Programs & Examples On #Out of band

out of band is used in communcations for data out of the expected communcation range

Find UNC path of a network drive?

This question has been answered already, but since there is a more convenient way to get the UNC path and some more I recommend using Path Copy, which is free and you can practically get any path you want with one click:

https://pathcopycopy.github.io/

Here is a screenshot demonstrating how it works. The latest version has more options and definitely UNC Path too:

enter image description here

Angular @ViewChild() error: Expected 2 arguments, but got 1

it is because view child require two argument try like this

@ViewChild('nameInput', { static: false, }) nameInputRef: ElementRef;

@ViewChild('amountInput', { static: false, }) amountInputRef: ElementRef;

How to move table from one tablespace to another in oracle 11g

Moving tables:

First run:

SELECT 'ALTER TABLE <schema_name>.' || OBJECT_NAME ||' MOVE TABLESPACE '||' <tablespace_name>; '
FROM ALL_OBJECTS
WHERE OWNER = '<schema_name>'
AND OBJECT_TYPE = 'TABLE' <> '<TABLESPACE_NAME>';

-- Or suggested in the comments (did not test it myself)

SELECT 'ALTER TABLE <SCHEMA>.' || TABLE_NAME ||' MOVE TABLESPACE '||' TABLESPACE_NAME>; ' 
FROM dba_tables 
WHERE OWNER = '<SCHEMA>' 
AND TABLESPACE_NAME <> '<TABLESPACE_NAME>

Where <schema_name> is the name of the user. And <tablespace_name> is the destination tablespace.

As a result you get lines like:

ALTER TABLE SCOT.PARTS MOVE TABLESPACE USERS;

Paste the results in a script or in a oracle sql developer like application and run it.

Moving indexes:

First run:

SELECT 'ALTER INDEX <schema_name>.'||INDEX_NAME||' REBUILD TABLESPACE <tablespace_name>;' 
FROM ALL_INDEXES
WHERE OWNER = '<schema_name>'
AND TABLESPACE_NAME NOT LIKE '<tablespace_name>';

The last line in this code could save you a lot of time because it filters out the indexes which are already in the correct tablespace.

As a result you should get something like:

ALTER INDEX SCOT.PARTS_NO_PK REBUILD TABLESPACE USERS;

Paste the results in a script or in a oracle sql developer like application and run it.

Last but not least, moving LOBs:

First run:

SELECT 'ALTER TABLE <schema_name>.'||LOWER(TABLE_NAME)||' MOVE LOB('||LOWER(COLUMN_NAME)||') STORE AS (TABLESPACE <table_space>);'
FROM DBA_TAB_COLS
WHERE OWNER = '<schema_name>' AND DATA_TYPE like '%LOB%';

This moves the LOB objects to the other tablespace.

As a result you should get something like:

ALTER TABLE SCOT.bin$6t926o3phqjgqkjabaetqg==$0 MOVE LOB(calendar) STORE AS (TABLESPACE USERS);

Paste the results in a script or in a oracle sql developer like application and run it.

O and there is one more thing:

For some reason I wasn't able to move 'DOMAIN' type indexes. As a work around I dropped the index. changed the default tablespace of the user into de desired tablespace. and then recreate the index again. There is propably a better way but it worked for me.

iOS start Background Thread

Enable NSZombieEnabled to know which object is being released and then accessed. Then check if the getResultSetFromDB: has anything to do with that. Also check if docids has anything inside and if it is being retained.

This way you can be sure there is nothing wrong.

Launching a website via windows commandline

You can start web pages using command line in any browser typing this command

cd %your chrome directory%
start /max http://google.com

save it as bat and run it :)

What is the difference between a candidate key and a primary key?

Think of a table of vehicles with an integer Primary Key.

The registration number would be a candidate key.

In the real world registration numbers are subject change so it depends somewhat on the circumstances what might qualify as a candidate key.

Oracle timestamp data type

The number in parentheses specifies the precision of fractional seconds to be stored. So, (0) would mean don't store any fraction of a second, and use only whole seconds. The default value if unspecified is 6 digits after the decimal separator.

So an unspecified value would store a date like:

TIMESTAMP 24-JAN-2012 08.00.05.993847 AM

And specifying (0) stores only:

TIMESTAMP(0) 24-JAN-2012 08.00.05 AM

See Oracle documentation on data types.

How to pass a JSON array as a parameter in URL

Send Json data string to a web address and get a result with method post

in C#

public string SendJsonToUrl(string Url, string StrJsonData)
{
    if (Url == "" || StrJsonData == "") return "";
    try
    {
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
        request.Method = "POST";
        request.ContentType = "application/json";
        request.ContentLength = StrJsonData.Length;
        using (var streamWriter = new StreamWriter(request.GetRequestStream()))
        {
            streamWriter.Write(StrJsonData);
            streamWriter.Close();
            var httpResponse = (HttpWebResponse)request.GetResponse();
            using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))
            {
                var result = streamReader.ReadToEnd();
                return result;
            }
        }
    }
    catch (Exception exp)
    {
        throw new Exception("SendJsonToUrl", exp);
    }
}

in PHP

<?php

$input = file_get_contents('php://input');
$json = json_decode($input ,true);

?>

Declare a dictionary inside a static class

The correct syntax ( as tested in VS 2008 SP1), is this:

public static class ErrorCode
{
    public static IDictionary<string, string> ErrorCodeDic;
     static ErrorCode()
    {
        ErrorCodeDic = new Dictionary<string, string>()
            { {"1", "User name or password problem"} };
    }
}

Why is char[] preferred over String for passwords?

The short and straightforward answer would be because char[] is mutable while String objects are not.

Strings in Java are immutable objects. That is why they can't be modified once created, and therefore the only way for their contents to be removed from memory is to have them garbage collected. It will be only then when the memory freed by the object can be overwritten, and the data will be gone.

Now garbage collection in Java doesn't happen at any guaranteed interval. The String can thus persist in memory for a long time, and if a process crashes during this time, the contents of the string may end up in a memory dump or some log.

With a character array, you can read the password, finish working with it as soon as you can, and then immediately change the contents.

Padding between ActionBar's home icon and title

Im using a custom image instead of the default title text to the right of my apps logo. This is set up programatically like

    actionBar.setDisplayHomeAsUpEnabled(true);
    actionBar.setDisplayUseLogoEnabled(true);
    actionBar.setCustomView(R.layout.include_ab_txt_logo);
    actionBar.setDisplayShowCustomEnabled(true);

The issues with the above answers for me are @Cliffus's suggestion does not work for me due to the issues others have outlined in the comments and while @dushyanth programatic padding setting may have worked in the past I would think that the fact that the spacing is now set using android:layout_marginEnd="8dip" since API 17 manually setting the padding should have no effect. See the link he posted to git to verify its current state.

A simple solution for me is to set a negative margin on my custom view in the actionBar, like so android:layout_marginLeft="-14dp". A quick test shows it works for me on 2.3.3 and 4.3 using ActionBarCompat

Hope this helps someone!

com.jcraft.jsch.JSchException: UnknownHostKey

Just substitute "user", "pass", "SSHD_IP". And create a file called known_hosts.txt with the content of the server's ~/.ssh/known_hosts. You will get a shell.

public class Known_Hosts {
public static void main(String[] arg) {
    try {
        JSch jsch = new JSch();
        jsch.setKnownHosts("known_hosts.txt");
        Session session = jsch.getSession("user", "SSHD_IP", 22);
        session.setPassword("pass");
        session.connect();
        Channel channel = session.openChannel("shell");
        channel.setInputStream(System.in);
        channel.setOutputStream(System.out);
        channel.connect();
    } catch (Exception e) {
        System.out.println(e);
    }
  }
}

HTML+CSS: How to force div contents to stay in one line?

div {
    display: flex;
    flex-direction: row; 
}

was the solution that worked for me. In some cases with div-lists this is needed.

some alternative direction values are row-reverse, column, column-reverse, unset, initial, inherit which do the things you expect them to do

Angular 2: Passing Data to Routes?

You can't pass objects using router params, only strings because it needs to be reflected in the URL. It would be probably a better approach to use a shared service to pass data around between routed components anyway.

The old router allows to pass data but the new (RC.1) router doesn't yet.

Update

data was re-introduced in RC.4 How do I pass data in Angular 2 components while using Routing?

Cocoa Touch: How To Change UIView's Border Color And Thickness?

I wanted to add this to @marczking's answer (Option 1) as a comment, but my lowly status on StackOverflow is preventing that.

I did a port of @marczking's answer to Objective C. Works like charm, thanks @marczking!

UIView+Border.h:

#import <UIKit/UIKit.h>

IB_DESIGNABLE
@interface UIView (Border)

-(void)setBorderColor:(UIColor *)color;
-(void)setBorderWidth:(CGFloat)width;
-(void)setCornerRadius:(CGFloat)radius;

@end

UIView+Border.m:

#import "UIView+Border.h"

@implementation UIView (Border)
// Note: cannot use synthesize in a Category

-(void)setBorderColor:(UIColor *)color
{
    self.layer.borderColor = color.CGColor;
}

-(void)setBorderWidth:(CGFloat)width
{
    self.layer.borderWidth = width;
}

-(void)setCornerRadius:(CGFloat)radius
{
    self.layer.cornerRadius = radius;
    self.layer.masksToBounds = radius > 0;
}

@end

Plotting using a CSV file

You can also plot to a png file using gnuplot (which is free):

terminal commands

gnuplot> set title '<title>'
gnuplot> set ylabel '<yLabel>'
gnuplot> set xlabel '<xLabel>'
gnuplot> set grid
gnuplot> set term png
gnuplot> set output '<Output file name>.png'
gnuplot> plot '<fromfile.csv>'

note: you always need to give the right extension (.png here) at set output

Then it is also possible that the ouput is not lines, because your data is not continues. To fix this simply change the 'plot' line to:

plot '<Fromfile.csv>' with line lt -1 lw 2

More line editing options (dashes and line color ect.) at: http://gnuplot.sourceforge.net/demo_canvas/dashcolor.html

  • gnuplot is available in most linux distros via the package manager (e.g. on an apt based distro, run apt-get install gnuplot)
  • gnuplot is available in windows via Cygwin
  • gnuplot is available on macOS via homebrew (run brew install gnuplot)

How to test web service using command line curl

From the documentation on http://curl.haxx.se/docs/httpscripting.html :

HTTP Authentication

curl --user name:password http://www.example.com 

Put a file to a HTTP server with curl:

curl --upload-file uploadfile http://www.example.com/receive.cgi

Send post data with curl:

curl --data "birthyear=1905&press=%20OK%20" http://www.example.com/when.cgi

AngularJS. How to call controller function from outside of controller component

I've found an example on the internet.

Some guy wrote this code and worked perfectly

HTML

<div ng-cloak ng-app="ManagerApp">
    <div id="MainWrap" class="container" ng-controller="ManagerCtrl">
       <span class="label label-info label-ext">Exposing Controller Function outside the module via onClick function call</span>
       <button onClick='ajaxResultPost("Update:Name:With:JOHN","accept",true);'>click me</button>
       <br/> <span class="label label-warning label-ext" ng-bind="customParams.data"></span>
       <br/> <span class="label label-warning label-ext" ng-bind="customParams.type"></span>
       <br/> <span class="label label-warning label-ext" ng-bind="customParams.res"></span>
       <br/>
       <input type="text" ng-model="sampletext" size="60">
       <br/>
    </div>
</div>

JAVASCRIPT

var angularApp = angular.module('ManagerApp', []);
angularApp.controller('ManagerCtrl', ['$scope', function ($scope) {

$scope.customParams = {};

$scope.updateCustomRequest = function (data, type, res) {
    $scope.customParams.data = data;
    $scope.customParams.type = type;
    $scope.customParams.res = res;
    $scope.sampletext = "input text: " + data;
};



}]);

function ajaxResultPost(data, type, res) {
    var scope = angular.element(document.getElementById("MainWrap")).scope();
    scope.$apply(function () {
    scope.updateCustomRequest(data, type, res);
    });
}

Demo

*I did some modifications, see original: font JSfiddle

How can I create a simple index.html file which lists all files/directories?

Did you try to allow it for this directory via .htaccess?

Options +Indexes

I use this for some of my directories where directory listing is disabled by my provider

React onClick function fires on render

JSX is used with ReactJS as it is very similar to HTML and it gives programmers feel of using HTML whereas it ultimately transpiles to a javascript file.

Writing a for-loop and specifying function as {this.props.removeTaskFunction(todo)} will execute the functions whenever the loop is triggered .

To stop this behaviour we need to return the function to onClick.

The fat arrow function has a hidden return statement along with the bind property. Thus it returns the function to OnClick as Javascript can return functions too !!!!!

Use -

onClick={() => { this.props.removeTaskFunction(todo) }}

which means-

var onClick = function() {
  return this.props.removeTaskFunction(todo);
}.bind(this);

If else on WHERE clause

You want to use coalesce():

where coalesce(email, email2) like '%[email protected]%'

If you want to handle empty strings ('') versus NULL, a case works:

where (case when email is NULL or email = '' then email2 else email end) like '%[email protected]%'

And, if you are worried about the string really being just spaces:

where (case when email is NULL or ltrim(email) = '' then email2 else email end) like '%[email protected]%'

As an aside, the sample if statement is really saying "If email starts with a number larger than 0". This is because the comparison is to 0, a number. MySQL implicitly tries to convert the string to a number. So, '[email protected]' would fail, because the string would convert as 0. As would '[email protected]'. But, '[email protected]' and '[email protected]' would succeed.

Insert data into table with result from another select query

Below is an example of such a query:

INSERT INTO [93275].[93276].[93277].[93278] ( [Mobile Number], [Mobile Series], [Full Name], [Full Address], [Active Date], company ) IN 'I:\For Test\90-Mobile Series.accdb
SELECT [1].[Mobile Number], [1].[Mobile Series], [1].[Full Name], [1].[Full Address], [1].[Active Date], [1].[Company Name]
FROM 1
WHERE ((([1].[Mobile Series])="93275" Or ([1].[Mobile Series])="93276")) OR ((([1].[Mobile Series])="93277"));OR ((([1].[Mobile Series])="93278"));

How could I convert data from string to long in c#

You can create your own conversion function:

    static long ToLong(string lNumber)
    {
        if (string.IsNullOrEmpty(lNumber))
            throw new Exception("Not a number!");
        char[] chars = lNumber.ToCharArray();
        long result = 0;
        bool isNegative = lNumber[0] == '-';
        if (isNegative && lNumber.Length == 1)
            throw new Exception("- Is not a number!");

        for (int i = (isNegative ? 1:0); i < lNumber.Length; i++)
        {
            if (!Char.IsDigit(chars[i]))
            {
                if (chars[i] == '.' && i < lNumber.Length - 1 && Char.IsDigit(chars[i+1]))
                {
                    var firstDigit = chars[i + 1] - 48;
                    return (isNegative ? -1L:1L) * (result + ((firstDigit < 5) ? 0L : 1L));    
                }
                throw new InvalidCastException($" {lNumber} is not a valid number!");
            }
            result = result * 10 + ((long)chars[i] - 48L);
        }
        return (isNegative ? -1L:1L) * result;
    }

It can be improved further:

  • performance wise
  • make the validation stricter in the sense that it currently doesn't care if characters after first decimal aren't digits
  • specify rounding behavior as parameter for conversion function. it currently does rounding

Best lightweight web server (only static content) for Windows

The smallest one I know is lighttpd.

Security, speed, compliance, and flexibility -- all of these describe lighttpd (pron. lighty) which is rapidly redefining efficiency of a webserver; as it is designed and optimized for high performance environments. With a small memory footprint compared to other web-servers, effective management of the cpu-load, and advanced feature set (FastCGI, SCGI, Auth, Output-Compression, URL-Rewriting and many more) lighttpd is the perfect solution for every server that is suffering load problems. And best of all it's Open Source licensed under the revised BSD license.

Edit: removed Windows version link, now a spam/malware plugin site.

