Programs & Examples On #Jotm

JOTM is an open source JTA transaction manager.

How to convert flat raw disk image to vmdk for virtualbox or vmplayer?

First, install QEMU. On Debian-based distributions like Ubuntu, run:

$ apt-get install qemu

Then run the following command:

$ qemu-img convert -O vmdk imagefile.dd vmdkname.vmdk

I’m assuming a flat disk image is a dd-style image. The convert operation also handles numerous other formats.

For more information about the qemu-img command, see the output of

$ qemu-img -h

Hashing a dictionary?

While hash(frozenset(x.items()) and hash(tuple(sorted(x.items())) work, that's doing a lot of work allocating and copying all the key-value pairs. A hash function really should avoid a lot of memory allocation.

A little bit of math can help here. The problem with most hash functions is that they assume that order matters. To hash an unordered structure, you need a commutative operation. Multiplication doesn't work well as any element hashing to 0 means the whole product is 0. Bitwise & and | tend towards all 0's or 1's. There are two good candidates: addition and xor.

from functools import reduce
from operator import xor

class hashable(dict):
    def __hash__(self):
        return reduce(xor, map(hash, self.items()), 0)

    # Alternative
    def __hash__(self):
        return sum(map(hash, self.items()))

One point: xor works, in part, because dict guarantees keys are unique. And sum works because Python will bitwise truncate the results.

If you want to hash a multiset, sum is preferable. With xor, {a} would hash to the same value as {a, a, a} because x ^ x ^ x = x.

If you really need the guarantees that SHA makes, this won't work for you. But to use a dictionary in a set, this will work fine; Python containers are resiliant to some collisions, and the underlying hash functions are pretty good.

How do we change the URL of a working GitLab install?

GitLab Omnibus

For an Omnibus install, it is a little different.

The correct place in an Omnibus install is:

/etc/gitlab/gitlab.rb
    external_url 'http://gitlab.example.com'

Finally, you'll need to execute sudo gitlab-ctl reconfigure and sudo gitlab-ctl restart so the changes apply.


I was making changes in the wrong places and they were getting blown away.

The incorrect paths are:

/opt/gitlab/embedded/service/gitlab-rails/config/gitlab.yml
/var/opt/gitlab/.gitconfig
/var/opt/gitlab/nginx/conf/gitlab-http.conf

Pay attention to those warnings that read:

# This file is managed by gitlab-ctl. Manual changes will be
# erased! To change the contents below, edit /etc/gitlab/gitlab.rb
# and run `sudo gitlab-ctl reconfigure`.

Scroll to the top of the page after render in react.js

If I assume you are rendering a chapter of say, a book per page, all you need to do is add this to your code. This worked for me like magic.

    componentDidUpdate(prevProps) {
      if (prevProps.currentChapter !== this.props.currentChapter) {
        window.scrollTo(0, 0);
      }
    }

With this, you have no need creating a ref on the component being rendered.

Using Custom Domains With IIS Express

David's solution is good. But I found the <script>alert(document.domain);</script> in the page still alerts "localhost" because the Project Url is still localhost even if it has been override with http://dev.example.com. Another issue I run into is that it alerts me the port 80 has already been in use even if I have disabled the Skype using the 80 port number as recommended by David Murdoch. So I have figured out another solution that is much easier:

  1. Run Notepad as administrator, and open the C:\Windows\System32\drivers\etc\hosts, add 127.0.0.1 mydomain, and save the file;
  2. Open the web project with Visual Studio 2013 (Note: must also run as administrator), right-click the project -> Properties -> Web, (lets suppose the Project Url under the "IIS Express" option is http://localhost:33333/), then change it from http://localhost:33333/ to http://mydomain:333333/ Note: After this change, you should neither click the "Create Virtual Directory" button on the right of the Project Url box nor click the Save button of the Visual Studio as they won't be succeeded. You can save your settings after next step 3.
  3. Open %USERPROFILE%\My Documents\IISExpress\config\applicationhost.config, search for "33333:localhost", then update it to "33333:mydomain" and save the file.
  4. Save your setting as mentioned in step 2.
  5. Right click a web page in your visual studio, and click "View in Browser". Now the page will be opened under http://mydomain:333333/, and <script>alert(document.domain);</script> in the page will alert "mydomain".

Note: The port number listed above is assumed to be 33333. You need to change it to the port number set by your visual studio.

Post edited: Today I tried with another domain name and got the following error: Unable to launch the IIS Express Web server. Failed to register URL... Access is denied. (0x80070005). I exit the IIS Express by right clicking the IIS Express icon at the right corner in the Windows task bar, and then re-start my visual studio as administrator, and the issue is gone.

format a Date column in a Data Frame

This should do it (where df is your dataframe)

df$JoiningDate <- as.Date(df$JoiningDate , format = "%m/%d/%y")

df[order(df$JoiningDate ),]

How to show the text on a ImageButton?

you can use a regular Button and the android:drawableTop attribute (or left, right, bottom) instead.

File Explorer in Android Studio

Android 3.4.1 > Top Menu > View > Tools Window > Device File Manager

Getting a union of two arrays in JavaScript

ES2015 version

Array.prototype.diff = function(a) {return this.filter(i => a.indexOf(i) < 0)};

Array.prototype.union = function(a) {return [...this.diff(a), ...a]}

MySQL Select Date Equal to Today

You can use the CONCAT with CURDATE() to the entire time of the day and then filter by using the BETWEEN in WHERE condition:

SELECT users.id, DATE_FORMAT(users.signup_date, '%Y-%m-%d') 
FROM users 
WHERE (users.signup_date BETWEEN CONCAT(CURDATE(), ' 00:00:00') AND CONCAT(CURDATE(), ' 23:59:59'))

In Python try until no error

Maybe something like this:

connected = False

while not connected:
    try:
        try_connect()
        connected = True
    except ...:
        pass

Executing set of SQL queries using batch file?

Save the commands in a .SQL file, ex: ClearTables.sql, say in your C:\temp folder.

Contents of C:\Temp\ClearTables.sql

Delete from TableA;
Delete from TableB;
Delete from TableC;
Delete from TableD;
Delete from TableE;

Then use sqlcmd to execute it as follows. Since you said the database is remote, use the following syntax (after updating for your server and database instance name).

sqlcmd -S <ComputerName>\<InstanceName> -i C:\Temp\ClearTables.sql

For example, if your remote computer name is SQLSVRBOSTON1 and Database instance name is MyDB1, then the command would be.

sqlcmd -E -S SQLSVRBOSTON1\MyDB1 -i C:\Temp\ClearTables.sql

Also note that -E specifies default authentication. If you have a user name and password to connect, use -U and -P switches.

You will execute all this by opening a CMD command window.

Using a Batch File.

If you want to save it in a batch file and double-click to run it, do it as follows.

Create, and save the ClearTables.bat like so.

echo off
sqlcmd -E -S SQLSVRBOSTON1\MyDB1 -i C:\Temp\ClearTables.sql
set /p delExit=Press the ENTER key to exit...:

Then double-click it to run it. It will execute the commands and wait until you press a key to exit, so you can see the command output.

How to retrieve the hash for the current commit in Git?

Commit hash

git show -s --format=%H

Abbreviated commit hash

git show -s --format=%h

Click here for more git show examples.

Difference between onStart() and onResume()

The book "Hello, Android, Introducing Google's Mobile Development Platform" gives a nice explanation of the life cycle of android apps. Luckily they have the particular chapter online as an excerpt. See the graphic on page 39 in http://media.pragprog.com/titles/eband3/concepts.pdf

By the way, this book is highly recommendable for android beginners!

SQL Query - Change date format in query to DD/MM/YYYY

If I understood your question, try something like this

declare @dd varchar(50)='Jan 30 2013 12:00:00:000AM'

Select convert(varchar,(CONVERT(date,@dd,103)),103)

Update

SELECT
PREFIX_TableName.ColumnName1 AS Name,
PREFIX_TableName.ColumnName2 AS E-Mail,
convert(varchar,(CONVERT(date,PREFIX_TableName.ColumnName3,103)),103) AS TransactionDate,
PREFIX_TableName.ColumnName4 AS OrderNumber

How to manage exceptions thrown in filters in Spring?

I wanted to provide a solution based on the answer of @kopelitsa. The main differences being:

  1. Reusing the controller exception handling by using the HandlerExceptionResolver.
  2. Using Java config over XML config

First, you need to make sure, that you have a class that handles exceptions occurring in a regular RestController/Controller (a class annotated with @RestControllerAdvice or @ControllerAdvice and method(s) annotated with @ExceptionHandler). This handles your exceptions occurring in a controller. Here is an example using the RestControllerAdvice:

@RestControllerAdvice
public class ExceptionTranslator {

    @ExceptionHandler(RuntimeException.class)
    @ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
    public ErrorDTO processRuntimeException(RuntimeException e) {
        return createErrorDTO(HttpStatus.INTERNAL_SERVER_ERROR, "An internal server error occurred.", e);
    }

    private ErrorDTO createErrorDTO(HttpStatus status, String message, Exception e) {
        (...)
    }
}

To reuse this behavior in the Spring Security filter chain, you need to define a Filter and hook it into your security configuration. The filter needs to redirect the exception to the above defined exception handling. Here is an example:

@Component
public class FilterChainExceptionHandler extends OncePerRequestFilter {

    private final Logger log = LoggerFactory.getLogger(getClass());

    @Autowired
    @Qualifier("handlerExceptionResolver")
    private HandlerExceptionResolver resolver;

    @Override
    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
            throws ServletException, IOException {

        try {
            filterChain.doFilter(request, response);
        } catch (Exception e) {
            log.error("Spring Security Filter Chain Exception:", e);
            resolver.resolveException(request, response, null, e);
        }
    }
}

The created filter then needs to be added to the SecurityConfiguration. You need to hook it into the chain very early, because all preceding filter's exceptions won't be caught. In my case, it was reasonable to add it before the LogoutFilter. See the default filter chain and its order in the official docs. Here is an example:

@Configuration
@EnableWebSecurity
public class SecurityConfiguration extends WebSecurityConfigurerAdapter {

    @Autowired
    private FilterChainExceptionHandler filterChainExceptionHandler;

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            .addFilterBefore(filterChainExceptionHandler, LogoutFilter.class)
            (...)
    }

}

How to call a method with a separate thread in Java?

Sometime ago, I had written a simple utility class that uses JDK5 executor service and executes specific processes in the background. Since doWork() typically would have a void return value, you may want to use this utility class to execute it in the background.

See this article where I had documented this utility.

How to beautifully update a JPA entity in Spring Data?

Even better then @Tanjim Rahman answer you can using Spring Data JPA use the method T getOne(ID id)

Customer customerToUpdate = customerRepository.getOne(id);
customerToUpdate.setName(customerDto.getName);
customerRepository.save(customerToUpdate);

Is's better because getOne(ID id) gets you only a reference (proxy) object and does not fetch it from the DB. On this reference you can set what you want and on save() it will do just an SQL UPDATE statement like you expect it. In comparsion when you call find() like in @Tanjim Rahmans answer spring data JPA will do an SQL SELECT to physically fetch the entity from the DB, which you dont need, when you are just updating.

Embedding DLLs in a compiled executable

I use the csc.exe compiler called from a .vbs script.

In your xyz.cs script, add the following lines after the directives (my example is for the Renci SSH):

using System;
using Renci;//FOR THE SSH
using System.Net;//FOR THE ADDRESS TRANSLATION
using System.Reflection;//FOR THE Assembly

//+ref>"C:\Program Files (x86)\Microsoft\ILMerge\Renci.SshNet.dll"
//+res>"C:\Program Files (x86)\Microsoft\ILMerge\Renci.SshNet.dll"
//+ico>"C:\Program Files (x86)\Microsoft CAPICOM 2.1.0.2 SDK\Samples\c_sharp\xmldsig\resources\Traffic.ico"

The ref, res and ico tags will be picked up by the .vbs script below to form the csc command.

Then add the assembly resolver caller in the Main:

public static void Main(string[] args)
{
    AppDomain.CurrentDomain.AssemblyResolve += new ResolveEventHandler(CurrentDomain_AssemblyResolve);
    .

...and add the resolver itself somewhere in the class:

    static Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
    {
        String resourceName = new AssemblyName(args.Name).Name + ".dll";

        using (var stream = Assembly.GetExecutingAssembly().GetManifestResourceStream(resourceName))
        {
            Byte[] assemblyData = new Byte[stream.Length];
            stream.Read(assemblyData, 0, assemblyData.Length);
            return Assembly.Load(assemblyData);
        }

    }

I name the vbs script to match the .cs filename (e.g. ssh.vbs looks for ssh.cs); this makes running the script numerous times a lot easier, but if you aren't an idiot like me then a generic script could pick up the target .cs file from a drag-and-drop:

    Dim name_,oShell,fso
    Set oShell = CreateObject("Shell.Application")
    Set fso = CreateObject("Scripting.fileSystemObject")

    'TAKE THE VBS SCRIPT NAME AS THE TARGET FILE NAME
    '################################################
    name_ = Split(wscript.ScriptName, ".")(0)

    'GET THE EXTERNAL DLL's AND ICON NAMES FROM THE .CS FILE
    '#######################################################
    Const OPEN_FILE_FOR_READING = 1
    Set objInputFile = fso.OpenTextFile(name_ & ".cs", 1)

    'READ EVERYTHING INTO AN ARRAY
    '#############################
    inputData = Split(objInputFile.ReadAll, vbNewline)

    For each strData In inputData

        if left(strData,7)="//+ref>" then 
            csc_references = csc_references & " /reference:" &         trim(replace(strData,"//+ref>","")) & " "
        end if

        if left(strData,7)="//+res>" then 
            csc_resources = csc_resources & " /resource:" & trim(replace(strData,"//+res>","")) & " "
        end if

        if left(strData,7)="//+ico>" then 
            csc_icon = " /win32icon:" & trim(replace(strData,"//+ico>","")) & " "
        end if
    Next

    objInputFile.Close


    'COMPILE THE FILE
    '################
    oShell.ShellExecute "c:\windows\microsoft.net\framework\v3.5\csc.exe", "/warn:1 /target:exe " & csc_references & csc_resources & csc_icon & " " & name_ & ".cs", "", "runas", 2


    WScript.Quit(0)

How to remove the left part of a string?

without having a to write a function, this will split according to list, in this case 'Mr.|Dr.|Mrs.', select everything after split with [1], then split again and grab whatever element. In the case below, 'Morris' is returned.

re.split('Mr.|Dr.|Mrs.', 'Mr. Morgan Morris')[1].split()[1]

Storing Images in DB - Yea or Nay?

