME&password=YOURPASSWORD

Second is if access_token is not valid anymore we can try the refresh_token by sending a POST call with a String body in format application/x-www-form-urlencoded with the following data grant_type=refresh_token&client_id=YOURCLIENTID&refresh_token=YOURREFRESHTOKENGUID

How to show DatePickerDialog on Button click?

 
    final Calendar newCalendar = Calendar.getInstance();
    final DatePickerDialog  StartTime = new DatePickerDialog(this, new DatePickerDialog.OnDateSetListener() {
                public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
                    Calendar newDate = Calendar.getInstance();
                    newDate.set(year, monthOfYear, dayOfMonth);
                    activitydate.setText(dateFormatter.format(newDate.getTime()));
                }
    
            }, newCalendar.get(Calendar.YEAR), newCalendar.get(Calendar.MONTH), newCalendar.get(Calendar.DAY_OF_MONTH));
    
      btn_checkin.setOnClickListener(new View.OnClickListener() {
@Override   public void onClick(View v) {
         StartTime.show():    
     });

find filenames NOT ending in specific extensions on Unix?

Linux/OS X:

Starting from the current directory, recursively find all files ending in .dll or .exe

find . -type f | grep -P "\.dll$|\.exe$"

Starting from the current directory, recursively find all files that DON'T end in .dll or .exe

find . -type f | grep -vP "\.dll$|\.exe$"

Notes:

(1) The P option in grep indicates that we are using the Perl style to write our regular expressions to be used in conjunction with the grep command. For the purpose of excecuting the grep command in conjunction with regular expressions, I find that the Perl style is the most powerful style around.

(2) The v option in grep instructs the shell to exclude any file that satisfies the regular expression

(3) The $ character at the end of say ".dll$" is a delimiter control character that tells the shell that the filename string ends with ".dll"

Correct way to initialize HashMap and can HashMap hold different value types?

It really depends on what kind of type safety you need. The non-generic way of doing it is best done as:

 Map x = new HashMap();

Note that x is typed as a Map. this makes it much easier to change implementations (to a TreeMap or a LinkedHashMap) in the future.

You can use generics to ensure a certain level of type safety:

Map<String, Object> x = new HashMap<String, Object>();

In Java 7 and later you can do

Map<String, Object> x = new HashMap<>();

The above, while more verbose, avoids compiler warnings. In this case the content of the HashMap can be any Object, so that can be Integer, int[], etc. which is what you are doing.

If you are still using Java 6, Guava Libraries (although it is easy enough to do yourself) has a method called newHashMap() which avoids the need to duplicate the generic typing information when you do a new. It infers the type from the variable declaration (this is a Java feature not available on constructors prior to Java 7).

By the way, when you add an int or other primitive, Java is autoboxing it. That means that the code is equivalent to:

 x.put("one", Integer.valueOf(1));

You can certainly put a HashMap as a value in another HashMap, but I think there are issues if you do it recursively (that is put the HashMap as a value in itself).

How do I make an editable DIV look like a text field?

If you use bootstrap just add form-control class. For example:

class="form-control"

CSS:Defining Styles for input elements inside a div

When you say "called" I'm going to assume you mean an ID tag.

To make it cross-brower, I wouldn't suggest using the CSS3 [], although it is an option. This being said, give each of your textboxes a class like "tb" and the radio button "rb".

Then:

#divContainer .tb { width: 150px }
#divContainer .rb { width: 20px }

This assumes you are using the same classes elsewhere, if not, this will suffice:

.tb { width: 150px }
.rb { width: 20px }

As @David mentioned, to access anything within the division itself:

#divContainer [element] { ... }

Where [element] is whatever HTML element you need.

Is it still valid to use IE=edge,chrome=1?

 
<head>
<meta http-equiv='X-UA-Compatible' content='IE=edge'>

worked for me, to force IE to "snap out of compatibility mode" (so to speak), BUT that meta statement must appear IMMEDIATELY after the <head>, or it won't work!

Recommended way to save uploaded files in a servlet application

Store it anywhere in an accessible location except of the IDE's project folder aka the server's deploy folder, for reasons mentioned in the answer to Uploaded image only available after refreshing the page:

  1. Changes in the IDE's project folder does not immediately get reflected in the server's work folder. There's kind of a background job in the IDE which takes care that the server's work folder get synced with last updates (this is in IDE terms called "publishing"). This is the main cause of the problem you're seeing.

  2. In real world code there are circumstances where storing uploaded files in the webapp's deploy folder will not work at all. Some servers do (either by default or by configuration) not expand the deployed WAR file into the local disk file system, but instead fully in the memory. You can't create new files in the memory without basically editing the deployed WAR file and redeploying it.

  3. Even when the server expands the deployed WAR file into the local disk file system, all newly created files will get lost on a redeploy or even a simple restart, simply because those new files are not part of the original WAR file.

It really doesn't matter to me or anyone else where exactly on the local disk file system it will be saved, as long as you do not ever use getRealPath() method. Using that method is in any case alarming.

The path to the storage location can in turn be definied in many ways. You have to do it all by yourself. Perhaps this is where your confusion is caused because you somehow expected that the server does that all automagically. Please note that @MultipartConfig(location) does not specify the final upload destination, but the temporary storage location for the case file size exceeds memory storage threshold.

So, the path to the final storage location can be definied in either of the following ways:

  • Hardcoded:

      File uploads = new File("/path/to/uploads");

  • Environment variable via SET UPLOAD_LOCATION=/path/to/uploads:

      File uploads = new File(System.getenv("UPLOAD_LOCATION"));

  • VM argument during server startup via -Dupload.location="/path/to/uploads":

      File uploads = new File(System.getProperty("upload.location"));

  • *.properties file entry as upload.location=/path/to/uploads:

      File uploads = new File(properties.getProperty("upload.location"));

  • web.xml <context-param> with name upload.location and value /path/to/uploads:

      File uploads = new File(getServletContext().getInitParameter("upload.location"));

  • If any, use the server-provided location, e.g. in JBoss AS/WildFly:

      File uploads = new File(System.getProperty("jboss.server.data.dir"), "uploads");

Either way, you can easily reference and save the file as follows:

File file = new File(uploads, "somefilename.ext");

try (InputStream input = part.getInputStream()) {
    Files.copy(input, file.toPath());
}

Or, when you want to autogenerate an unique file name to prevent users from overwriting existing files with coincidentally the same name:

File file = File.createTempFile("somefilename-", ".ext", uploads);

try (InputStream input = part.getInputStream()) {
    Files.copy(input, file.toPath(), StandardCopyOption.REPLACE_EXISTING);
}

How to obtain part in JSP/Servlet is answered in How to upload files to server using JSP/Servlet? and how to obtain part in JSF is answered in How to upload file using JSF 2.2 <h:inputFile>? Where is the saved File?

Note: do not use Part#write() as it interprets the path relative to the temporary storage location defined in @MultipartConfig(location).

See also:

"unary operator expected" error in Bash if condition

Try assigning a value to $aug1 before use it in if[] statements; the error message will disappear afterwards.

Python List & for-each access (Find/Replace in built-in list)

Answering this has been good, as the comments have led to an improvement in my own understanding of Python variables.

As noted in the comments, when you loop over a list with something like for member in my_list the member variable is bound to each successive list element. However, re-assigning that variable within the loop doesn't directly affect the list itself. For example, this code won't change the list:

my_list = [1,2,3]
for member in my_list:
    member = 42
print my_list

Output:

[1, 2, 3]

If you want to change a list containing immutable types, you need to do something like:

my_list = [1,2,3]
for ndx, member in enumerate(my_list):
    my_list[ndx] += 42
print my_list

Output:

[43, 44, 45]

If your list contains mutable objects, you can modify the current member object directly:

class C:
    def __init__(self, n):
        self.num = n
    def __repr__(self):
        return str(self.num)

my_list = [C(i) for i in xrange(3)]
for member in my_list:
    member.num += 42
print my_list

[42, 43, 44]

Note that you are still not changing the list, simply modifying the objects in the list.

You might benefit from reading Naming and Binding.

Can I use Objective-C blocks as properties?

 
@property (nonatomic, copy) void (^simpleBlock)(void);
@property (nonatomic, copy) BOOL (^blockWithParamter)(NSString *input);

If you are going to be repeating the same block in several places use a type def

typedef void(^MyCompletionBlock)(BOOL success, NSError *error);
@property (nonatomic) MyCompletionBlock completion;

How to sort List<Integer>?

Use Collections class API to sort.

Collections.sort(list);

OSError: [WinError 193] %1 is not a valid Win32 application

For me issue got resolved after following steps :

  1. Installing python 32 bit version on windows.
  2. Add newly installed python and it's script folder(where pip resides in environment variable)

Issue comes when any application you want to run needs python 32 bit variants and you have 64 bit variant

Note : Once you install python 32 bit variant,dont forget to install all required packages using pip of this new python 32 bit variant

"for loop" with two variables?

If you want the effect of a nested for loop, use:

import itertools
for i, j in itertools.product(range(x), range(y)):
    # Stuff...

If you just want to loop simultaneously, use:

for i, j in zip(range(x), range(y)):
    # Stuff...

Note that if x and y are not the same length, zip will truncate to the shortest list. As @abarnert pointed out, if you don't want to truncate to the shortest list, you could use itertools.zip_longest.

UPDATE

Based on the request for "a function that will read lists "t1" and "t2" and return all elements that are identical", I don't think the OP wants zip or product. I think they want a set:

def equal_elements(t1, t2):
    return list(set(t1).intersection(set(t2)))
    # You could also do
    # return list(set(t1) & set(t2))

The intersection method of a set will return all the elements common to it and another set (Note that if your lists contains other lists, you might want to convert the inner lists to tuples first so that they are hashable; otherwise the call to set will fail.). The list function then turns the set back into a list.

UPDATE 2

OR, the OP might want elements that are identical in the same position in the lists. In this case, zip would be most appropriate, and the fact that it truncates to the shortest list is what you would want (since it is impossible for there to be the same element at index 9 when one of the lists is only 5 elements long). If that is what you want, go with this:

def equal_elements(t1, t2):
    return [x for x, y in zip(t1, t2) if x == y]

This will return a list containing only the elements that are the same and in the same position in the lists.