How to delete rows from a pandas DataFrame based on a conditional expression

In pandas you can do str.len with your boundary and using the Boolean result to filter it .

df[df['column name'].str.len().lt(2)]

HTML5 Video autoplay on iPhone

I had a similar problem and I tried multiple solution. I solved it implementing 2 considerations.

  1. Using dangerouslySetInnerHtml to embed the <video> code. For example:
<div dangerouslySetInnerHTML={{ __html: `
    <video class="video-js" playsinline autoplay loop muted>
        <source src="../video_path.mp4" type="video/mp4"/>
    </video>`}}
/>
  1. Resizing the video weight. I noticed my iPhone does not autoplay videos over 3 megabytes. So I used an online compressor tool (https://www.mp4compress.com/) to go from 4mb to less than 500kb

Also, thanks to @boltcoder for his guide: Autoplay muted HTML5 video using React on mobile (Safari / iOS 10+)

cursor.fetchall() vs list(cursor) in Python

list(cursor) works because a cursor is an iterable; you can also use cursor in a loop:

for row in cursor:
    # ...

A good database adapter implementation will fetch rows in batches from the server, saving on the memory footprint required as it will not need to hold the full result set in memory. cursor.fetchall() has to return the full list instead.

There is little point in using list(cursor) over cursor.fetchall(); the end effect is then indeed the same, but you wasted an opportunity to stream results instead.

ERROR 1064 (42000): You have an error in your SQL syntax; Want to configure a password as root being the user

This is the only command that worked for me. (I got it from M 8.0 documentation)

ALTER USER 'root'@'*' IDENTIFIED WITH mysql_native_password BY 'YOURPASSWORD';
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'YOURPASSWORD';

In React Native, how do I put a view on top of another view, with part of it lying outside the bounds of the view behind?

import React, {Component} from 'react';
import {StyleSheet, View} from 'react-native';


export default class App extends Component {
  render() {
    return (
       <View>// you need to wrap the two Views an another View
          <View style={styles.box1}></View>
          <View style={styles.box2}></View>
       </View> 
    );
  }
}

const styles = StyleSheet.create({
  box1:{
    height:100,
    width:100,
    backgroundColor:'red'
  },
  box2:{
    height:100,
    width:100,
    backgroundColor:'green',
    position: 'absolute',
    top:10,
    left:30

  },
});

How to convert integer to string in C?

That's because itoa isn't a standard function. Try snprintf instead.

char str[LEN];
snprintf(str, LEN, "%d", 42);

Postgres and Indexes on Foreign Keys and Primary Keys

PostgreSQL automatically creates indexes on primary keys and unique constraints, but not on the referencing side of foreign key relationships.

When Pg creates an implicit index it will emit a NOTICE-level message that you can see in psql and/or the system logs, so you can see when it happens. Automatically created indexes are visible in \d output for a table, too.

The documentation on unique indexes says:

PostgreSQL automatically creates an index for each unique constraint and primary key constraint to enforce uniqueness. Thus, it is not necessary to create an index explicitly for primary key columns.

and the documentation on constraints says:

Since a DELETE of a row from the referenced table or an UPDATE of a referenced column will require a scan of the referencing table for rows matching the old value, it is often a good idea to index the referencing columns. Because this is not always needed, and there are many choices available on how to index, declaration of a foreign key constraint does not automatically create an index on the referencing columns.

Therefore you have to create indexes on foreign-keys yourself if you want them.

Note that if you use primary-foreign-keys, like 2 FK's as a PK in a M-to-N table, you will have an index on the PK and probably don't need to create any extra indexes.

While it's usually a good idea to create an index on (or including) your referencing-side foreign key columns, it isn't required. Each index you add slows DML operations down slightly, so you pay a performance cost on every INSERT, UPDATE or DELETE. If the index is rarely used it may not be worth having.

How to turn off page breaks in Google Docs?

This answer is a summary of comments; but it really deserves its own answer.

The accepted answer (by @BjarkeCK) works, but as written, there is a maximum allowable page height of about 120 inches — roughly the height of 11 normal sized pages. So this is not a perfect solution.

However, there is a hack. You have to edit the source code of your local browser which renders the Page-Sizer settings window and either increase or delete the max attribute for the page height input. As shown in the following screen shot.

Page-Sizer Add-on

enter image description here

To access the source code you need to edit, position your cursor inside the custom height field, right-click, then choose inspect element.

Note that you also have to delete all the page breaks in your original document otherwise no data will render after the first one.

Json.NET serialize object with root name

You can easily create your own serializer

var car = new Car() { Name = "Ford", Owner = "John Smith" };
string json = Serialize(car);

string Serialize<T>(T o)
{
    var attr = o.GetType().GetCustomAttribute(typeof(JsonObjectAttribute)) as JsonObjectAttribute;

    var jv = JValue.FromObject(o);

    return new JObject(new JProperty(attr.Title, jv)).ToString();
}

Call a global variable inside module

You need to tell the compiler it has been declared:

declare var bootbox: any;

If you have better type information you can add that too, in place of any.

Click a button with XPath containing partial id and title in Selenium IDE

Now that you have provided your HTML sample, we're able to see that your XPath is slightly wrong. While it's valid XPath, it's logically wrong.

You've got:

//*[contains(@id, 'ctl00_btnAircraftMapCell')]//*[contains(@title, 'Select Seat')]

Which translates into:

Get me all the elements that have an ID that contains ctl00_btnAircraftMapCell. Out of these elements, get any child elements that have a title that contains Select Seat.

What you actually want is:

//a[contains(@id, 'ctl00_btnAircraftMapCell') and contains(@title, 'Select Seat')]

Which translates into:

Get me all the anchor elements that have both: an id that contains ctl00_btnAircraftMapCell and a title that contains Select Seat.

How can I select random files from a directory in bash?

I use this: it uses temporary file but goes deeply in a directory until it find a regular file and return it.

# find for a quasi-random file in a directory tree:

# directory to start search from:
ROOT="/";  

tmp=/tmp/mytempfile    
TARGET="$ROOT"
FILE=""; 
n=
r=
while [ -e "$TARGET" ]; do 
    TARGET="$(readlink -f "${TARGET}/$FILE")" ; 
    if [ -d "$TARGET" ]; then
      ls -1 "$TARGET" 2> /dev/null > $tmp || break;
      n=$(cat $tmp | wc -l); 
      if [ $n != 0 ]; then
        FILE=$(shuf -n 1 $tmp)
# or if you dont have/want to use shuf:
#       r=$(($RANDOM % $n)) ; 
#       FILE=$(tail -n +$(( $r + 1 ))  $tmp | head -n 1); 
      fi ; 
    else
      if [ -f "$TARGET"  ] ; then
        rm -f $tmp
        echo $TARGET
        break;
      else 
        # is not a regular file, restart:
        TARGET="$ROOT"
        FILE=""
      fi
    fi
done;

How to switch position of two items in a Python list?

I am not an expert in python but you could try: say

i = (1,2)

res = lambda i: (i[1],i[0])
print 'res(1, 2) = {0}'.format(res(1, 2)) 

above would give o/p as:

res(1, 2) = (2,1)

Copy files to network computers on windows command line

Below command will work in command prompt:

copy c:\folder\file.ext \\dest-machine\destfolder /Z /Y

To Copy all files:

copy c:\folder\*.* \\dest-machine\destfolder /Z /Y

Calling an executable program using awk

There are several ways.

  1. awk has a system() function that will run a shell command:

    system("cmd")

  2. You can print to a pipe:

    print "blah" | "cmd"

  3. You can have awk construct commands, and pipe all the output to the shell:

    awk 'some script' | sh

Can you force a React component to rerender without calling setState?

forceUpdate(); method will work but it is advisable to use setState();

Angular2 module has no exported member

For me such issue occur when I had multiple export statements in single .ts file...

How can I merge two commits into one if I already started rebase?

Summary

The error message

Cannot 'squash' without a previous commit

means you likely attempted to “squash downward.” Git always squashes a newer commit into an older commit or “upward” as viewed on the interactive rebase todo list, that is into a commit on a previous line. Changing the command on your todo list’s very first line to squash will always produce this error as there is nothing for the first commit to squash into.

The Fix

First get back to where you started with

$ git rebase --abort

Say your history is

$ git log --pretty=oneline
a931ac7c808e2471b22b5bd20f0cad046b1c5d0d c
b76d157d507e819d7511132bdb5a80dd421d854f b
df239176e1a2ffac927d8b496ea00d5488481db5 a

That is, a was the first commit, then b, and finally c. After committing c we decide to squash b and c together:

(Note: Running git log pipes its output into a pager, less by default on most platforms. To quit the pager and return to your command prompt, press the q key.)

Running git rebase --interactive HEAD~2 gives you an editor with

pick b76d157 b
pick a931ac7 c

# Rebase df23917..a931ac7 onto df23917
#
# Commands:
#  p, pick = use commit
#  r, reword = use commit, but edit the commit message
#  e, edit = use commit, but stop for amending
#  s, squash = use commit, but meld into previous commit
#  f, fixup = like "squash", but discard this commit's log message
#
# If you remove a line here THAT COMMIT WILL BE LOST.
# However, if you remove everything, the rebase will be aborted.
#

(Notice that this todo list is in the reverse order as compared with the output of git log.)

Changing b’s pick to squash will result in the error you saw, but if instead you squash c into b (newer commit into the older or “squashing upward”) by changing the todo list to

pick   b76d157 b
squash a931ac7 c

and save-quitting your editor, you'll get another editor whose contents are

# This is a combination of 2 commits.
# The first commit's message is:

b

# This is the 2nd commit message:

c

When you save and quit, the contents of the edited file become commit message of the new combined commit:

$ git log --pretty=oneline
18fd73d3ce748f2a58d1b566c03dd9dafe0b6b4f b and c
df239176e1a2ffac927d8b496ea00d5488481db5 a

Note About Rewriting History

Interactive rebase rewrites history. Attempting to push to a remote that contains the old history will fail because it is not a fast-forward.

If the branch you rebased is a topic or feature branch in which you are working by yourself, no big deal. Pushing to another repository will require the --force option, or alternatively you may be able, depending on the remote repository’s permissions, to first delete the old branch and then push the rebased version. Examples of those commands that will potentially destroy work is outside the scope of this answer.

Rewriting already-published history on a branch in which you are working with other people without very good reason such as leaking a password or other sensitive details forces work onto your collaborators and is antisocial and will annoy other developers. The “Recovering From an Upstream Rebase” section in the git rebase documentation explains, with added emphasis.

Rebasing (or any other form of rewriting) a branch that others have based work on is a bad idea: anyone downstream of it is forced to manually fix their history. This section explains how to do the fix from the downstream’s point of view. The real fix, however, would be to avoid rebasing the upstream in the first place.

What is ViewModel in MVC?

A lot of big examples, let me explain in clear and crispy way.

ViewModel = Model that is created to serve the view.

ASP.NET MVC view can't have more than one model so if we need to display properties from more than one models into the view, it is not possible. ViewModel serves this purpose.

View Model is a model class that can hold only those properties that is required for a view. It can also contains properties from more than one entities (tables) of the database. As the name suggests, this model is created specific to the View requirements.

Few examples of View Models are below

  • To list data from more than entities in a view page – we can create a View model and have properties of all the entities for which we want to list data. Join those database entities and set View model properties and return to the View to show data of different entities in one tabular form
  • View model may define only specific fields of a single entity that is required for the View.

ViewModel can also be used to insert, update records into more than one entities however the main use of ViewModel is to display columns from multiple entities (model) into a single view.

The way of creating ViewModel is same as creating Model, the way of creating view for the Viewmodel is same as creating view for Model.

Here is a small example of List data using ViewModel.

Hope this will be useful.

Get first 100 characters from string, respecting full words

Yes, there is. This is a function I borrowed from a user on a different forums a a few years back, so I can't take credit for it.

//truncate a string only at a whitespace (by nogdog)
function truncate($text, $length) {
   $length = abs((int)$length);
   if(strlen($text) > $length) {
      $text = preg_replace("/^(.{1,$length})(\s.*|$)/s", '\\1...', $text);
   }
   return($text);
}

Note that it automatically adds ellipses, if you don't want that just use '\\1' as the second parameter for the preg_replace call.

Can't get value of input type="file"?

You can't set the value of a file input in the markup, like you did with value="123".

This example shows that it really works: http://jsfiddle.net/marcosfromero/7bUba/

Android Color Picker

If you want a fragment solution, I have made a fork of android-color-picker where DialogFragment is used and is re-created on configuration change. Here's the link: https://github.com/lomza/android-color-picker

Set time to 00:00:00

Here are couple of utility functions I use to do just this.

/**
 * sets all the time related fields to ZERO!
 *
 * @param date
 *
 * @return Date with hours, minutes, seconds and ms set to ZERO!
 */
public static Date zeroTime( final Date date )
{
    return DateTimeUtil.setTime( date, 0, 0, 0, 0 );
}

/**
 * Set the time of the given Date
 *
 * @param date
 * @param hourOfDay
 * @param minute
 * @param second
 * @param ms
 *
 * @return new instance of java.util.Date with the time set
 */
public static Date setTime( final Date date, final int hourOfDay, final int minute, final int second, final int ms )
{
    final GregorianCalendar gc = new GregorianCalendar();
    gc.setTime( date );
    gc.set( Calendar.HOUR_OF_DAY, hourOfDay );
    gc.set( Calendar.MINUTE, minute );
    gc.set( Calendar.SECOND, second );
    gc.set( Calendar.MILLISECOND, ms );
    return gc.getTime();
}

jsPDF multi page PDF with HTML renderer

I found the solution on this page: https://github.com/MrRio/jsPDF/issues/434 From the user: wangzhixuan

I copy the solution here: // suppose your picture is already in a canvas

      var imgData = canvas.toDataURL('image/png');

      /*
      Here are the numbers (paper width and height) that I found to work. 
      It still creates a little overlap part between the pages, but good enough for me.
      if you can find an official number from jsPDF, use them.
      */
      var imgWidth = 210; 
      var pageHeight = 295;  
      var imgHeight = canvas.height * imgWidth / canvas.width;
      var heightLeft = imgHeight;

      var doc = new jsPDF('p', 'mm');
      var position = 0;

      doc.addImage(imgData, 'PNG', 0, position, imgWidth, imgHeight);
      heightLeft -= pageHeight;

      while (heightLeft >= 0) {
        position = heightLeft - imgHeight;
        doc.addPage();
        doc.addImage(imgData, 'PNG', 0, position, imgWidth, imgHeight);
        heightLeft -= pageHeight;
      }
      doc.save( 'file.pdf');?

jQuery function to get all unique elements from an array?

Just use this code as the basis of a simple JQuery plugin.

$.extend({
    distinct : function(anArray) {
       var result = [];
       $.each(anArray, function(i,v){
           if ($.inArray(v, result) == -1) result.push(v);
       });
       return result;
    }
});

Use as so:

$.distinct([0,1,2,2,3]);

What is %2C in a URL?