Assumption: Application is web enabled/web based

I'm surprised no one has really mentioned this ... delegate it out to others who are specialists -> use a 3rd party image/file hosting provider.

Store your files on a paid online service like

Another StackOverflow threads talking about this here.

This thread explains why you should use a 3rd party hosting provider.

It's so worth it. They store it efficiently. No bandwith getting uploaded from your servers to client requests, etc.

Facebook login "given URL not allowed by application configuration"

I kept getting this error, when using wildcard subdomains with my app. I had the site url set to: http://myapp.com and app domain also to http://myapp.com, and also the same value for the Valid OAuth redirect URIs in the advanced tab of the settings app. I tried different combinations but only setting the http://subdomain.myapp.com as the redirect value worked, of course only for that subdomain.

The solution was to empty the redirect fields, leave it blank, that worked! ;)

How to initialize a static array?

Nope, no difference. It's just syntactic sugar. Arrays.asList(..) creates an additional list.

Restart pods when configmap updates in Kubernetes?

Signalling a pod on config map update is a feature in the works (https://github.com/kubernetes/kubernetes/issues/22368).

You can always write a custom pid1 that notices the confimap has changed and restarts your app.

You can also eg: mount the same config map in 2 containers, expose a http health check in the second container that fails if the hash of config map contents changes, and shove that as the liveness probe of the first container (because containers in a pod share the same network namespace). The kubelet will restart your first container for you when the probe fails.

Of course if you don't care about which nodes the pods are on, you can simply delete them and the replication controller will "restart" them for you.

Difference between /res and /assets directories

Ted Hopp answered this quite nicely. I have been using res/raw for my opengl texture and shader files. I was thinking about moving them to an assets directory to provide a hierarchical organization.

This thread convinced me not to. First, because I like the use of a unique resource id. Second because it's very simple to use InputStream/openRawResource or BitmapFactory to read in the file. Third because it's very useful to be able to use in a portable library.

Is there a way to make a PowerShell script work by double clicking a .ps1 file?

This is based on KoZm0kNoT's answer. I modified it to work across drives.

@echo off
pushd "%~d0"
pushd "%~dp0"
powershell.exe -sta -c "& {.\%~n0.ps1 %*}"
popd
popd

The two pushd/popds are necessary in case the user's cwd is on a different drive. Without the outer set, the cwd on the drive with the script will get lost.

PHP - Check if the page run on Mobile or Desktop browser

There is a very nice PHP library for detecting mobile clients here: http://mobiledetect.net

Using that it's quite easy to only display content for a mobile:

include 'Mobile_Detect.php';
$detect = new Mobile_Detect();

// Check for any mobile device.
if ($detect->isMobile()){
   // mobile content
}
else {
   // other content for desktops
}

The representation of if-elseif-else in EL using JSF

One possible solution is:

<h:panelGroup rendered="#{bean.row == 10}">
    <div class="text-success">
        <h:outputText value="#{bean.row}"/>
    </div>
</h:panelGroup>

Trying to git pull with error: cannot open .git/FETCH_HEAD: Permission denied

Set permission to your current user by running the command

$ sudo chown -R <username> .git/

how to store Image as blob in Sqlite & how to retrieve it?

byte[] byteArray = rs.getBytes("columnname");  

Bitmap bm = BitmapFactory.decodeByteArray(byteArray, 0 ,byteArray.length);

How to remove trailing whitespace in code, using another script?

You don't see any output from the print statements because FileInput redirects stdout to the input file when the keyword argument inplace=1 is given. This causes the input file to effectively be rewritten and if you look at it afterwards the lines in it will indeed have no trailing or leading whitespace in them (except for the newline at the end of each which the print statement adds back).

If you only want to remove trailing whitespace, you should use rstrip() instead of strip(). Also note that the if lines == '': continue is causing blank lines to be completely removed (regardless of whether strip or rstrip gets used).

Unless your intent is to rewrite the input file, you should probably just use for line in open(filename):. Otherwise you can see what's being written to the file by simultaneously echoing the output to sys.stderr using something like the following:

import fileinput
import sys

for line in (line.rstrip() for line in
                fileinput.FileInput("test.txt", inplace=1)):
    if line:
        print line
        print >>sys.stderr, line

Spring Data JPA findOne() change to Optional how to use this?

The method has been renamed to findById(…) returning an Optional so that you have to handle absence yourself:

Optional<Foo> result = repository.findById(…);

result.ifPresent(it -> …); // do something with the value if present
result.map(it -> …); // map the value if present
Foo foo = result.orElse(null); // if you want to continue just like before

How to Copy Contents of One Canvas to Another Canvas Locally

@robert-hurst has a cleaner approach.

However, this solution may also be used, in places when you actually want to have a copy of Data Url after copying. For example, when you are building a website that uses lots of image/canvas operations.

    // select canvas elements
    var sourceCanvas = document.getElementById("some-unique-id");
    var destCanvas = document.getElementsByClassName("some-class-selector")[0];

    //copy canvas by DataUrl
    var sourceImageData = sourceCanvas.toDataURL("image/png");
    var destCanvasContext = destCanvas.getContext('2d');

    var destinationImage = new Image;
    destinationImage.onload = function(){
      destCanvasContext.drawImage(destinationImage,0,0);
    };
    destinationImage.src = sourceImageData;

Bloomberg BDH function with ISIN

I had the same problem. Here's what I figured out:

=BDP(A1&"@BGN Corp", "Issuer_parent_eqy_ticker")

A1 being the ISINs. This will return the ticker number. Then just use the ticker number to get the price.

How to convert integer to string in C?

Use sprintf():

int someInt = 368;
char str[12];
sprintf(str, "%d", someInt);

All numbers that are representable by int will fit in a 12-char-array without overflow, unless your compiler is somehow using more than 32-bits for int. When using numbers with greater bitsize, e.g. long with most 64-bit compilers, you need to increase the array size—at least 21 characters for 64-bit types.

CSS text-overflow: ellipsis; not working?

You just add one line css:

.app a {
   display: inline-block;
}

SELECT INTO USING UNION QUERY

You can also try:

create table new_table as
select * from table1
union
select * from table2

Use jquery to set value of div tag

To put text, use .text('text')

If you want to use .html(SomeValue), SomeValue should have html tags that can be inside a div it must work too.

Just check your script location, as farzad said.

Reference: .html and text

Calendar date to yyyy-MM-dd format in java

I found this code where date is compared in a format to compare with date field in database...may be this might be helpful to you...

When you convert the string to date using simpledateformat, it is hard to compare with the Date field in mysql databases.

So convert the java string date in the format using select STR_to_DATE('yourdate','%m/%d/%Y') --> in this format, then you will get the exact date format of mysql date field.

http://javainfinite.com/java/java-convert-string-to-date-and-compare/

Linq Select Group By

var result = priceLog.GroupBy(s => s.LogDateTime.ToString("MMM yyyy")).Select(grp => new PriceLog() { LogDateTime = Convert.ToDateTime(grp.Key), Price = (int)grp.Average(p => p.Price) }).ToList();

I have converted it to int because my Price field was int and Average method return double .I hope this will help

PHP Get name of current directory

For EXAMPLE

Your Path = /home/serverID_name/www/your_route_Dir/

THIS_is_the_DIR_I_Want

A Soultion that WORKS:

$url = dirname(\__FILE__);
$array = explode('\\\',$url);
$count = count($array);
echo $array[$count-1];

delete all from table

There is a mySQL bug report from 2004 that still seems to have some validity. It seems that in 4.x, this was fastest:

DROP table_name
CREATE TABLE table_name

TRUNCATE table_name was DELETE FROM internally back then, providing no performance gain.

This seems to have changed, but only in 5.0.3 and younger. From the bug report:

[11 Jan 2005 16:10] Marko Mäkelä

I've now implemented fast TRUNCATE TABLE, which will hopefully be included in MySQL 5.0.3.

ImproperlyConfigured: You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings

In my case it was the use of the call_command module that posed a problem.
I added set DJANGO_SETTINGS_MODULE=mysite.settings but it didn't work.

I finally found it:

add these lines at the top of the script, and the order matters.

import os
os.environ.setdefault("DJANGO_SETTINGS_MODULE", "mysite.settings")

import django
django.setup()

from django.core.management import call_command

How to make HTML Text unselectable

You can't do this with plain vanilla HTML, so JSF can't do much for you here as well.

If you're targeting decent browsers only, then just make use of CSS3:

.unselectable {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}
<label class="unselectable">Unselectable label</label>

If you'd like to cover older browsers as well, then consider this JavaScript fallback:

<!doctype html>
<html lang="en">
    <head>
        <title>SO question 2310734</title>
        <script>
            window.onload = function() {
                var labels = document.getElementsByTagName('label');
                for (var i = 0; i < labels.length; i++) {
                    disableSelection(labels[i]);
                }
            };
            function disableSelection(element) {
                if (typeof element.onselectstart != 'undefined') {
                    element.onselectstart = function() { return false; };
                } else if (typeof element.style.MozUserSelect != 'undefined') {
                    element.style.MozUserSelect = 'none';
                } else {
                    element.onmousedown = function() { return false; };
                }
            }
        </script>
    </head>
    <body>
        <label>Try to select this</label>
    </body>
</html>

If you're already using jQuery, then here's another example which adds a new function disableSelection() to jQuery so that you can use it anywhere in your jQuery code:

<!doctype html>
<html lang="en">
    <head>
        <title>SO question 2310734 with jQuery</title>
        <script src="http://code.jquery.com/jquery-latest.min.js"></script>
        <script>
            $.fn.extend({ 
                disableSelection: function() { 
                    this.each(function() { 
                        if (typeof this.onselectstart != 'undefined') {
                            this.onselectstart = function() { return false; };
                        } else if (typeof this.style.MozUserSelect != 'undefined') {
                            this.style.MozUserSelect = 'none';
                        } else {
                            this.onmousedown = function() { return false; };
                        }
                    }); 
                } 
            });

            $(document).ready(function() {
                $('label').disableSelection();            
            });
        </script>
    </head>
    <body>
        <label>Try to select this</label>
    </body>
</html>

PostgreSQL: Why psql can't connect to server?

Verify that Postgres is running using:

ps -ef | grep postgres
root@959dca34cc6d:/var/lib/edb# ps -ef|grep postgres
enterpr+    476  1  0 06:38 ?        00:00:00 /usr/lib/edb-as/11/bin/edb-postgres -D /var/lib/edb-as/11/main2 -c config_file=/etc/edb-as/11/main2/postgresql.conf

Check for data directory and postgresql.conf.

In my case data directory in -D was different than that in postgresql.conf

So I changed the data directory in postgresql.conf and it worked.

How to define constants in Visual C# like #define in C?

In C#, per MSDN library, we have the "const" keyword that does the work of the "#define" keyword in other languages.

"...when the compiler encounters a constant identifier in C# source code (for example, months), it substitutes the literal value directly into the intermediate language (IL) code that it produces." ( https://msdn.microsoft.com/en-us/library/ms173119.aspx )

Initialize constants at time of declaration since there is no changing them.

public const int cMonths = 12;

Building executable jar with maven?

If you don't want execute assembly goal on package, you can use next command:

mvn package assembly:single

Here package is keyword.

Get bytes from std::string in C++

If this is just plain vanilla C, then:

strcpy(buffer, text.c_str());

Assuming that buffer is allocated and large enough to hold the contents of 'text', which is the assumption in your original code.

If encrypt() takes a 'const char *' then you can use

encrypt(text.c_str())

and you do not need to copy the string.

How do you round a float to 2 decimal places in JRuby?

Float#round can take a parameter in Ruby 1.9, not in Ruby 1.8. JRuby defaults to 1.8, but it is capable of running in 1.9 mode.

How to do a subquery in LINQ?

There is no subquery needed with this statement, which is better written as

select u.* 
from Users u, CompanyRolesToUsers c
where u.Id = c.UserId        --join just specified here, perfectly fine
and u.lastname like '%fra%'
and c.CompanyRoleId in (2,3,4)

or

select u.* 
from Users u inner join CompanyRolesToUsers c
             on u.Id = c.UserId    --explicit "join" statement, no diff from above, just preference
where u.lastname like '%fra%'
  and c.CompanyRoleId in (2,3,4)

That being said, in LINQ it would be

from u in Users
from c in CompanyRolesToUsers 
where u.Id == c.UserId &&
      u.LastName.Contains("fra") &&
      selectedRoles.Contains(c.CompanyRoleId)
select u

or

from u in Users
join c in CompanyRolesToUsers 
       on u.Id equals c.UserId
where u.LastName.Contains("fra") &&
      selectedRoles.Contains(c.CompanyRoleId)
select u

Which again, are both respectable ways to represent this. I prefer the explicit "join" syntax in both cases myself, but there it is...

Best ways to teach a beginner to program?

Something to consider ... not everyone is capable of programming:

Some people just cannot get past things like:

A = 1

B = 2

A = B

(these people will still think A = 1)

Jeff has talked about this too. In fact, my example is in the link (and explained, to boot).

How to limit the number of selected checkboxes?

$('.checkbox').click(function(){
  if ($('.checkbox:checked').length >= 3) {
    $(".checkbox").not(":checked").attr("disabled",true);
  }
  else 
    $(".checkbox").not(":checked").removeAttr('disabled');
});

i used this.

Ant error when trying to build file, can't find tools.jar?

I was also getting the same problem, but i uninstalled all updates of java and now it is working very fine....