Difference between @Before, @BeforeClass, @BeforeEach and @BeforeAll

The basic difference between all these annotations is as follows -

  1. @BeforeEach - Use to run a common code before( eg setUp) each test method execution. analogous to JUnit 4’s @Before.
  2. @AfterEach - Use to run a common code after( eg tearDown) each test method execution. analogous to JUnit 4’s @After.
  3. @BeforeAll - Use to run once per class before any test execution. analogous to JUnit 4’s @BeforeClass.
  4. @AfterAll - Use to run once per class after all test are executed. analogous to JUnit 4’s @AfterClass.

All these annotations along with the usage is defined on Codingeek - Junit5 Test Lifecycle

How does #include <bits/stdc++.h> work in C++?

Unfortunately that approach is not portable C++ (so far).

All standard names are in namespace std and moreover you cannot know which names are NOT defined by including and header (in other words it's perfectly legal for an implementation to declare the name std::string directly or indirectly when using #include <vector>).

Despite this however you are required by the language to know and tell the compiler which standard header includes which part of the standard library. This is a source of portability bugs because if you forget for example #include <map> but use std::map it's possible that the program compiles anyway silently and without warnings on a specific version of a specific compiler, and you may get errors only later when porting to another compiler or version.

In my opinion there are no valid technical excuses because this is necessary for the general user: the compiler binary could have all standard namespace built in and this could actually increase the performance even more than precompiled headers (e.g. using perfect hashing for lookups, removing standard headers parsing or loading/demarshalling and so on).

The use of standard headers simplifies the life of who builds compilers or standard libraries and that's all. It's not something to help users.

However this is the way the language is defined and you need to know which header defines which names so plan for some extra neurons to be burnt in pointless configurations to remember that (or try to find and IDE that automatically adds the standard headers you use and removes the ones you don't... a reasonable alternative).

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

Make a

class PassMeByRef { public int theValue; }

then pass a reference to an instance of it. Note that a method that mutates state through its arguments is best avoided, especially in parallel code.

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

There are some options in constructors look, if you don't have dropdownList and you wanna insert CSS class you can use like

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

in this case Country is the name of your dropdown, null is for you aren't passing any generic list from your controller "Choose-Category" is selected item and last one in CSS class if you don't wanna select any default option so simple replace "Choose-Category" with ""

Username and password in command for git push

Yes, you can do

git push https://username:[email protected]/file.git --all

in this case https://username:[email protected]/file.git replace the origin in git push origin --all

To see more options for git push, try git help push

Why am I getting an error "Object literal may only specify known properties"?

As of TypeScript 1.6, properties in object literals that do not have a corresponding property in the type they're being assigned to are flagged as errors.

Usually this error means you have a bug (typically a typo) in your code, or in the definition file. The right fix in this case would be to fix the typo. In the question, the property callbackOnLoactionHash is incorrect and should have been callbackOnLocationHash (note the mis-spelling of "Location").

This change also required some updates in definition files, so you should get the latest version of the .d.ts for any libraries you're using.

Example:

interface TextOptions {
    alignment?: string;
    color?: string;
    padding?: number;
}
function drawText(opts: TextOptions) { ... }
drawText({ align: 'center' }); // Error, no property 'align' in 'TextOptions'

But I meant to do that

There are a few cases where you may have intended to have extra properties in your object. Depending on what you're doing, there are several appropriate fixes

Type-checking only some properties

Sometimes you want to make sure a few things are present and of the correct type, but intend to have extra properties for whatever reason. Type assertions (<T>v or v as T) do not check for extra properties, so you can use them in place of a type annotation:

interface Options {
    x?: string;
    y?: number;
}

// Error, no property 'z' in 'Options'
let q1: Options = { x: 'foo', y: 32, z: 100 };
// OK
let q2 = { x: 'foo', y: 32, z: 100 } as Options;
// Still an error (good):
let q3 = { x: 100, y: 32, z: 100 } as Options;

These properties and maybe more

Some APIs take an object and dynamically iterate over its keys, but have 'special' keys that need to be of a certain type. Adding a string indexer to the type will disable extra property checking

Before

interface Model {
  name: string;
}
function createModel(x: Model) { ... }

// Error
createModel({name: 'hello', length: 100});

After

interface Model {
  name: string;
  [others: string]: any;
}
function createModel(x: Model) { ... }

// OK
createModel({name: 'hello', length: 100});

This is a dog or a cat or a horse, not sure yet

interface Animal { move; }
interface Dog extends Animal { woof; }
interface Cat extends Animal { meow; }
interface Horse extends Animal { neigh; }

let x: Animal;
if(...) {
  x = { move: 'doggy paddle', woof: 'bark' };
} else if(...) {
  x = { move: 'catwalk', meow: 'mrar' };
} else {
  x = { move: 'gallop', neigh: 'wilbur' };
}

Two good solutions come to mind here

Specify a closed set for x

// Removes all errors
let x: Dog|Cat|Horse;

or Type assert each thing

// For each initialization
  x = { move: 'doggy paddle', woof: 'bark' } as Dog;

This type is sometimes open and sometimes not

A clean solution to the "data model" problem using intersection types:

interface DataModelOptions {
  name?: string;
  id?: number;
}
interface UserProperties {
  [key: string]: any;
}
function createDataModel(model: DataModelOptions & UserProperties) {
 /* ... */
}
// findDataModel can only look up by name or id
function findDataModel(model: DataModelOptions) {
 /* ... */
}
// OK
createDataModel({name: 'my model', favoriteAnimal: 'cat' });
// Error, 'ID' is not correct (should be 'id')
findDataModel({ ID: 32 });

See also https://github.com/Microsoft/TypeScript/issues/3755

Using git commit -a with vim

Instead of trying to learn vim, use a different easier editor (like nano, for example). As much as I like vim, I do not think using it in this case is the solution. It takes dedication and time to master it.

git config core.editor "nano"

Click a button programmatically

Best implementation depends of what you are attempting to do exactly. Nadeem_MK gives you a valid one. Know you can also:

  1. raise the Button2_Click event using PerformClick() method:

    Private Sub Button1_Click(sender As Object, e As System.EventArgs) Handles Button1.Click
    'do stuff
    Me.Button2.PerformClick()
End Sub

  2. attach the same handler to many buttons:

    Private Sub Button1_Click(sender As Object, e As System.EventArgs) _
    Handles Button1.Click, Button2.Click
    'do stuff
End Sub

  3. call the Button2_Click method using the same arguments than Button1_Click(...) method (IF you need to know which is the sender, for example) :

    Private Sub Button1_Click(sender As Object, e As System.EventArgs) Handles Button1.Click
    'do stuff
     Button2_Click(sender, e)
End Sub

Generate Java classes from .XSD files...?

Isn't JAXB's XJC is a possible answer to this? I'm trying to achieve the same thing. Still in the "trying" phase though. Came across XJC, so thought of sharing.

Initializing a static std::map<int, int> in C++

Using C++11:

#include <map>
using namespace std;

map<int, char> m = {{1, 'a'}, {3, 'b'}, {5, 'c'}, {7, 'd'}};

Using Boost.Assign:

#include <map>
#include "boost/assign.hpp"
using namespace std;
using namespace boost::assign;

map<int, char> m = map_list_of (1, 'a') (3, 'b') (5, 'c') (7, 'd');

On - window.location.hash - Change?

Another great implementation is jQuery History which will use the native onhashchange event if it is supported by the browser, if not it will use an iframe or interval appropriately for the browser to ensure all the expected functionality is successfully emulated. It also provides a nice interface to bind to certain states.

Another project worth noting as well is jQuery Ajaxy which is pretty much an extension for jQuery History to add ajax to the mix. As when you start using ajax with hashes it get's quite complicated!

disable viewport zooming iOS 10+ safari?

Check for scale factor in touchove event then prevent touch event.

document.addEventListener('touchmove', function(event) {
    event = event.originalEvent || event;
    if(event.scale > 1) {
        event.preventDefault();
    }
}, false);

create table with sequence.nextval in oracle

In Oracle 12c you can also declare an identity column

CREATE TABLE identity_test_tab (
  id          NUMBER GENERATED BY DEFAULT ON NULL AS IDENTITY,
  description VARCHAR2(30)
);

examples & performance tests here ... where, is shorts, the conclusion is that the direct use of the sequence or the new identity column are much faster than the triggers.

How can I change the image of an ImageView?

Have a look at the ImageView API. There are several setImage* methods. Which one to use depends on the image you provide. If you have the image as resource (e.g. file res/drawable/my_image.png)

ImageView img = new ImageView(this);  // or (ImageView) findViewById(R.id.myImageView);
img.setImageResource(R.drawable.my_image);

Simplest/cleanest way to implement a singleton in JavaScript

Singleton:

Ensure a class has only one instance and provides a global point of access to it.

The singleton pattern limits the number of instances of a particular object to just one. This single instance is called the singleton.

  • defines getInstance() which returns the unique instance.
  • responsible for creating and managing the instance object.

The singleton object is implemented as an immediate anonymous function. The function executes immediately by wrapping it in brackets followed by two additional brackets. It is called anonymous because it doesn't have a name.

Sample Program

_x000D_
_x000D_ 
var Singleton = (function () {
    var instance;

    function createInstance() {
        var object = new Object("I am the instance");
        return object;
    }

    return {
        getInstance: function () {
            if (!instance) {
                instance = createInstance();
            }
            return instance;
        }
    };
})();

function run() {

    var instance1 = Singleton.getInstance();
    var instance2 = Singleton.getInstance();

    alert("Same instance? " + (instance1 === instance2));
}

run()
_x000D_
_x000D_
_x000D_

Formatting DataBinder.Eval data

Text='<%# DateTime.Parse(Eval("LastLoginDate").ToString()).ToString("MM/dd/yyyy hh:mm tt") %>'

This works for the format as you want

In log4j, does checking isDebugEnabled before logging improve performance?

I would recommend using Option 2 as de facto for most as it's not super expensive.

Case 1: log.debug("one string")

Case2: log.debug("one string" + "two string" + object.toString + object2.toString)

At the time either of these are called, the parameter string within log.debug (be it CASE 1 or Case2) HAS to be evaluated. That's what everyone means by 'expensive.' If you have a condition before it, 'isDebugEnabled()', these don't have to be evaluated which is where the performance is saved.