Check out http://www.asciitable.com/

Look at the Hx, (Hex) column; 2C maps to ,

Any unusual encoding can be checked this way

+----+-----+----+-----+----+-----+----+-----+
| Hx | Chr | Hx | Chr | Hx | Chr | Hx | Chr |
+----+-----+----+-----+----+-----+----+-----+
| 00 | NUL | 20 | SPC | 40 |  @  | 60 |  `  |
| 01 | SOH | 21 |  !  | 41 |  A  | 61 |  a  |
| 02 | STX | 22 |  "  | 42 |  B  | 62 |  b  |
| 03 | ETX | 23 |  #  | 43 |  C  | 63 |  c  |
| 04 | EOT | 24 |  $  | 44 |  D  | 64 |  d  |
| 05 | ENQ | 25 |  %  | 45 |  E  | 65 |  e  |
| 06 | ACK | 26 |  &  | 46 |  F  | 66 |  f  |
| 07 | BEL | 27 |  '  | 47 |  G  | 67 |  g  |
| 08 | BS  | 28 |  (  | 48 |  H  | 68 |  h  |
| 09 | TAB | 29 |  )  | 49 |  I  | 69 |  i  |
| 0A | LF  | 2A |  *  | 4A |  J  | 6A |  j  |
| 0B | VT  | 2B |  +  | 4B |  K  | 6B |  k  |
| 0C | FF  | 2C |  ,  | 4C |  L  | 6C |  l  |
| 0D | CR  | 2D |  -  | 4D |  M  | 6D |  m  |
| 0E | SO  | 2E |  .  | 4E |  N  | 6E |  n  |
| 0F | SI  | 2F |  /  | 4F |  O  | 6F |  o  |
| 10 | DLE | 30 |  0  | 50 |  P  | 70 |  p  |
| 11 | DC1 | 31 |  1  | 51 |  Q  | 71 |  q  |
| 12 | DC2 | 32 |  2  | 52 |  R  | 72 |  r  |
| 13 | DC3 | 33 |  3  | 53 |  S  | 73 |  s  |
| 14 | DC4 | 34 |  4  | 54 |  T  | 74 |  t  |
| 15 | NAK | 35 |  5  | 55 |  U  | 75 |  u  |
| 16 | SYN | 36 |  6  | 56 |  V  | 76 |  v  |
| 17 | ETB | 37 |  7  | 57 |  W  | 77 |  w  |
| 18 | CAN | 38 |  8  | 58 |  X  | 78 |  x  |
| 19 | EM  | 39 |  9  | 59 |  Y  | 79 |  y  |
| 1A | SUB | 3A |  :  | 5A |  Z  | 7A |  z  |
| 1B | ESC | 3B |  ;  | 5B |  [  | 7B |  {  |
| 1C | FS  | 3C |  <  | 5C |  \  | 7C |  |  |
| 1D | GS  | 3D |  =  | 5D |  ]  | 7D |  }  |
| 1E | RS  | 3E |  >  | 5E |  ^  | 7E |  ~  |
| 1F | US  | 3F |  ?  | 5F |  _  | 7F | DEL |
+----+-----+----+-----+----+-----+----+-----+

Unable to get provider com.google.firebase.provider.FirebaseInitProvider

This should works:

Step1:

defaultConfig {
    applicationId "service.ingreens.com.gpsautoon"
    minSdkVersion 17
    targetSdkVersion 25
    versionCode 1
    versionName "1.0"
    multiDexEnabled true
    testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}

Step 2:

compile 'com.android.support:multidex:1.0.1'

Step 3: Take another class

public class MyApplication extends MultiDexApplication {
}

Step 4: Add this line on manifest

<application
    android:name="android.support.multidex.MultiDexApplication">
</application>

Best way to load module/class from lib folder in Rails 3?

If only certain files need access to the modules in lib, just add a require statement to the files that need it. For example, if one model needs to access one module, add:

require 'mymodule'

at the top of the model.rb file.

jQuery set checkbox checked

Worked for me:

$checkbok.prop({checked: true});

System.Data.SqlClient.SqlException: Invalid object name 'dbo.Projects'

Do you have access to the SQL Server you are querying? Can you see a Table or View called dbo.Projects there? If not, that would be a good place to look.

Linq to SQL creates an object map between the database and the application. If your new DLL that you're deploying doesn't match with the database anymore, then this is the sort of error you'd expect to get.

Do you perhaps have different database schemas between your development environment and the deployment environment?

What's the complete range for Chinese characters in Unicode?

The exact ranges for Chinese characters (except the extensions) are [\u2E80-\u2FD5\u3190-\u319f\u3400-\u4DBF\u4E00-\u9FCC\uF900-\uFAAD].

  1. [\u2e80-\u2fd5]

CJK Radicals Supplement is a Unicode block containing alternative, often positional, forms of the Kangxi radicals. They are used headers in dictionary indices and other CJK ideograph collections organized by radical-stroke.

  1. [\u3190-\u319f]

Kanbun is a Unicode block containing annotation characters used in Japanese copies of classical Chinese texts, to indicate reading order.

  1. [\u3400-\u4DBF]

CJK Unified Ideographs Extension-A is a Unicode block containing rare Han ideographs.

  1. [\u4E00-\u9FCC]

CJK Unified Ideographs is a Unicode block containing the most common CJK ideographs used in modern Chinese and Japanese.

  1. [\uF900-\uFAAD]

CJK Compatibility Ideographs is a Unicode block created to contain Han characters that were encoded in multiple locations in other established character encodings, in addition to their CJK Unified Ideographs assignments, in order to retain round-trip compatibility between Unicode and those encodings.

For the details please refer to here, and the extensions are provided in other answers.

What is event bubbling and capturing?

Bubbling

  Event propagate to the upto root element is **BUBBLING**.

Capturing

  Event propagate from body(root) element to eventTriggered Element is **CAPTURING**.

C# "internal" access modifier when doing unit testing

Keep using private by default. If a member shouldn't be exposed beyond that type, it shouldn't be exposed beyond that type, even to within the same project. This keeps things safer and tidier - when you're using the object, it's clearer which methods you're meant to be able to use.

Having said that, I think it's reasonable to make naturally-private methods internal for test purposes sometimes. I prefer that to using reflection, which is refactoring-unfriendly.

One thing to consider might be a "ForTest" suffix:

internal void DoThisForTest(string name)
{
    DoThis(name);
}

private void DoThis(string name)
{
    // Real implementation
}

Then when you're using the class within the same project, it's obvious (now and in the future) that you shouldn't really be using this method - it's only there for test purposes. This is a bit hacky, and not something I do myself, but it's at least worth consideration.

Directory index forbidden by Options directive

If you've been doing performance tuning, you might have removed mod_dir. Try putting it back and that might fix your issue.

How to return result of a SELECT inside a function in PostgreSQL?

Hi please check the below link

https://www.postgresql.org/docs/current/xfunc-sql.html

EX:

CREATE FUNCTION sum_n_product_with_tab (x int)
RETURNS TABLE(sum int, product int) AS $$
    SELECT $1 + tab.y, $1 * tab.y FROM tab;
$$ LANGUAGE SQL;

how to show lines in common (reverse diff)?

Just for information, i made a little tool for Windows doing the same thing than "grep -F -x -f file1 file2" (As i haven't found anything equivalent to this command on Windows)

Here it is : http://www.nerdzcore.com/?page=commonlines

Usage is "CommonLines inputFile1 inputFile2 outputFile"

Source code is also available (GPL)

How do I access previous promise results in a .then() chain?

ECMAScript Harmony

Of course, this problem was recognized by the language designers as well. They did a lot of work and the async functions proposal finally made it into

ECMAScript 8

You don't need a single then invocation or callback function anymore, as in an asynchronous function (that returns a promise when being called) you can simply wait for promises to resolve directly. It also features arbitrary control structures like conditions, loops and try-catch-clauses, but for the sake of convenience we don't need them here:

async function getExample() {
    var resultA = await promiseA(…);
    // some processing
    var resultB = await promiseB(…);
    // more processing
    return // something using both resultA and resultB
}

ECMAScript 6

While we were waiting for ES8, we already did use a very similar kind of syntax. ES6 came with generator functions, which allow breaking the execution apart in pieces at arbitrarily placed yield keywords. Those slices can be run after each other, independently, even asynchronously - and that's just what we do when we want to wait for a promise resolution before running the next step.

There are dedicated libraries (like co or task.js), but also many promise libraries have helper functions (Q, Bluebird, when, …) that do this async step-by-step execution for you when you give them a generator function that yields promises.

var getExample = Promise.coroutine(function* () {
//               ^^^^^^^^^^^^^^^^^ Bluebird syntax
    var resultA = yield promiseA(…);
    // some processing
    var resultB = yield promiseB(…);
    // more processing
    return // something using both resultA and resultB
});

This did work in Node.js since version 4.0, also a few browsers (or their dev editions) did support generator syntax relatively early.

ECMAScript 5

However, if you want/need to be backward-compatible you cannot use those without a transpiler. Both generator functions and async functions are supported by the current tooling, see for example the documentation of Babel on generators and async functions.

And then, there are also many other compile-to-JS languages that are dedicated to easing asynchronous programming. They usually use a syntax similar to await, (e.g. Iced CoffeeScript), but there are also others that feature a Haskell-like do-notation (e.g. LatteJs, monadic, PureScript or LispyScript).

Select multiple columns using Entity Framework

Here is a code sample:

var dataset = entities.processlists
    .Where(x => x.environmentID == environmentid && x.ProcessName == processname && x.RemoteIP == remoteip && x.CommandLine == commandlinepart)
    .Select(x => new PInfo 
                 { 
                      ServerName = x.ServerName, 
                      ProcessID = x.ProcessID, 
                      UserName = x.Username 
                 }) AsEnumerable().
               Select(y => new PInfo
               {
                   ServerName = y.ServerName,
                   ProcessID = y.ProcessID,
                   UserName = y.UserName 
               }).ToList();

What does "implements" do on a class?

Implements means that it takes on the designated behavior that the interface specifies. Consider the following interface:

public interface ISpeak
{
   public String talk();
}

public class Dog implements ISpeak
{
   public String talk()
   {
        return "bark!";
   }
}

public class Cat implements ISpeak
{
    public String talk()
    {
        return "meow!";
    }
}

Both the Cat and Dog class implement the ISpeak interface.

What's great about interfaces is that we can now refer to instances of this class through the ISpeak interface. Consider the following example:

  Dog dog = new Dog();
  Cat cat = new Cat();

  List<ISpeak> animalsThatTalk = new ArrayList<ISpeak>();

  animalsThatTalk.add(dog);
  animalsThatTalk.add(cat);

  for (ISpeak ispeak : animalsThatTalk)
  {
      System.out.println(ispeak.talk());
  }

The output for this loop would be:

bark!
meow!

Interface provide a means to interact with classes in a generic way based upon the things they do without exposing what the implementing classes are.

One of the most common interfaces used in Java, for example, is Comparable. If your object implements this interface, you can write an implementation that consumers can use to sort your objects.

For example:

public class Person implements Comparable<Person>
{
  private String firstName;
  private String lastName;

  // Getters/Setters

  public int compareTo(Person p)
  {
    return this.lastName.compareTo(p.getLastName());  
  }
}

Now consider this code:

//  Some code in other class

List<Person> people = getPeopleList();

Collections.sort(people);

What this code did was provide a natural ordering to the Person class. Because we implemented the Comparable interface, we were able to leverage the Collections.sort() method to sort our List of Person objects by its natural ordering, in this case, by last name.

Is there a vr (vertical rule) in html?

HTML has little to no vertical positioning due to typographic nature of content layout. Vertical Rule just doesn't fit its semantics.

How to sort an array of ints using a custom comparator?

If you don't want to copy the array (say it is very large), you might want to create a wrapper List<Integer> that can be used in a sort:

final int[] elements = {1, 2, 3, 4};
List<Integer> wrapper = new AbstractList<Integer>() {

        @Override
        public Integer get(int index) {
            return elements[index];
        }

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

        @Override
        public Integer set(int index, Integer element) {
            int v = elements[index];
            elements[index] = element;
            return v;
        }

    };

And now you can do a sort on this wrapper List using a custom comparator.

A monad is just a monoid in the category of endofunctors, what's the problem?

The answers here do an excellent job in defining both monoids and monads, however, they still don't seem to answer the question:

And on a less important note, is this true and if so could you give an explanation (hopefully one that can be understood by someone who doesn't have much Haskell experience)?

The crux of the matter that is missing here, is the different notion of "monoid", the so-called categorification more precisely -- the one of monoid in a monoidal category. Sadly Mac Lane's book itself makes it very confusing:

All told, a monad in X is just a monoid in the category of endofunctors of X, with product × replaced by composition of endofunctors and unit set by the identity endofunctor.

Main confusion

Why is this confusing? Because it does not define what is "monoid in the category of endofunctors" of X. Instead, this sentence suggests taking a monoid inside the set of all endofunctors together with the functor composition as binary operation and the identity functor as a monoidal unit. Which works perfectly fine and turns into a monoid any subset of endofunctors that contains the identity functor and is closed under functor composition.

Yet this is not the correct interpretation, which the book fails to make clear at that stage. A Monad f is a fixed endofunctor, not a subset of endofunctors closed under composition. A common construction is to use f to generate a monoid by taking the set of all k-fold compositions f^k = f(f(...)) of f with itself, including k=0 that corresponds to the identity f^0 = id. And now the set S of all these powers for all k>=0 is indeed a monoid "with product × replaced by composition of endofunctors and unit set by the identity endofunctor".

And yet:

  • This monoid S can be defined for any functor f or even literally for any self-map of X. It is the monoid generated by f.
  • The monoidal structure of S given by the functor composition and the identity functor has nothing do with f being or not being a monad.

And to make things more confusing, the definition of "monoid in monoidal category" comes later in the book as you can see from the table of contents. And yet understanding this notion is absolutely critical to understanding the connection with monads.

(Strict) monoidal categories

Going to Chapter VII on Monoids (which comes later than Chapter VI on Monads), we find the definition of the so-called strict monoidal category as triple (B, *, e), where B is a category, *: B x B-> B a bifunctor (functor with respect to each component with other component fixed) and e is a unit object in B, satisfying the associativity and unit laws:

(a * b) * c = a * (b * c)
a * e = e * a = a

for any objects a,b,c of B, and the same identities for any morphisms a,b,c with e replaced by id_e, the identity morphism of e. It is now instructive to observe that in our case of interest, where B is the category of endofunctors of X with natural transformations as morphisms, * the functor composition and e the identity functor, all these laws are satisfied, as can be directly verified.

What comes after in the book is the definition of the "relaxed" monoidal category, where the laws only hold modulo some fixed natural transformations satisfying so-called coherence relations, which is however not important for our cases of the endofunctor categories.

Monoids in monoidal categories

Finally, in section 3 "Monoids" of Chapter VII, the actual definition is given:

A monoid c in a monoidal category (B, *, e) is an object of B with two arrows (morphisms)

mu: c * c -> c
nu: e -> c

making 3 diagrams commutative. Recall that in our case, these are morphisms in the category of endofunctors, which are natural transformations corresponding to precisely join and return for a monad. The connection becomes even clearer when we make the composition * more explicit, replacing c * c by c^2, where c is our monad.

Finally, notice that the 3 commutative diagrams (in the definition of a monoid in monoidal category) are written for general (non-strict) monoidal categories, while in our case all natural transformations arising as part of the monoidal category are actually identities. That will make the diagrams exactly the same as the ones in the definition of a monad, making the correspondence complete.

Conclusion

In summary, any monad is by definition an endofunctor, hence an object in the category of endofunctors, where the monadic join and return operators satisfy the definition of a monoid in that particular (strict) monoidal category. Vice versa, any monoid in the monoidal category of endofunctors is by definition a triple (c, mu, nu) consisting of an object and two arrows, e.g. natural transformations in our case, satisfying the same laws as a monad.

Finally, note the key difference between the (classical) monoids and the more general monoids in monoidal categories. The two arrows mu and nu above are not anymore a binary operation and a unit in a set. Instead, you have one fixed endofunctor c. The functor composition * and the identity functor alone do not provide the complete structure needed for the monad, despite that confusing remark in the book.

Another approach would be to compare with the standard monoid C of all self-maps of a set A, where the binary operation is the composition, that can be seen to map the standard cartesian product C x C into C. Passing to the categorified monoid, we are replacing the cartesian product x with the functor composition *, and the binary operation gets replaced with the natural transformation mu from c * c to c, that is a collection of the join operators

join: c(c(T))->c(T)

for every object T (type in programming). And the identity elements in classical monoids, which can be identified with images of maps from a fixed one-point-set, get replaced with the collection of the return operators

return: T->c(T) 

But now there are no more cartesian products, so no pairs of elements and thus no binary operations.

LocalDate to java.util.Date and vice versa simplest conversion?

You can convert the java.util.Date object into a String object, which will format the date as yyyy-mm-dd.

LocalDate has a parse method that will convert it to a LocalDate object. The string must represent a valid date and is parsed using DateTimeFormatter.ISO_LOCAL_DATE.

Date to LocalDate

LocalDate.parse(Date.toString())

Java generics - why is "extends T" allowed but not "implements T"?