How to add items into a numpy array

np.insert can also be used for the purpose

import numpy as np
a = np.array([[1, 3, 4],
              [1, 2, 3],
              [1, 2, 1]])
x = 5
index = 3 # the position for x to be inserted before
np.insert(a, index, x, axis=1)
array([[1, 3, 4, 5],
       [1, 2, 3, 5],
       [1, 2, 1, 5]])

index can also be a list/tuple

>>> index = [1, 1, 3] # equivalently (1, 1, 3)
>>> np.insert(a, index, x, axis=1)
array([[1, 5, 5, 3, 4, 5],
       [1, 5, 5, 2, 3, 5],
       [1, 5, 5, 2, 1, 5]])

or a slice

>>> index = slice(0, 3)
>>> np.insert(a, index, x, axis=1)
array([[5, 1, 5, 3, 5, 4],
       [5, 1, 5, 2, 5, 3],
       [5, 1, 5, 2, 5, 1]])

Python function pointer

It's much nicer to be able to just store the function itself, since they're first-class objects in python.

import mypackage

myfunc = mypackage.mymodule.myfunction
myfunc(parameter1, parameter2)

But, if you have to import the package dynamically, then you can achieve this through:

mypackage = __import__('mypackage')
mymodule = getattr(mypackage, 'mymodule')
myfunction = getattr(mymodule, 'myfunction')

myfunction(parameter1, parameter2)

Bear in mind however, that all of that work applies to whatever scope you're currently in. If you don't persist them somehow, you can't count on them staying around if you leave the local scope.

PHP Create and Save a txt file to root directory

It's creating the file in the same directory as your script. Try this instead.

$content = "some text here";
$fp = fopen($_SERVER['DOCUMENT_ROOT'] . "/myText.txt","wb");
fwrite($fp,$content);
fclose($fp);

Modulo operator in Python

same as a normal modulo 3.14 % 6.28 = 3.14, just like 3.14%4 =3.14 3.14%2 = 1.14 (the remainder...)

Running java with JAVA_OPTS env variable has no effect

You can setup _JAVA_OPTIONS instead of JAVA_OPTS. This should work without $_JAVA_OPTIONS.

PDF files do not open in Internet Explorer with Adobe Reader 10.0 - users get an empty gray screen. How can I fix this for my users?

Hm, would it be possible to simply do this:

The first time your user opens a pdf, using Javascript you make a popout that basically says "If you cannot see your document, please click HERE". Make "HERE" a big button where it will explain to your user what's the problem. Also make another button "everything's fine". If the user clicks on this one, you remember it, so it isn't displayed in the future.

I'm trying to be practical. Going to great lengths trying to solve this kind of problem "properly" for a small subset of Adobe Reader versions doesn't sound very productive to me.

Google.com and clients1.google.com/generate_204

Google is using this to detect whether the device is online or in captive portal.

Shill, the connection manager for Chromium OS, attempts to detect services that are within a captive portal whenever a service transitions to the ready state. This determination of being in a captive portal or being online is done by attempting to retrieve the webpage http://clients3.google.com/generate_204. This well known URL is known to return an empty page with an HTTP status 204. If for any reason the web page is not returned, or an HTTP response other than 204 is received, then shill marks the service as being in the portal state.

Here is the relevant explanation from the Google Chrome Privacy Whitepaper:

In the event that Chrome detects SSL connection timeouts, certificate errors, or other network issues that might be caused by a captive portal (a hotel's WiFi network, for instance), Chrome will make a cookieless request to http://www.gstatic.com/generate_204 and check the response code. If that request is redirected, Chrome will open the redirect target in a new tab on the assumption that it's a login page. Requests to the captive portal detection page are not logged.

More info: http://www.chromium.org/chromium-os/chromiumos-design-docs/network-portal-detection

WPF C# button style

To solve your question definitely need to use the Style and Template for the Button. But how exactly does he look like? Decisions may be several. For example, Button are two texts to better define the relevant TextBlocks? Can be directly in the template, but then use the buttons will be limited, because the template can be only one ContentPresenter. I decided to do things differently, to identify one ContentPresenter with an icon in the form of a Path, and the content is set using the buttons on the side.

The style:

<Style TargetType="{x:Type Button}">
    <Setter Property="Background" Value="#373737" />
    <Setter Property="Foreground" Value="White" />
    <Setter Property="FontSize" Value="15" />
    <Setter Property="SnapsToDevicePixels" Value="True" />

    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Button}">
                <Border CornerRadius="4" Background="{TemplateBinding Background}">
                    <Grid>
                        <Path x:Name="PathIcon" Width="15" Height="25" Stretch="Fill" Fill="#4C87B3" HorizontalAlignment="Left" Margin="17,0,0,0" Data="F1 M 30.0833,22.1667L 50.6665,37.6043L 50.6665,38.7918L 30.0833,53.8333L 30.0833,22.1667 Z "/>
                        <ContentPresenter x:Name="MyContentPresenter" Content="{TemplateBinding Content}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,0,0,0" />                                
                    </Grid>
                </Border>

                <ControlTemplate.Triggers>
                    <Trigger Property="IsMouseOver" Value="True">
                        <Setter Property="Background" Value="#E59400" />
                        <Setter Property="Foreground" Value="White" />
                        <Setter TargetName="PathIcon" Property="Fill" Value="Black" />
                    </Trigger>

                    <Trigger Property="IsPressed" Value="True">
                        <Setter Property="Background" Value="OrangeRed" />
                        <Setter Property="Foreground" Value="White" />
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

Sample of using:

<Button Width="200" Height="50" VerticalAlignment="Top" Margin="0,20,0,0" />
    <Button.Content>
        <StackPanel>
            <TextBlock Text="Watch Now" FontSize="20" />
            <TextBlock Text="Duration: 50m" FontSize="12" Foreground="Gainsboro" />
        </StackPanel>
    </Button.Content>
</Button>

Output

enter image description here

It is best to StackPanel determine the Resources and set the Button so:

<Window.Resources>
    <StackPanel x:Key="MyStackPanel">
        <TextBlock Name="MainContent" Text="Watch Now" FontSize="20" />
        <TextBlock Name="DurationValue" Text="Duration: 50m" FontSize="12" Foreground="Gainsboro" />
    </StackPanel>
</Window.Resources>

<Button Width="200" Height="50" Content="{StaticResource MyStackPanel}" VerticalAlignment="Top" Margin="0,20,0,0" />

The question remains with setting the value for TextBlock Duration, because this value must be dynamic. I implemented it using attached DependencyProperty. Set it to the window, like that:

<Window Name="MyWindow" local:MyDependencyClass.CurrentDuration="Duration: 50m" ... />

Using in TextBlock:

<TextBlock Name="DurationValue" Text="{Binding ElementName=MyWindow, Path=(local:MyDependencyClass.CurrentDuration)}" FontSize="12" Foreground="Gainsboro" />

In fact, there is no difference for anyone to determine the attached DependencyProperty, because it is the predominant feature.

Example of set value:

private void Button_Click(object sender, RoutedEventArgs e)
{
    MyDependencyClass.SetCurrentDuration(MyWindow, "Duration: 101m");
}

A complete listing of examples:

XAML

<Window x:Class="ButtonHelp.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="clr-namespace:ButtonHelp"
    Name="MyWindow"
    Title="MainWindow" Height="350" Width="525"
    WindowStartupLocation="CenterScreen"
    local:MyDependencyClass.CurrentDuration="Duration: 50m">

<Window.Resources>
    <Style TargetType="{x:Type Button}">
        <Setter Property="Background" Value="#373737" />
        <Setter Property="Foreground" Value="White" />
        <Setter Property="FontSize" Value="15" />
        <Setter Property="FontFamily" Value="./#Segoe UI" />
        <Setter Property="SnapsToDevicePixels" Value="True" />

        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type Button}">
                    <Border CornerRadius="4" Background="{TemplateBinding Background}">
                        <Grid>
                            <Path x:Name="PathIcon" Width="15" Height="25" Stretch="Fill" Fill="#4C87B3" HorizontalAlignment="Left" Margin="17,0,0,0" Data="F1 M 30.0833,22.1667L 50.6665,37.6043L 50.6665,38.7918L 30.0833,53.8333L 30.0833,22.1667 Z "/>
                            <ContentPresenter x:Name="MyContentPresenter" Content="{TemplateBinding Content}" HorizontalAlignment="Center" VerticalAlignment="Center" Margin="0,0,0,0" />                                
                        </Grid>
                    </Border>

                    <ControlTemplate.Triggers>
                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter Property="Background" Value="#E59400" />
                            <Setter Property="Foreground" Value="White" />
                            <Setter TargetName="PathIcon" Property="Fill" Value="Black" />
                        </Trigger>

                        <Trigger Property="IsPressed" Value="True">
                            <Setter Property="Background" Value="OrangeRed" />
                            <Setter Property="Foreground" Value="White" />
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

    <StackPanel x:Key="MyStackPanel">
        <TextBlock Name="MainContent" Text="Watch Now" FontSize="20" />
        <TextBlock Name="DurationValue" Text="{Binding ElementName=MyWindow, Path=(local:MyDependencyClass.CurrentDuration)}" FontSize="12" Foreground="Gainsboro" />
    </StackPanel>
</Window.Resources>

<Grid>        
    <Button Width="200" Height="50" Content="{StaticResource MyStackPanel}" VerticalAlignment="Top" Margin="0,20,0,0" />

    <Button Content="Set some duration" Style="{x:Null}" Width="140" Height="30" VerticalAlignment="Top" HorizontalAlignment="Left" Click="Button_Click" />
</Grid>

Code behind

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        MyDependencyClass.SetCurrentDuration(MyWindow, "Duration: 101m");
    }
}

public class MyDependencyClass : DependencyObject
{
    public static readonly DependencyProperty CurrentDurationProperty;        

    public static void SetCurrentDuration(DependencyObject DepObject, string value)
    {
        DepObject.SetValue(CurrentDurationProperty, value);
    }

    public static string GetCurrentDuration(DependencyObject DepObject)
    {
        return (string)DepObject.GetValue(CurrentDurationProperty);
    }

    static MyDependencyClass()
    {
        PropertyMetadata MyPropertyMetadata = new PropertyMetadata("Duration: 0m");

        CurrentDurationProperty = DependencyProperty.RegisterAttached("CurrentDuration",
                                                            typeof(string),
                                                            typeof(MyDependencyClass),
                                                            MyPropertyMetadata);
    }
}

Convert DateTime to long and also the other way around

   long dateTime = DateTime.Now.Ticks;
   Console.WriteLine(dateTime);
   Console.WriteLine(new DateTime(dateTime));
   Console.ReadKey();

Why does .json() return a promise?

In addition to the above answers here is how you might handle a 500 series response from your api where you receive an error message encoded in json:

function callApi(url) {
  return fetch(url)
    .then(response => {
      if (response.ok) {
        return response.json().then(response => ({ response }));
      }

      return response.json().then(error => ({ error }));
    })
  ;
}

let url = 'http://jsonplaceholder.typicode.com/posts/6';

const { response, error } = callApi(url);
if (response) {
  // handle json decoded response
} else {
  // handle json decoded 500 series response
}

file_get_contents() Breaks Up UTF-8 Characters

In Turkish language, mb_convert_encoding or any other charset conversion did not work.

And also urlencode did not work because of space char converted to + char. It must be %20 for percent encoding.

This one worked!

   $url = rawurlencode($url);
   $url = str_replace("%3A", ":", $url);
   $url = str_replace("%2F", "/", $url);

   $data = file_get_contents($url);

How to convert AAR to JAR

Resource based .aar-projects

Finding the classes.jar file inside the .aar file is pretty trivial. However, that approach does not work, if the .aar-project defined some resources (example: R.layout.xyz)

  • Therefore deaar from CommonsGuy helped me to get a valid ADT-friendly project out of an .aar-file. In my case I converted subsampling-scale-image-view. It took me about an hour to set up ruby on my PC.

  • Another approach is using android-maven-plugin for Eclipse/ADT as CommonsGuy writes in his blog.

  • Yet another approach could be, just cloning the whole desired project as source from git and import it as "Existing Android project"

Pandas DataFrame to List of Dictionaries

If you are interested in only selecting one column this will work.

df[["item1"]].to_dict("records")

The below will NOT work and produces a TypeError: unsupported type: . I believe this is because it is trying to convert a series to a dict and not a Data Frame to a dict.

df["item1"].to_dict("records")

I had a requirement to only select one column and convert it to a list of dicts with the column name as the key and was stuck on this for a bit so figured I'd share.

How do I perform a Perl substitution on a string while keeping the original?

Another pre-5.14 solution: http://www.perlmonks.org/?node_id=346719 (see japhy's post)

As his approach uses map, it also works well for arrays, but requires cascading map to produce a temporary array (otherwise the original would be modified):

my @orig = ('this', 'this sucks', 'what is this?');
my @list = map { s/this/that/; $_ } map { $_ } @orig;
# @orig unmodified

C++ terminate called without an active exception

First you define a thread. And if you never call join() or detach() before calling the thread destructor, the program will abort.

As follows, calling a thread destructor without first calling join (to wait for it to finish) or detach is guarenteed to immediately call std::terminate and end the program.

Either implicitly detaching or joining a joinable() thread in its destructor could result in difficult to debug correctness (for detach) or performance (for join) bugs encountered only when an exception is raised. Thus the programmer must ensure that the destructor is never executed while the thread is still joinable.

Regex how to match an optional character

Use

[A-Z]?

to make the letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)

You could improve your regex to

^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])[0-9]{3}([0-9]{4})([0-9]{2})([0-9]{2})

And, since in most regex dialects, \d is the same as [0-9]:

^(\d{5})+\s+([A-Z]?)\s+([A-Z])(\d{3})(\d{3})([A-Z]{3})([A-Z]{3})\s+([A-Z])\d{3}(\d{4})(\d{2})(\d{2})

But: do you really need 11 separate capturing groups? And if so, why don't you capture the fourth-to-last group of digits?

How to get Android application id?

Package name is your android app id .