Selenium 2.53 not working on Firefox 47

If you're on a Mac do brew install geckodriver and off you go!

Combination of async function + await + setTimeout

The quick one-liner, inline way

 await new Promise(resolve => setTimeout(resolve, 1000));

Python extending with - using super() Python 3 vs Python 2

Another python3 implementation that involves the use of Abstract classes with super(). You should remember that 

super().__init__(name, 10)

has the same effect as 

Person.__init__(self, name, 10)

Remember there's a hidden 'self' in super(), So the same object passes on to the superclass init method and the attributes are added to the object that called it. Hence super()gets translated to Person and then if you include the hidden self, you get the above code frag. 

from abc import ABCMeta, abstractmethod
class Person(metaclass=ABCMeta):
    name = ""
    age = 0

    def __init__(self, personName, personAge):
        self.name = personName
        self.age = personAge

    @abstractmethod
    def showName(self):
        pass

    @abstractmethod
    def showAge(self):
        pass


class Man(Person):

    def __init__(self, name, height):
        self.height = height
        # Person.__init__(self, name, 10)
        super().__init__(name, 10)  # same as Person.__init__(self, name, 10)
        # basically used to call the superclass init . This is used incase you want to call subclass init
        # and then also call superclass's init.
        # Since there's a hidden self in the super's parameters, when it's is called,
        # the superclasses attributes are a part of the same object that was sent out in the super() method

    def showIdentity(self):
        return self.name, self.age, self.height

    def showName(self):
        pass

    def showAge(self):
        pass


a = Man("piyush", "179")
print(a.showIdentity())

How to convert an Object {} to an Array [] of key-value pairs in JavaScript

The best way is to do:

var obj ={"1":5,"2":7,"3":0,"4":0,"5":0,"6":0,"7":0,"8":0,"9":0,"10"??:0,"11":0,"12":0} 
Object.entries(obj);

Calling entries, as shown here, will return [key, value] pairs, as the asker requested.

Alternatively, you could call Object.values(obj), which would return only values.

Regular expression to search multiple strings (Textpad)

To get the lines that contain the texts 8768, 9875 or 2353, use:

^.*(8768|9875|2353).*$

What it means:

^                      from the beginning of the line
.*                     get any character except \n (0 or more times)
(8768|9875|2353)       if the line contains the string '8768' OR '9875' OR '2353'
.*                     and get any character except \n (0 or more times)
$                      until the end of the line

If you do want the literal * char, you'd have to escape it:

^.*(\*8768|\*9875|\*2353).*$

How do I get first element rather than using [0] in jQuery?

You can use the first method:

$('li').first()

http://api.jquery.com/first/

btw I agree with Nick Craver -- use document.getElementById()...

What is @RenderSection in asp.net MVC

If

(1) you have a _Layout.cshtml view like this

<html>
    <body>
        @RenderBody()

    </body>
    <script type="text/javascript" src="~/lib/layout.js"></script>
    @RenderSection("scripts", required: false)
</html>

(2) you have Contacts.cshtml 

@section Scripts{
    <script type="text/javascript" src="~/lib/contacts.js"></script>

}
<div class="row">
    <div class="col-md-6 col-md-offset-3">
        <h2>    Contacts</h2>
    </div>
</div>

(3) you have About.cshtml 

<div class="row">
    <div class="col-md-6 col-md-offset-3">
        <h2>    Contacts</h2>
    </div>
</div>

On you layout page, if required is set to false "@RenderSection("scripts", required: false)", When page renders and user is on about page, the contacts.js doesn't render.

    <html>
        <body><div>About<div>             
        </body>
        <script type="text/javascript" src="~/lib/layout.js"></script>
    </html>

if required is set to true "@RenderSection("scripts", required: true)", When page renders and user is on ABOUT page, the contacts.js STILL gets rendered.

<html>
    <body><div>About<div>             
    </body>
    <script type="text/javascript" src="~/lib/layout.js"></script>
    <script type="text/javascript" src="~/lib/contacts.js"></script>
</html>

IN SHORT, when set to true, whether you need it or not on other pages, it will get rendered anyhow. If set to false, it will render only when the child page is rendered.

How can I use NSError in my iPhone App?

Well it's a little bit out of question scope but in case you don't have an option for NSError you can always display the Low level error:

 NSLog(@"Error = %@ ",[NSString stringWithUTF8String:strerror(errno)]);

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

I got the same problem and I have read that this happened in Samsung phones only...But the reality showed that this happens in a lot of brands.

After testing I realized that this happens only when you scroll fast the RecyclerView and then you go back either with the back button or the Up button. So I put inside Up button and onBackpressed the below snippet:

someList = new ArrayList<>();
mainRecyclerViewAdapter = new MainRecyclerViewAdapter(this, someList, this);
recyclerViewMain.setAdapter(mainRecyclerViewAdapter);
finish();

With this solution you just load a new Arraylist to the adapter and new adapter to recyclerView and then you finish activity.

Hope it helps someone

Using regular expressions to do mass replace in Notepad++ and Vim

In vim

:%s/<option value='.\{1,}' >//

or

:%s/<option value='.\+' >//

In vim regular expressions you have to escape the one-or-more symbol, capturing parentheses, the bounded number curly braces and some others.

See :help /magic to see which special characters need to be escaped (and how to change that).

What is the best regular expression to check if a string is a valid URL?

 
        function validateURL(textval) {
            var urlregex = new RegExp(
            "^(http|https|ftp)\://([a-zA-Z0-9\.\-]+(\:[a-zA-Z0-9\.&amp;%\$\-]+)*@)*((25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9])\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[1-9]|0)\.(25[0-5]|2[0-4][0-9]|[0-1]{1}[0-9]{2}|[1-9]{1}[0-9]{1}|[0-9])|localhost|([a-zA-Z0-9\-]+\.)*[a-zA-Z0-9\-]+\.(com|edu|gov|int|mil|net|org|biz|arpa|info|name|pro|aero|coop|museum|[a-zA-Z]{2}))(\:[0-9]+)*(/($|[a-zA-Z0-9\.\,\?\'\\\+&amp;%\$#\=~_\-]+))*$");
            return urlregex.test(textval);
        }

Matches http://site.com/dir/file.php?var=moo | ftp://user:[email protected]:21/file/dir

Non-Matches site.com | http://site.com/dir//

Find and replace string values in list

Beside list comprehension, you can try map

>>> map(lambda x: str.replace(x, "[br]", "<br/>"), words)
['how', 'much', 'is<br/>', 'the', 'fish<br/>', 'no', 'really']

How to hash some string with sha256 in Java?

Here is a slightly more performant way to turn the digest into a hex string:

private static final char[] hexArray = "0123456789abcdef".toCharArray();

public static String getSHA256(String data) {
    StringBuilder sb = new StringBuilder();
    try {
        MessageDigest md = MessageDigest.getInstance("SHA-256");
        md.update(data.getBytes());
        byte[] byteData = md.digest();
        sb.append(bytesToHex(byteData);
    } catch(Exception e) {
        e.printStackTrace();
    }
    return sb.toString();
}

private static String bytesToHex(byte[] bytes) {
    char[] hexChars = new char[bytes.length * 2];
    for ( int j = 0; j < bytes.length; j++ ) {
        int v = bytes[j] & 0xFF;
        hexChars[j * 2] = hexArray[v >>> 4];
        hexChars[j * 2 + 1] = hexArray[v & 0x0F];
    }
    return String.valueOf(hexChars);
}

Does anyone know of a faster way in Java?

Python update a key in dict if it doesn't exist

Use dict.setdefault():

>>> d = {1: 'one'}
>>> d.setdefault(1, '1')
'one'
>>> d    # d has not changed because the key already existed
{1: 'one'}
>>> d.setdefault(2, 'two')
'two'
>>> d
{1: 'one', 2: 'two'}

How to set gradle home while importing existing project in Android studio

I had to use this

"C:\Program Files\Android\Android Studio\gradle\gradle-4.1"

Change the version if you have a different one.

Best way to get application folder path

If you know to get the root directory:

string rootPath = Path.GetPathRoot(Application.StartupPath)

How to see remote tags?

You can list the tags on remote repository with ls-remote, and then check if it's there. Supposing the remote reference name is origin in the following.

git ls-remote --tags origin

And you can list tags local with tag.

git tag

You can compare the results manually or in script.

UnicodeDecodeError: 'ascii' codec can't decode byte 0xd1 in position 2: ordinal not in range(128)

My computer had the wrong locale set.

I first did

>>> import locale
>>> locale.getpreferredencoding(False)
'ANSI_X3.4-1968'

locale.getpreferredencoding(False) is the function called by open() when you don't provide an encoding. The output should be 'UTF-8', but in this case it's some variant of ASCII.

Then I ran the bash command locale and got this output

$ locale
LANG=
LANGUAGE=
LC_CTYPE="POSIX"
LC_NUMERIC="POSIX"
LC_TIME="POSIX"
LC_COLLATE="POSIX"
LC_MONETARY="POSIX"
LC_MESSAGES="POSIX"
LC_PAPER="POSIX"
LC_NAME="POSIX"
LC_ADDRESS="POSIX"
LC_TELEPHONE="POSIX"
LC_MEASUREMENT="POSIX"
LC_IDENTIFICATION="POSIX"
LC_ALL=

So, I was using the default Ubuntu locale, which causes Python to open files as ASCII instead of UTF-8. I had to set my locale to en_US.UTF-8

sudo apt install locales 
sudo locale-gen en_US en_US.UTF-8    
sudo dpkg-reconfigure locales

If you can't change the locale system wide, you can invoke all your Python code like this:

PYTHONIOENCODING="UTF-8" python3 ./path/to/your/script.py

or do 

export PYTHONIOENCODING="UTF-8"

to set it in the shell you run that in.

How to start http-server locally

When you're running npm install in the project's root, it installs all of the npm dependencies into the project's node_modules directory.

If you take a look at the project's node_modules directory, you should see a directory called http-server, which holds the http-server package, and a .bin folder, which holds the executable binaries from the installed dependencies. The .bin directory should have the http-server binary (or a link to it).

So in your case, you should be able to start the http-server by running the following from your project's root directory (instead of npm start):

./node_modules/.bin/http-server -a localhost -p 8000 -c-1

This should have the same effect as running npm start.