The answer is in here :

To declare a bounded type parameter, list the type parameter's name, followed by the extends keyword, followed by its upper bound […]. Note that, in this context, extends is used in a general sense to mean either extends (as in classes) or implements (as in interfaces).

So there you have it, it's a bit confusing, and Oracle knows it.

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

I used to use a class like this. The statusCode is set when there is an error with the error message set in message. Data is stored either in the Map or in a List as and when appropriate.

/**
* 
*/
package com.test.presentation.response;

import java.util.Collection;
import java.util.Map;

/**
 * A simple POJO to send JSON response to ajax requests. This POJO enables  us to
 * send messages and error codes with the actual objects in the application.
 * 
 * 
 */
@SuppressWarnings("rawtypes")
public class GenericResponse {

/**
 * An array that contains the actual objects
 */
private Collection rows;

/**
 * An Map that contains the actual objects
 */
private Map mapData;

/**
 * A String containing error code. Set to 1 if there is an error
 */
private int statusCode = 0;

/**
 * A String containing error message.
 */
private String message;

/**
 * An array that contains the actual objects
 * 
 * @return the rows
 */
public Collection getRows() {
    return rows;
}

/**
 * An array that contains the actual objects
 * 
 * @param rows
 *            the rows to set
 */
public void setRows(Collection rows) {
    this.rows = rows;
}

/**
 * An Map that contains the actual objects
 * 
 * @return the mapData
 */
public Map getMapData() {
    return mapData;
}

/**
 * An Map that contains the actual objects
 * 
 * @param mapData
 *            the mapData to set
 */
public void setMapData(Map mapData) {
    this.mapData = mapData;
}

/**
 * A String containing error code.
 * 
 * @return the errorCode
 */
public int getStatusCode() {
    return statusCode;
}

/**
 * A String containing error code.
 * 
 * @param errorCode
 *            the errorCode to set
 */
public void setStatusCode(int errorCode) {
    this.statusCode = errorCode;
}

/**
 * A String containing error message.
 * 
 * @return the errorMessage
 */
public String getMessage() {
    return message;
}

/**
 * A String containing error message.
 * 
 * @param errorMessage
 *            the errorMessage to set
 */
public void setMessage(String errorMessage) {
    this.message = errorMessage;
}

}

Hope this helps.

Reflection: How to Invoke Method with parameters

Change "methodInfo" to "classInstance", just like in the call with the null parameter array.

  result = methodInfo.Invoke(classInstance, parametersArray);

"FATAL: Module not found error" using modprobe

The reason is that modprobe looks into /lib/modules/$(uname -r) for the modules and therefore won't work with local file path. That's one of differences between modprobe and insmod.

Is it better to use std::memcpy() or std::copy() in terms to performance?

Just a minor addition: The speed difference between memcpy() and std::copy() can vary quite a bit depending on if optimizations are enabled or disabled. With g++ 6.2.0 and without optimizations memcpy() clearly wins:

Benchmark             Time           CPU Iterations
---------------------------------------------------
bm_memcpy            17 ns         17 ns   40867738
bm_stdcopy           62 ns         62 ns   11176219
bm_stdcopy_n         72 ns         72 ns    9481749

When optimizations are enabled (-O3), everything looks pretty much the same again:

Benchmark             Time           CPU Iterations
---------------------------------------------------
bm_memcpy             3 ns          3 ns  274527617
bm_stdcopy            3 ns          3 ns  272663990
bm_stdcopy_n          3 ns          3 ns  274732792

The bigger the array the less noticeable the effect gets, but even at N=1000 memcpy() is about twice as fast when optimizations aren't enabled.

Source code (requires Google Benchmark):

#include <string.h>
#include <algorithm>
#include <vector>
#include <benchmark/benchmark.h>

constexpr int N = 10;

void bm_memcpy(benchmark::State& state)
{
  std::vector<int> a(N);
  std::vector<int> r(N);

  while (state.KeepRunning())
  {
    memcpy(r.data(), a.data(), N * sizeof(int));
  }
}

void bm_stdcopy(benchmark::State& state)
{
  std::vector<int> a(N);
  std::vector<int> r(N);

  while (state.KeepRunning())
  {
    std::copy(a.begin(), a.end(), r.begin());
  }
}

void bm_stdcopy_n(benchmark::State& state)
{
  std::vector<int> a(N);
  std::vector<int> r(N);

  while (state.KeepRunning())
  {
    std::copy_n(a.begin(), N, r.begin());
  }
}

BENCHMARK(bm_memcpy);
BENCHMARK(bm_stdcopy);
BENCHMARK(bm_stdcopy_n);

BENCHMARK_MAIN()

/* EOF */

How to retrieve the current value of an oracle sequence without increment it?

My original reply was factually incorrect and I'm glad it was removed. The code below will work under the following conditions a) you know that nobody else modified the sequence b) the sequence was modified by your session. In my case, I encountered a similar issue where I was calling a procedure which modified a value and I'm confident the assumption is true.

SELECT mysequence.CURRVAL INTO v_myvariable FROM DUAL;

Sadly, if you didn't modify the sequence in your session, I believe others are correct in stating that the NEXTVAL is the only way to go.

Use NSInteger as array index

According to the error message, you declared myLoc as a pointer to an NSInteger (NSInteger *myLoc) rather than an actual NSInteger (NSInteger myLoc). It needs to be the latter.

How to use ternary operator in razor (specifically on HTML attributes)?

Addendum:

The important concept is that you are evaluating an expression in your Razor code. The best way to do this (if, for example, you are in a foreach loop) is using a generic method.

The syntax for calling a generic method in Razor is:

@(expression)

In this case, the expression is:

User.Identity.IsAuthenticated ? "auth" : "anon"

Therefore, the solution is:

@(User.Identity.IsAuthenticated ? "auth" : "anon")

This code can be used anywhere in Razor, not just for an html attribute.

See @Kyralessa 's comment for C# Razor Syntax Quick Reference (Phil Haack's blog).

How to use Jquery how to change the aria-expanded="false" part of a dom element (Bootstrap)?

Since the question asked for either jQuery or vanilla JS, here's an answer with vanilla JS.

I've added some CSS to the demo below to change the button's font color to red when its aria-expanded is set to true

_x000D_
_x000D_
const button = document.querySelector('button');_x000D_
_x000D_
button.addEventListener('click', () => {_x000D_
  button.ariaExpanded = !JSON.parse(button.ariaExpanded);_x000D_
})
_x000D_
button[aria-expanded="true"] {_x000D_
  color: red;_x000D_
}
_x000D_
<button type="button" aria-expanded="false">Click me!</button>
_x000D_
_x000D_
_x000D_

How to copy a dictionary and only edit the copy

You can also just make a new dictionary with a dictionary comprehension. This avoids importing copy.

dout = dict((k,v) for k,v in mydict.items())

Of course in python >= 2.7 you can do:

dout = {k:v for k,v in mydict.items()}

But for backwards compat., the top method is better.

NSPhotoLibraryUsageDescription key must be present in Info.plist to use camera roll

For camera access use:

<key>NSCameraUsageDescription</key>
<string>Camera Access Warning</string>

How can you export the Visual Studio Code extension list?

Generate a Windows command file (batch) for installing extensions:

for /F "tokens=*" %i in ('code --list-extensions')
   do @echo call code --install-extension %i >> install.cmd

How can you run a command in bash over and over until success?

You need to test $? instead, which is the exit status of the previous command. passwd exits with 0 if everything worked ok, and non-zero if the passwd change failed (wrong password, password mismatch, etc...)

passwd
while [ $? -ne 0 ]; do
    passwd
done

With your backtick version, you're comparing passwd's output, which would be stuff like Enter password and confirm password and the like.

How to set the default value of an attribute on a Laravel model

You should set default values in migrations:

$table->tinyInteger('role')->default(1);

mongodb: insert if not exists

1. Use Update.

Drawing from Van Nguyen's answer above, use update instead of save. This gives you access to the upsert option.

NOTE: This method overrides the entire document when found (From the docs)

var conditions = { name: 'borne' }   , update = { $inc: { visits: 1 }} , options = { multi: true };

Model.update(conditions, update, options, callback);

function callback (err, numAffected) {   // numAffected is the number of updated documents })

1.a. Use $set

If you want to update a selection of the document, but not the whole thing, you can use the $set method with update. (again, From the docs)... So, if you want to set...

var query = { name: 'borne' };  Model.update(query, ***{ name: 'jason borne' }***, options, callback)

Send it as...

Model.update(query, ***{ $set: { name: 'jason borne' }}***, options, callback)

This helps prevent accidentally overwriting all of your document(s) with { name: 'jason borne' }.

How to return a custom object from a Spring Data JPA GROUP BY query

I used custom DTO (interface) to map a native query to - the most flexible approach and refactoring-safe.

The problem I had with this - that surprisingly, the order of fields in the interface and the columns in the query matters. I got it working by ordering interface getters alphabetically and then ordering the columns in the query the same way.

What's the best way to calculate the size of a directory in .NET?

This it the best way to calculate the size of a directory. Only other way would still use recursion but be a bit easier to use and isn't as flexible.

float folderSize = 0.0f;
FileInfo[] files = Directory.GetFiles(folder, "*", SearchOption.AllDirectories);
foreach(FileInfo file in files) folderSize += file.Length;

How to write to a file, using the logging Python module?

An example of using logging.basicConfig rather than logging.fileHandler()

logging.basicConfig(filename=logname,
                            filemode='a',
                            format='%(asctime)s,%(msecs)d %(name)s %(levelname)s %(message)s',
                            datefmt='%H:%M:%S',
                            level=logging.DEBUG)

logging.info("Running Urban Planning")

self.logger = logging.getLogger('urbanGUI')

In order, the five parts do the following:

  1. set the output file (filename=logname)
  2. set it to append rather than overwrite (filemode='a')
  3. determine the format of the output message (format=...)
  4. determine the format of the output time (datefmt='%H:%M:%S')
  5. and determine the minimum message level it will accept (level=logging.DEBUG).

Loop through a comma-separated shell variable

Another solution not using IFS and still preserving the spaces:

$ var="a bc,def,ghij"
$ while read line; do echo line="$line"; done < <(echo "$var" | tr ',' '\n')
line=a bc
line=def
line=ghij

Where does Internet Explorer store saved passwords?

I found the answer. IE stores passwords in two different locations based on the password type:

  • Http-Auth: %APPDATA%\Microsoft\Credentials, in encrypted files
  • Form-based: HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\IntelliForms\Storage2, encrypted with the url

From a very good page on NirSoft.com:

Starting from version 7.0 of Internet Explorer, Microsoft completely changed the way that passwords are saved. In previous versions (4.0 - 6.0), all passwords were saved in a special location in the Registry known as the "Protected Storage". In version 7.0 of Internet Explorer, passwords are saved in different locations, depending on the type of password. Each type of passwords has some limitations in password recovery:

  • AutoComplete Passwords: These passwords are saved in the following location in the Registry: HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\IntelliForms\Storage2 The passwords are encrypted with the URL of the Web sites that asked for the passwords, and thus they can only be recovered if the URLs are stored in the history file. If you clear the history file, IE PassView won't be able to recover the passwords until you visit again the Web sites that asked for the passwords. Alternatively, you can add a list of URLs of Web sites that requires user name/password into the Web sites file (see below).

  • HTTP Authentication Passwords: These passwords are stored in the Credentials file under Documents and Settings\Application Data\Microsoft\Credentials, together with login passwords of LAN computers and other passwords. Due to security limitations, IE PassView can recover these passwords only if you have administrator rights.

In my particular case it answers the question of where; and I decided that I don't want to duplicate that. I'll continue to use CredRead/CredWrite, where the user can manage their passwords from within an established UI system in Windows.

What does "#include <iostream>" do?

In order to read or write to the standard input/output streams you need to include it.

int main( int argc, char * argv[] )
{
    std::cout << "Hello World!" << std::endl;
    return 0;
}

That program will not compile unless you add #include <iostream>

The second line isn't necessary

using namespace std;

What that does is tell the compiler that symbol names defined in the std namespace are to be brought into your program's scope, so you can omit the namespace qualifier, and write for example

#include <iostream>
using namespace std;
int main( int argc, char * argv[] )
{
    cout << "Hello World!" << endl;
    return 0;
}

Notice you no longer need to refer to the output stream with the fully qualified name std::cout and can use the shorter name cout.

I personally don't like bringing in all symbols in the namespace of a header file... I'll individually select the symbols I want to be shorter... so I would do this:

#include <iostream>
using std::cout;
using std::endl;

int main( int argc, char * argv[] )
{
    cout << "Hello World!" << endl;
    return 0;
}

But that is a matter of personal preference.

Is it possible to override / remove background: none!important with jQuery?

Why does not it work? Because the background CSS with background:none!important has one #ID

A CSS selector file that contains an #id will always have a higher value than one .class

If you want to work, you need add #id on your .image-list li like this:

#an-element .image-list li {
    display: inline-block;
    background-image: url("http://placekitten.com/150/50")!important;
    padding: 1em;
    border: 1px solid blue;
}

result here

What's the difference between "git reset" and "git checkout"?

One simple use case when reverting change:
1. Use reset if you want to undo staging of a modified file.
2. Use checkout if you want to discard changes to unstaged file/s.

getFilesDir() vs Environment.getDataDirectory()

From the HERE and HERE

public File getFilesDir ()

Returns the absolute path to the directory on the filesystem where files created with openFileOutput(String, int) are stored.

public static File getExternalStorageDirectory ()

Return the primary external storage directory. This directory may not currently be accessible if it has been mounted by the user on their computer, has been removed from the device, or some other problem has happened. You can determine its current state with getExternalStorageState().

Note: don't be confused by the word "external" here. This directory can better be thought as media/shared storage. It is a filesystem that can hold a relatively large amount of data and that is shared across all applications (does not enforce permissions). Traditionally this is an SD card, but it may also be implemented as built-in storage in a device that is distinct from the protected internal storage and can be mounted as a filesystem on a computer.

On devices with multiple users (as described by UserManager), each user has their own isolated external storage. Applications only have access to the external storage for the user they're running as.

If you want to get your application path use getFilesDir() which will give you path /data/data/your package/files

You can get the path using the Environment var of your data/package using the

getExternalFilesDir(Environment.getDataDirectory().getAbsolutePath()).getAbsolutePath(); which will return the path from the root directory of your external storage as /storage/sdcard/Android/data/your pacakge/files/data

To access the external resources you have to provide the permission of WRITE_EXTERNAL_STORAGE and READ_EXTERNAL_STORAGE in your manifest.

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

Check out the Best Documentation to get the paths of direcorty

Can I call a base class's virtual function if I'm overriding it?

Yes,

class Bar : public Foo
{
    ...

    void printStuff()
    {
        Foo::printStuff();
    }
};

It is the same as super in Java, except it allows calling implementations from different bases when you have multiple inheritance.

class Foo {
public:
    virtual void foo() {
        ...
    }
};

class Baz {
public:
    virtual void foo() {
        ...
    }
};

class Bar : public Foo, public Baz {
public:
    virtual void foo() {
        // Choose one, or even call both if you need to.
        Foo::foo();
        Baz::foo();
    }
};

Show hide fragment in android

Try this:

MapFragment mapFragment = (MapFragment)getFragmentManager().findFragmentById(R.id.mapview);
mapFragment.getView().setVisibility(View.GONE);

Why is Python running my module when I import it, and how do I stop it?

There was a Python enhancement proposal PEP 299 which aimed to replace if __name__ == '__main__': idiom with def __main__:, but it was rejected. It's still a good read to know what to keep in mind when using if __name__ = '__main__':.

How do I get data from a table?