String appId = BuildConfig.APPLICATION_ID

Or

https://play.google.com/store/apps/details?id=com.whatsapp

App Id = com.whatsapp

Swift add icon/image in UITextField

You can put this function your global file or above your class so you can access it in entire application. After this procedure you can call this function as per your requirement in application.

        func SetLeftSIDEImage(TextField: UITextField, ImageName: String){

                let leftImageView = UIImageView()
                leftImageView.contentMode = .scaleAspectFit

                let leftView = UIView()

                leftView.frame = CGRect(x: 20, y: 0, width: 30, height: 20)
                leftImageView.frame = CGRect(x: 13, y: 0, width: 15, height: 20)
                TextField.leftViewMode = .always
                TextField.leftView = leftView

                let image = UIImage(named: ImageName)?.withRenderingMode(.alwaysTemplate)
                leftImageView.image = image
                leftImageView.tintColor = UIColor(red: 106/255, green: 79/255, blue: 131/255, alpha: 1.0)
                leftImageView.tintColorDidChange()

                leftView.addSubview(leftImageView)
            }

            SetLeftSIDEImage(TextField: Your_textField, ImageName: “YourImageName”) // call function

How to set TextView textStyle such as bold, italic

Simply if you want to make text bold. write this line in your layout in text view property

android:textStyle="bold"

Speed tradeoff of Java's -Xms and -Xmx options

It depends on the GC your java is using. Parallel GCs might work better on larger memory settings - I'm no expert on that though.

In general, if you have larger memory the less frequent it needs to be GC-ed - there is lots of room for garbage. However, when it comes to a GC, the GC has to work on more memory - which in turn might be slower.

Some dates recognized as dates, some dates not recognized. Why?

It's not that hard...

Check out this forum post:

http://www.pcreview.co.uk/forums/excel-not-recognizing-dates-dates-t3139469.html

The steps in short:

  1. Select only the column of "dates"
  2. Click Data > Text to Columns
  3. Click Next
  4. Click Next
  5. In step 3 of the wizard, check "Date" under Col data format, then choose: "DMY" from the droplist.
  6. Click Finish

PHP - If variable is not empty, echo some html code

You're using isset, what isset does is check if the variable is set ('exists') and is not NULL. What you're looking for is empty, which checks if a variable is empty or not, even if it's set. To check what is empty and what is not take a look at:

http://php.net/manual/en/function.empty.php

Also check http://php.net/manual/en/function.isset.php for what isset does exactly, so you understand why it doesn't do what you expect it to do.

How to remove padding around buttons in Android?

That's not padding, it's the shadow around the button in its background drawable. Create your own background and it will disappear.

Where to find extensions installed folder for Google Chrome on Mac?

The default locations of Chrome's profile directory are defined at http://www.chromium.org/user-experience/user-data-directory. For Chrome on Mac, it's

~/Library/Application\ Support/Google/Chrome/Default

The actual location can be different, by setting the --user-data-dir=path/to/directory flag.
If only one user is registered in Chrome, look in the Default/Extensions subdirectory. Otherwise, look in the <profile user name>/Extensions directory.

If that didn't help, you can always do a custom search.

  1. Go to chrome://extensions/, and find out the ID of an extension (32 lowercase letters) (if not done already, activate "Developer mode" first).

  2. Open the terminal, cd to the directory which is most likely a parent of your Chrome profile (if unsure, try ~ then /).

  3. Run find . -type d -iname "<EXTENSION ID HERE>", for example:

    find . -type d -iname jifpbeccnghkjeaalbbjmodiffmgedin
    

    Result:

    ./Library/Application Support/Google/Chrome/Default/Extensions/jifpbeccnghkjeaalbbjmodiffmgedin

jQuery.ajax returns 400 Bad Request

I was getting the 400 Bad Request error, even after setting:

contentType: "application/json",
dataType: "json"

The issue was with the type of a property passed in the json object, for the data property in the ajax request object.
To figure out the issue, I added an error handler and then logged the error to the console. Console log will clearly show validation errors for the properties if any.

This was my initial code:

var data = {
    "TestId": testId,
    "PlayerId": parseInt(playerId),
    "Result": result
};

var url = document.location.protocol + "//" + document.location.host + "/api/tests"
$.ajax({
    url: url,
    method: "POST",
    contentType: "application/json",
    data: JSON.stringify(data), // issue with a property type in the data object
    dataType: "json",
    error: function (e) {
        console.log(e); // logging the error object to console
    },
    success: function () {
        console.log('Success saving test result');
    }
});

Now after making the request, I checked the console tab in the browser development tool.
It looked like this: enter image description here

responseJSON.errors[0] clearly shows a validation error: The JSON value could not be converted to System.String. Path: $.TestId, which means I have to convert TestId to a string in the data object, before making the request.

Changing the data object creation like below fixed the issue for me:

var data = {
        "TestId": String(testId), //converting testId to a string
        "PlayerId": parseInt(playerId),
        "Result": result
};

I assume other possible errors could also be identified by logging and inspecting the error object.

Error CS2001: Source file '.cs' could not be found

They are likely still referenced by the project file. Make sure they are deleted using the Solution Explorer in Visual Studio - it should show them as being missing (with an exclamation mark).

Difference between __getattr__ vs __getattribute__

New-style classes are ones that subclass "object" (directly or indirectly). They have a __new__ class method in addition to __init__ and have somewhat more rational low-level behavior.

Usually, you'll want to override __getattr__ (if you're overriding either), otherwise you'll have a hard time supporting "self.foo" syntax within your methods.

Extra info: http://www.devx.com/opensource/Article/31482/0/page/4

The specified child already has a parent. You must call removeView() on the child's parent first

I encountered this error while there is an invisible view in an activity xml layout. At that time it was not used in my case so I have removed it and the crash is not seen anymore.

In Java, how to append a string more efficiently?

java.lang.StringBuilder. Use int constructor to create an initial size.

Are list-comprehensions and functional functions faster than "for loops"?

I modified @Alisa's code and used cProfile to show why list comprehension is faster:

from functools import reduce
import datetime

def reduce_(numbers):
    return reduce(lambda sum, next: sum + next * next, numbers, 0)

def for_loop(numbers):
    a = []
    for i in numbers:
        a.append(i*2)
    a = sum(a)
    return a

def map_(numbers):
    sqrt = lambda x: x*x
    return sum(map(sqrt, numbers))

def list_comp(numbers):
    return(sum([i*i for i in numbers]))

funcs = [
        reduce_,
        for_loop,
        map_,
        list_comp
        ]

if __name__ == "__main__":
    # [1, 2, 5, 3, 1, 2, 5, 3]
    import cProfile
    for f in funcs:
        print('=' * 25)
        print("Profiling:", f.__name__)
        print('=' * 25)
        pr = cProfile.Profile()
        for i in range(10**6):
            pr.runcall(f, [1, 2, 5, 3, 1, 2, 5, 3])
        pr.create_stats()
        pr.print_stats()

Here's the results:

=========================
Profiling: reduce_
=========================
         11000000 function calls in 1.501 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
  1000000    0.162    0.000    1.473    0.000 profiling.py:4(reduce_)
  8000000    0.461    0.000    0.461    0.000 profiling.py:5(<lambda>)
  1000000    0.850    0.000    1.311    0.000 {built-in method _functools.reduce}
  1000000    0.028    0.000    0.028    0.000 {method 'disable' of '_lsprof.Profiler' objects}


=========================
Profiling: for_loop
=========================
         11000000 function calls in 1.372 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
  1000000    0.879    0.000    1.344    0.000 profiling.py:7(for_loop)
  1000000    0.145    0.000    0.145    0.000 {built-in method builtins.sum}
  8000000    0.320    0.000    0.320    0.000 {method 'append' of 'list' objects}
  1000000    0.027    0.000    0.027    0.000 {method 'disable' of '_lsprof.Profiler' objects}


=========================
Profiling: map_
=========================
         11000000 function calls in 1.470 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
  1000000    0.264    0.000    1.442    0.000 profiling.py:14(map_)
  8000000    0.387    0.000    0.387    0.000 profiling.py:15(<lambda>)
  1000000    0.791    0.000    1.178    0.000 {built-in method builtins.sum}
  1000000    0.028    0.000    0.028    0.000 {method 'disable' of '_lsprof.Profiler' objects}


=========================
Profiling: list_comp
=========================
         4000000 function calls in 0.737 seconds

   Ordered by: standard name

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
  1000000    0.318    0.000    0.709    0.000 profiling.py:18(list_comp)
  1000000    0.261    0.000    0.261    0.000 profiling.py:19(<listcomp>)
  1000000    0.131    0.000    0.131    0.000 {built-in method builtins.sum}
  1000000    0.027    0.000    0.027    0.000 {method 'disable' of '_lsprof.Profiler' objects}

IMHO:

  • reduce and map are in general pretty slow. Not only that, using sum on the iterators that map returned is slow, compared to suming a list
  • for_loop uses append, which is of course slow to some extent
  • list-comprehension not only spent the least time building the list, it also makes sum much quicker, in contrast to map

CakePHP select default value in SELECT input

the third parameter should be like array('selected' =>value)

What is an "index out of range" exception, and how do I fix it?

Why does this error occur?

Because you tried to access an element in a collection, using a numeric index that exceeds the collection's boundaries.

The first element in a collection is generally located at index 0. The last element is at index n-1, where n is the Size of the collection (the number of elements it contains). If you attempt to use a negative number as an index, or a number that is larger than Size-1, you're going to get an error.

How indexing arrays works

When you declare an array like this:

var array = new int[6]

The first and last elements in the array are

var firstElement = array[0];
var lastElement = array[5];

So when you write:

var element = array[5];

you are retrieving the sixth element in the array, not the fifth one.

Typically, you would loop over an array like this:

for (int index = 0; index < array.Length; index++)
{
    Console.WriteLine(array[index]);
}

This works, because the loop starts at zero, and ends at Length-1 because index is no longer less than Length.

This, however, will throw an exception:

for (int index = 0; index <= array.Length; index++)
{
    Console.WriteLine(array[index]);
}

Notice the <= there? index will now be out of range in the last loop iteration, because the loop thinks that Length is a valid index, but it is not.

How other collections work

Lists work the same way, except that you generally use Count instead of Length. They still start at zero, and end at Count - 1.

for (int index = 0; i < list.Count; index++)
{
    Console.WriteLine(list[index]);
} 

However, you can also iterate through a list using foreach, avoiding the whole problem of indexing entirely:

foreach (var element in list)
{
    Console.WriteLine(element.ToString());
}

You cannot index an element that hasn't been added to a collection yet.

var list = new List<string>();
list.Add("Zero");
list.Add("One");
list.Add("Two");
Console.WriteLine(list[3]);  // Throws exception.

PHP: How to get referrer URL?

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

How to convert a Drawable to a Bitmap?

Android provides a non straight foward solution: BitmapDrawable. To get the Bitmap , we'll have to provide the resource id R.drawable.flower_pic to the a BitmapDrawable and then cast it to a Bitmap.

Bitmap bm = ((BitmapDrawable) getResources().getDrawable(R.drawable.flower_pic)).getBitmap();

How to force a view refresh without having it trigger automatically from an observable?

I have created a JSFiddle with my bindHTML knockout binding handler here: https://jsfiddle.net/glaivier/9859uq8t/

First, save the binding handler into its own (or a common) file and include after Knockout.

If you use this switch your bindings to this:

<div data-bind="bindHTML: htmlValue"></div>

OR

<!-- ko bindHTML: htmlValue --><!-- /ko -->

What are all codecs and formats supported by FFmpeg?

You can see the list of supported codecs in the official documentation:

Supported video codecs

Supported audio codecs

How to get all registered routes in Express?

Need some adjusts but should work for Express v4. Including those routes added with .use().

function listRoutes(routes, stack, parent){

  parent = parent || '';
  if(stack){
    stack.forEach(function(r){
      if (r.route && r.route.path){
        var method = '';

        for(method in r.route.methods){
          if(r.route.methods[method]){
            routes.push({method: method.toUpperCase(), path: parent + r.route.path});
          }
        }       

      } else if (r.handle && r.handle.name == 'router') {
        const routerName = r.regexp.source.replace("^\\","").replace("\\/?(?=\\/|$)","");
        return listRoutes(routes, r.handle.stack, parent + routerName);
      }
    });
    return routes;
  } else {
    return listRoutes([], app._router.stack);
  }
}

//Usage on app.js
const routes = listRoutes(); //array: ["method: path", "..."]

edit: code improvements

How to get the name of the current method from code

Does this not work?

System.Reflection.MethodBase.GetCurrentMethod()

Returns a MethodBase object representing the currently executing method.

Namespace: System.Reflection

Assembly: mscorlib (in mscorlib.dll)

http://msdn.microsoft.com/en-us/library/system.reflection.methodbase.getcurrentmethod.aspx

How to check for the type of a template parameter?

Use is_same:

#include <type_traits>

template <typename T>
void foo()
{
    if (std::is_same<T, animal>::value) { /* ... */ }  // optimizable...
}

Usually, that's a totally unworkable design, though, and you really want to specialize:

template <typename T> void foo() { /* generic implementation  */ }

template <> void foo<animal>()   { /* specific for T = animal */ }

Note also that it's unusual to have function templates with explicit (non-deduced) arguments. It's not unheard of, but often there are better approaches.

jQuery document.createElement equivalent?

UPDATE

As of the latest versions of jQuery, the following method doesn't assign properties passed in the second Object

Previous answer

I feel using document.createElement('div') together with jQuery is faster:

$(document.createElement('div'), {
    text: 'Div text',
    'class': 'className'
}).appendTo('#parentDiv');

Download file inside WebView

webView.setDownloadListener(new DownloadListener()
        {
            @Override
            public void onDownloadStart(String url, String userAgent,
                                        String contentDisposition, String mimeType,
                                        long contentLength) {
                DownloadManager.Request request = new DownloadManager.Request(
                        Uri.parse(url));
                request.setMimeType(mimeType);
                String cookies = CookieManager.getInstance().getCookie(url);
                request.addRequestHeader("cookie", cookies);
                request.addRequestHeader("User-Agent", userAgent);
                request.setDescription("Downloading File...");
                request.setTitle(URLUtil.guessFileName(url, contentDisposition, mimeType));
                request.allowScanningByMediaScanner();
                request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
                request.setDestinationInExternalPublicDir(
                        Environment.DIRECTORY_DOWNLOADS, URLUtil.guessFileName(
                                url, contentDisposition, mimeType));
                DownloadManager dm = (DownloadManager) getSystemService(DOWNLOAD_SERVICE);
                dm.enqueue(request);
                Toast.makeText(getApplicationContext(), "Downloading File", Toast.LENGTH_LONG).show();
            }});

Installing ADB on macOS

Option 3 - Using MacPorts

Analoguously to the two options (homebrew / manual) posted by @brismuth, here's the MacPorts way:

  1. Install the Android SDK:

    sudo port install android
    
  2. Run the SDK manager:

    sh /opt/local/share/java/android-sdk-macosx/tools/android
    
  3. As @brismuth suggested, uncheck everything but Android SDK Platform-tools (optional)

  4. Install the packages, accepting licenses. Close the SDK Manager.

  5. Add platform-tools to your path; in MacPorts, they're in /opt/local/share/java/android-sdk-macosx/platform-tools. E.g., for bash:

    echo 'export PATH=$PATH:/opt/local/share/java/android-sdk-macosx/platform-tools' >> ~/.bash_profile
    
  6. Refresh your bash profile (or restart your terminal/shell):

    source ~/.bash_profile
    
  7. Start using adb:

    adb devices
    

Automatic login script for a website on windows machine?