If you're running a Bash shell, you can simplify this by adding the ./node_modules/.bin folder to your $PATH environment variable:

export PATH=./node_modules/.bin:$PATH

This will put this folder on your path, and you should be able to simply run

http-server -a localhost -p 8000 -c-1

How to make a JFrame Modal in Swing java

As others mentioned, you could use JDialog. If you don't have access to the parent frame or you want to freeze the hole application just pass null as a parent:

final JDialog frame = new JDialog((JFrame)null, frameTitle, true); frame.setModal(true);
frame.getContentPane().add(panel);
frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
frame.pack();
frame.setVisible(true);

How to add an ORDER BY clause using CodeIgniter's Active Record methods?

Using this code to multiple order by in single query.

$this->db->from($this->table_name);
$this->db->order_by("column1 asc,column2 desc");
$query = $this->db->get(); 
return $query->result();

Bootstrap carousel multiple frames at once

try this.....it work in mine.... code:

<div class="container">
    <br>
    <div id="myCarousel" class="carousel slide" data-ride="carousel">
        <!-- Indicators -->
        <ol class="carousel-indicators">
            <li data-target="#myCarousel" data-slide-to="0" class="active"></li>
            <li data-target="#myCarousel" data-slide-to="1"></li>
            <li data-target="#myCarousel" data-slide-to="2"></li>
            <li data-target="#myCarousel" data-slide-to="3"></li>
        </ol>

        <!-- Wrapper for slides -->
        <div class="carousel-inner" role="listbox">
            <div class="item active">
                <div class="span4" style="padding-left: 18px;">
                    <img src="http://placehold.it/290x180" class="img-thumbnail">
                    <img src="http://placehold.it/290x180" class="img-thumbnail">
                    <img src="http://placehold.it/290x180" class="img-thumbnail">
                </div>
            </div>
            <div class="item">
                 <div class="span4" style="padding-left: 18px;">
                    <img src="http://placehold.it/290x180" class="img-thumbnail">
                    <img src="http://placehold.it/290x180" class="img-thumbnail">
                    <img src="http://placehold.it/290x180" class="img-thumbnail">
                </div>
            </div>
        </div>
        <a class="right carousel-control" href="#myCarousel" role="button" data-slide="next">
            <span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
            <span class="sr-only">Next</span>
        </a>
    </div>
</div>

When to use SELECT ... FOR UPDATE?

Short answers:

Q1: Yes.

Q2: Doesn't matter which you use.

Long answer:

A select ... for update will (as it implies) select certain rows but also lock them as if they have already been updated by the current transaction (or as if the identity update had been performed). This allows you to update them again in the current transaction and then commit, without another transaction being able to modify these rows in any way.

Another way of looking at it, it is as if the following two statements are executed atomically:

select * from my_table where my_condition;

update my_table set my_column = my_column where my_condition;

Since the rows affected by my_condition are locked, no other transaction can modify them in any way, and hence, transaction isolation level makes no difference here.

Note also that transaction isolation level is independent of locking: setting a different isolation level doesn't allow you to get around locking and update rows in a different transaction that are locked by your transaction.

What transaction isolation levels do guarantee (at different levels) is the consistency of data while transactions are in progress.

How to run a program automatically as admin on Windows 7 at startup?

You should also consider the security implications of running a process as an administrator level user or as Service. If any input is not being validated properly, such as if it is listening on a network interface. If the parser for this input doesn't validate properly, it can be abused, and possibly lead to an exploit that could run code as the elevated user. in abatishchev's example it shouldn't be much of a problem, but if it were to be deployed in an enterprise environment, do a security assessment prior to wide scale deployment.

MySQL: #1075 - Incorrect table definition; autoincrement vs another key?

I think i understand what the reason of your error. First you click auto AUTO INCREMENT field then select it as a primary key.

The Right way is First You have to select it as a primary key then you have to click auto AUTO INCREMENT field.

Very easy. Thanks

How do I create 7-Zip archives with .NET?

EggCafe 7Zip cookie example This is an example (zipping cookie) with the DLL of 7Zip.

CodePlex Wrapper This is an open source project that warp zipping function of 7z.

7Zip SDK The official SDK for 7zip (C, C++, C#, Java) <---My suggestion

.Net zip library by SharpDevelop.net

CodeProject example with 7zip

SharpZipLib Many zipping

Get selected value in dropdown list using JavaScript

You can use querySelector.

E.g.

var myElement = document.getElementById('ddlViewBy');

var myValue = myElement.querySelector('[selected]').value;

How do you fadeIn and animate at the same time?

 
$('.tooltip').animate({ opacity: 1, top: "-10px" }, 'slow');

However, this doesn't appear to work on display: none elements (as fadeIn does). So, you might need to put this beforehand:

$('.tooltip').css('display', 'block');
$('.tooltip').animate({ opacity: 0 }, 0);

How to make MySQL handle UTF-8 properly

Set your database collation to UTF-8 then apply table collation to database default.

Symfony2 : How to get form validation errors after binding the request to the form

Symfony 3 and newer

I recently made a function which creates a tree of form errors. This will be helpful for returning list of errors back to front-end. This is based on form types having:

'error_bubbling' => false

Code:

public static function getFormErrorsTree(FormInterface $form): array
{
    $errors = [];

    if (count($form->getErrors()) > 0) {
        foreach ($form->getErrors() as $error) {
            $errors[] = $error->getMessage();
        }
    } else {
        foreach ($form->all() as $child) {
            $childTree = self::getFormErrorsTree($child);

            if (count($childTree) > 0) {
                $errors[$child->getName()] = $childTree;
            }
        }
    }

    return $errors;
}

Output:

Array
(
    [name] => Array
        (
            [0] => This value is not valid.
        )

    [emails] => Array
        (
            [0] => Array
                (
                    [0] => Given e-mail is not valid.
                    [1] => Given e-mail is not valid #2.
                )
            [1] => Array
                (
                    [0] => Given e-mail is not valid.
                    [1] => Given e-mail is not valid #2.
                )

        )

)

Notice: I know that errors from deeper level fields can be overwritten if higher level has errors, but this is on purpose for my usage.

Javascript replace all "%20" with a space

Check this out: How to replace all occurrences of a string in JavaScript?

Short answer:

str.replace(/%20/g, " ");

EDIT: In this case you could also do the following:

decodeURI(str)

jQuery AJAX single file upload

A. Grab file data from the file field

The first thing to do is bind a function to the change event on your file field and a function for grabbing the file data:

// Variable to store your files
var files;

// Add events
$('input[type=file]').on('change', prepareUpload);

// Grab the files and set them to our variable
function prepareUpload(event)
{
  files = event.target.files;
}

This saves the file data to a file variable for later use.

B. Handle the file upload on submit

When the form is submitted you need to handle the file upload in its own AJAX request. Add the following binding and function:

$('form').on('submit', uploadFiles);

// Catch the form submit and upload the files
function uploadFiles(event)
{
  event.stopPropagation(); // Stop stuff happening
    event.preventDefault(); // Totally stop stuff happening

// START A LOADING SPINNER HERE

// Create a formdata object and add the files
var data = new FormData();
$.each(files, function(key, value)
{
    data.append(key, value);
});

$.ajax({
    url: 'submit.php?files',
    type: 'POST',
    data: data,
    cache: false,
    dataType: 'json',
    processData: false, // Don't process the files
    contentType: false, // Set content type to false as jQuery will tell the server its a query string request
    success: function(data, textStatus, jqXHR)
    {
        if(typeof data.error === 'undefined')
        {
            // Success so call function to process the form
            submitForm(event, data);
        }
        else
        {
            // Handle errors here
            console.log('ERRORS: ' + data.error);
        }
    },
    error: function(jqXHR, textStatus, errorThrown)
    {
        // Handle errors here
        console.log('ERRORS: ' + textStatus);
        // STOP LOADING SPINNER
    }
});
}

What this function does is create a new formData object and appends each file to it. It then passes that data as a request to the server. 2 attributes need to be set to false:

  • processData - Because jQuery will convert the files arrays into strings and the server can't pick it up.
  • contentType - Set this to false because jQuery defaults to application/x-www-form-urlencoded and doesn't send the files. Also setting it to multipart/form-data doesn't seem to work either.

C. Upload the files

Quick and dirty php script to upload the files and pass back some info:

<?php // You need to add server side validation and better error handling here

$data = array();

if(isset($_GET['files']))
{  
$error = false;
$files = array();

$uploaddir = './uploads/';
foreach($_FILES as $file)
{
    if(move_uploaded_file($file['tmp_name'], $uploaddir .basename($file['name'])))
    {
        $files[] = $uploaddir .$file['name'];
    }
    else
    {
        $error = true;
    }
}
$data = ($error) ? array('error' => 'There was an error uploading your files') : array('files' => $files);
}
else
{
    $data = array('success' => 'Form was submitted', 'formData' => $_POST);
}

echo json_encode($data);

?>

IMP: Don't use this, write your own.

D. Handle the form submit

The success method of the upload function passes the data sent back from the server to the submit function. You can then pass that to the server as part of your post:

function submitForm(event, data)
{
  // Create a jQuery object from the form
$form = $(event.target);

// Serialize the form data
var formData = $form.serialize();

// You should sterilise the file names
$.each(data.files, function(key, value)
{
    formData = formData + '&filenames[]=' + value;
});

$.ajax({
    url: 'submit.php',
    type: 'POST',
    data: formData,
    cache: false,
    dataType: 'json',
    success: function(data, textStatus, jqXHR)
    {
        if(typeof data.error === 'undefined')
        {
            // Success so call function to process the form
            console.log('SUCCESS: ' + data.success);
        }
        else
        {
            // Handle errors here
            console.log('ERRORS: ' + data.error);
        }
    },
    error: function(jqXHR, textStatus, errorThrown)
    {
        // Handle errors here
        console.log('ERRORS: ' + textStatus);
    },
    complete: function()
    {
        // STOP LOADING SPINNER
    }
});
}

Final note

This script is an example only, you'll need to handle both server and client side validation and some way to notify users that the file upload is happening. I made a project for it on Github if you want to see it working.