This is how I accomplished reading a table in javascript. Basically I drilled down into the rows and then I was able to drill down into the individual cells for each row. This should give you an idea

//gets table
var oTable = document.getElementById('myTable');

//gets rows of table
var rowLength = oTable.rows.length;

//loops through rows    
for (i = 0; i < rowLength; i++){

   //gets cells of current row
   var oCells = oTable.rows.item(i).cells;

   //gets amount of cells of current row
   var cellLength = oCells.length;

   //loops through each cell in current row
   for(var j = 0; j < cellLength; j++){
      /* get your cell info here */
      /* var cellVal = oCells.item(j).innerHTML; */
   }
}

UPDATED - TESTED SCRIPT

<table id="myTable">
    <tr>
        <td>A1</td>
        <td>A2</td>
        <td>A3</td>
    </tr>
    <tr>
        <td>B1</td>
        <td>B2</td>
        <td>B3</td>
    </tr>
</table>
<script>
    //gets table
    var oTable = document.getElementById('myTable');

    //gets rows of table
    var rowLength = oTable.rows.length;

    //loops through rows    
    for (i = 0; i < rowLength; i++){

      //gets cells of current row  
       var oCells = oTable.rows.item(i).cells;

       //gets amount of cells of current row
       var cellLength = oCells.length;

       //loops through each cell in current row
       for(var j = 0; j < cellLength; j++){

              // get your cell info here

              var cellVal = oCells.item(j).innerHTML;
              alert(cellVal);
           }
    }
</script>

efficient way to implement paging

LinqToSql will automatically convert a .Skip(N1).Take(N2) into the TSQL syntax for you. In fact, every "query" you do in Linq, is actually just creating a SQL query for you in the background. To test this, just run SQL Profiler while your application is running.

The skip/take methodology has worked very well for me, and others from what I read.

Out of curiosity, what type of self-paging query do you have, that you believe is more efficient than Linq's skip/take?

How to set the From email address for mailx command?

The package nail provides an enhanced mailx like interface. It includes the -r option.

On Centos 5 installing the package mailx gives you a program called mail, which doesn't support the mailx options.

How to generate an entity-relationship (ER) diagram using Oracle SQL Developer

I'm running SQL Developer 17.2.0.188 build 188.1159 which does indeed contain data modeling capability. I just created a relational model diagram via the menu: File->Data Modeler->Import->Data Dictionary....

I also have the stand-alone Data Modeler, which does the same thing.

As the Data Modeler tutorial states:

Figure 4: Relational model and diagram for HR

The diagram you’ve generated is not an ERD. Logical models are higher abstractions. An ERD represents entities and their attributes and relations, whereas a relational or physical model represents tables, columns, and foreign keys."

A connection was successfully established with the server, but then an error occurred during the login process. (Error Number: 233)

To add on top of @Pranav Singh and @Rahul Tripathi answer. After doing all the mentioned by those 2 users, my .net app still wasnt connecting to the database. My solution was.

Open Sql Server Configuration Manager, go to Network configuration of SQL SERVER, click on protocols, right click on TCP/IP and select enabled. I also right clicked on it opened properties, Ip directions, and scrolled to the bottom (IPAII , and there in TCP Port, I did setup a port (1433 is supposed to be default))

How do you simulate Mouse Click in C#?

I have tried the code that Marcos posted and it didn't worked for me. Whatever i was given to the Y coordinate the cursor didn't moved on Y axis. The code below will work if you want the position of the cursor relative to the left-up corner of your desktop, not relative to your application.

    [DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall)]
    public static extern void mouse_event(long dwFlags, long dx, long dy, long cButtons, long dwExtraInfo);
    private const int MOUSEEVENTF_LEFTDOWN = 0x02;
    private const int MOUSEEVENTF_LEFTUP = 0x04;
    private const int MOUSEEVENTF_MOVE = 0x0001;

    public void DoMouseClick()
    {
        X = Cursor.Position.X;
        Y = Cursor.Position.Y;

        //move to coordinates
        pt = (Point)pc.ConvertFromString(X + "," + Y);
        Cursor.Position = pt;       

        //perform click            
        mouse_event(MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0);
        mouse_event(MOUSEEVENTF_LEFTUP, 0, 0, 0, 0);
    }

I only use mouse_event function to actually perform the click. You can give X and Y what coordinates you want, i used values from textbox:

            X = Convert.ToInt32(tbX.Text);
            Y = Convert.ToInt32(tbY.Text);

How to update a menu item shown in the ActionBar?

In Kotlin 1.2 simply call:

invalidateOptionsMenu()

and the onCreateOptionsMenu function will be called again.

How can I reverse a list in Python?

You can also use the bitwise complement of the array index to step through the array in reverse:

>>> array = [0, 10, 20, 40]
>>> [array[~i] for i, _ in enumerate(array)]
[40, 20, 10, 0]

Whatever you do, don't do it this way ;)

What is the difference between match_parent and fill_parent?

They're the same thing (in API Level 8+). Use match_parent.

FILL_PARENT (renamed MATCH_PARENT in API Level 8 and higher), which means that the view wants to be as big as its parent (minus padding)

...

fill_parent: The view should be as big as its parent (minus padding). This constant is deprecated starting from API Level 8 and is replaced by match_parent.

http://developer.android.com/reference/android/view/ViewGroup.LayoutParams.html

PHP $_POST not working?

There is nothing wrong with your code. The problem is not visible form here.

  1. Check if after the submit, the script is called at all.

  2. Have a look at what is submitted: var_dump($_REQUEST)

Scroll / Jump to id without jQuery

Oxi's answer is just wrong.¹

What you want is:

var container = document.body,
element = document.getElementById('ElementID');
container.scrollTop = element.offsetTop;

Working example:

(function (){
  var i = 20, l = 20, html = '';
  while (i--){
    html += '<div id="DIV' +(l-i)+ '">DIV ' +(l-i)+ '</div>';
    html += '<a onclick="document.body.scrollTop=document.getElementById(\'DIV' +i+ '\').offsetTop">';
    html += '[ Scroll to #DIV' +i+ ' ]</a>';
    html += '<br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br /><br />';
  }
  document.write( html );
})();

¹ I haven't got enough reputation to comment on his answer

“Origin null is not allowed by Access-Control-Allow-Origin” error for request made by application running from a file:// URL

Make sure you are using the latest version of JQuery. We were facing this error for JQuery 1.10.2 and the error got resolved after using JQuery 1.11.1

Apache won't start in wamp

If Apache is installed as a Windows service, any errors will show up in the Windows System event log. To view the System event log, navigate to Windows Administrative Tools->Event Viewer and open the System log in the Windows Logs folder. Or, you can see the same errors by running httpd.exe at the command line. In my case, httpd.exe is located here: C:\Bitnami\wampstack-5.6.26-2\apache2\bin.

If there is a problem with starting Apache, most likely the problem can be fixed by editing the httpd.conf file located in the \apache2\conf folder. As already suggested, you can check the syntax of the httpd.conf file by running httpd.exe -t at the command line.

I found that the I had to

Change SetEnv PATH "C:\Bitnami\wampstack-5.6.26-2\apache2\bin;${PATH}" in httpd.conf

to

SetEnv PATH "C:\Bitnami\wampstack-5.6.26-2\apache2\bin;%PATH%"

Javascript array sort and unique

A way to use a custom sort function

//func has to return 0 in the case in which they are equal
sort_unique = function(arr,func) {
        func = func || function (a, b) {
            return a*1 - b*1;
        };
        arr = arr.sort(func);
        var ret = [arr[0]];
        for (var i = 1; i < arr.length; i++) {
            if (func(arr[i-1],arr[i]) != 0) 
                ret.push(arr[i]);
            }
        }
        return ret;
    }

Example: desc order for an array of objects

MyArray = sort_unique(MyArray , function(a,b){
            return  b.iterator_internal*1 - a.iterator_internal*1;
        });

Absolute and Flexbox in React Native

The first step would be to add

position: 'absolute',

then if you want the element full width, add

left: 0,
right: 0,

then, if you want to put the element in the bottom, add

bottom: 0,
// don't need set top: 0

if you want to position the element at the top, replace bottom: 0 by top: 0

How to get DATE from DATETIME Column in SQL?

Use Getdate()

 select sum(transaction_amount) from TransactionMaster
 where Card_No=' 123' and transaction_date =convert(varchar(10), getdate(), 102)

Concatenating date with a string in Excel

You can do it this simple way :

A1 = Mahi
A2 = NULL(blank)

Select A2 Right click on cell --> Format cells --> change to TEXT

Then put the date in A2 (A2 =31/07/1990)

Then concatenate it will work. No need of any formulae.

=CONCATENATE(A1,A2)

mahi31/07/1990

(This works on the empty cells ie.,Before entering the DATE value to cell you need to make it as TEXT).

How to create a sub array from another array in Java?

Use copyOfRange method from java.util.Arrays class:

int[] newArray = Arrays.copyOfRange(oldArray, startIndex, endIndex);

For more details:

Link to similar question

Facebook how to check if user has liked page and show content?

There is an article here that describes your problem

http://www.hyperarts.com/blog/facebook-fan-pages-content-for-fans-only-static-fbml/

    <fb:visible-to-connection>
       Fans will see this content.
       <fb:else>
           Non-fans will see this content.
       </fb:else>
    </fb:visible-to-connection>

Declaring an unsigned int in Java

It seems that you can handle the signing problem by doing a "logical AND" on the values before you use them:

Example (Value of byte[] header[0] is 0x86 ):

System.out.println("Integer "+(int)header[0]+" = "+((int)header[0]&0xff));

Result:

Integer -122 = 134

How to resolve git error: "Updates were rejected because the tip of your current branch is behind"

This worked for me:

git branch

Copy the current branch name to clipboard

git pull origin <paste-branch-name>
git push

Pandas dataframe fillna() only some columns in place

Sometimes this syntax wont work:

df[['col1','col2']] = df[['col1','col2']].fillna()

Use the following instead:

df['col1','col2']

How to create a directive with a dynamic template in AngularJS?

I have been in the same situation, my complete solution has been posted here

Basically I load a template in the directive in this way

var tpl = '' + 
    <div ng-if="maxLength" 
        ng-include="\'length.tpl.html\'">
    </div>' +
    '<div ng-if="required" 
        ng-include="\'required.tpl.html\'">
    </div>';

then according to the value of maxLength and required I can dynamically load one of the 2 templates, only one of them at a time is shown if necessary.

I heope it helps.

Gradients on UIView and UILabels On iPhone

You can use Core Graphics to draw the gradient, as pointed to in Mike's response. As a more detailed example, you could create a UIView subclass to use as a background for your UILabel. In that UIView subclass, override the drawRect: method and insert code similar to the following:

- (void)drawRect:(CGRect)rect 
{
    CGContextRef currentContext = UIGraphicsGetCurrentContext();

    CGGradientRef glossGradient;
    CGColorSpaceRef rgbColorspace;
    size_t num_locations = 2;
    CGFloat locations[2] = { 0.0, 1.0 };
    CGFloat components[8] = { 1.0, 1.0, 1.0, 0.35,  // Start color
         1.0, 1.0, 1.0, 0.06 }; // End color

    rgbColorspace = CGColorSpaceCreateDeviceRGB();
    glossGradient = CGGradientCreateWithColorComponents(rgbColorspace, components, locations, num_locations);

    CGRect currentBounds = self.bounds;
    CGPoint topCenter = CGPointMake(CGRectGetMidX(currentBounds), 0.0f);
    CGPoint midCenter = CGPointMake(CGRectGetMidX(currentBounds), CGRectGetMidY(currentBounds));
    CGContextDrawLinearGradient(currentContext, glossGradient, topCenter, midCenter, 0);

    CGGradientRelease(glossGradient);
    CGColorSpaceRelease(rgbColorspace); 
}

This particular example creates a white, glossy-style gradient that is drawn from the top of the UIView to its vertical center. You can set the UIView's backgroundColor to whatever you like and this gloss will be drawn on top of that color. You can also draw a radial gradient using the CGContextDrawRadialGradient function.

You just need to size this UIView appropriately and add your UILabel as a subview of it to get the effect you desire.

EDIT (4/23/2009): Per St3fan's suggestion, I have replaced the view's frame with its bounds in the code. This corrects for the case when the view's origin is not (0,0).

How to sort an STL vector?

A pointer-to-member allows you to write a single comparator, which can work with any data member of your class:

#include <algorithm>
#include <vector>
#include <string>
#include <iostream>

template <typename T, typename U>
struct CompareByMember {
    // This is a pointer-to-member, it represents a member of class T
    // The data member has type U
    U T::*field;
    CompareByMember(U T::*f) : field(f) {}
    bool operator()(const T &lhs, const T &rhs) {
        return lhs.*field < rhs.*field;
    }
};

struct Test {
    int a;
    int b;
    std::string c;
    Test(int a, int b, std::string c) : a(a), b(b), c(c) {}
};

// for convenience, this just lets us print out a Test object
std::ostream &operator<<(std::ostream &o, const Test &t) {
    return o << t.c;
}

int main() {
    std::vector<Test> vec;
    vec.push_back(Test(1, 10, "y"));
    vec.push_back(Test(2, 9, "x"));

    // sort on the string field
    std::sort(vec.begin(), vec.end(), 
        CompareByMember<Test,std::string>(&Test::c));
    std::cout << "sorted by string field, c: ";
    std::cout << vec[0] << " " << vec[1] << "\n";

    // sort on the first integer field
    std::sort(vec.begin(), vec.end(), 
        CompareByMember<Test,int>(&Test::a));
    std::cout << "sorted by integer field, a: ";
    std::cout << vec[0] << " " << vec[1] << "\n";

    // sort on the second integer field
    std::sort(vec.begin(), vec.end(), 
        CompareByMember<Test,int>(&Test::b));
    std::cout << "sorted by integer field, b: ";
    std::cout << vec[0] << " " << vec[1] << "\n";
}

Output:

sorted by string field, c: x y
sorted by integer field, a: y x
sorted by integer field, b: x y

Parsing command-line arguments in C

Tooting my own horn if I may, I'd also like to suggest taking a look at an option parsing library that I've written: dropt.

  • It's a C library (with a C++ wrapper if desired).
  • It's lightweight.
  • It's extensible (custom argument types can be easily added and have equal footing with built-in argument types).
  • It should be very portable (it's written in standard C) with no dependencies (other than the C standard library).
  • It has a very unrestrictive license (zlib/libpng).

One feature that it offers that many others don't is the ability to override earlier options. For example, if you have a shell alias:

alias bar="foo --flag1 --flag2 --flag3"

and you want to use bar but with--flag1 disabled, it allows you to do:

bar --flag1=0

Use Ant for running program with command line arguments

Extending Richard Cook's answer.

Here's the ant task to run any program (including, but not limited to Java programs):

<target name="run">
   <exec executable="name-of-executable">
      <arg value="${arg0}"/>
      <arg value="${arg1}"/>
   </exec>
</target>

Here's the task to run a Java program from a .jar file:

<target name="run-java">
   <java jar="path for jar">
      <arg value="${arg0}"/>
      <arg value="${arg1}"/>
   </java>
</target>

You can invoke either from the command line like this:

ant -Darg0=Hello -Darg1=World run

Make sure to use the -Darg syntax; if you ran this:

ant run arg0 arg1

then ant would try to run targets arg0 and arg1.

Where does Console.WriteLine go in ASP.NET?

In an ASP.NET application, I think it goes to the Output or Console window which is visible during debugging.

git commit error: pathspec 'commit' did not match any file(s) known to git

The command line arguments are separated by space. If you want provide an argument with a space in it, you should quote it. So use git commit -m "initial commit".

Design Documents (High Level and Low Level Design Documents)

High-Level Design (HLD) involves decomposing a system into modules, and representing the interfaces & invocation relationships among modules. An HLD is referred to as software architecture.

LLD, also known as a detailed design, is used to design internals of the individual modules identified during HLD i.e. data structures and algorithms of the modules are designed and documented.

Now, HLD and LLD are actually used in traditional Approach (Function-Oriented Software Design) whereas, in OOAD, the system is seen as a set of objects interacting with each other.

As per the above definitions, a high-level design document will usually include a high-level architecture diagram depicting the components, interfaces, and networks that need to be further specified or developed. The document may also depict or otherwise refer to work flows and/or data flows between component systems.