The code below does just that. The below is a working example to log into a game. I made a similar file to log in into Yahoo and a kurzweilai.net forum.

Just copy the login form from any webpage's source code. Add value= "your user name" and value = "your password". Normally the -input- elements in the source code do not have the value attribute, and sometime, you will see something like that: value=""

Save the file as a html on a local machine double click it, or make a bat/cmd file to launch and close them as required.

    <!doctype html>
    <!-- saved from url=(0014)about:internet -->

    <html>
    <title>Ikariam Autologin</title>
    </head>
    <body>
    <form id="loginForm" name="loginForm" method="post"    action="http://s666.en.ikariam.com/index.php?action=loginAvatar&function=login">
    <select name="uni_url" id="logServer" class="validate[required]">
    <option  class=""  value="s666.en.ikariam.com" fbUrl=""  cookieName=""  >
            Test_en
    </option>
    </select>
    <input id="loginName" name="name" type="text" value="PlayersName" class="" />
    <input id="loginPassword" name="password" type="password" value="examplepassword" class="" />
    <input type="hidden" id="loginKid" name="kid" value=""/>
                        </form>
  <script>document.loginForm.submit();</script>       
  </body></html>

Note that -script- is just -script-. I found there is no need to specify that is is JavaScript. It works anyway. I also found out that a bare-bones version that contains just two input filds: userName and password also work. But I left a hidded input field etc. just in case. Yahoo mail has a lot of hidden fields. Some are to do with password encryption, and it counts login attempts.

Security warnings and other staff, like Mark of the Web to make it work smoothly in IE are explained here:

http://happy-snail.webs.com/autologinintogames.htm

Generate random number between two numbers in JavaScript

Example

Return a random number between 1 and 10:

Math.floor((Math.random() * 10) + 1);

The result could be: 3

Try yourself: here

--

or using lodash / undescore:

_.random(min, max)

Docs: - lodash - undescore

Hide element by class in pure Javascript

document.getElementsByClassName returns an HTMLCollection(an array-like object) of all elements matching the class name. The style property is defined for Element not for HTMLCollection. You should access the first element using the bracket(subscript) notation.

document.getElementsByClassName('appBanner')[0].style.visibility = 'hidden';

Updated jsFiddle

To change the style rules of all elements matching the class, using the Selectors API:

[].forEach.call(document.querySelectorAll('.appBanner'), function (el) {
  el.style.visibility = 'hidden';
});

If for...of is available:

for (let el of document.querySelectorAll('.appBanner')) el.style.visibility = 'hidden';

Pushing to Git returning Error Code 403 fatal: HTTP request failed

Edit .git/config file under your repo directory

Find url= entry under section [remote "origin"]

Change it from url=https://github.com/rootux/ms-Dropdown.git to https://[email protected]/rootux/ms-Dropdown.git

where USERNAME is your github user name

How can I run a PHP script inside a HTML file?

Yes, you can run PHP in an HTML page.

I have successfully executed PHP code in my HTML files for many years. (For the curious, this is because I have over 8,000 static HTML files created by me and others over the last 20 years and I didn't want to lose search engine ranking by changing them and, more importantly, I have too many other things to work on).

I am not an expert -- below is what I've tried and what works for me. Please don't ask me to explain it.

Everything below involves adding a line or two to your .htaccess file.

Here is what one host ( http://simolyhosting.net ) support did for me in 2008 -- but it no longer works for me now.

AddHandler application/x-httpd-php5 .html .htm
AddType application/x-httpd-php5 .htm .html

That solution appears to be deprecated now, though it might work for you.

Here's what's working for me now:

AddType application/x-httpd-lsphp .htm .html

(This page has PHP code that executes properly with the above solution -- http://mykindred.com/bumstead/steeplehistory.htm )


Below are other solutions I found -- they are NOT MINE:


https://forums.cpanel.net/threads/cant-execute-php-in-html-since-ea4-upgrade.569531

I'm seeing this across many servers I've recently upgraded to EA4. Using cPanel Apache handlers or adding this directly in to .htaccess (same as cPanel does through gui add handlers):

AddHandler application/x-httpd-php5 .html

Sep 9, 2016

AddHandler application/x-httpd-ea-php56 .html

https://help.1and1.com/hosting-c37630/scripts-and-programming-languages-c85099/php-c37728/parsing-php-code-within-html-pages-a602364.html

Open a text editor such as wordpad, notepad, nano, etc. and add the following line:

AddHandler x-mapp-php5 .html .htm

If you want to use PHP 5.4 instead of PHP 5.2 then use the following line instead:

AddHandler x-mapp-php6 .html .htm

https://www.godaddy.com/community/Developer-Cloud-Portal/Running-php-in-html-files/td-p/2776

To run HTML using FastCGI/PHP, try adding this code to the .htaccess file for the directory the script is in:

Options +ExecCGI
AddHandler fcgid-script .html
FCGIWrapper /usr/local/cpanel/cgi-sys/php5 .html

You can add additional lines for other file extensions if needed.

calling another method from the main method in java

If you want to use do() in your main method there are 2 choices because one is static but other (do()) not

  1. Create new instance and invoke do() like new Foo().do();
  2. make static do() method

Have a look at this sun tutorial

How can I render HTML from another file in a React component?

You can use the dangerouslySetInnerHTML property to inject arbitrary HTML:

_x000D_
_x000D_
// Assume from another require()'ed module:_x000D_
var html = '<h1>Hello, world!</h1>'_x000D_
_x000D_
var MyComponent = React.createClass({_x000D_
  render: function() {_x000D_
    return React.createElement("h1", {dangerouslySetInnerHTML: {__html: html}})_x000D_
  }_x000D_
})_x000D_
_x000D_
ReactDOM.render(React.createElement(MyComponent), document.getElementById('app'))
_x000D_
<script src="https://fb.me/react-0.14.3.min.js"></script>_x000D_
<script src="https://fb.me/react-dom-0.14.3.min.js"></script>_x000D_
<div id="app"></div>
_x000D_
_x000D_
_x000D_

You could even componentize this template behavior (untested):

class TemplateComponent extends React.Component {
  constructor(props) {
    super(props)
    this.html = require(props.template)
  }

  render() {
    return <div dangerouslySetInnerHTML={{__html: this.html}}/>
  }

}

TemplateComponent.propTypes = {
  template: React.PropTypes.string.isRequired
}

// use like
<TemplateComponent template='./template.html'/>

And with this, template.html (in the same directory) looks something like (again, untested):

// ./template.html
module.exports = '<h1>Hello, world!</h1>'

Using msbuild to execute a File System Publish Profile

FYI: I had the same issue with Visual Studio 2015. After many of hours trying, I can now do msbuild myproject.csproj /p:DeployOnBuild=true /p:PublishProfile=myprofile.

I had to edit my .csproj file to get it working. It contained a line like this:

<Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v10.0\WebApplications\Microsoft.WebApplication.targets" 
  Condition="false" />

I changed this line as follows:

<Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v14.0\WebApplications\Microsoft.WebApplication.targets" />

(I changed 10.0 to 14.0, not sure whether this was necessary. But I definitely had to remove the condition part.)

Correct way to focus an element in Selenium WebDriver using Java

C# extension method code, focus element, enter text, call change().

public static void EnterText(this IWebDriver driver, IWebElement element, string textToEnter)
    {
        var js = (IJavaScriptExecutor)driver;
        js.ExecuteScript("arguments[0].focus();", element);
        js.ExecuteScript("arguments[0].setAttribute('value', arguments[1])", element, textToEnter);
        js.ExecuteScript("$(arguments[0]).change();", element);
    }

Called by:

driver.EnterText(element, text);

HTML5 Video Autoplay not working correctly

Working solution October 2018, for videos including audio channel

 $(document).ready(function() {
     $('video').prop('muted',true).play()
 });

Have a look at another of mine, more in-depth answer: https://stackoverflow.com/a/57723549/3049675

What Language is Used To Develop Using Unity

Some of the core differences between C# and Javascript script syntax in Unity.

http://unity3d.com/learn/tutorials/modules/beginner/scripting/c-sharp-vs-javascript-syntax

but keep in mind C# is the best one to develop in unity

word-wrap break-word does not work in this example

Work-Break has nothing to do with inline-block.

Make sure you specify width and notice if there are any overriding attributes in parent nodes. Make sure there is not white-space: nowrap.

see this codepen

_x000D_
_x000D_
<html>

<head>
</head>

<body>
  <style scoped>
    .parent {
      width: 100vw;
    }

    p {
      border: 1px dashed black;
      padding: 1em;
      font-size: calc(0.6vw + 0.6em);
      direction: ltr;
      width: 30vw;
      margin:auto;
      text-align:justify;
      word-break: break-word;
      white-space: pre-line;
      overflow-wrap: break-word;
      -ms-word-break: break-word;
      word-break: break-word;
      -ms-hyphens: auto;
      -moz-hyphens: auto;
      -webkit-hyphens: auto;
      hyphens: auto;
    }


    }
  </style>
  <div class="parent">

    <p>
      Note: Mind that, as for now, break-word is not part of the standard specification for webkit; therefore, you might be interested in employing the break-all instead. This alternative value provides a undoubtedly drastic solution; however, it conforms to
      the standard.

    </p>

  </div>

</body>

</html>
_x000D_
_x000D_
_x000D_

How to center the text in a JLabel?

myLabel.setHorizontalAlignment(SwingConstants.CENTER);
myLabel.setVerticalAlignment(SwingConstants.CENTER);

If you cannot reconstruct the label for some reason, this is how you edit these properties of a pre-existent JLabel.

Change Volley timeout duration

Just to contribute with my approach. As already answered, RetryPolicy is the way to go. But if you need a policy different the than default for all your requests, you can set it in a base Request class, so you don't need to set the policy for all the instances of your requests.

Something like this:

public class BaseRequest<T> extends Request<T> {

    public BaseRequest(int method, String url, Response.ErrorListener listener) {
        super(method, url, listener);
        setRetryPolicy(getMyOwnDefaultRetryPolicy());
    }
}

In my case I have a GsonRequest which extends from this BaseRequest, so I don't run the risk of forgetting to set the policy for an specific request and you can still override it if some specific request requires to.

Count all occurrences of a string in lots of files with grep

This works for multiple occurrences per line:

grep -o string * | wc -l

Javascript / Chrome - How to copy an object from the webkit inspector as code

Using "Store as a Global Variable" works, but it only gets the final instance of the object, and not the moment the object is being logged (since you're likely wanting to compare changes to the object as they happen). To get the object at its exact point in time of being modified, I use this...

function logObject(object) {
    console.info(JSON.stringify(object).replace(/,/g, ",\n"));
}

Call it like so...

logObject(puzzle);

You may want to remove the .replace(/./g, ",\n") regex if your data happens to have comma's in it.

Regex to get the words after matching string

Here's a quick Perl script to get what you need. It needs some whitespace chomping.

#!/bin/perl

$sample = <<END;
Subject:
  Security ID:        S-1-5-21-3368353891-1012177287-890106238-22451
  Account Name:       ChamaraKer
  Account Domain:     JIC
  Logon ID:       0x1fffb

Object:
  Object Server:  Security
  Object Type:    File
  Object Name:    D:\\ApacheTomcat\\apache-tomcat-6.0.36\\logs\\localhost.2013- 07-01.log
  Handle ID:  0x11dc
END

my @sample_lines = split /\n/, $sample;
my $path;

foreach my $line (@sample_lines) {
  ($path) = $line =~ m/Object Name:([^s]+)/g;
  if($path) {
    print $path . "\n";
  }
}

Delete multiple objects in django

You can delete any QuerySet you'd like. For example, to delete all blog posts with some Post model

Post.objects.all().delete()

and to delete any Post with a future publication date

Post.objects.filter(pub_date__gt=datetime.now()).delete()

You do, however, need to come up with a way to narrow down your QuerySet. If you just want a view to delete a particular object, look into the delete generic view.

EDIT:

Sorry for the misunderstanding. I think the answer is somewhere between. To implement your own, combine ModelForms and generic views. Otherwise, look into 3rd party apps that provide similar functionality. In a related question, the recommendation was django-filter.

HAX kernel module is not installed

First you need to turn on virtualization on your machine. To do that, restart your machine. Press F2. Goto BIOS. Make Virtualization Enabled. Press F10. Start windows. Now, goto Extras folder of Android installation folder and find intel-haxm-android.exe. Run it. Start Android Studio. Now, it should allow you to run your program using emulator.

Spring Boot REST service exception handling

Solution with dispatcherServlet.setThrowExceptionIfNoHandlerFound(true); and @EnableWebMvc @ControllerAdvice worked for me with Spring Boot 1.3.1, while was not working on 1.2.7

How do I validate a date string format in python?

I think the full validate function should look like this:

from datetime import datetime

def validate(date_text):
    try:
        if date_text != datetime.strptime(date_text, "%Y-%m-%d").strftime('%Y-%m-%d'):
            raise ValueError
        return True
    except ValueError:
        return False

Executing just

datetime.strptime(date_text, "%Y-%m-%d") 

is not enough because strptime method doesn't check that month and day of the month are zero-padded decimal numbers. For example

datetime.strptime("2016-5-3", '%Y-%m-%d')

will be executed without errors.