Referenced From

How to pass values arguments to modal.show() function in Bootstrap

Here's how i am calling my modal

<a data-toggle="modal" data-id="190" data-target="#modal-popup">Open</a>

Here's how i am obtaining value in the modal

$('#modal-popup').on('show.bs.modal', function(e) {
    console.log($(e.relatedTarget).data('id')); // 190 will be printed
});

How to stretch a fixed number of horizontal navigation items evenly and fully across a specified container

This should do it for you.

<div id="nav-wrap">
    <ul id="nav">
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
        <li><a href="#">Link</a></li>
    </ul>
</div>

#nav-wrap {
    float: left;
    height: 87px;
    width: 900px;
}

#nav {
    display: inline;
    height: 87px;
    width: 100%;
}

.nav-item {
    float: left;
    height: 87px;
    line-height: 87px;
    text-align: center;
    text-decoration: none;
    width: 150px;

}

Eclipse jump to closing brace

With Ctrl + Shift + L you can open the "key assist", where you can find all the shortcuts.

Creating a UITableView Programmatically

 
- (NSInteger)tableView:(UITableView *)theTableView numberOfRowsInSection:(NSInteger)section
{
    return 1;
}

- (UITableViewCell *)tableView:(UITableView *)theTableView  cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *cellIdentifier = @"HistoryCell";

    UITableViewCell *cell = (UITableViewCell *)[theTableView dequeueReusableCellWithIdentifier:cellIdentifier];
    if (cell == nil)
    {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
    }
    cell.descriptionLabel.text = @"Testing";
    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    //Code for selection.
}

these are UITableView delegate methods.

postgresql duplicate key violates unique constraint

Referrence - https://www.calazan.com/how-to-reset-the-primary-key-sequence-in-postgresql-with-django/

I had the same problem try this: python manage.py sqlsequencereset table_name

Eg: 

python manage.py sqlsequencereset auth

you need to run this in production settings(if you have) and you need Postgres installed to run this on the server

How to draw a path on a map using kml file?

Thank Mathias Lin, tested and it works!

In addition, sample implementation of Mathias's method in activity can be as follows.

public class DirectionMapActivity extends MapActivity {

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

        MapView mapView = (MapView) findViewById(R.id.mapview);
        mapView.setBuiltInZoomControls(true);

        // Acquire a reference to the system Location Manager
        LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE);

        String locationProvider = LocationManager.NETWORK_PROVIDER;
        Location lastKnownLocation = locationManager.getLastKnownLocation(locationProvider);

        StringBuilder urlString = new StringBuilder();
        urlString.append("http://maps.google.com/maps?f=d&hl=en");
        urlString.append("&saddr=");//from
        urlString.append( Double.toString(lastKnownLocation.getLatitude() ));
        urlString.append(",");
        urlString.append( Double.toString(lastKnownLocation.getLongitude() ));
        urlString.append("&daddr=");//to
        urlString.append( Double.toString((double)dest[0]/1.0E6 ));
        urlString.append(",");
        urlString.append( Double.toString((double)dest[1]/1.0E6 ));
        urlString.append("&ie=UTF8&0&om=0&output=kml");

        try{
            // setup the url
            URL url = new URL(urlString.toString());
            // create the factory
            SAXParserFactory factory = SAXParserFactory.newInstance();
            // create a parser
            SAXParser parser = factory.newSAXParser();
            // create the reader (scanner)
            XMLReader xmlreader = parser.getXMLReader();
            // instantiate our handler
            NavigationSaxHandler navSaxHandler = new NavigationSaxHandler();
            // assign our handler
            xmlreader.setContentHandler(navSaxHandler);
            // get our data via the url class
            InputSource is = new InputSource(url.openStream());
            // perform the synchronous parse           
            xmlreader.parse(is);
            // get the results - should be a fully populated RSSFeed instance, or null on error
            NavigationDataSet ds = navSaxHandler.getParsedData();

            // draw path
            drawPath(ds, Color.parseColor("#add331"), mapView );

            // find boundary by using itemized overlay
            GeoPoint destPoint = new GeoPoint(dest[0],dest[1]);
            GeoPoint currentPoint = new GeoPoint( new Double(lastKnownLocation.getLatitude()*1E6).intValue()
                                                ,new Double(lastKnownLocation.getLongitude()*1E6).intValue() );

            Drawable dot = this.getResources().getDrawable(R.drawable.pixel);
            MapItemizedOverlay bgItemizedOverlay = new MapItemizedOverlay(dot,this);
            OverlayItem currentPixel = new OverlayItem(destPoint, null, null );
            OverlayItem destPixel = new OverlayItem(currentPoint, null, null );
            bgItemizedOverlay.addOverlay(currentPixel);
            bgItemizedOverlay.addOverlay(destPixel);

            // center and zoom in the map
            MapController mc = mapView.getController();
            mc.zoomToSpan(bgItemizedOverlay.getLatSpanE6()*2,bgItemizedOverlay.getLonSpanE6()*2);
            mc.animateTo(new GeoPoint(
                    (currentPoint.getLatitudeE6() + destPoint.getLatitudeE6()) / 2
                    , (currentPoint.getLongitudeE6() + destPoint.getLongitudeE6()) / 2));

        } catch(Exception e) {
            Log.d("DirectionMap","Exception parsing kml.");
        }

    }
    // and the rest of the methods in activity, e.g. drawPath() etc...

MapItemizedOverlay.java

public class MapItemizedOverlay extends ItemizedOverlay{
    private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
    private Context mContext;

    public MapItemizedOverlay(Drawable defaultMarker, Context context) {
          super(boundCenterBottom(defaultMarker));
          mContext = context;
    }

    public void addOverlay(OverlayItem overlay) {
        mOverlays.add(overlay);
        populate();
    }

    @Override
    protected OverlayItem createItem(int i) {
      return mOverlays.get(i);
    }

    @Override
    public int size() {
      return mOverlays.size();
    }

}

Ajax using https on an http page

Try JSONP.

most JS libraries make it just as easy as other AJAX calls, but internally use an iframe to do the query.

if you're not using JSON for your payload, then you'll have to roll your own mechanism around the iframe.

personally, i'd just redirect form the http:// page to the https:// one

Proper use cases for Android UserManager.isUserAGoat()?

In the discipline of speech recognition, users are divided into goats and sheeps.

For instance, here on page 89:

Sheeps are people for whom speech recognition works exceptionally well, and goats are people for whom it works exceptionally poorly. Only the voice recognizer knows what separates them. People can't predict whose voice will be recognized easily and whose won't. The best policy is to design the interface so it can handle all kinds of voices in all kinds of environments

Maybe, it is planned to mark Android users as goats in the future to be able to configure the speech recognition engine for goats' needs. ;-)

Can we open pdf file using UIWebView on iOS?

WKWebView: I find this question to be the best place to let people know that they should start using WKWebview as UIWebView is now deprecated.

Objective C

WKWebView *webView = [[WKWebView alloc] initWithFrame:self.view.frame];
webView.navigationDelegate = self;
NSURL *nsurl=[NSURL URLWithString:@"https://www.example.com/document.pdf"];
NSURLRequest *nsrequest=[NSURLRequest requestWithURL:nsurl];
[webView loadRequest:nsrequest];
[self.view addSubview:webView];

Swift

let myURLString = "https://www.example.com/document.pdf"
let url = NSURL(string: myURLString)
let request = NSURLRequest(URL: url!)  
let webView = WKWebView(frame: self.view.frame)
webView.navigationDelegate = self
webView.loadRequest(request)
view.addSubview(webView)

I haven't copied this code directly from Xcode, so it might, it might contain some syntax error. Please check while using it.

event.preventDefault() vs. return false

e.preventDefault();

It simply stops the default action of an element.

Instance Ex.:-

prevents the hyperlink from following the URL, prevents the submit button to submit the form. When you have many event handlers and you just want to prevent default event from occuring, & occuring from many times, for that we need to use in the top of the function().

Reason:-

The reason to use e.preventDefault(); is that in our code so something goes wrong in the code, then it will allow to execute the link or form to get submitted or allow to execute or allow whatever action you need to do. & link or submit button will get submitted & still allow further propagation of the event.

_x000D_
_x000D_ 
<!DOCTYPE html>_x000D_
<html lang="en" dir="ltr">_x000D_
   <head>_x000D_
      <meta charset="utf-8">_x000D_
      <title></title>_x000D_
   </head>_x000D_
   <body>_x000D_
      <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
      <a href="https://www.google.com" onclick="doSomethingElse()">Preventsss page from redirect</a>_x000D_
      <script type="text/javascript">_x000D_
         function doSomethingElse(){_x000D_
           console.log("This is Test...");_x000D_
         }_x000D_
         $("a").click(function(e){_x000D_
          e.preventDefault(); _x000D_
         });_x000D_
      </script>_x000D_
   </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

return False;

It simply stops the execution of the function().

"return false;" will end the whole execution of process.

Reason:-

The reason to use return false; is that you don't want to execute the function any more in strictly mode.

_x000D_
_x000D_ 
<!DOCTYPE html>_x000D_
<html lang="en" dir="ltr">_x000D_
   <head>_x000D_
      <meta charset="utf-8">_x000D_
      <title></title>_x000D_
   </head>_x000D_
   <body>_x000D_
      <a href="#" onclick="returnFalse();">Blah</a>_x000D_
      <script type="text/javascript">_x000D_
         function returnFalse(){_x000D_
         console.log("returns false without location redirection....")_x000D_
             return false;_x000D_
             location.href = "http://www.google.com/";_x000D_
         _x000D_
         }_x000D_
      </script>_x000D_
   </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

What does "connection reset by peer" mean?

This means that a TCP RST was received and the connection is now closed. This occurs when a packet is sent from your end of the connection but the other end does not recognize the connection; it will send back a packet with the RST bit set in order to forcibly close the connection.

This can happen if the other side crashes and then comes back up or if it calls close() on the socket while there is data from you in transit, and is an indication to you that some of the data that you previously sent may not have been received.

It is up to you whether that is an error; if the information you were sending was only for the benefit of the remote client then it may not matter that any final data may have been lost. However you should close the socket and free up any other resources associated with the connection.

How can I make a jQuery UI 'draggable()' div draggable for touchscreen?

After wasting many hours, I came across this!

jquery-ui-touch-punch

It translates tap events as click events. Remember to load the script after jquery.

I got this working on the iPad and iPhone

$('#movable').draggable({containment: "parent"});

How to comment out a block of Python code in Vim

NERDcommenter is an excellent plugin for commenting which automatically detects a number of filetypes and their associated comment characters. Ridiculously easy to install using Pathogen.