Class diagrams with all the methods and relations between classes come under LLD. Program specs are covered under LLD. LLD describes each and every module in an elaborate manner so that the programmer can directly code the program based on it. There will be at least 1 document for each module. The LLD will contain - a detailed functional logic of the module in pseudo code - database tables with all elements including their type and size - all interface details with complete API references(both requests and responses) - all dependency issues - error message listings - complete inputs and outputs for a module.

How to change the blue highlight color of a UITableViewCell?

UITableViewCell has three default selection styles:-

  1. Blue
  2. Gray
  3. None

Implementation is as follows:-

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *) indexPath {

     [cell setSelectionStyle:UITableViewCellSelectionStyleNone];       
}

Excel formula to display ONLY month and year?

Try the formula

=TEXT(TODAY(),"MMYYYY")

Troubleshooting "Warning: session_start(): Cannot send session cache limiter - headers already sent"

I had the same issue, but my solution wasn't as obvious as the suggested ones. It turned out that my php-file was written in UTF-8, which caused issues. I copy/pasted the content of the entire file into a new php-file (Notepad++ tells me this is written in ANSI rather than UTF-8), and now it work flawlessly.

The AWS Access Key Id does not exist in our records

If you get this error in an Amplify project, check that "awsConfigFilePath" is not configured in amplify/.config/local-aws-info.json

In my case I had to remove it, so my environment looked like the following:

{
  // **INCORRECT**
  // This will not use your profile in ~/.aws/credentials, but instead the
  // specified config file path
  // "dev": {
  //  "configLevel": "project",
  //  "useProfile": false,
  //  "awsConfigFilePath": "/Users/dev1/.amplify/awscloudformation/cEclTB7ddy"
  // },
  // **CORRECT**
  "dev": {
    "configLevel": "project",
    "useProfile": true,
    "profileName": "default",
  }
}

MVC Return Partial View as JSON

Instead of RenderViewToString I prefer a approach like

return Json(new { Url = Url.Action("Evil", model) });

then you can catch the result in your javascript and do something like

success: function(data) {
    $.post(data.Url, function(partial) { 
        $('#IdOfDivToUpdate').html(partial);
    });
}

Tri-state Check box in HTML?

There's a simple JavaScript tri-state input field implementation at https://github.com/supernifty/tristate-checkbox

Find the most common element in a list

If they are not hashable, you can sort them and do a single loop over the result counting the items (identical items will be next to each other). But it might be faster to make them hashable and use a dict.

def most_common(lst):
    cur_length = 0
    max_length = 0
    cur_i = 0
    max_i = 0
    cur_item = None
    max_item = None
    for i, item in sorted(enumerate(lst), key=lambda x: x[1]):
        if cur_item is None or cur_item != item:
            if cur_length > max_length or (cur_length == max_length and cur_i < max_i):
                max_length = cur_length
                max_i = cur_i
                max_item = cur_item
            cur_length = 1
            cur_i = i
            cur_item = item
        else:
            cur_length += 1
    if cur_length > max_length or (cur_length == max_length and cur_i < max_i):
        return cur_item
    return max_item

Using XPATH to search text containing &nbsp;

I cannot get a match using Xpather, but the following worked for me with plain XML and XSL files in Microsoft's XML Notepad:

<xsl:value-of select="count(//td[text()='&nbsp;'])" />

The value returned is 1, which is the correct value in my test case.

However, I did have to declare nbsp as an entity within my XML and XSL using the following:

<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#160;"> ]>

I'm not sure if that helps you, but I was able to actually find nbsp using an XPath expression.

Edit: My code sample actually contains the characters '&nbsp;' but the JavaScript syntax highlight converts it to the space character. Don't be mislead!

"detached entity passed to persist error" with JPA/EJB code

remove

user.setId(1);

because it is auto generate on the DB, and continue with persist command.

How to validate a file upload field using Javascript/jquery

My function will check if the user has selected the file or not and you can also check whether you want to allow that file extension or not.

Try this:

<input type="file" name="fileUpload" onchange="validate_fileupload(this.value);">

function validate_fileupload(fileName)
{
    var allowed_extensions = new Array("jpg","png","gif");
    var file_extension = fileName.split('.').pop().toLowerCase(); // split function will split the filename by dot(.), and pop function will pop the last element from the array which will give you the extension as well. If there will be no extension then it will return the filename.

    for(var i = 0; i <= allowed_extensions.length; i++)
    {
        if(allowed_extensions[i]==file_extension)
        {
            return true; // valid file extension
        }
    }

    return false;
}

How to list all available Kafka brokers in a cluster?

Using Confluent's REST Proxy API v3:

curl -X GET -H "Accept: application/vnd.api+json" localhost:8082/v3/clusters

where localhost:8082 is Kafka Proxy address.

Side-by-side plots with ggplot2

Using the patchwork package, you can simply use + operator:

library(ggplot2)
library(patchwork)

p1 <- ggplot(mtcars) + geom_point(aes(mpg, disp))
p2 <- ggplot(mtcars) + geom_boxplot(aes(gear, disp, group = gear))


p1 + p2

patchwork

Other operators include / to stack plots to place plots side by side, and () to group elements. For example you can configure a top row of 3 plots and a bottom row of one plot with (p1 | p2 | p3) /p. For more examples, see the package documentation.

Get Absolute Position of element within the window in wpf

Add this method to a static class:

 public static Rect GetAbsolutePlacement(this FrameworkElement element, bool relativeToScreen = false)
    {
        var absolutePos = element.PointToScreen(new System.Windows.Point(0, 0));
        if (relativeToScreen)
        {
            return new Rect(absolutePos.X, absolutePos.Y, element.ActualWidth, element.ActualHeight);
        }
        var posMW = Application.Current.MainWindow.PointToScreen(new System.Windows.Point(0, 0));
        absolutePos = new System.Windows.Point(absolutePos.X - posMW.X, absolutePos.Y - posMW.Y);
        return new Rect(absolutePos.X, absolutePos.Y, element.ActualWidth, element.ActualHeight);
    }

Set relativeToScreen paramater to true for placement from top left corner of whole screen or to false for placement from top left corner of application window.

Toggle show/hide on click with jQuery

You can use this code for toggle your element var ele = jQuery("yourelementid"); ele.slideToggle('slow'); this will work for you :)

How to set up a PostgreSQL database in Django

This may seem a bit lengthy, but it worked for me without any error.

At first, Install phppgadmin from Ubuntu Software Center.

Then run these steps in terminal.

sudo apt-get install libpq-dev python-dev
pip install psycopg2
sudo apt-get install postgresql postgresql-contrib phppgadmin

Start the apache server

sudo service apache2 start

Now run this too in terminal, to edit the apache file.

sudo gedit /etc/apache2/apache2.conf

Add the following line to the opened file:

Include /etc/apache2/conf.d/phppgadmin

Now reload apache. Use terminal.

sudo /etc/init.d/apache2 reload

Now you will have to create a new database. Login as 'postgres' user. Continue in terminal.

sudo su - postgres

In case you have trouble with the password of 'postgres', you can change it using the answer here https://stackoverflow.com/a/12721020/1990793 and continue with the steps.

Now create a database

createdb <db_name>

Now create a new user to login to phppgadmin later, providing a new password.

createuser -P <new_user>

Now your postgressql has been setup, and you can go to:

http://localhost/phppgadmin/

and login using the new user you've created, in order to view the database.

Wait for all promises to resolve

Recently had this problem but with unkown number of promises.Solved using jQuery.map().

function methodThatChainsPromises(args) {

    //var args = [
    //    'myArg1',
    //    'myArg2',
    //    'myArg3',
    //];

    var deferred = $q.defer();
    var chain = args.map(methodThatTakeArgAndReturnsPromise);

    $q.all(chain)
    .then(function () {
        $log.debug('All promises have been resolved.');
        deferred.resolve();
    })
    .catch(function () {
        $log.debug('One or more promises failed.');
        deferred.reject();
    });

    return deferred.promise;
}

Loaded nib but the 'view' outlet was not set

To anyone that is using an xib method to create a UIView and having this problem, you will notice that you won't have the "view" outlet under the connections inspector menu. But if you set the File's Owners custom class to a UIViewController and then you will see the "view" outlet, which you can just CMND connect an outlet to the CustomView.

Android Studio - mergeDebugResources exception

My problem solve this one

compile fileTree(dir: 'libs', include: ['*.jar'])

to

provided fileTree(dir: 'libs', include: ['*.jar'])

Why is there extra padding at the top of my UITableView with style UITableViewStyleGrouped in iOS7

I have just removed UITableView from Interface Builder, created it once again and strange 35px gone away.

It seems that it there is a strange bug in Interface Builder.

How can I know if Object is String type object?

Either use instanceof or method Class.isAssignableFrom(Class<?> cls).

WSDL validator?

If you would to validate WSDL programatically then you use WSDL Validator out of eclipse. http://wiki.eclipse.org/Using_the_WSDL_Validator_Outside_of_Eclipse should help or try this tool Graphical WSDL 1.1/2.0 editor.

How do I unset an element in an array in javascript?

Don't use delete as it won't remove an element from an array it will only set it as undefined, which will then not be reflected correctly in the length of the array.

If you know the key you should use splice i.e.

myArray.splice(key, 1);

For someone in Steven's position you can try something like this:

for (var key in myArray) {
    if (key == 'bar') {
        myArray.splice(key, 1);
    }
}

or

for (var key in myArray) {
    if (myArray[key] == 'bar') {
        myArray.splice(key, 1);
    }
}

Reading a huge .csv file

what worked for me was and is superfast is

import pandas as pd
import dask.dataframe as dd
import time
t=time.clock()
df_train = dd.read_csv('../data/train.csv', usecols=[col1, col2])
df_train=df_train.compute()
print("load train: " , time.clock()-t)

Another working solution is:

import pandas as pd 
from tqdm import tqdm

PATH = '../data/train.csv'
chunksize = 500000 
traintypes = {
'col1':'category',
'col2':'str'}

cols = list(traintypes.keys())

df_list = [] # list to hold the batch dataframe

for df_chunk in tqdm(pd.read_csv(PATH, usecols=cols, dtype=traintypes, chunksize=chunksize)):
    # Can process each chunk of dataframe here
    # clean_data(), feature_engineer(),fit()

    # Alternatively, append the chunk to list and merge all
    df_list.append(df_chunk) 

# Merge all dataframes into one dataframe
X = pd.concat(df_list)

# Delete the dataframe list to release memory
del df_list
del df_chunk

In laymans terms, what does 'static' mean in Java?

In very laymen terms the class is a mold and the object is the copy made with that mold. Static belong to the mold and can be accessed directly without making any copies, hence the example above

How to restart a rails server on Heroku?

Just type the following commands from console.

cd /your_project
heroku restart

Replace the single quote (') character from a string

Here are a few ways of removing a single ' from a string in python.

  • str.replace

    replace is usually used to return a string with all the instances of the substring replaced.

    "A single ' char".replace("'","")
    
  • str.translate

    In Python 2

    To remove characters you can pass the first argument to the funstion with all the substrings to be removed as second.

    "A single ' char".translate(None,"'")
    

    In Python 3

    You will have to use str.maketrans

    "A single ' char".translate(str.maketrans({"'":None}))
    
  • re.sub

    Regular Expressions using re are even more powerful (but slow) and can be used to replace characters that match a particular regex rather than a substring.

    re.sub("'","","A single ' char")
    

Other Ways

There are a few other ways that can be used but are not at all recommended. (Just to learn new ways). Here we have the given string as a variable string.

Another final method can be used also (Again not recommended - works only if there is only one occurrence )

  • Using list call along with remove and join.

    x = list(string)
    x.remove("'")
    ''.join(x)
    

REST / SOAP endpoints for a WCF service

You can expose the service in two different endpoints. the SOAP one can use the binding that support SOAP e.g. basicHttpBinding, the RESTful one can use the webHttpBinding. I assume your REST service will be in JSON, in that case, you need to configure the two endpoints with the following behaviour configuration

<endpointBehaviors>
  <behavior name="jsonBehavior">
    <enableWebScript/>
  </behavior>
</endpointBehaviors>

An example of endpoint configuration in your scenario is

<services>
  <service name="TestService">
    <endpoint address="soap" binding="basicHttpBinding" contract="ITestService"/>
    <endpoint address="json" binding="webHttpBinding"  behaviorConfiguration="jsonBehavior" contract="ITestService"/>
  </service>
</services>

so, the service will be available at

Apply [WebGet] to the operation contract to make it RESTful. e.g.

public interface ITestService
{
   [OperationContract]
   [WebGet]
   string HelloWorld(string text)
}

Note, if the REST service is not in JSON, parameters of the operations can not contain complex type.

Reply to the post for SOAP and RESTful POX(XML)

For plain old XML as return format, this is an example that would work both for SOAP and XML.

[ServiceContract(Namespace = "http://test")]
public interface ITestService
{
    [OperationContract]
    [WebGet(UriTemplate = "accounts/{id}")]
    Account[] GetAccount(string id);
}

POX behavior for REST Plain Old XML

<behavior name="poxBehavior">
  <webHttp/>
</behavior>

Endpoints

<services>
  <service name="TestService">
    <endpoint address="soap" binding="basicHttpBinding" contract="ITestService"/>
    <endpoint address="xml" binding="webHttpBinding"  behaviorConfiguration="poxBehavior" contract="ITestService"/>
  </service>
</services>

Service will be available at

REST request try it in browser,

http://www.example.com/xml/accounts/A123

SOAP request client endpoint configuration for SOAP service after adding the service reference,

  <client>
    <endpoint address="http://www.example.com/soap" binding="basicHttpBinding"
      contract="ITestService" name="BasicHttpBinding_ITestService" />
  </client>

in C#

TestServiceClient client = new TestServiceClient();
client.GetAccount("A123");

Another way of doing it is to expose two different service contract and each one with specific configuration. This may generate some duplicates at code level, however at the end of the day, you want to make it working.

How to do SELECT MAX in Django?

Django also has the 'latest(field_name = None)' function that finds the latest (max. value) entry. It not only works with date fields but also with strings and integers.

You can give the field name when calling that function:

max_rated_entry = YourModel.objects.latest('rating')
return max_rated_entry.details

Or you can already give that field name in your models meta data:

from django.db import models

class YourModel(models.Model):
    #your class definition
    class Meta:
        get_latest_by = 'rating'

Now you can call 'latest()' without any parameters:

max_rated_entry = YourModel.objects.latest()
return max_rated_entry.details

OS X Framework Library not loaded: 'Image not found'

Got the issue when trying Xcode 9 beta and going back to Xcode 8. A simple Clean on the target resolved the issue.

I can't understand why this JAXB IllegalAnnotationException is thrown

I was having the same issue

My Issue

Caused by: java.security.PrivilegedActionException: com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 2 counts of IllegalAnnotationExceptions

Two classes have the same XML type name "{urn:cpq_tns_Kat_getgroupsearch}Kat_getgroupsearch". Use @XmlType.name and @XmlType.namespace to assign different names to them.
this problem is related to the following location:
at katrequest.cpq_tns_kat_getgroupsearch.KatGetgroupsearch
at public javax.xml.bind.JAXBElement katrequest.cpq_tns_kat_getgroupsearch.ObjectFactory.createKatGetgroupsearch(katrequest.cpq_tns_kat_getgroupsearch.KatGetgroupsearch)
at katrequest.cpq_tns_kat_getgroupsearch.ObjectFactory
this problem is related to the following location:
at cpq_tns_kat_getgroupsearch.KatGetgroupsearch

Two classes have the same XML type name "{urn:cpq_tns_Kat_getgroupsearch}Kat_getgroupsearchResponse0". Use @XmlType.name and @XmlType.namespace to assign different names to them.
this problem is related to the following location:
at katrequest.cpq_tns_kat_getgroupsearch.KatGetgroupsearchResponse0
at public javax.xml.bind.JAXBElement katrequest.cpq_tns_kat_getgroupsearch.ObjectFactory.createKatGetgroupsearchResponse0(katrequest.cpq_tns_kat_getgroupsearch.KatGetgroupsearchResponse0)
at katrequest.cpq_tns_kat_getgroupsearch.ObjectFactory
this problem is related to the following location:
at cpq_tns_kat_getgroupsearch.KatGetgroupsearchResponse0

Changed made to solve it are below

I change the respective name to namespace

@XmlAccessorType(XmlAccessType.FIELD) @XmlType(**name** =
    "Kat_getgroupsearch", propOrder = {

    @XmlAccessorType(XmlAccessType.FIELD) @XmlType(namespace =
    "Kat_getgroupsearch", propOrder = {


@XmlAccessorType(XmlAccessType.FIELD)
@XmlType(**name** = "Kat_getgroupsearchResponse0", propOrder = {

   @XmlAccessorType(XmlAccessType.FIELD)
   @XmlType(namespace = "Kat_getgroupsearchResponse0", propOrder = {

why?