Importing Excel spreadsheet data into another Excel spreadsheet containing VBA

Data can be pulled into an excel from another excel through Workbook method or External reference or through Data Import facility.

If you want to read or even if you want to update another excel workbook, these methods can be used. We may not depend only on VBA for this.

For more info on these techniques, please click here to refer the article

Running interactive commands in Paramiko

ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(server_IP,22,username, password)


stdin, stdout, stderr = ssh.exec_command('/Users/lteue/Downloads/uecontrol-CXC_173_6456-R32A01/uecontrol.sh -host localhost ')
alldata = ""
while not stdout.channel.exit_status_ready():
   solo_line = ""        
   # Print stdout data when available
   if stdout.channel.recv_ready():
      # Retrieve the first 1024 bytes
      solo_line = stdout.channel.recv(1024) 
      alldata += solo_line
   if(cmp(solo_line,'uec> ') ==0 ):    #Change Conditionals to your code here  
     if num_of_input == 0 :
      data_buffer = ""    
      for cmd in commandList :
       #print cmd
       stdin.channel.send(cmd)        # send input commmand 1
      num_of_input += 1
     if num_of_input == 1 :
      stdin.channel.send('q \n')      # send input commmand 2 , in my code is exit the interactive session, the connect will close.
      num_of_input += 1 
print alldata
ssh.close()              

Why the stdout.read() will hang if use dierectly without checking stdout.channel.recv_ready(): in while stdout.channel.exit_status_ready():

For my case ,after run command on remote server , the session is waiting for user input , after input 'q' ,it will close the connection . But before inputting 'q' , the stdout.read() will waiting for EOF,seems this methord does not works if buffer is larger .

  • I tried stdout.read(1) in while , it works
    I tried stdout.readline() in while , it works also.
    stdin, stdout, stderr = ssh.exec_command('/Users/lteue/Downloads/uecontrol')
    stdout.read() will hang

keyCode values for numeric keypad?

******************* Don't use KEYCODE !!!! ******************

The problem with keyCode is to avoid the combined keys with the numbers on top of keyboard, we must add a check on the key "Shift" and "Alt" to avoid special characters such as e @ & " { } ...

A simplest solution is to convert e.key to a number and check if the conversion gives NaN!

let key = Number(e.key)
if (isNaN(key) || e.key === null || e.key === ' ') {
  console.log("is not numeric")
}
else {
  console.log("is numeric")
}

Be careful if e.key is null or a space, it gives 0 !

Number(5)         // => 5
Number('5')       // => 5
Number(null)      // => 0 
Number(' ')       // => 0
Number('chars')   // => NaN
Number(undefined) // => NaN

Why when I transfer a file through SFTP, it takes longer than FTP?

I'm the author of HPN-SSH and I was asked by a commenter here to weigh in. I'd like to start with a couple of background items. First off, it's important to keep in mind that SSHv2 is a multiplexed protocol - multiple channels over a single TCP connection. As such, the SSH channels are essentially unaware of the underlying flow control algorithm used by TCP. This means that SSHv2 has to implement its own flow control algorithm. The most common implementation basically reimplements sliding windows. The means that you have the SSH sliding window riding on top of the TCP sliding window. The end results is that the effective size of the receive buffer is the minimum of the receive buffers of the two sliding windows. Stock OpenSSH has a maximum receive buffer size of 2MB but this really ends up being closer to ~1.2MB. Most modern OSes have a buffer that can grow (using auto-tuning receive buffers) up to an effective size of 4MB. Why does this matter? If the receive buffer size is less than the bandwidth delay product (BDP) then you will never be able to fully fill the pipe regardless of how fast your system is.

This is complicated by the fact that SFTP adds another layer of flow control onto of the TCP and SSH flow controls. SFTP uses a concept of outstanding messages. Each message may be a command, a result of a command, or bulk data flow. The outstanding messages may be up to a specific datagram size. So you end up with what you might as well think of as yet another receive buffer. The size of this receive buffer is datagram size * maximum outstanding messages (both of which may be set on the command line). The default is 32k * 64 (2MB). So when using SFTP you have to make sure that the TCP receive buffer, the SSH receive buffer, and the SFTP receive buffer are all of sufficient size (without being too large or you can have over buffering problems in interactive sessions).

HPN-SSH directly addresses the SSH buffer problem by having a maximum buffer size of around 16MB. More importantly, the buffer dynamically grows to the proper size by polling the proc entry for the TCP connection's buffer size (basically poking a hole between layers 3 and 4). This avoids overbuffering in almost all situations. In SFTP we raise the maximum number of outstanding requests to 256. At least we should be doing that - it looks like that change didn't propagate as expected to the 6.3 patch set (though it is in 6.2. I'll fix that soon). There isn't a 6.4 version because 6.3 patches cleanly against 6.4 (which is a 1 line security fix from 6.3). You can get the patch set from sourceforge.

I know this sounds odd but right sizing the buffers was the single most important change in terms of performance. In spite of what many people think the encryption is not the real source of poor performance in most cases. You can prove this to yourself by transferring data to sources that are increasingly far away (in terms of RTT). You'll notice that the longer the RTT the lower the throughput. That clearly indicates that this is an RTT dependent performance problem.

Anyway, with this change I started seeing improvements of up to 2 orders of magnitude. If you understand TCP you'll understand why this made such a difference. It's not about the size of the datagram or the number of packets or anything like that. It's entire because in order to make efficient use of the network path you must have a receive buffer equal to the amount of data that can be in transit between the two hosts. This also means that you may not see any improvement whatsoever if the path isn't sufficiently fast and long enough. If the BDP is less than 1.2MB HPN-SSH may be of no value to you.

The parallelized AES-CTR cipher is a performance boost on systems with multiple cores if you need to have full encryption end to end. Usually I suggest people (or have control over both the server and client) to use the NONE cipher switch (encrypted authentication, bulk data passed in clear) as most data isn't all that sensitive. However, this only works in non-interactive sessions like SCP. It doesn't work in SFTP.

There are some other performance improvements as well but nothing as important as the right sizing of the buffers and the encryption work. When I get some free time I'll probably pipeline the HMAC process (currently the biggest drag on performance) and do some more minor optimization work.

So if HPN-SSH is so awesome why hasn't OpenSSH adopted it? That's a long story and people who know the OpenBSD team probably already know the answer. I understand many of their reasons - it's a big patch which would require additional work on their end (and they are a small team), they don't care as much about performance as security (though there is no security implications to HPN-SSH), etc etc etc. However, even though OpenSSH doesn't use HPN-SSH Facebook does. So do Google, Yahoo, Apple, most ever large research data center, NASA, NOAA, the government, the military, and most financial institutions. It's pretty well vetted at this point.

If anyone has any questions feel free to ask but I may not be keeping up to date on this forum. You can always send me mail via the HPN-SSH email address (google it).

How to return part of string before a certain character?

And note that first argument of subString is 0 based while second is one based.

Example:

String str= "0123456";
String sbstr= str.substring(0,5);

Output will be sbstr= 01234 and not sbstr = 012345

Cannot edit in read-only editor VS Code

I received the same error like @jgritten. Just like the comment before me by @jgritten, I 'unstaged' and reopened vscode and the files. Now I 'staged' it again. The error "Cannot edit in read-only editor" didnt come.

Hope this reassures anyone who might have similar error after staging the file using git in vscode.

Android Push Notifications: Icon not displaying in notification, white square shown instead

I found a link where we can generate our own white icon,

try this link to generate white icon of your launcher icon.

Open this Link and upload your ic_launcher or notification icon

How to use PowerShell select-string to find more than one pattern in a file?

To search for multiple matches in each file, we can sequence several Select-String calls:

Get-ChildItem C:\Logs |
  where { $_ | Select-String -Pattern 'VendorEnquiry' } |
  where { $_ | Select-String -Pattern 'Failed' } |
  ...

At each step, files that do not contain the current pattern will be filtered out, ensuring that the final list of files contains all of the search terms.

Rather than writing out each Select-String call manually, we can simplify this with a filter to match multiple patterns:

filter MultiSelect-String( [string[]]$Patterns ) {
  # Check the current item against all patterns.
  foreach( $Pattern in $Patterns ) {
    # If one of the patterns does not match, skip the item.
    $matched = @($_ | Select-String -Pattern $Pattern)
    if( -not $matched ) {
      return
    }
  }

  # If all patterns matched, pass the item through.
  $_
}

Get-ChildItem C:\Logs | MultiSelect-String 'VendorEnquiry','Failed',...


Now, to satisfy the "Logtime about 11:30 am" part of the example would require finding the log time corresponding to each failure entry. How to do this is highly dependent on the actual structure of the files, but testing for "about" is relatively simple:

function AboutTime( [DateTime]$time, [DateTime]$target, [TimeSpan]$epsilon ) {
  $time -le ($target + $epsilon) -and $time -ge ($target - $epsilon)
}

PS> $epsilon = [TimeSpan]::FromMinutes(5)
PS> $target = [DateTime]'11:30am'
PS> AboutTime '11:00am' $target $epsilon
False
PS> AboutTime '11:28am' $target $epsilon
True
PS> AboutTime '11:35am' $target $epsilon
True

Angularjs - Pass argument to directive

Insert the var msg in the click event with scope.$apply to make the changes to the confirm, based on your controller changes to the variables shown in ng-confirm-click therein.

<button type="button" class="btn" ng-confirm-click="You are about to send {{quantity}} of {{thing}} selected? Confirm with OK" confirmed-click="youraction(id)" aria-describedby="passwordHelpBlock">Send</button>




app.directive('ngConfirmClick', [
  function() {
    return {
      link: function(scope, element, attr) {
        var clickAction = attr.confirmedClick;
        element.on('click', function(event) {
          var msg = attr.ngConfirmClick || "Are you sure? Click OK to confirm.";
          if (window.confirm(msg)) {
            scope.$apply(clickAction)
          }
        });
      }
    };
  }
])

Convert hexadecimal string (hex) to a binary string

BigInteger.toString(radix) will do what you want. Just pass in a radix of 2.

static String hexToBin(String s) {
  return new BigInteger(s, 16).toString(2);
}

Catch an exception thrown by an async void method

Its also important to note that you will lose the chronological stack trace of the exception if you you have a void return type on an async method. I would recommend returning Task as follows. Going to make debugging a whole lot easier.

public async Task DoFoo()
    {
        try
        {
            return await Foo();
        }
        catch (ProtocolException ex)
        {
            /* Exception with chronological stack trace */     
        }
    }

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

If the content is just a very simple html, the simplest way is to remove the iframe with javascript

HTML code:

<div class="iframe">
    <iframe src="./mypage.html" frameborder="0" onload="removeIframe(this);"></iframe>
</div>

Javascript code:

function removeIframe(obj) {
    var iframeDocument = obj.contentDocument || obj.contentWindow.document;
    var mycontent = iframeDocument.getElementsByTagName("body")[0].innerHTML;
    obj.remove();
    document.getElementsByClassName("iframe")[0].innerHTML = mycontent;
}

Lombok is not generating getter and setter

When starting with a fresh eclipse installation you, in fact, need to "install" Lombok before being able to use it.

  1. Go where you Lombok jar is (e.g. (e.g. you can find in ~/.m2/repository/org/projectlombok/lombok/1.16.10/lombok-1.16.10.jar), run it (Example: java -jar lombok-1.16.10.jar). A window should appear, browse to your eclipse.exe location.
  2. Click on install.
  3. Launch Eclipse, update project configuration on all projects and voila.

How to find Port number of IP address?

DNS server usually have a standard of ports used. But if it's different, you could try nmap and do a port scan like so:

> nmap 127.0.0.1

Saving lists to txt file

@Jon's answer is great and will get you where you need to go. So why is your code printing out what it is. The answer: You're not writing out the contents of your list, but the String representation of your list itself, by an implicit call to Lists.verbList.ToString(). Object.ToString() defines the default behavior you're seeing here.

sqlplus error on select from external table: ORA-29913: error in executing ODCIEXTTABLEOPEN callout

Keep in mind that it's the user that is running the oracle database that must have write permissions to the /defaultdir directory, not the user logged into oracle. Typically you're running the database as the user "Oracle". It's not the same user (necessarily) that you created the external table with.

Check your directory permissions, too.

How to create a custom scrollbar on a div (Facebook style)

This link should get you started. Long story short, a div that has been styled to look like a scrollbar is used to catch click-and-drag events. Wired up to these events are methods that scroll the contents of another div which is set to an arbitrary height and typically has a css rule of overflow:scroll (there are variants on the css rules but you get the idea).

I'm all about the learning experience -- but after you've learned how it works, I recommend using a library (of which there are many) to do it. It's one of those "don't reinvent" things...

iOS (iPhone, iPad, iPodTouch) view real-time console log terminal

As an alternative, you can use an on-screen logging tool like ticker-log to view logs without having (convenient) access to the console.

Disable Copy or Paste action for text box?

You might also need to provide your user with an alert showing that those functions are disabled for the text input fields. This will work

_x000D_
_x000D_
    function showError(){_x000D_
     alert('you are not allowed to cut,copy or paste here');_x000D_
    }_x000D_
    _x000D_
    $('.form-control').bind("cut copy paste",function(e) {_x000D_
     e.preventDefault();_x000D_
    });
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<textarea class="form-control"  oncopy="showError()" onpaste="showError()"></textarea>
_x000D_
_x000D_
_x000D_

.keyCode vs. .which

If you are staying in vanilla Javascript, please note keyCode is now deprecated and will be dropped:

This feature has been removed from the Web standards. Though some browsers may still support it, it is in the process of being dropped. Avoid using it and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any tim

https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode

Instead use either: .key or .code depending on what behavior you want: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/code https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key

Both are implemented on modern browsers.

How can I break from a try/catch block without throwing an exception in Java

Various ways:

  • return
  • break or continue when in a loop
  • break to label when in a labeled statement (see @aioobe's example)
  • break when in a switch statement.

...

  • System.exit() ... though that's probably not what you mean.

