Programs & Examples On #Openvms

For questions that are specific to the OpenVMS (AKA VAX/VMS) operating system. If your question has nothing to do with OpenVMS APIs or OpenVMS-specific behavior then do not use this tag. This tag is appropriate for any software running on OpenVMS.

Playing .mp3 and .wav in Java?

Java FX has Media and MediaPlayer classes which will play mp3 files.

Example code:

String bip = "bip.mp3";
Media hit = new Media(new File(bip).toURI().toString());
MediaPlayer mediaPlayer = new MediaPlayer(hit);
mediaPlayer.play();

You will need the following import statements:

import java.io.File;
import javafx.scene.media.Media;
import javafx.scene.media.MediaPlayer;

Parse Error: Adjacent JSX elements must be wrapped in an enclosing tag

If you don't want to wrap it in another div as other answers have suggested, you can also wrap it in an array and it will work.

// Wrong!
return (  
   <Comp1 />
   <Comp2 />
)

It can be written as:

// Correct!
return (  
    [<Comp1 />,
    <Comp2 />]
)

Please note that the above will generate a warning: Warning: Each child in an array or iterator should have a unique "key" prop. Check the render method of 'YourComponent'.

This can be fixed by adding a key attribute to the components, if manually adding these add it like:

return (  
    [<Comp1 key="0" />,
    <Comp2 key="1" />]
)

Here is some more information on keys:Composition vs Inheritance

How to start anonymous thread class

Not exactly sure this is what you are asking but you can do something like:

new Thread() {
    public void run() {
        System.out.println("blah");
    }
}.start();

Notice the start() method at the end of the anonymous class. You create the thread object but you need to start it to actually get another running thread.

Better than creating an anonymous Thread class is to create an anonymous Runnable class:

new Thread(new Runnable() {
    public void run() {
        System.out.println("blah");
    }
}).start();

Instead overriding the run() method in the Thread you inject a target Runnable to be run by the new thread. This is a better pattern.

Initializing C# auto-properties

In the default constructor (and any non-default ones if you have any too of course):

public foo() {
    Bar = "bar";
}

This is no less performant that your original code I believe, since this is what happens behind the scenes anyway.

Vue template or render function not defined yet I am using neither?

If someone else keeps getting the same error. Just add one extra div in your component template.

As the documentation says:

Component template should contain exactly one root element

Check this simple example:

 import yourComponent from '{path to component}'
    export default {
        components: {
            yourComponent
        },
}

 // Child component
 <template>
     <div> This is the one! </div>
 </template>

Select values from XML field in SQL Server 2008

If you are able to wrap your XML in a root element - say then the following is your solution:

DECLARE @PersonsXml XML = '<persons><person><firstName>Jon</firstName><lastName>Johnson</lastName></person>
<person><firstName>Kathy</firstName><lastName>Carter</lastName></person>
<person><firstName>Bob</firstName><lastName>Burns</lastName></person></persons>'

SELECT  b.value('(./firstName/text())[1]','nvarchar(max)') as FirstName, b.value('(./lastName/text())[1]','nvarchar(max)') as LastName
FROM @PersonsXml.nodes('/persons/person') AS a(b)

enter image description here

Get class labels from Keras functional model

In addition to @Emilia Apostolova answer to get the ground truth labels, from

generator = train_datagen.flow_from_directory("train", batch_size=batch_size)

just call

y_true_labels = generator.classes

Visual studio - getting error "Metadata file 'XYZ' could not be found" after edit continue

Eventually what solved the issue was:

  1. Clean every project individually (Right click> Clean).
  2. Rebuild every project individually (Right click> Rebuild).
  3. Rebuild the startup project.

I guess for some reason, just cleaning the solution had a different effect than specifically cleaning every project individually.

Edit:
As per @maplemale comment, It seems that sometimes removing and re-adding each reference is also required.