As written in error log two classes have same name so we should use namespace because XML namespaces are used for providing uniquely named elements and attributes in an XML document.

Delete all SYSTEM V shared memory and semaphores on UNIX-like systems

I don't know how to delete all at once, but you can use ipcs to list resources, and then use loop and delete with ipcrm. This should work, but it needs a little work. I remember that I made it work once in class.

basic authorization command for curl

Use the -H header again before the Authorization:Basic things. So it will be

curl -i \
    -H 'Accept:application/json' \
    -H 'Authorization:Basic BASE64_string' \
    http://example.com

Here, BASE64_string = Base64 of username:password

Git status shows files as changed even though contents are the same

For me it was because 2 linux VMs were both mapped to the same home file system. One VM was running git-1.7.1 an the other was running git-2.14

The VM running git-1.7.1 would always show 4 files as changed (even thought the contents and line endings were identical).

Once 'git status' was run on the VM running g-2.14, then both VMs would start reporting the repository as clean. 'git status' has side effects. It is not an immutable operation. And git-1.7.1 does not understand the world in the same way that git-2+ does.

Selecting only first-level elements in jquery

You might want to try this if results still flows down to children, in many cases JQuery will still apply to children.

$("ul.rootlist > li > a")

Using this method: E > F Matches any F element that is a child of an element E.

Tells JQuery to look only for explicit children. http://www.w3.org/TR/CSS2/selector.html

How to use cURL in Java?

You can make use of java.net.URL and/or java.net.URLConnection.

URL url = new URL("https://stackoverflow.com");

try (BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream(), "UTF-8"))) {
    for (String line; (line = reader.readLine()) != null;) {
        System.out.println(line);
    }
}

Also see the Oracle's simple tutorial on the subject. It's however a bit verbose. To end up with less verbose code, you may want to consider Apache HttpClient instead.

By the way: if your next question is "How to process HTML result?", then the answer is "Use a HTML parser. No, don't use regex for this.".

See also:

Toggle Class in React

You have to use the component's State to update component parameters such as Class Name if you want React to render your DOM correctly and efficiently.

UPDATE: I updated the example to toggle the Sidemenu on a button click. This is not necessary, but you can see how it would work. You might need to use "this.state" vs. "this.props" as I have shown. I'm used to working with Redux components.

constructor(props){
    super(props);
}

getInitialState(){
  return {"showHideSidenav":"hidden"};
}

render() {
    return (
        <div className="header">
            <i className="border hide-on-small-and-down"></i>
            <div className="container">
                <a ref="btn" onClick={this.toggleSidenav.bind(this)} href="#" className="btn-menu show-on-small"><i></i></a>
                <Menu className="menu hide-on-small-and-down"/>
                <Sidenav className={this.props.showHideSidenav}/>
            </div>
        </div>
    )
}

toggleSidenav() {
    var css = (this.props.showHideSidenav === "hidden") ? "show" : "hidden";
    this.setState({"showHideSidenav":css});
}

Now, when you toggle the state, the component will update and change the class name of the sidenav component. You can use CSS to show/hide the sidenav using the class names.

.hidden {
   display:none;
}
.show{
   display:block;
}

Downloading Java JDK on Linux via wget is shown license page instead

Instead of using for every new Java version a new link or changing existing scripts, I was looking for a more generic way to automate the download of the required Java packages and later installation via yum localinstall ${JAVA_ENVIRONMENT}-${JAVA_VERSION}-linux-x64.rpm.

I've used a somehow trivial approach similar to manual/user action to find the package and to download it. I am also pretty sure that one will find a more elegant way to do it by using other tools like egrep, awk, etc.., so leave it as an example here:

#!/bin/bash

### Proxy settings
# If there is a company proxy 

PROXY="my.proxy.local:8080"
PROXY_TYPE="--proxy-ntlm" # or leave empty with ""
USER="user"
PASS='pass'

### Find out the links to JRE and JDK 
# To do so, got to the page http://www.oracle.com/technetwork/java/javase/downloads/

BASE_URL="technetwork/java/javase/downloads"

# Put the whole page into a single string/line

BASE_URL_OUTPUT="$(curl -s -k ${PROXY_TYPE} -x "http://${USER}:${PASS}@${PROXY}" -L0 http://www.oracle.com/${BASE_URL}/)"

# Define the environments to download 

JAVA_ENVIRONMENTS=("JRE" "JDK") # ! yet "SERVER-JRE"

for JAVA_ENVIRONMENT in "${JAVA_ENVIRONMENTS[@]}"
do

echo
echo "JAVA_ENVIRONMENT="$JAVA_ENVIRONMENT
echo

for (( JAVA_BASE_VERSION = 8; JAVA_BASE_VERSION <= 10; JAVA_BASE_VERSION += 2 ))  
do

echo "JAVA_BASE_VERSION="$JAVA_BASE_VERSION

### "Read the page"
# and follow the links for the package interested in 

DOWNLOAD_SITE="$(echo $BASE_URL_OUTPUT | grep -m 1 -io "${JAVA_ENVIRONMENT}${JAVA_BASE_VERSION}-downloads-[0-9]*.html" -- | tail -1)"
echo "DOWNLOAD_SITE="$DOWNLOAD_SITE

### Gather the necessary download links
# To do so, following the link to the download site
# reading and accept the license 
# 
# ... the greedy regular expression is to address the different syntax of the links
# and already prepared for OR .gz files 

DOWNLOAD_LINK_OUTPUT="$(curl -s -k ${PROXY_TYPE} -x "http://${USER}:${PASS}@${PROXY}" -L -j -H "Cookie: oraclelicense=accept-securebackup-cookie" http://www.oracle.com/${BASE_URL}/${DOWNLOAD_SITE} |  grep -io "filepath.*${JAVA_ENVIRONMENT}-[${JAVA_BASE_VERSION}].*linux[-_]x64[._].*\(rpm\)" -- | cut -d '"' -f 3 | tail -1)"

# and echo out the link

echo "DOWNLOAD_LINK_OUTPUT="$DOWNLOAD_LINK_OUTPUT

done

done

Since the download links are available now, one may proceed further with wget or curl.

LINQ query to return a Dictionary<string, string>

Use the ToDictionary method directly.

var result = 
  // as Jon Skeet pointed out, OrderBy is useless here, I just leave it 
  // show how to use OrderBy in a LINQ query
  myClassCollection.OrderBy(mc => mc.SomePropToSortOn)
                   .ToDictionary(mc => mc.KeyProp.ToString(), 
                                 mc => mc.ValueProp.ToString(), 
                                 StringComparer.OrdinalIgnoreCase);

How do I find an element that contains specific text in Selenium WebDriver (Python)?

You can also use it with Page Object Pattern, e.g:

Try this code:

@FindBy(xpath = "//*[contains(text(), 'Best Choice')]")
WebElement buttonBestChoice;

Checking if a variable is initialized

There's no reasonable way to check whether a value has been initialized.

If you care about whether something has been initialized, instead of trying to check for it, put code into the constructor(s) to ensure that they are always initialized and be done with it.

What difference is there between WebClient and HTTPWebRequest classes in .NET?

WebClient is a higher-level abstraction built on top of HttpWebRequest to simplify the most common tasks. For instance, if you want to get the content out of an HttpWebResponse, you have to read from the response stream:

var http = (HttpWebRequest)WebRequest.Create("http://example.com");
var response = http.GetResponse();

var stream = response.GetResponseStream();
var sr = new StreamReader(stream);
var content = sr.ReadToEnd();

With WebClient, you just do DownloadString:

var client = new WebClient();
var content = client.DownloadString("http://example.com");

Note: I left out the using statements from both examples for brevity. You should definitely take care to dispose your web request objects properly.

In general, WebClient is good for quick and dirty simple requests and HttpWebRequest is good for when you need more control over the entire request.

Remove Elements from a HashSet while Iterating

you can also refactor your solution removing the first loop:

Set<Integer> set = new HashSet<Integer>();
Collection<Integer> removeCandidates = new LinkedList<Integer>(set);

for(Integer element : set)
   if(element % 2 == 0)
       removeCandidates.add(element);

set.removeAll(removeCandidates);

Dockerfile if else condition with external arguments

The accepted answer may solve the question, but if you want multiline if conditions in the dockerfile, you can do that placing \ at the end of each line (similar to how you would do in a shell script) and ending each command with ;. You can even define someting like set -eux as the 1st command.

Example:

RUN set -eux; \
  if [ -f /path/to/file ]; then \
    mv /path/to/file /dest; \
  fi; \
  if [ -d /path/to/dir ]; then \
    mv /path/to/dir /dest; \
  fi

In your case:

FROM centos:7
ARG arg
RUN if [ -z "$arg" ] ; then \
    echo Argument not provided; \
  else \
    echo Argument is $arg; \
  fi

Then build with:

docker build -t my_docker . --build-arg arg=42

How to easily map c++ enums to strings

typedef enum {
    ERR_CODE_OK = 0,
    ERR_CODE_SNAP,

    ERR_CODE_NUM
} ERR_CODE;

const char* g_err_msg[ERR_CODE_NUM] = {
    /* ERR_CODE_OK   */ "OK",
    /* ERR_CODE_SNAP */ "Oh, snap!",
};

Above is my simple solution. One benefit of it is the 'NUM' which controls the size of the message array, it also prevents out of boundary access (if you use it wisely).

You can also define a function to get the string:

const char* get_err_msg(ERR_CODE code) {
    return g_err_msg[code];
}

Further to my solution, I then found the following one quite interesting. It generally solved the sync problem of the above one.

Slides here: http://www.slideshare.net/arunksaha/touchless-enum-tostring-28684724

Code here: https://github.com/arunksaha/enum_to_string

The first day of the current month in php using date_modify as DateTime object

Currently I'm using this solution:

$firstDay = new \DateTime('first day of this month');
$lastDay = new \DateTime('last day of this month');

The only issue I came upon is that strange time is being set. I needed correct range for our search interface and I ended up with this:

$firstDay = new \DateTime('first day of this month 00:00:00');
$lastDay = new \DateTime('first day of next month 00:00:00');

Button Listener for button in fragment in android

Simply pass view object into onButtonClicked function. getView() does not seem to work as expected inside fragment. Try this code for your FragmentOne fragment

PS. you have redefined object view in your original FragmentOne code.

package com.example.fragmenttutorial;

import android.app.Fragment;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class FragmentOne extends Fragment{

    FragmentManager fragmentManager = getFragmentManager();
    FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View view = inflater.inflate(R.layout.fragment_one, container, false);
        onButtonClicked(view);
        return view;
    }

  protected void onButtonClicked(View view)
  {
      if(view.getId() == R.id.buttonSayHi){
          Fragment fragmentTwo = new FragmentTwo();

          fragmentTransaction.replace(R.id.frameLayoutFragmentContainer, fragmentTwo);
          fragmentTransaction.addToBackStack(null);

          fragmentTransaction.commit();   

     }

How do I include the string header?

I don't hear about "apstring".If you want to use string with c++ ,you can do like this:

#include<string>
using namespace std;
int main()
{
   string str;
   cin>>str;
   cout<<str;
   ...
   return 0;
}

I hope this can avail

Posting parameters to a url using the POST method without using a form

cURL is an option, using Ajax as well eventhough solving back-end problems with the front-end isn't so neat.

A very useful post about doing it without cURL is this one: http://netevil.org/blog/2006/nov/http-post-from-php-without-curl

The code to do this (untested, unimproved, from the blog post):

function do_post_request($url, $data, $optional_headers = null)
{
   $params = array('http' => array(
                'method' => 'POST',
                'content' => $data
             ));
   if ($optional_headers !== null) {
      $params['http']['header'] = $optional_headers;
   }
   $ctx = stream_context_create($params);
   $fp = @fopen($url, 'rb', false, $ctx);
   if (!$fp) {
      throw new Exception("Problem with $url, $php_errormsg");
   }
   $response = @stream_get_contents($fp);
   if ($response === false) {
      throw new Exception("Problem reading data from $url, $php_errormsg");
   }
   return $response;
}

The system cannot find the file specified. in Visual Studio

Another take on this that hasn't been mentioned here is that, when in debug, the project may build, but it won't run, giving the error message displayed in the question.

If this is the case, another option to look at is the output file versus the target file. These should match.

A quick way to check the output file is to go to the project's property pages, then go to Configuration Properties -> Linker -> General (In VS 2013 - exact path may vary depending on IDE version).

There is an "Output File" setting. If it is not $(OutDir)$(TargetName)$(TargetExt), then you may run into issues.

This is also discussed in more detail here.

How to check if a string is a valid JSON string in JavaScript without using Try/Catch

I know i'm 3 years late to this question, but I felt like chiming in.

While Gumbo's solution works great, it doesn't handle a few cases where no exception is raised for JSON.parse({something that isn't JSON})

I also prefer to return the parsed JSON at the same time, so the calling code doesn't have to call JSON.parse(jsonString) a second time.

This seems to work well for my needs:

function tryParseJSON (jsonString){
    try {
        var o = JSON.parse(jsonString);

        // Handle non-exception-throwing cases:
        // Neither JSON.parse(false) or JSON.parse(1234) throw errors, hence the type-checking,
        // but... JSON.parse(null) returns null, and typeof null === "object", 
        // so we must check for that, too. Thankfully, null is falsey, so this suffices:
        if (o && typeof o === "object") {
            return o;
        }
    }
    catch (e) { }

    return false;
};

When should I use git pull --rebase?

Perhaps the best way to explain it is with an example:

  1. Alice creates topic branch A, and works on it
  2. Bob creates unrelated topic branch B, and works on it
  3. Alice does git checkout master && git pull. Master is already up to date.
  4. Bob does git checkout master && git pull. Master is already up to date.
  5. Alice does git merge topic-branch-A
  6. Bob does git merge topic-branch-B
  7. Bob does git push origin master before Alice
  8. Alice does git push origin master, which is rejected because it's not a fast-forward merge.
  9. Alice looks at origin/master's log, and sees that the commit is unrelated to hers.
  10. Alice does git pull --rebase origin master
  11. Alice's merge commit is unwound, Bob's commit is pulled, and Alice's commit is applied after Bob's commit.
  12. Alice does git push origin master, and everyone is happy they don't have to read a useless merge commit when they look at the logs in the future.

Note that the specific branch being merged into is irrelevant to the example. Master in this example could just as easily be a release branch or dev branch. The key point is that Alice & Bob are simultaneously merging their local branches to a shared remote branch.

Get the length of a String

As of Swift 4+

It's just:

test1.count

for reasons.

(Thanks to Martin R)

As of Swift 2:

With Swift 2, Apple has changed global functions to protocol extensions, extensions that match any type conforming to a protocol. Thus the new syntax is:

test1.characters.count

(Thanks to JohnDifool for the heads up)

As of Swift 1

Use the count characters method:

let unusualMenagerie = "Koala &#128040;, Snail &#128012;, Penguin &#128039;, Dromedary &#128042;"
println("unusualMenagerie has \(count(unusualMenagerie)) characters")
// prints "unusualMenagerie has 40 characters"

right from the Apple Swift Guide

(note, for versions of Swift earlier than 1.2, this would be countElements(unusualMenagerie) instead)

for your variable, it would be

length = count(test1) // was countElements in earlier versions of Swift

Or you can use test1.utf16count

XAMPP MySQL password setting (Can not enter in PHPMYADMIN)

First Issue: You want to run Mysql server from Mysql and from Xampp also want to browse phpmyadmin so that you can operate database.Then follow the rules:

From "Xampp/phpmyadmin" directory in config.inc.php file find the below code. And follow the given instructions below. I have tried like this and I was successful to run both localhost/phpMyAdmin on browser, MySQL Command prompt as well as MySQL query browser.