In my opinion, "break to label" is the most natural (least contorted) way to do this if you just want to get out of a try/catch. But it could be confusing to novice Java programmers who have never encountered that Java construct.

But while labels are obscure, in my opinion wrapping the code in a do ... while (false) so that you can use a break is a worse idea. This will confuse non-novices as well as novices. It is better for novices (and non-novices!) to learn about labeled statements.


By the way, return works in the case where you need to break out of a finally. But you should avoid doing a return in a finally block because the semantics are a bit confusing, and liable to give the reader a headache.

Convert special characters to HTML in Javascript

Here are a couple methods I use without the need of Jquery:

You can encode every character in your string:

function encode(e){return e.replace(/[^]/g,function(e){return"&#"+e.charCodeAt(0)+";"})}

Or just target the main safe encoding characters to worry about (&, inebreaks, <, >, " and ') like:

_x000D_
_x000D_
function encode(r){_x000D_
return r.replace(/[\x26\x0A\<>'"]/g,function(r){return"&#"+r.charCodeAt(0)+";"})_x000D_
}_x000D_
_x000D_
test.value=encode('How to encode\nonly html tags &<>\'" nice & fast!');_x000D_
_x000D_
/*************_x000D_
* \x26 is &ampersand (it has to be first),_x000D_
* \x0A is newline,_x000D_
*************/
_x000D_
<textarea id=test rows="9" cols="55">www.WHAK.com</textarea>
_x000D_
_x000D_
_x000D_

How to add a "sleep" or "wait" to my Lua Script?

function wait(time)
    local duration = os.time() + time
    while os.time() < duration do end
end

This is probably one of the easiest ways to add a wait/sleep function to your script

Getting "error": "unsupported_grant_type" when trying to get a JWT by calling an OWIN OAuth secured Web Api via Postman

The response is a bit late - but in case anyone has the issue in the future...

From the screenshot above - it seems that you are adding the url data (username, password, grant_type) to the header and not to the body element.

Clicking on the body tab, and then select "x-www-form-urlencoded" radio button, there should be a key-value list below that where you can enter the request data

How to solve "sign_and_send_pubkey: signing failed: agent refused operation"?

To this error:

# git pull
sign_and_send_pubkey: signing failed: agent refused operation
[email protected]: Permission denied (publickey).    
fatal: Could not read from remote repository.

Please make sure you have the correct access rights and the repository exists.

Verify or add again the public key in Github account > profile > ssh.

I solved like this:

# chmod 400 ~/.ssh/id_rsa

# ls  ~/.ssh/id_rsa -ls  
4 -r--------. 1 reinaldo reinaldo 1679 Jul 26  2017 /home/reinaldo/.ssh/id_rsa

# git pull                                 
remote: Counting objects: 35, done.
remote: Compressing objects: 100% (19/19), done.
remote: Total 35 (delta 9), reused 34 (delta 9), pack-reused 0
Unpacking objects: 100% (35/35), done.

Thank you.

How do I copy the contents of one stream to another?

Easy and safe - make new stream from original source:

    MemoryStream source = new MemoryStream(byteArray);
    MemoryStream copy = new MemoryStream(byteArray);

how to convert milliseconds to date format in android?

This is the easiest way using Kotlin

private const val DATE_FORMAT = "dd/MM/yy hh:mm"

fun millisToDate(millis: Long) : String {
    return SimpleDateFormat(DATE_FORMAT, Locale.US).format(Date(millis))
}

Capturing console output from a .NET application (C#)

This can be quite easily achieved using the ProcessStartInfo.RedirectStandardOutput property. A full sample is contained in the linked MSDN documentation; the only caveat is that you may have to redirect the standard error stream as well to see all output of your application.

Process compiler = new Process();
compiler.StartInfo.FileName = "csc.exe";
compiler.StartInfo.Arguments = "/r:System.dll /out:sample.exe stdstr.cs";
compiler.StartInfo.UseShellExecute = false;
compiler.StartInfo.RedirectStandardOutput = true;
compiler.Start();    

Console.WriteLine(compiler.StandardOutput.ReadToEnd());

compiler.WaitForExit();

Javascript Iframe innerHTML

You can use the contentDocument or contentWindow property for that purpose. Here is the sample code.

function gethtml() {
  const x = document.getElementById("myframe")
  const y = x.contentWindow || x.contentDocument
  const z = y.document ? y.document : y
  alert(z.body.innerHTML)
}

here, myframe is the id of your iframe. Note: You can't extract the content out of an iframe from a src outside you domain.

Printing newlines with print() in R

An alternative to cat() is writeLines():

> writeLines("File not supplied.\nUsage: ./program F=filename")
File not supplied.
Usage: ./program F=filename
>

An advantage is that you don't have to remember to append a "\n" to the string passed to cat() to get a newline after your message. E.g. compare the above to the same cat() output:

> cat("File not supplied.\nUsage: ./program F=filename")
File not supplied.
Usage: ./program F=filename>

and

> cat("File not supplied.\nUsage: ./program F=filename","\n")
File not supplied.
Usage: ./program F=filename
>

The reason print() doesn't do what you want is that print() shows you a version of the object from the R level - in this case it is a character string. You need to use other functions like cat() and writeLines() to display the string. I say "a version" because precision may be reduced in printed numerics, and the printed object may be augmented with extra information, for example.

Viewing local storage contents on IE

In IE11, you can see local storage in console on dev tools:

  1. Show dev tools (press F12)
  2. Click "Console" or press Ctrl+2
  3. Type localStorage and press Enter

Also, if you need to clear the localStorage, type localStorage.clear() on console.

What is the difference between Swing and AWT?

Swing vs AWT. Basically AWT came first and is a set of heavyweight UI components (meaning they are wrappers for operating system objects) whereas Swing built on top of AWT with a richer set of lightweight components.

Any serious Java UI work is done in Swing not AWT, which was primarily used for applets.

Fast way to concatenate strings in nodeJS/JavaScript

The question is already answered, however when I first saw it I thought of NodeJS Buffer. But it is way slower than the +, so it is likely that nothing can be faster than + in string concetanation.

Tested with the following code:

function a(){
    var s = "hello";
    var p = "world";
    s = s + p;
    return s;
}

function b(){
    var s = new Buffer("hello");
    var p = new Buffer("world");
    s = Buffer.concat([s,p]);
    return s;
}

var times = 100000;

var t1 = new Date();
for( var i = 0; i < times; i++){
    a();
}

var t2 = new Date();
console.log("Normal took: " + (t2-t1) + " ms.");
for ( var i = 0; i < times; i++){
    b();
}

var t3 = new Date();

console.log("Buffer took: " + (t3-t2) + " ms.");

Output:

Normal took: 4 ms.
Buffer took: 458 ms.

Error parsing XHTML: The content of elements must consist of well-formed character data or markup

I solved this converting the JSP from XHTML to HTML, doing this in the begining:

<%@page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>
...

how to rename an index in a cluster?

Another different way to achieve the renaming or change the mappings for an index is to reindex using logstash. Here is a sample of the logstash 2.1 configuration:

input {
  elasticsearch {
   hosts => ["es01.example.com", "es02.example.com"]
   index => "old-index-name"
   size => 500
   scroll => "5m"
  }
}
filter {

 mutate {
  remove_field => [ "@version" ]
 }

 date {
   "match" => [ "custom_timestamp", "MM/dd/YYYY HH:mm:ss" ]
   target => "@timestamp"
 }

}
output {
 elasticsearch {
   hosts => ["es01.example.com", "es02.example.com" ]
   manage_template => false
   index => "new-index-name"
 }
}

Get file name from a file location in Java

From Apache Commons IO FileNameUtils

String fileName = FilenameUtils.getName(stringNameWithPath);

Python - List of unique dictionaries

Here's a reasonably compact solution, though I suspect not particularly efficient (to put it mildly):

>>> ds = [{'id':1,'name':'john', 'age':34},
...       {'id':1,'name':'john', 'age':34},
...       {'id':2,'name':'hanna', 'age':30}
...       ]
>>> map(dict, set(tuple(sorted(d.items())) for d in ds))
[{'age': 30, 'id': 2, 'name': 'hanna'}, {'age': 34, 'id': 1, 'name': 'john'}]

How to hide 'Back' button on navigation bar on iPhone?

Don't forget that we have the slide to back gesture now. You probably want to remove this as well. Don't forget to enable it back again if necessary.

if ([self.navigationItem respondsToSelector:@selector(hidesBackButton)]) {
    self.navigationItem.hidesBackButton = YES;
}

if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {
    self.navigationController.interactivePopGestureRecognizer.enabled = NO;
}

Should import statements always be at the top of a module?

I wouldn't worry about the efficiency of loading the module up front too much. The memory taken up by the module won't be very big (assuming it's modular enough) and the startup cost will be negligible.

In most cases you want to load the modules at the top of the source file. For somebody reading your code, it makes it much easier to tell what function or object came from what module.

One good reason to import a module elsewhere in the code is if it's used in a debugging statement.

For example:

do_something_with_x(x)

I could debug this with:

from pprint import pprint
pprint(x)
do_something_with_x(x)

Of course, the other reason to import modules elsewhere in the code is if you need to dynamically import them. This is because you pretty much don't have any choice.

I wouldn't worry about the efficiency of loading the module up front too much. The memory taken up by the module won't be very big (assuming it's modular enough) and the startup cost will be negligible.

how to output every line in a file python

Did you try

for line in open("masters", "r").readlines(): print line

?

readline() 

only reads "a line", on the other hand

readlines()

reads whole lines and gives you a list of all lines.

jwt check if token expired

This is the answer if someone want to know

if (Date.now() >= exp * 1000) {
  return false;
}

disable a hyperlink using jQuery

The pointer-events CSS property is a little lacking when it comes to support (caniuse.com), but it's very succinct:

.my-link { pointer-events: none; } 

How to reset settings in Visual Studio Code?

Go to File -> preferences -> settings.

On the right panel you will see all customized user settings so you can remove the ones you want to reset. On doing so the default settings mentioned in left pane will become active instantly.

top align in html table?

<TABLE COLS="3" border="0" cellspacing="0" cellpadding="0">
    <TR style="vertical-align:top">
        <TD>
            <!-- The log text-box -->
            <div style="height:800px; width:240px; border:1px solid #ccc; font:16px/26px Georgia, Garamond, Serif; overflow:auto;">
                Log:
            </div>
        </TD>
        <TD>
            <!-- The 2nd column -->
        </TD>
        <TD>
            <!-- The 3rd column -->
        </TD>
    </TR>
</TABLE>

How to calculate distance from Wifi router using Signal Strength?

the simple answer to your question would be Triangulation. Which is essentially the concept in all GPS devices, I would give this article a read to learn more about how Google goes about doing this: http://www.computerworld.com/s/article/9127462/FAQ_How_Google_Latitude_locates_you_?taxonomyId=15&pageNumber=2.

From my understanding, they use a service similar to Skyhook, which is a location software that determines your location based on your wifi/cellphone signals. In order to achieve their accuracy, these services have large servers of databases that store location information on these cell towers and wifi access points - they actually survey metropolitan areas to keep it up to date. In order for you to achieve something similar, I would assume you'd have to use a service like Skyhook - you can use their SDK ( http://www.skyhookwireless.com/location-technology/ ).

However, if you want to do something internal (like using your own routers' locations) - then you'd likely have to create an algorithm that mimics Triangulation. You'll have to find a way to get the signal_strength and mac_address of the device and use that information along with the locations of your routers to come up with the location. You can probably get the information about devices hooked up to your routers by doing something similar to this ( http://www.makeuseof.com/tag/check-stealing-wifi/ ).

Check if multiple strings exist in another string

You should be careful if the strings in a or str gets longer. The straightforward solutions take O(S*(A^2)), where S is the length of str and A is the sum of the lenghts of all strings in a. For a faster solution, look at Aho-Corasick algorithm for string matching, which runs in linear time O(S+A).

Why am I getting "Received fatal alert: protocol_version" or "peer not authenticated" from Maven Central?

In June 2018, in an effort to raise security and comply with modern standards, the insecure TLS 1.0 & 1.1 protocols will no longer be supported for SSL connections to Central. This should only affect users of Java 6 (and Java 7) that are also using https to access central, which by our metrics is less than .2% of users.

For more details and workarounds, see the blog and faq here: https://blog.sonatype.com/enhancing-ssl-security-and-http/2-support-for-central

Calling a Fragment method from a parent Activity

From fragment to activty:

((YourActivityClassName)getActivity()).yourPublicMethod();

From activity to fragment:

FragmentManager fm = getSupportFragmentManager();

//if you added fragment via layout xml
YourFragmentClass fragment = 
(YourFragmentClass)fm.findFragmentById(R.id.your_fragment_id);
fragment.yourPublicMethod();

If you added fragment via code and used a tag string when you added your fragment, use findFragmentByTag instead:

YourFragmentClass fragment = (YourFragmentClass)fm.findFragmentByTag("yourTag");

Bubble Sort Homework

def bubble_sort(li):
    l = len(li)
    tmp = None
    sorted_l = sorted(li)
    while (li != sorted_l):
        for ele in range(0,l-1):
            if li[ele] > li[ele+1]:
                tmp = li[ele+1]
                li[ele+1] = li [ele]
                li[ele] = tmp
    return li

Xcode 6 Bug: Unknown class in Interface Builder file

I had this problem after I added a new target, then created a new class using the 'New File' dialog but accidentally failed to check the new target as well as the original target in the creation dialog, so the object was only added to my original target. The solution was to delete the source files (remove reference only) then add them back using 'Add Files', this time checking both targets.

Turning a Comma Separated string into individual rows

Check this

 SELECT A.OtherID,  
     Split.a.value('.', 'VARCHAR(100)') AS Data  
 FROM  
 (
     SELECT OtherID,  
         CAST ('<M>' + REPLACE(Data, ',', '</M><M>') + '</M>' AS XML) AS Data  
     FROM  Table1
 ) AS A CROSS APPLY Data.nodes ('/M') AS Split(a); 

Can promises have multiple arguments to onFulfilled?

The fulfillment value of a promise parallels the return value of a function and the rejection reason of a promise parallels the thrown exception of a function. Functions cannot return multiple values so promises must not have more than 1 fulfillment value.