Update 2019:
This question got a lot of traffic in the past, but it seems that since VS 2017 was released, it got much less attention.
So another suggestion would be - Update to a newer version of VS (>= 2017) and among other new features this issue will also be solved

Find the maximum value in a list of tuples in Python

Use max():

 
Using itemgetter():

In [53]: lis=[(101, 153), (255, 827), (361, 961)]

In [81]: from operator import itemgetter

In [82]: max(lis,key=itemgetter(1))[0]    #faster solution
Out[82]: 361

using lambda:

In [54]: max(lis,key=lambda item:item[1])
Out[54]: (361, 961)

In [55]: max(lis,key=lambda item:item[1])[0]
Out[55]: 361

timeit comparison:

In [30]: %timeit max(lis,key=itemgetter(1))
1000 loops, best of 3: 232 us per loop

In [31]: %timeit max(lis,key=lambda item:item[1])
1000 loops, best of 3: 556 us per loop

ConnectionTimeout versus SocketTimeout

A connection timeout is the maximum amount of time that the program is willing to wait to setup a connection to another process. You aren't getting or posting any application data at this point, just establishing the connection, itself.

A socket timeout is the timeout when waiting for individual packets. It's a common misconception that a socket timeout is the timeout to receive the full response. So if you have a socket timeout of 1 second, and a response comprised of 3 IP packets, where each response packet takes 0.9 seconds to arrive, for a total response time of 2.7 seconds, then there will be no timeout.

How to force an entire layout View refresh?

To clear a view extending ViewGroup, you just need to use the method removeAllViews()

Just like this (if you have a ViewGroup called myElement) :

myElement.removeAllViews()

How to Use -confirm in PowerShell

Write-Warning "This is only a test warning." -WarningAction Inquire

from: https://serverfault.com/a/1015583/584478

How to install JSTL? The absolute uri: http://java.sun.com/jstl/core cannot be resolved

org.apache.jasper.JasperException: The absolute uri: http://java.sun.com/jstl/core cannot be resolved in either web.xml or the jar files deployed with this application

That URI is for JSTL 1.0, but you're actually using JSTL 1.2 which uses URIs with an additional /jsp path (because JSTL, who invented EL expressions, was since version 1.1 integrated as part of JSP in order to share/reuse the EL logic in plain JSP too).

So, fix the taglib URI accordingly based on JSTL documentation:

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

Further you need to make absolutely sure that you do not throw multiple different versioned JSTL JAR files together into the runtime classpath. This is a pretty common mistake among Tomcat users. The problem with Tomcat is that it does not offer JSTL out the box and thus you have to manually install it. This is not necessary in normal Jakarta EE servers. See also What exactly is Java EE?

In your specific case, your pom.xml basically tells you that you have jstl-1.2.jar and standard-1.1.2.jar together. This is wrong. You're basically mixing JSTL 1.2 API+impl from Oracle with JSTL 1.1 impl from Apache. You should stick to only one JSTL implementation.

Installing JSTL on Tomcat 10+

In case you're already on Tomcat 10 or newer (the first Jakartified version, with jakarta.* package instead of javax.* package), use JSTL 2.0 via this sole dependency:

<dependency>
    <groupId>org.glassfish.web</groupId>
    <artifactId>jakarta.servlet.jsp.jstl</artifactId>
    <version>2.0.0</version>
</dependency>

Non-Maven users can achieve the same by dropping the following two physical files in /WEB-INF/lib folder of the web application project (do absolutely not drop standard*.jar or any loose .tld files in there! remove them if necessary).

Installing JSTL on Tomcat 9-

In case you're not on Tomcat 10 yet, but still on Tomcat 9 or older, use JSTL 1.2 via this sole dependency:

<dependency>
    <groupId>org.glassfish.web</groupId>
    <artifactId>jakarta.servlet.jsp.jstl</artifactId>
    <version>1.2.6</version>
</dependency>

Non-Maven users can achieve the same by dropping the following two physical files in /WEB-INF/lib folder of the web application project (do absolutely not drop standard*.jar or any loose .tld files in there! remove them if necessary).