Comment with <leader>cc. Uncomment with <leader>cu. And toggle comments with <leader>c<space>.

(The default <leader> key in vim is \)

Monitor network activity in Android Phones

If you are doing it from the emulator you can do it like this:

Run emulator -tcpdump emulator.cap -avd my_avd to write all the emulator's traffic to a local file on your PC and then open it in wireshark

There is a similar post that might help HERE

Android: How to overlay a bitmap and draw over a bitmap?

I can't believe no one has answered this yet! A rare occurrence on SO!

1

The question doesn't quite make sense to me. But I'll give it a stab. If you're asking about direct drawing to a canvas (polygons, shading, text etc...) vs. loading a bitmap and blitting it onto the canvas that would depend on the complexity of your drawing. As the drawing gets more complex the CPU time required will increase accordingly. However, blitting a bitmap onto a canvas will always be a constant time which is proportional to the size of the bitmap.

2

Without knowing what "something" is how can I show you how to do it? You should be able to figure out #2 from the answer for #3.

3

Assumptions:

  • bmp1 is larger than bmp2.

  • You want them both overlaid from the top left corner.

        private Bitmap overlay(Bitmap bmp1, Bitmap bmp2) {
        Bitmap bmOverlay = Bitmap.createBitmap(bmp1.getWidth(), bmp1.getHeight(), bmp1.getConfig());
        Canvas canvas = new Canvas(bmOverlay);
        canvas.drawBitmap(bmp1, new Matrix(), null);
        canvas.drawBitmap(bmp2, new Matrix(), null);
        return bmOverlay;
    }

How to increase Maximum Upload size in cPanel?

New Cpanel Settings on a Godaddy
From Cpanel go to:

  • Software
  • Select PHP version
  • Click "Switch To PHP Options" located on upper right hand corner

Increase post max size and upload max file size, save and your done.

numpy get index where value is true

To get the row numbers where at least one item is larger than 15:

>>> np.where(np.any(e>15, axis=1))
(array([1, 2], dtype=int64),)

Leave out quotes when copying from cell

To keep line breaks when pasting in notepad, replace this line in the macro:

strTemp = ActiveCell.Value

by:

strTemp = Replace(ActiveCell.Value, Chr(10), vbCrLf)

ArrayList vs List<> in C#

Yes, pretty much. List<T> is a generic class. It supports storing values of a specific type without casting to or from object (which would have incurred boxing/unboxing overhead when T is a value type in the ArrayList case). ArrayList simply stores object references. As a generic collection, List<T> implements the generic IEnumerable<T> interface and can be used easily in LINQ (without requiring any Cast or OfType call).

ArrayList belongs to the days that C# didn't have generics. It's deprecated in favor of List<T>. You shouldn't use ArrayList in new code that targets .NET >= 2.0 unless you have to interface with an old API that uses it.

Force Intellij IDEA to reread all maven dependencies

For IntelliJ IDEA 14.0

Project > [your project name] > right click > Maven > Reimport

How to get index of object by its property in JavaScript?

a prototypical way

(function(){
  if (!Array.prototype.indexOfPropertyValue){
    Array.prototype.indexOfPropertyValue = function(prop,value){
      for (var index = 0; index < this.length; index++){
        if (this[index][prop]){
          if (this[index][prop] == value){
            return index;
          }
        }
      }
      return -1;
    }
  }
 })();
 // usage:
 var Data = [
 {id_list:1, name:'Nick',token:'312312'},{id_list:2,name:'John',token:'123123'}];
 Data.indexOfPropertyValue('name','John'); // returns 1 (index of array);
 Data.indexOfPropertyValue('name','Invalid name') // returns -1 (no result);
 var indexOfArray = Data.indexOfPropertyValue('name','John');
 Data[indexOfArray] // returns desired object.

Git pull after forced update

This won't fix branches that already have the code you don't want in them (see below for how to do that), but if they had pulled some-branch and now want it to be clean (and not "ahead" of origin/some-branch) then you simply:

git checkout some-branch   # where some-branch can be replaced by any other branch
git branch base-branch -D  # where base-branch is the one with the squashed commits
git checkout -b base-branch origin/base-branch  # recreating branch with correct commits

Note: You can combine these all by putting && between them

Note2: Florian mentioned this in a comment, but who reads comments when looking for answers?

Note3: If you have contaminated branches, you can create new ones based off the new "dumb branch" and just cherry-pick commits over.

Ex:

git checkout feature-old  # some branch with the extra commits
git log                   # gives commits (write down the id of the ones you want)
git checkout base-branch  # after you have already cleaned your local copy of it as above
git checkout -b feature-new # make a new branch for your feature
git cherry-pick asdfasd   # where asdfasd is one of the commit ids you want
# repeat previous step for each commit id
git branch feature-old -D # delete the old branch

Now feature-new is your branch without the extra (possibly bad) commits!

Bash syntax error: unexpected end of file

So I found this post and the answers did not help me but i was able to figure out why it gave me the error. I had a

cat > temp.txt < EOF
some content
EOF

The issue was that i copied the above code to be in a function and inadvertently tabbed the code. Need to make sure the last EOF is not tabbed.

How to use conditional breakpoint in Eclipse?

From Eclipsepedia on how to set a conditional breakpoint:

First, set a breakpoint at a given location. Then, use the context menu on the breakpoint in the left editor margin or in the Breakpoints view in the Debug perspective, and select the breakpoint’s properties. In the dialog box, check Enable Condition, and enter an arbitrary Java condition, such as list.size()==0. Now, each time the breakpoint is reached, the expression is evaluated in the context of the breakpoint execution, and the breakpoint is either ignored or honored, depending on the outcome of the expression.

Conditions can also be expressed in terms of other breakpoint attributes, such as hit count.

Calculating the SUM of (Quantity*Price) from 2 different tables

Use:

  SELECT oi.orderid,
         SUM(oi.quantity * p.price) AS grand_total,
    FROM ORDERITEM oi
    JOIN PRODUCT p ON p.id = oi.productid
   WHERE oi.orderid = @OrderId
GROUP BY oi.orderid

Mind that if either oi.quantity or p.price is null, the SUM will return NULL.

What's a good IDE for Python on Mac OS X?

I've used WingIDE and have been very happy. Intellisense is pretty good, some other things are a bit wacky but overall it's a very productive tool

Remove Blank option from Select Option with AngularJS

For me the answer to this question was using <option value="" selected hidden /> as it was proposed by @RedSparkle plus adding ng-if="false" to work in IE.

So my full option is (has differences with what I wrote before, but this does not matter because of ng-if):

<option value="" ng-if="false" disabled hidden></option>

How to access static resources when mapping a global front controller servlet on /*

I found a simpler solution with a dummy index file.

Create a Servlet (or use the one you wanted to respond to "/") which maps to "/index.html" (Solutions mentioned here use the mapping via XML, I used the 3.0 version with annotation @WebServlet) Then create a static (empty) file at the root of the static content named "index.html"

I was using Jetty, and what happened was that the server recognized the file instead of listing the directory but when asked for the resource, my Servlet took control instead. All other static content remained unaffected.

Match line break with regular expression

By default . (any character) does not match newline characters.

This means you can simply match zero or more of any character then append the end tag.

Find: <li><a href="#">.* Replace: $0</a>

Angular (4, 5, 6, 7) - Simple example of slide in out animation on ngIf

I answered a very similar question, and here is a way of doing this :

First, create a file where you would define your animations and export them. Just to make it more clear in your app.component.ts

In the following example, I used a max-height of the div that goes from 0px (when it's hidden), to 500px, but you would change that according to what you need.

This animation uses states (in and out), that will be toggle when we click on the button, which will run the animtion.

animations.ts

import { trigger, state, style, transition,
    animate, group, query, stagger, keyframes
} from '@angular/animations';

export const SlideInOutAnimation = [
    trigger('slideInOut', [
        state('in', style({
            'max-height': '500px', 'opacity': '1', 'visibility': 'visible'
        })),
        state('out', style({
            'max-height': '0px', 'opacity': '0', 'visibility': 'hidden'
        })),
        transition('in => out', [group([
            animate('400ms ease-in-out', style({
                'opacity': '0'
            })),
            animate('600ms ease-in-out', style({
                'max-height': '0px'
            })),
            animate('700ms ease-in-out', style({
                'visibility': 'hidden'
            }))
        ]
        )]),
        transition('out => in', [group([
            animate('1ms ease-in-out', style({
                'visibility': 'visible'
            })),
            animate('600ms ease-in-out', style({
                'max-height': '500px'
            })),
            animate('800ms ease-in-out', style({
                'opacity': '1'
            }))
        ]
        )])
    ]),
]

Then in your app.component, we import the animation and create the method that will toggle the animation state.

app.component.ts

import { SlideInOutAnimation } from './animations';

@Component({
  ...
  animations: [SlideInOutAnimation]
})
export class AppComponent  {
  animationState = 'in';

  ...

  toggleShowDiv(divName: string) {
    if (divName === 'divA') {
      console.log(this.animationState);
      this.animationState = this.animationState === 'out' ? 'in' : 'out';
      console.log(this.animationState);
    }
  }
}

And here is how your app.component.html would look like :

<div class="wrapper">
  <button (click)="toggleShowDiv('divA')">TOGGLE DIV</button>
  <div [@slideInOut]="animationState" style="height: 100px; background-color: red;">
  THIS DIV IS ANIMATED</div>
  <div class="content">THIS IS CONTENT DIV</div>
</div>

slideInOut refers to the animation trigger defined in animations.ts

Here is a StackBlitz example I have created : https://angular-muvaqu.stackblitz.io/

Side note : If an error ever occurs and asks you to add BrowserAnimationsModule, just import it in your app.module.ts:

import { BrowserAnimationsModule } from '@angular/platform-browser/animations';

@NgModule({
  imports: [ ..., BrowserAnimationsModule ],
  ...
})

Debugging iframes with Chrome developer tools

Currently evaluation in the console is performed in the context of the main frame in the page and it adheres to the same cross-origin policy as the main frame itself. This means that you cannot access elements in the iframe unless the main frame can. You can still set breakpoints in and debug your code using Scripts panel though.