Failed to auto-configure a DataSource: 'spring.datasource.url' is not specified

your dependency based on data is trying to find their respective entities which one has not been created, comments the dependencies based on data and runs the app again.

<!-- <dependency> -->
        <!-- <groupId>org.springframework.boot</groupId> -->
        <!-- <artifactId>spring-boot-starter-data-jpa</artifactId> -->
        <!-- </dependency> -->

Delete all rows in a table based on another table

delete
    table1
from 
    t2
where
    table1.ID=t2.ID

Works on mssql

How to deal with page breaks when printing a large HTML table

I checked many solutions and anyone wasn't working good.

So I tried a small trick and it works:

tfoot with style:position: fixed; bottom: 0px; is placed at the bottom of last page, but if footer is too high it is overlapped by content of table.

tfoot with only: display: table-footer-group; isn't overlapped, but is not on the bottom of last page...

Let's put two tfoot:

_x000D_
_x000D_
TFOOT.placer {_x000D_
  display: table-footer-group;_x000D_
  height: 130px;_x000D_
}_x000D_
_x000D_
TFOOT.contenter {_x000D_
  display: table-footer-group;_x000D_
  position: fixed;_x000D_
  bottom: 0px; _x000D_
  height: 130px;_x000D_
}
_x000D_
<TFOOT  class='placer'> _x000D_
  <TR>_x000D_
    <TD>_x000D_
      <!--  empty here_x000D_
-->_x000D_
    </TD>_x000D_
  </TR>_x000D_
</TFOOT> _x000D_
<TFOOT  class='contenter'> _x000D_
  <TR>_x000D_
    <TD>_x000D_
      your long text or high image here_x000D_
    </TD>_x000D_
  </TR>_x000D_
</TFOOT>
_x000D_
_x000D_
_x000D_

One reserves place on non-last pages, second puts in your accual footer.

Has been compiled by a more recent version of the Java Runtime (class file version 57.0)

how i solve it in Eclipse

  1. go to the properties of the project enter image description here

  2. go to Java compiler enter image description here

  3. change in the Compiler complicated level to java that my project work with (java 11 in my project) you can see that it your java that you work when the last message disappear

  4. Apply enter image description here

(How) can I count the items in an enum?

There's not really a good way to do this, usually you see an extra item in the enum, i.e.

enum foobar {foo, bar, baz, quz, FOOBAR_NR_ITEMS};

So then you can do:

int fuz[FOOBAR_NR_ITEMS];

Still not very nice though.

But of course you do realize that just the number of items in an enum is not safe, given e.g.

enum foobar {foo, bar = 5, baz, quz = 20};

the number of items would be 4, but the integer values of the enum values would be way out of the array index range. Using enum values for array indexing is not safe, you should consider other options.

edit: as requested, made the special entry stick out more.

Dynamically update values of a chartjs chart

You also can use destroy() function. Like this

 if( window.myBar!==undefined)
     window.myBar.destroy();
 var ctx = document.getElementById("canvas").getContext("2d");
 window.myBar = new Chart(ctx).Bar(barChartData, {
     responsive : true,
 });

Display an image with Python

Your first suggestion works for me

from IPython.display import display, Image
display(Image(filename='path/to/image.jpg'))

Flask at first run: Do not use the development server in a production environment

Unless you tell the development server that it's running in development mode, it will assume you're using it in production and warn you not to. The development server is not intended for use in production. It is not designed to be particularly efficient, stable, or secure.

Enable development mode by setting the FLASK_ENV environment variable to development.

$ export FLASK_APP=example
$ export FLASK_ENV=development
$ flask run

If you're running in PyCharm (or probably any other IDE) you can set environment variables in the run configuration.

Development mode enables the debugger and reloader by default. If you don't want these, pass --no-debugger or --no-reloader to the run command.


That warning is just a warning though, it's not an error preventing your app from running. If your app isn't working, there's something else wrong with your code.

WebSockets vs. Server-Sent events/EventSource

Here is a talk about the differences between web sockets and server sent events. Since Java EE 7 a WebSocket API is already part of the specification and it seems that server sent events will be released in the next version of the enterprise edition.

Add multiple items to a list

Another useful way is with Concat.
More information in the official documentation.

List<string> first = new List<string> { "One", "Two", "Three" };
List<string> second = new List<string>() { "Four", "Five" };
first.Concat(second);

The output will be.

One
Two
Three
Four
Five

And there is another similar answer.

Removing black dots from li and ul

Relatable post

Those pesky black dots you are referencing to are called bullets.

They are pretty simple to remove, just add this line to your css:

ul {
    list-style-type: none;
}

Hope this helps

Side-by-side list items as icons within a div (css)

give the LI float: left (or right)

They will all be in the same line until there will be no more room in the container (your case, a ul). (forgot): If you have a block element after the floating elements, he will also stick to them, unless you give him a clear:both, OR put an empty div before it with clear:both

Is it possible to write to the console in colour in .NET?

Yes. See this article. Here's an example from there:

Console.BackgroundColor = ConsoleColor.Blue;
Console.ForegroundColor = ConsoleColor.White;
Console.WriteLine("White on blue.");

enter image description here

package javax.mail and javax.mail.internet do not exist

Had the same issue. Obviously these .jars were included with Java <= v8.x out of the box, but are not anymore. Thus one has to separately download them and place them in the appropriate classpath as highlighted by several folks above. I understand that the new Java is modularized and thus potentially more light-weight (which is certainly a good thing, since the old setup was a monster). On the other hand this - as we can see - breaks lots of old build setups. Since the time to fix these isn't chargeable to Oracle I guess this made their decision easy...

jQuery limit to 2 decimal places

Here is a working example in both Javascript and jQuery:

http://jsfiddle.net/GuLYN/312/

//In jQuery
$("#calculate").click(function() {
    var num = parseFloat($("#textbox").val());
    var new_num = $("#textbox").val(num.toFixed(2));
});


// In javascript
document.getElementById('calculate').onclick = function() {
    var num = parseFloat(document.getElementById('textbox').value);
    var new_num = num.toFixed(2);
    document.getElementById('textbox').value = new_num;
};
?

Using Java to find substring of a bigger string using Regular Expression

String input = "FOO[BAR]";
String result = input.substring(input.indexOf("[")+1,input.lastIndexOf("]"));

This will return the value between first '[' and last ']'

Foo[Bar] => Bar

Foo[Bar[test]] => Bar[test]

Note: You should add error checking if the input string is not well formed.

Token based authentication in Web API without any user interface

ASP.Net Web API has Authorization Server build-in already. You can see it inside Startup.cs when you create a new ASP.Net Web Application with Web API template.

OAuthOptions = new OAuthAuthorizationServerOptions
{
    TokenEndpointPath = new PathString("/Token"),
    Provider = new ApplicationOAuthProvider(PublicClientId),
    AuthorizeEndpointPath = new PathString("/api/Account/ExternalLogin"),
    AccessTokenExpireTimeSpan = TimeSpan.FromDays(14),
    // In production mode set AllowInsecureHttp = false
    AllowInsecureHttp = true
};

All you have to do is to post URL encoded username and password inside query string.

/Token/userName=johndoe%40example.com&password=1234&grant_type=password

If you want to know more detail, you can watch User Registration and Login - Angular Front to Back with Web API by Deborah Kurata.

Swift: How to get substring from start to last index of character

I also build a simple String-extension for Swift 4:

extension String {
    func subStr(s: Int, l: Int) -> String { //s=start, l=lenth
        let r = Range(NSRange(location: s, length: l))!
        let fromIndex = self.index(self.startIndex, offsetBy: r.lowerBound)
        let toIndex = self.index(self.startIndex, offsetBy: r.upperBound)
        let indexRange = Range<String.Index>(uncheckedBounds: (lower: fromIndex, upper: toIndex))

        return String(self[indexRange])
     }
}

So you can easily call it like this:

"Hallo world".subStr(s: 1, l: 3) //prints --> "all"

MySQL/Writing file error (Errcode 28)

Use the perror command:

$ perror 28
OS error code  28:  No space left on device

Unless error codes are different on your system, your file system is full.

How to find the sum of an array of numbers

A "duplicate" question asked how to do this for a two-dimensional array, so this is a simple adaptation to answer that question. (The difference is only the six characters [2], 0, which finds the third item in each subarray and passes an initial value of zero):

_x000D_
_x000D_
const twoDimensionalArray = [_x000D_
  [10, 10, 1],_x000D_
  [10, 10, 2],_x000D_
  [10, 10, 3],_x000D_
];_x000D_
const sum = twoDimensionalArray.reduce( (partial_sum, a) => partial_sum + a[2], 0 ) ; _x000D_
console.log(sum); // 6
_x000D_
_x000D_
_x000D_

How do I use DateTime.TryParse with a Nullable<DateTime>?

Here is a slightly concised edition of what Jason suggested:

DateTime? d; DateTime dt;
d = DateTime.TryParse(DateTime.Now.ToString(), out dt)? dt : (DateTime?)null;

How to generate a random number in C++?

Here is a simple random generator with approx. equal probability of generating positive and negative values around 0:

  int getNextRandom(const size_t lim) 
  {
        int nextRand = rand() % lim;
        int nextSign = rand() % lim;
        if (nextSign < lim / 2)
            return -nextRand;
        return nextRand;
  }


   int main()
   {
        srand(time(NULL));
        int r = getNextRandom(100);
        cout << r << endl;
        return 0;
   }

Unfortunately Launcher3 has stopped working error in android studio?

I didn't found any particular answer to this question but i deleted the emulator and create a new one and increase the Ram size of the new emulator.Then the emulator works fine.

Set EditText cursor color

The only valid answer should be to change the theme of the activity: <item name="colorAccent">#000000</item> You should not use the android:textCursorDrawable to @null because this only concerns the cursor itself but not the pin below the cursor if you want to drag that cursor. The theming solution is the most serious one.

Python 3 - ValueError: not enough values to unpack (expected 3, got 2)

1. First should understand the error meaning

Error not enough values to unpack (expected 3, got 2) means:

a 2 part tuple, but assign to 3 values

and I have written demo code to show for you:


#!/usr/bin/python
# -*- coding: utf-8 -*-
# Function: Showing how to understand ValueError 'not enough values to unpack (expected 3, got 2)'
# Author: Crifan Li
# Update: 20191212

def notEnoughUnpack():
    """Showing how to understand python error `not enough values to unpack (expected 3, got 2)`"""
    # a dict, which single key's value is two part tuple
    valueIsTwoPartTupleDict = {
        "name1": ("lastname1", "email1"),
        "name2": ("lastname2", "email2"),
    }

    # Test case 1: got value from key
    gotLastname, gotEmail = valueIsTwoPartTupleDict["name1"] # OK
    print("gotLastname=%s, gotEmail=%s" % (gotLastname, gotEmail))
    # gotLastname, gotEmail, gotOtherSomeValue = valueIsTwoPartTupleDict["name1"] # -> ValueError not enough values to unpack (expected 3, got 2)

    # Test case 2: got from dict.items()
    for eachKey, eachValues in valueIsTwoPartTupleDict.items():
        print("eachKey=%s, eachValues=%s" % (eachKey, eachValues))
    # same as following:
    # Background knowledge: each of dict.items() return (key, values)
    # here above eachValues is a tuple of two parts
    for eachKey, (eachValuePart1, eachValuePart2) in valueIsTwoPartTupleDict.items():
        print("eachKey=%s, eachValuePart1=%s, eachValuePart2=%s" % (eachKey, eachValuePart1, eachValuePart2))
    # but following:
    for eachKey, (eachValuePart1, eachValuePart2, eachValuePart3) in valueIsTwoPartTupleDict.items(): # will -> ValueError not enough values to unpack (expected 3, got 2)
        pass

if __name__ == "__main__":
    notEnoughUnpack()

using VSCode debug effect:

notEnoughUnpack CrifanLi

2. For your code

for name, email, lastname in unpaidMembers.items():

but error ValueError: not enough values to unpack (expected 3, got 2)

means each item(a tuple value) in unpaidMembers, only have 1 parts:email, which corresponding above code

    unpaidMembers[name] = email

so should change code to:

for name, email in unpaidMembers.items():

to avoid error.

But obviously you expect extra lastname, so should change your above code to

    unpaidMembers[name] = (email, lastname)

and better change to better syntax:

for name, (email, lastname) in unpaidMembers.items():

then everything is OK and clear.

Regular expression to extract numbers from a string

^\s*(\w+)\s*\(\s*(\d+)\D+(\d+)\D+\)\s*$

should work. After the match, backreference 1 will contain the month, backreference 2 will contain the first number and backreference 3 the second number.

Explanation:

^     # start of string
\s*   # optional whitespace
(\w+) # one or more alphanumeric characters, capture the match
\s*   # optional whitespace
\(    # a (
\s*   # optional whitespace
(\d+) # a number, capture the match
\D+   # one or more non-digits
(\d+) # a number, capture the match
\D+   # one or more non-digits
\)    # a )
\s*   # optional whitespace
$     # end of string

There can be only one auto column

Note also that "key" does not necessarily mean primary key. Something like this will work:

CREATE TABLE book (
    isbn             BIGINT NOT NULL PRIMARY KEY,
    id               INT    NOT NULL AUTO_INCREMENT,
    accepted_terms   BIT(1) NOT NULL,
    accepted_privacy BIT(1) NOT NULL,
    INDEX(id)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

This is a contrived example and probably not the best idea, but it can be very useful in certain cases.

printing a value of a variable in postgresql

You can raise a notice in Postgres as follows:

raise notice 'Value: %', deletedContactId;

Read here

in iPhone App How to detect the screen resolution of the device

For iOS 8 we can just use this [UIScreen mainScreen].nativeBounds , like that:

- (NSInteger)resolutionX
{
    return CGRectGetWidth([UIScreen mainScreen].nativeBounds);
}

- (NSInteger)resolutionY
{
    return CGRectGetHeight([UIScreen mainScreen].nativeBounds);
}

Centering a background image, using CSS

I think this is what is wanted:

body
{
    background-image:url('smiley.gif');
    background-repeat:no-repeat;
    background-attachment:fixed;
    background-position:center;
}