Installing JSTL on normal JEE server

In case you're actually using a normal Jakarta EE server such as WildFly, Payara, etc instead of a barebones servletcontainer such as Tomcat, Jetty, etc, then you don't need to explicitly install JSTL at all. Normal Jakarta EE servers already provide JSTL out the box. In other words, you don't need to add JSTL to pom.xml nor to drop any JAR/TLD files in webapp. Solely the provided scoped Jakarta EE coordinate is sufficient:

<dependency>
    <groupId>jakarta.platform</groupId>
    <artifactId>jakarta.jakartaee-api</artifactId>
    <version><!-- 9.0.0, 8.0.0, etc depending on your server --></version>
    <scope>provided</scope>
</dependency>

Make sure web.xml version is right

Further you should also make sure that your web.xml is declared conform at least Servlet 2.4 and thus not as Servlet 2.3 or older. Otherwise EL expressions inside JSTL tags would in turn fail to work. Pick the highest version matching your target container and make sure that you don't have a <!DOCTYPE> anywhere in your web.xml. Here's a Servlet 5.0 (Tomcat 10) compatible example:

<?xml version="1.0" encoding="UTF-8"?>
<web-app 
    xmlns="https://jakarta.ee/xml/ns/jakartaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="https://jakarta.ee/xml/ns/jakartaee https://jakarta.ee/xml/ns/jakartaee/web-app_5_0.xsd"
    version="5.0">

    <!-- Config here. -->

</web-app>

And here's a Servlet 4.0 (Tomcat 9) compatible example:

<?xml version="1.0" encoding="UTF-8"?>
<web-app
    xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
    version="4.0">

    <!-- Config here. -->

</web-app>

See also:

Using generic std::function objects with member functions in one class

You can avoid std::bind doing this:

std::function<void(void)> f = [this]-> {Foo::doSomething();}

Alternative to google finance api

I'm way late, but check out Quandl. They have an API for stock prices and fundamentals.

Here's an example call, using Quandl-api download in csv

example:

https://www.quandl.com/api/v1/datasets/WIKI/AAPL.csv?column=4&sort_order=asc&collapse=quarterly&trim_start=2012-01-01&trim_end=2013-12-31

They support these languages. Their source data comes from Yahoo Finance, Google Finance, NSE, BSE, FSE, HKEX, LSE, SSE, TSE and more (see here).

Open two instances of a file in a single Visual Studio session

Luke's answer didn't work for me. The 'New Window' command was already listed in the customize settings, but not showing up in the .js tabs context menu, despite deleting the registry setting.

So I used:

Tools

Customize...

Keyboard...

Scroll down to select Window.NewWindow

And I pressed and assigned the shortcut keys, Ctrl + Shift + W.

That worked for me.

==== EDIT ====

Well, 'worked' was too strong. My keyboard shortcut does indeed open another tab on the same JavaScript file, but rather unhelpfully it does not render the contents; it is just an empty white window! You may have better luck.

MySQL JOIN ON vs USING?

Wikipedia has the following information about USING:

The USING construct is more than mere syntactic sugar, however, since the result set differs from the result set of the version with the explicit predicate. Specifically, any columns mentioned in the USING list will appear only once, with an unqualified name, rather than once for each table in the join. In the case above, there will be a single DepartmentID column and no employee.DepartmentID or department.DepartmentID.

Tables that it was talking about:

enter image description here

The Postgres documentation also defines them pretty well:

The ON clause is the most general kind of join condition: it takes a Boolean value expression of the same kind as is used in a WHERE clause. A pair of rows from T1 and T2 match if the ON expression evaluates to true.

The USING clause is a shorthand that allows you to take advantage of the specific situation where both sides of the join use the same name for the joining column(s). It takes a comma-separated list of the shared column names and forms a join condition that includes an equality comparison for each one. For example, joining T1 and T2 with USING (a, b) produces the join condition ON T1.a = T2.a AND T1.b = T2.b.

Furthermore, the output of JOIN USING suppresses redundant columns: there is no need to print both of the matched columns, since they must have equal values. While JOIN ON produces all columns from T1 followed by all columns from T2, JOIN USING produces one output column for each of the listed column pairs (in the listed order), followed by any remaining columns from T1, followed by any remaining columns from T2.

How does one get started with procedural generation?

Procedural generation is used heavily in the demoscene to create complex graphics in a small executable. Will Wright even said that he was inspired by the demoscene while making Spore. That may be your best place to start.

http://en.wikipedia.org/wiki/Demoscene

Convert floats to ints in Pandas?