Update: This is no longer true. See Metagrapher's answer.

Python 3: EOF when reading a line (Sublime Text 2 is angry)

I had the same problem. The problem with the Sublime Text's default console is that it does not support input.

To solve it, you have to install a package called SublimeREPL. SublimeREPL provides a Python interpreter which accepts input.

There is an article that explains the solution in detail.

GitHub page for SublimeREPL

Hamcrest compare collections

For list of objects you may need something like this:

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.contains;
import static org.hamcrest.Matchers.allOf;
import static org.hamcrest.beans.HasPropertyWithValue.hasProperty;
import static org.hamcrest.Matchers.is;

@Test
@SuppressWarnings("unchecked")
public void test_returnsList(){

    arrange();
  
    List<MyBean> myList = act();
    
    assertThat(myList , contains(allOf(hasProperty("id",          is(7L)), 
                                       hasProperty("name",        is("testName1")),
                                       hasProperty("description", is("testDesc1"))),
                                 allOf(hasProperty("id",          is(11L)), 
                                       hasProperty("name",        is("testName2")),
                                       hasProperty("description", is("testDesc2")))));
}

Use containsInAnyOrder if you do not want to check the order of the objects.

P.S. Any help to avoid the warning that is suppresed will be really appreciated.

Truncate number to two decimal places without rounding

_x000D_
_x000D_ 
function formatLimitDecimals(value, decimals) {_x000D_
  value = value.toString().split('.')_x000D_
_x000D_
  if (value.length === 2) {_x000D_
    return Number([value[0], value[1].slice(0, decimals)].join('.'))_x000D_
  } else {_x000D_
    return Number(value[0]);_x000D_
  }_x000D_
}_x000D_
_x000D_
console.log(formatLimitDecimals(4.156, 2)); // 4.15_x000D_
console.log(formatLimitDecimals(4.156, 8)); // 4.156_x000D_
console.log(formatLimitDecimals(4.156, 0)); // 4
_x000D_
_x000D_
_x000D_

What is Bit Masking?

Masking means to keep/change/remove a desired part of information. Lets see an image-masking operation; like- this masking operation is removing any thing that is not skin-

enter image description here

We are doing AND operation in this example. There are also other masking operators- OR, XOR.

Bit-Masking means imposing mask over bits. Here is a bit-masking with AND-

     1 1 1 0 1 1 0 1   [input]
(&)  0 0 1 1 1 1 0 0    [mask]
------------------------------
     0 0 1 0 1 1 0 0  [output]

So, only the middle 4 bits (as these bits are 1 in this mask) remain.

Lets see this with XOR-

     1 1 1 0 1 1 0 1   [input]
(^)  0 0 1 1 1 1 0 0    [mask]
------------------------------
     1 1 0 1 0 0 0 1  [output]

Now, the middle 4 bits are flipped (1 became 0, 0 became 1).

So, using bit-mask we can access individual bits [examples]. Sometimes, this technique may also be used for improving performance. Take this for example-

bool isOdd(int i) {
    return i%2;
}

This function tells if an integer is odd/even. We can achieve the same result with more efficiency using bit-mask-

bool isOdd(int i) {
    return i&1;
}

Short Explanation: If the least significant bit of a binary number is 1 then it is odd; for 0 it will be even. So, by doing AND with 1 we are removing all other bits except for the least significant bit i.e.:

     55  ->  0 0 1 1 0 1 1 1   [input]
(&)   1  ->  0 0 0 0 0 0 0 1    [mask]
---------------------------------------
      1  <-  0 0 0 0 0 0 0 1  [output]

jQuery AutoComplete Trigger Change Event

Well it works for me just binding a keypress event to the search input, like this:

... Instantiate your autofill here...

    $("#CompanyList").bind("keypress", function(){
    if (nowDoing==1) {
        nowDoing = 0;
        $('#form_459174').clearForm();
    }        
});

Can you do a partial checkout with Subversion?

Indeed, thanks to the comments to my post here, it looks like sparse directories are the way to go. I believe the following should do it:

svn checkout --depth empty http://svnserver/trunk/proj
svn update --set-depth infinity proj/foo
svn update --set-depth infinity proj/bar
svn update --set-depth infinity proj/baz

Alternatively, --depth immediates instead of empty checks out files and directories in trunk/proj without their contents. That way you can see which directories exist in the repository.

As mentioned in @zigdon's answer, you can also do a non-recursive checkout. This is an older and less flexible way to achieve a similar effect:

svn checkout --non-recursive http://svnserver/trunk/proj
svn update trunk/foo
svn update trunk/bar
svn update trunk/baz

Pandas: rolling mean by time interval

To keep it basic, I used a loop and something like this to get you started (my index are datetimes):

import pandas as pd
import datetime as dt

#populate your dataframe: "df"
#...

df[df.index<(df.index[0]+dt.timedelta(hours=1))] #gives you a slice. you can then take .sum() .mean(), whatever

and then you can run functions on that slice. You can see how adding an iterator to make the start of the window something other than the first value in your dataframes index would then roll the window (you could use a > rule for the start as well for example).

Note, this may be less efficient for SUPER large data or very small increments as your slicing may become more strenuous (works for me well enough for hundreds of thousands of rows of data and several columns though for hourly windows across a few weeks)

Adding 30 minutes to time formatted as H:i in PHP

In order for that to work $time has to be a timestamp. You cannot pass in "10:00" or something like $time = date('H:i', '10:00'); which is what you seem to do, because then I get 0:30 and 1:30 as results too.

Try

$time = strtotime('10:00');

As an alternative, consider using DateTime (the below requires PHP 5.3 though):

$dt = DateTime::createFromFormat('H:i', '10:00'); // create today 10 o'clock
$dt->sub(new DateInterval('PT30M'));              // substract 30 minutes
echo $dt->format('H:i');                          // echo modified time
$dt->add(new DateInterval('PT1H'));               // add 1 hour
echo $dt->format('H:i');                          // echo modified time

or procedural if you don't like OOP

$dateTime = date_create_from_format('H:i', '10:00');
date_sub($dateTime, date_interval_create_from_date_string('30 minutes'));
echo date_format($dateTime, 'H:i');
date_add($dateTime, date_interval_create_from_date_string('1 hour'));
echo date_format($dateTime, 'H:i');

read input separated by whitespace(s) or newline...?

the user pressing enter or spaces is the same.

int count = 5;
int list[count]; // array of known length
cout << "enter the sequence of " << count << " numbers space separated: ";
// user inputs values space separated in one line.  Inputs more than the count are discarded.
for (int i=0; i<count; i++) {
    cin >> list[i];
}

MySQL Cannot Add Foreign Key Constraint

I had a similar error in creating foreign key in a Many to Many table where the primary key consisted of 2 foreign keys and another normal column. I fixed the issue by correcting the referenced table name i.e. company, as shown in the corrected code below:

create table company_life_cycle__history -- (M-M)
(
company_life_cycle_id tinyint unsigned not null,
Foreign Key (company_life_cycle_id) references company_life_cycle(id) ON DELETE    CASCADE ON UPDATE CASCADE,
company_id MEDIUMINT unsigned not null,
Foreign Key (company_id) references company(id) ON DELETE CASCADE ON UPDATE CASCADE,
activity_on date NOT NULL,
PRIMARY KEY pk_company_life_cycle_history (company_life_cycle_id, company_id,activity_on),
created_on datetime DEFAULT NULL,
updated_on datetime DEFAULT NULL,
created_by varchar(50) DEFAULT NULL,
updated_by varchar(50) DEFAULT NULL
);

How to overlay images

I just got done doing this exact thing in a project. The HTML side looked a bit like this:

<a href="[fullsize]" class="gallerypic" title="">
  <img src="[thumbnail pic]" height="90" width="140" alt="[Gallery Photo]" class="pic" />
  <span class="zoom-icon">
      <img src="/images/misc/zoom.gif" width="32" height="32" alt="Zoom">
  </span>
</a>

Then using CSS:

a.gallerypic{
  width:140px;
  text-decoration:none;
  position:relative;
  display:block;
  border:1px solid #666;
  padding:3px;
  margin-right:5px;
  float:left;
}

a.gallerypic span.zoom-icon{
  visibility:hidden;
  position:absolute;
  left:40%;
  top:35%;
  filter:alpha(opacity=50);
  -moz-opacity:0.5;
  -khtml-opacity: 0.5;
  opacity: 0.5;
}

a.gallerypic:hover span.zoom-icon{
  visibility:visible;
}

I left a lot of the sample in there on the CSS so you can see how I decided to do the style. Note I lowered the opacity so you could see through the magnifying glass.

Hope this helps.

EDIT: To clarify for your example - you could ignore the visibility:hidden; and kill the :hover execution if you wanted, this was just the way I did it.

do { ... } while (0) — what is it good for?

It is a way to simplify error checking and avoid deep nested if's. For example:

do {
  // do something
  if (error) {
    break;
  }
  // do something else
  if (error) {
    break;
  }
  // etc..
} while (0);

Good Hash Function for Strings

If you are doing this in Java then why are you doing it? Just call .hashCode() on the string

SQL: Select columns with NULL values only

Or did you want to just see if a column only has NULL values (and, thus, is probably unused)?

Further clarification of the question might help.

EDIT: Ok.. here's some really rough code to get you going...

SET NOCOUNT ON
DECLARE @TableName Varchar(100)
SET @TableName='YourTableName'
CREATE TABLE #NullColumns (ColumnName Varchar(100), OnlyNulls BIT)
INSERT INTO #NullColumns (ColumnName, OnlyNulls) SELECT c.name, 0 FROM syscolumns c INNER JOIN sysobjects o ON c.id = o.id AND o.name = @TableName AND o.xtype = 'U'
DECLARE @DynamicSQL AS Nvarchar(2000)
DECLARE @ColumnName Varchar(100)
DECLARE @RC INT
    SELECT TOP 1 @ColumnName = ColumnName FROM #NullColumns WHERE OnlyNulls=0
    WHILE @@ROWCOUNT > 0
    BEGIN
        SET @RC=0
        SET @DynamicSQL = 'SELECT TOP 1 1 As HasNonNulls FROM ' + @TableName + ' (nolock) WHERE ''' + @ColumnName + ''' IS NOT NULL'
        EXEC sp_executesql @DynamicSQL
        set @RC=@@rowcount
        IF @RC=1
        BEGIN
            SET @DynamicSQL = 'UPDATE #NullColumns SET OnlyNulls=1 WHERE ColumnName=''' + @ColumnName + ''''
            EXEC sp_executesql @DynamicSQL
        END
        ELSE
        BEGIN
            SET @DynamicSQL = 'DELETE FROM #NullColumns WHERE ColumnName=''' + @ColumnName+ ''''
            EXEC sp_executesql @DynamicSQL
        END
    SELECT TOP 1 @ColumnName = ColumnName FROM #NullColumns WHERE OnlyNulls=0
    END

SELECT * FROM #NullColumns

DROP TABLE #NullColumns
SET NOCOUNT OFF

Yes, there are easier ways, but I have a meeting to go to right now. Good luck!