$cfg['Servers'][$i]['auth_type']    = 'config';
$cfg['Servers'][$i]['user']         = 'pma';
$cfg['Servers'][$i]['password']     = '';
$cfg['Servers'][$i]['controluser']  = 'user_name/root';   
$cfg['Servers'][$i]['controlpass']  = 'passwaord';

And replace the above each statement with the below each corresponding code.

$cfg['Servers'][$i]['auth_type']    = 'config';
$cfg['Servers'][$i]['user']         = 'root';
$cfg['Servers'][$i]['password']     = 'Muhammad Ashikuzzaman';
$cfg['Servers'][$i]['controluser']  = 'root';   
$cfg['Servers'][$i]['controlpass']  = 'Muhammad Ashikuzzaman';

Second Issue: Way 1 : You can quit Skype first. And when Apche server is started then again you can run Skype. If you want to run Apache in another port then replace in xampp/apache/conf/httpd.conf "ServerName localhost:80" by "ServerName localhost:81" At line 184. After that even it may not work. Then replace

#Listen 0.0.0.0:80
#Listen [::]:80
Listen 80 

by

#Listen 0.0.0.0:81
#Listen [::]:81
Listen 81

at line 45

Way 2 : If you want to use port 80. Then follow this. In Windows 8 “World Wide Publishing Service is using this port and stopping this service will free the port 80 and you can connect Apache using this port. To stop the service go to the “Task manager –> Services tab”, right click the “World Wide Publishing Service” and stop. If you don't find there then go to "Run > services.msc" and again find there and right click the “World Wide Publishing Service” and stop.

If you didn't find “World Wide Publishing Service” there then go to "Run>>resmon.exe>> Network Tab>>Listening Ports" and see which process is using port 80.

And from "Overview>>CPU" just Right click on that process and click "End Process Tree". If that process is system that might be a critical issue.

default web page width - 1024px or 980px?

If it isn't I could see things heading that way.

I'm working on redoing the website for the company I work for and the designer they hired used a 960px width layout. There is also a 960px grid system that seems to be getting quite popular (http://960.gs/).

I've been out of web stuff for a few years but from what I've read catching up on things it seems 960/980 is about right. For mobile ~320px sticks in my mind, by which 960 is divisible. 960 is also evenly divisible by 2, 3, 4, 5, and 6.

Adding a line break in MySQL INSERT INTO text

If you're OK with a SQL command that spreads across multiple lines, then oedo's suggestion is the easiest:

INSERT INTO mytable (myfield) VALUES ('hi this is some text
and this is a linefeed.
and another');

I just had a situation where it was preferable to have the SQL statement all on one line, so I found that a combination of CONCAT_WS() and CHAR() worked for me.

INSERT INTO mytable (myfield) VALUES (CONCAT_WS(CHAR(10 using utf8), 'hi this is some text', 'and this is a linefeed.', 'and another'));

PHP error: "The zip extension and unzip command are both missing, skipping."

For older Ubuntu distros i.e 16.04, 14.04, 12.04 etc

sudo apt-get install zip unzip php7.0-zip

C# Ignore certificate errors?

Allowing all certificates is very powerful but it could also be dangerous. If you would like to only allow valid certificates plus some certain certificates it could be done like this.

.Net core:

using (var httpClientHandler = new HttpClientHandler())
{
    httpClientHandler.ServerCertificateCustomValidationCallback = (message, cert, chain, sslPolicyErrors) => {
        if (sslPolicyErrors == SslPolicyErrors.None)
        {
            return true;   //Is valid
        }

        if (cert.GetCertHashString() == "99E92D8447AEF30483B1D7527812C9B7B3A915A7")
        {
            return true;
        }
        return false;
    };
    using (var httpClient = new HttpClient(httpClientHandler))
    {
        var httpResponse = httpClient.GetAsync("https://example.com").Result;
    }
}

.Net framework:

System.Net.ServicePointManager.ServerCertificateValidationCallback += delegate (
    object sender,
    X509Certificate cert,
    X509Chain chain,
    SslPolicyErrors sslPolicyErrors)
{
    if (sslPolicyErrors == SslPolicyErrors.None)
    {
        return true;   //Is valid
    }

    if (cert.GetCertHashString() == "99E92D8447AEF30483B1D7527812C9B7B3A915A7")
    {
        return true;
    }

    return false;
};

Update:

How to get cert.GetCertHashString() value in Chrome:

Click on Secure or Not Secure in the address bar.

enter image description here

enter image description here

Then click on Certificate -> Details -> Thumbprint and copy the value. Remember to do cert.GetCertHashString().ToLower().

enter image description here

Run a script in Dockerfile

WORKDIR /scripts
COPY bootstrap.sh .
RUN ./bootstrap.sh 

How can I get a list of users from active directory?

Certainly the credit goes to @Harvey Kwok here, but I just wanted to add this example because in my case I wanted to get an actual List of UserPrincipals. It's probably more efficient to filter this query upfront, but in my small environment, it's just easier to pull everything and then filter as needed later from my list.

Depending on what you need, you may not need to cast to DirectoryEntry, but some properties are not available from UserPrincipal.

using (var searcher = new PrincipalSearcher(new UserPrincipal(new PrincipalContext(ContextType.Domain, Environment.UserDomainName))))
{
    List<UserPrincipal> users = searcher.FindAll().Select(u => (UserPrincipal)u).ToList();
    foreach(var u in users)
        {
            DirectoryEntry d = (DirectoryEntry)u.GetUnderlyingObject();
            Console.WriteLine(d.Properties["GivenName"]?.Value?.ToString() + d.Properties["sn"]?.Value?.ToString());
        }
}

AngularJS - pass function to directive

In your 'test' directive Html tag, the attribute name of the function should not be camelCased, but dash-based.

so - instead of :

<test color1="color1" updateFn="updateFn()"></test>

write:

<test color1="color1" update-fn="updateFn()"></test>

This is angular's way to tell the difference between directive attributes (such as update-fn function) and functions.

Putting a simple if-then-else statement on one line

count = 0 if count == N else N+1

- the ternary operator. Although I'd say your solution is more readable than this.

Add Custom Headers using HttpWebRequest

You should do ex.StackTrace instead of ex.ToString()

Apply style ONLY on IE

Here is a COMPLETE Javascript-free, CSS-based solution that allows you to target Internet Explorer 1-11!

My Internet Explorer Only CSS Solution

This works by hiding IE1-7 from all your modern sheets using @import, giving IE1-7 a clean, white page layout, then applies three simple CSS media query "hacks" to isolate IE8-11 in the imported sheet. It even affects IE on Mac!

The advantage to this strategy is its 100% effective in targeting IE1-11, giving you complete control over how you customize CSS for those targeted browsers, while freeing you up as a designer to focus on newer CSS3 and cutting-edge styles and layouts in Edge and all other modern browsers going forward. I have been using a version of this since 2004 but recently updated it for 2021.

HOW IT WORKS

First create two CSS style sheet links. The first is a basic element style sheet that gives all browsers, old and new, a simple white, block-level layout. Linked CSS has wide support in older CSS1 browsers going back to 1995. A wide range of old browsers will see this first sheet and display your content and layouts in a clean, white block-level content page. I like to put "reset" element-only styles in here. The second sheet is an import sheet that will load all your advanced CSS styles using a single @import rule that hides styles to a wide range of browsers including IE1-7.

<link media="screen" rel="stylesheet" type="text/css" href="OldBrowsers.css" />
<link media="screen" rel="stylesheet" type="text/css" href="Import.css" />

Next, in your "Import.css" sheet add this @import rule exactly as formatted (Its hidden from IE1-7 and a wide range of older browsers listed below):

@import 'ModernBrowsers.css' all;

All CSS in this imported sheet will be hidden from IE1-7 and a wide range of older browsers. IE 1-7 doesn't understand "media type" value "all" so will fail to import this sheet. This specific version of import is also not recognized by many older browsers (pre-2001). Those browsers are so old now, you just need to deliver them a white web page with stacked blocks of content. Use "OldBrowsers" to do so.

Next, in "ModernBrowsers.css" you want to target IE8-11 using CSS media query "hacks" alongside all your normal selectors and classes. Simply apply the following media query, IE-only fixes to your modern, imported style sheet to target these specific IE browsers. Drop into these blocks any styles specific to them. You can attack your layout or other style issues in IE now in media query "batches" now rather than by multiple selector "hacks":

/* IE8 */
@media \0screen {
    body {
        background: red !important;
    }
}

/* IE9 */
@media all and (monochrome:0) {
    body {
        background: blue\9 !important;
    }
}

/* IE10-11 */
@media all and (-ms-high-contrast: none), (-ms-high-contrast: active) {
    body {
        background: green !important;
    }
}

Simple! You have now targeted styles for IE1-11 (all Internet Explorer browsers!)

With this solution you achieve the following:

  1. The @import excludes IE 1-7 from your modern styles, completely! Those agents, along with the list below, will never see your modern imported styles and get a clean white style sheet content page older browsers can still use as far as viewing your content (use "OldBrowsers.css" to style them). The following browsers are excluded from "ModernBrowsers.css" using the above @import rule:

    • Windows Internet Explorer 1-7.x
    • Macintosh Internet Explorer 1-5.x
    • Netscape 1-4.8
    • Opera 1-3.5
    • Konqueror 1-2.1
    • Windows Amaya 1-5.1
    • iCab 1-2
    • OmniWeb
  2. In your "ModernBrowsers" imported sheet, you can now safely target IE browsers version 8-11 using simple media query "hacks".

  3. This system uses a simple @import style sheet system that is fast and manageable using traditional, non-support for external style rules rather than CSS fixes sprinkled throughout multiple sheets. (BTW...Do not listen to anyone saying @import is slow, as it is not. My import sheet has ONE LINE and is maybe a kilobyte or less in size! @import has been used since the birth of the WWW and is no different than a simple CSS link. Compare this to the Megabytes of Javascript kids today are shoving into browsers using these new "modern" ECMAScript SPA API's just to display a tiny paragraph of news!)

  4. All old IE browsers and a wide range of other user agnets are excluded from modern styles now using this import strategy, which allows these agents to collapse back to plain, "block-level", white pages and stacked content layouts that are fully accessible by older browsers.

  5. Notice this solution has no IE conditional comments! (you should NEVER use those)

  6. With this solution, web designs are now 100% free to use custom, cutting edge CSS3 technologies without having to ever worry about older browsers and IE1-11 ever again!

I will be posting my formal version of this Universal CSS System on GitHub soon! So stay tuned...

This is part of the new "progressive" CSS, 100% Javacript-free, design concept in 2021 for addressing cross-browser style issues, where older agents are allowed to degrade gracefully to simpler layouts rather than struggling to fix problems in cryptic old, broken, box-model agents (IE6) that don't need custom layouts any longer today as the long tail of their slow demise continues online.

And its my hope we stop creating these gigantic, CPU-hog, Javascripted, polyfill nightmare solutions for addressing what used to be years ago solved by simple CSS solutions like this one.

Count how many files in directory PHP

You can get the filecount like so:

$directory = "/path/to/dir/";
$filecount = 0;
$files = glob($directory . "*");
if ($files){
 $filecount = count($files);
}
echo "There were $filecount files";

where the "*" is you can change that to a specific filetype if you want like "*.jpg" or you could do multiple filetypes like this:

glob($directory . "*.{jpg,png,gif}",GLOB_BRACE)

the GLOB_BRACE flag expands {a,b,c} to match 'a', 'b', or 'c'

"message failed to fetch from registry" while trying to install any module

One thing that has worked for me with random npm install errors (where the package that errors out is different under different times (but same environment) is to use this:

npm cache clean

And then repeat the process. Then the process seems to go smoother and the real problem and error message will emerge, where you can fix it and then proceed.

This is based on experience of running npm install of a whole bunch of packages under a pretty bare Ubuntu installation inside a Docker instance. Sometimes there are build/make tools missing from the Ubuntu and the npm errors will not show the real problem until you clean the cache for some reason.

How do I convert this list of dictionaries to a csv file?

import csv
toCSV = [{'name':'bob','age':25,'weight':200},
         {'name':'jim','age':31,'weight':180}]
keys = toCSV[0].keys()
with open('people.csv', 'w', newline='')  as output_file:
    dict_writer = csv.DictWriter(output_file, keys)
    dict_writer.writeheader()
    dict_writer.writerows(toCSV)

EDIT: My prior solution doesn't handle the order. As noted by Wilduck, DictWriter is more appropriate here.

ExecuteNonQuery doesn't return results

You use EXECUTENONQUERY() for INSERT,UPDATE and DELETE.

But for SELECT you must use EXECUTEREADER().........

Removing numbers from string

I'd love to use regex to accomplish this, but since you can only use lists, loops, functions, etc..

here's what I came up with:

stringWithNumbers="I have 10 bananas for my 5 monkeys!"
stringWithoutNumbers=''.join(c if c not in map(str,range(0,10)) else "" for c in stringWithNumbers)
print(stringWithoutNumbers) #I have  bananas for my  monkeys!

Objective C - Assign, Copy, Retain

  1. assign

    • assign is a default property attribute
    • assign is a property attribute tells the compiler how to synthesize the property’s setter implementation
  2. copy:

    • copy is required when the object is mutable
    • copy returns an object which you must explicitly release (e.g., in dealloc) in non-garbage collected environments
    • you need to release the object when finished with it because you are retaining the copy
  3. retain:

    • specifies the new value should be sent “-retain” on assignment and the old value sent “-release”
    • if you write retain it will auto work like strong
    • Methods like “alloc” include an implicit “retain”

How does Subquery in select statement work in oracle

It's simple-

SELECT empname,
       empid,
       (SELECT COUNT (profileid)
          FROM profile
         WHERE profile.empid = employee.empid)
           AS number_of_profiles
  FROM employee;

It is even simpler when you use a table join like this:

  SELECT e.empname, e.empid, COUNT (p.profileid) AS number_of_profiles
    FROM employee e LEFT JOIN profile p ON e.empid = p.empid
GROUP BY e.empname, e.empid;

Explanation for the subquery:

Essentially, a subquery in a select gets a scalar value and passes it to the main query. A subquery in select is not allowed to pass more than one row and more than one column, which is a restriction. Here, we are passing a count to the main query, which, as we know, would always be only a number- a scalar value. If a value is not found, the subquery returns null to the main query. Moreover, a subquery can access columns from the from clause of the main query, as shown in my query where employee.empid is passed from the outer query to the inner query.


Edit:

When you use a subquery in a select clause, Oracle essentially treats it as a left join (you can see this in the explain plan for your query), with the cardinality of the rows being just one on the right for every row in the left.


Explanation for the left join

A left join is very handy, especially when you want to replace the select subquery due to its restrictions. There are no restrictions here on the number of rows of the tables in either side of the LEFT JOIN keyword.

For more information read Oracle Docs on subqueries and left join or left outer join.

Hibernate Group by Criteria Object

If you have to do group by using hibernate criteria use projections.groupPropery like the following,

@Autowired
private SessionFactory sessionFactory;
Criteria crit = sessionFactory.getCurrentSession().createCriteria(studentModel.class);
crit.setProjection(Projections.projectionList()
            .add(Projections.groupProperty("studentName").as("name"))
List result = crit.setResultTransformer(Criteria.ALIAS_TO_ENTITY_MAP).list(); 
return result;  

Java stack overflow error - how to increase the stack size in Eclipse?

When using JBOSS Server, double click on the server:

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Go to "Open Launch Configuration"

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Then change min and max memory sizes (like 1G, 1m):

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How to filter rows in pandas by regex

Write a Boolean function that checks the regex and use apply on the column

foo[foo['b'].apply(regex_function)]

Maximum execution time in phpMyadmin

Go to xampp/php/php.ini

Find this line:

max_execution_time=30

And change its value to any number you want. Restart Apache.