MySQL DISTINCT on a GROUP_CONCAT()

Using DISTINCT will work 

SELECT GROUP_CONCAT(DISTINCT(categories) SEPARATOR ' ') FROM table

REf:- this

Adding an image to a PDF using iTextSharp and scale it properly

Personally, I use something close from fubo's solution and it works well:

image.ScaleToFit(document.PageSize);
image.SetAbsolutePosition(0,0);

Run a Docker image as a container

Since you have created an image from the Dockerfile, the image currently is not in active state. In order to work you need to run this image inside a container.

The $ docker images command describes how many images are currently available in the local repository. and

docker ps -a

shows how many containers are currently available, i.e. the list of active and exited containers.

There are two ways to run the image in the container:

$ docker run [OPTIONS] IMAGE[:TAG|@DIGEST] [COMMAND] [ARG...]

In detached mode:

-d=false: Detached mode: Run container in the background, print new container id

In interactive mode:

-i :Keep STDIN open even if not attached

Here is the Docker run command

$ docker run image_name:tag_name

For more clarification on Docker run, you can visit Docker run reference.

It's the best material to understand Docker.

Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sierra/Mojave?

What did work for me (inspired from aax' thanks) :

Paste this into /Library/LaunchDaemons/com.apple.launchd.limit.plist then reboot :

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
  <plist version="1.0">
  <dict>
  <key>Label</key>
  <string>eicar</string>
  <key>ProgramArguments</key>
  <array>
    <string>/bin/launchctl</string>
    <string>limit</string>
    <string>maxfiles</string>
    <string>16384</string>
    <string>16384</string>
  </array>
  <key>RunAtLoad</key>
  <true/>
  <key>ServiceIPC</key>
  <false/>
</dict>
</plist>

If you need it step by step :

  • Launch terminal
  • Type sudo su then enter your password to log in as root
  • Type vi /Library/LaunchDaemons/com.apple.launchd.limit.plist
  • When into the vi editor, press the key i to enter insert mode then paste the exact code content above (?+v). This will force the limit to 16384 files per process and 16384 files total
  • Save your file and quit using esc then :wq
  • Reboot your system, and check that it is working using the command launchctl limit

I hope this helped you.

is there a 'block until condition becomes true' function in java?

Lock-free solution(?)

I had the same issue, but I wanted a solution that didn't use locks.

Problem: I have at most one thread consuming from a queue. Multiple producer threads are constantly inserting into the queue and need to notify the consumer if it's waiting. The queue is lock-free so using locks for notification causes unnecessary blocking in producer threads. Each producer thread needs to acquire the lock before it can notify the waiting consumer. I believe I came up with a lock-free solution using LockSupport and AtomicReferenceFieldUpdater. If a lock-free barrier exists within the JDK, I couldn't find it. Both CyclicBarrier and CoundDownLatch use locks internally from what I could find.

This is my slightly abbreviated code. Just to be clear, this code will only allow one thread to wait at a time. It could be modified to allow for multiple awaiters/consumers by using some type of atomic collection to store multiple owner (a ConcurrentMap may work).

I have used this code and it seems to work. I have not tested it extensively. I suggest you read the documentation for LockSupport before use.

/* I release this code into the public domain.
 * http://unlicense.org/UNLICENSE
 */

import java.util.concurrent.atomic.AtomicReferenceFieldUpdater;
import java.util.concurrent.locks.LockSupport;

/**
 * A simple barrier for awaiting a signal.
 * Only one thread at a time may await the signal.
 */
public class SignalBarrier {
    /**
     * The Thread that is currently awaiting the signal.
     * !!! Don't call this directly !!!
     */
    @SuppressWarnings("unused")
    private volatile Thread _owner;

    /** Used to update the owner atomically */
    private static final AtomicReferenceFieldUpdater<SignalBarrier, Thread> ownerAccess =
        AtomicReferenceFieldUpdater.newUpdater(SignalBarrier.class, Thread.class, "_owner");

    /** Create a new SignalBarrier without an owner. */
    public SignalBarrier() {
        _owner = null;
    }

    /**
     * Signal the owner that the barrier is ready.
     * This has no effect if the SignalBarrer is unowned.
     */
    public void signal() {
        // Remove the current owner of this barrier.
        Thread t = ownerAccess.getAndSet(this, null);

        // If the owner wasn't null, unpark it.
        if (t != null) {
            LockSupport.unpark(t);
        }
    }

    /**
     * Claim the SignalBarrier and block until signaled.
     *
     * @throws IllegalStateException If the SignalBarrier already has an owner.
     * @throws InterruptedException If the thread is interrupted while waiting.
     */
    public void await() throws InterruptedException {
        // Get the thread that would like to await the signal.
        Thread t = Thread.currentThread();

        // If a thread is attempting to await, the current owner should be null.
        if (!ownerAccess.compareAndSet(this, null, t)) {
            throw new IllegalStateException("A second thread tried to acquire a signal barrier that is already owned.");
        }

        // The current thread has taken ownership of this barrier.
        // Park the current thread until the signal. Record this
        // signal barrier as the 'blocker'.
        LockSupport.park(this);
        // If a thread has called #signal() the owner should already be null.
        // However the documentation for LockSupport.unpark makes it clear that
        // threads can wake up for absolutely no reason. Do a compare and set
        // to make sure we don't wipe out a new owner, keeping in mind that only
        // thread should be awaiting at any given moment!
        ownerAccess.compareAndSet(this, t, null);

        // Check to see if we've been unparked because of a thread interrupt.
        if (t.isInterrupted())
            throw new InterruptedException();
    }

    /**
     * Claim the SignalBarrier and block until signaled or the timeout expires.
     *
     * @throws IllegalStateException If the SignalBarrier already has an owner.
     * @throws InterruptedException If the thread is interrupted while waiting.
     *
     * @param timeout The timeout duration in nanoseconds.
     * @return The timeout minus the number of nanoseconds that passed while waiting.
     */
    public long awaitNanos(long timeout) throws InterruptedException {
        if (timeout <= 0)
            return 0;
        // Get the thread that would like to await the signal.
        Thread t = Thread.currentThread();

        // If a thread is attempting to await, the current owner should be null.
        if (!ownerAccess.compareAndSet(this, null, t)) {
            throw new IllegalStateException("A second thread tried to acquire a signal barrier is already owned.");
        }

        // The current thread owns this barrier.
        // Park the current thread until the signal. Record this
        // signal barrier as the 'blocker'.
        // Time the park.
        long start = System.nanoTime();
        LockSupport.parkNanos(this, timeout);
        ownerAccess.compareAndSet(this, t, null);
        long stop = System.nanoTime();

        // Check to see if we've been unparked because of a thread interrupt.
        if (t.isInterrupted())
            throw new InterruptedException();

        // Return the number of nanoseconds left in the timeout after what we
        // just waited.
        return Math.max(timeout - stop + start, 0L);
    }
}

To give a vague example of usage, I'll adopt james large's example:

SignalBarrier barrier = new SignalBarrier();

Consumer thread (singular, not plural!):

try {
    while(!conditionIsTrue()) {
        barrier.await();
    }
    doSomethingThatRequiresConditionToBeTrue();
} catch (InterruptedException e) {
    handleInterruption();
}

Producer thread(s):

doSomethingThatMakesConditionTrue();
barrier.signal();

How do I get rid of the b-prefix in a string in python?

****How to remove b' ' chars which is decoded string in python ****

import base64
a='cm9vdA=='
b=base64.b64decode(a).decode('utf-8')
print(b)

Underscore prefix for property and method names in JavaScript

That's only a convention. The Javascript language does not give any special meaning to identifiers starting with underscore characters.

That said, it's quite a useful convention for a language that doesn't support encapsulation out of the box. Although there is no way to prevent someone from abusing your classes' implementations, at least it does clarify your intent, and documents such behavior as being wrong in the first place.

Search for exact match of string in excel row using VBA Macro

Try this:

Sub GetColumns()

Dim lnRow As Long, lnCol As Long

lnRow = 3 'For testing

lnCol = Sheet1.Cells(lnRow, 1).EntireRow.Find(What:="sds", LookIn:=xlValues, LookAt:=xlPart, SearchOrder:=xlByColumns, SearchDirection:=xlNext, MatchCase:=False).Column

End Sub

Probably best not to use colIndex and rowIndex as variable names as they are already mentioned in the Excel Object Library.

No Spring WebApplicationInitializer types detected on classpath

tomcat-maven-plugin in test

Tomcat usually does not add classes in src/test/java to the classpath. They are missing if you run tomcat in scope test. To order tomcat to respect classes in test, use -Dmaven.tomcat.useTestClasspath=true or add 

<properties>
   <maven.tomcat.useTestClasspath>true</maven.tomcat.useTestClasspath>
</properties>

To your pom.xml.

How to replace deprecated android.support.v4.app.ActionBarDrawerToggle

There's no need for you to use super-call of the ActionBarDrawerToggle which requires the Toolbar. This means instead of using the following constructor:

ActionBarDrawerToggle(Activity activity, DrawerLayout drawerLayout, Toolbar toolbar, int openDrawerContentDescRes, int closeDrawerContentDescRes)

You should use this one:

ActionBarDrawerToggle(Activity activity, DrawerLayout drawerLayout, int openDrawerContentDescRes, int closeDrawerContentDescRes)

So basically the only thing you have to do is to remove your custom drawable:

super(mActivity, mDrawerLayout, R.string.ns_menu_open, R.string.ns_menu_close);

More about the "new" ActionBarDrawerToggle in the Docs (click).