Here's a simple function that will downcast floats into the smallest possible integer type that doesn't lose any information. For examples,

  • 100.0 can be converted from float to integer, but 99.9 can't (without losing information to rounding or truncation)

  • Additionally, 1.0 can be downcast all the way to int8 without losing information, but the smallest integer type for 100_000.0 is int32

Code examples:

import numpy as np
import pandas as pd

def float_to_int( s ):
    if ( s.astype(np.int64) == s ).all():
        return pd.to_numeric( s, downcast='integer' )
    else:
        return s

# small integers are downcast into 8-bit integers
float_to_int( np.array([1.0,2.0]) )
Out[1]:array([1, 2], dtype=int8)

# larger integers are downcast into larger integer types
float_to_int( np.array([100_000.,200_000.]) )
Out[2]: array([100000, 200000], dtype=int32)

# if there are values to the right of the decimal
# point, no conversion is made
float_to_int( np.array([1.1,2.2]) )
Out[3]: array([ 1.1,  2.2])

How to find the length of a string in R

nchar(YOURSTRING)

you may need to convert to a character vector first;

nchar(as.character(YOURSTRING))

Python: Open file in zip without temporarily extracting it

In theory, yes, it's just a matter of plugging things in. Zipfile can give you a file-like object for a file in a zip archive, and image.load will accept a file-like object. So something like this should work:

import zipfile
archive = zipfile.ZipFile('images.zip', 'r')
imgfile = archive.open('img_01.png')
try:
    image = pygame.image.load(imgfile, 'img_01.png')
finally:
    imgfile.close()

127 Return code from $?

Generally it means:

127 - command not found

but it can also mean that the command is found,
but a library that is required by the command is NOT found.

Using scanner.nextLine()

It's because when you enter a number then press Enter, input.nextInt() consumes only the number, not the "end of line". Primitive data types like int, double etc do not consume "end of line", therefore the "end of line" remains in buffer and When input.next() executes, it consumes the "end of line" from buffer from the first input. That's why, your String sentence = scanner.next() only consumes the "end of line" and does not wait to read from keyboard.

Tip: use scanner.nextLine() instead of scanner.next() because scanner.next() does not read white spaces from the keyboard. (Truncate the string after giving some space from keyboard, only show string before space.)

Open File in Another Directory (Python)

from pathlib import Path

data_folder = Path("source_data/text_files/")
file_to_open = data_folder / "raw_data.txt"

f = open(file_to_open)
print(f.read())

How to view UTF-8 Characters in VIM or Gvim

If Japanese people come here, please add the following lines to your ~/.vimrc

set encoding=utf-8
set fileencodings=iso-2022-jp,euc-jp,sjis,utf-8
set fileformats=unix,dos,mac

Use string in switch case in java

Evaluating String variables with a switch statement have been implemented in Java SE 7, and hence it only works in java 7. You can also have a look at how this new feature is implemented in JDK 7.

Checking for Undefined In React

I was face same problem ..... And I got solution by using typeof()

if (typeof(value) !== 'undefined' && value != null) {
         console.log('Not Undefined and Not Null')
  } else {
         console.log('Undefined or Null')
}

You must have to use typeof() to identified undefined

Rounded Corners Image in Flutter

You can use CircleAvatar Widget with radius:

CircleAvatar(
             radius: 50.0,
             backgroundImage: AssetImage("assets/img1.jpeg"),
            ),

JDBC ResultSet: I need a getDateTime, but there is only getDate and getTimeStamp

java.util.Date date;
Timestamp timestamp = resultSet.getTimestamp(i);
if (timestamp != null)
    date = new java.util.Date(timestamp.getTime()));

Then format it the way you like.

Stop Visual Studio from mixing line endings in files

With VS2010+ there is a plugin solution: Line Endings Unifier.

With the plugin installed you can right click files and folders in the solution explorer and invoke the menu item Unify Line Endings in this file

Configuration for this is available via

Tools -> Options -> Line Endings Unifier.

The default file extension list that is included is pretty narrow:

 .cpp; .c; .h; .hpp; .cs; .js; .vb; .txt;

Might want to use something like:

 .cpp; .c; .h; .hpp; .cs; .js; .vb; .txt; .scss; .coffee; .ts; .jsx; .markdown; .config

How to use ADB Shell when Multiple Devices are connected? Fails with "error: more than one device and emulator"

Running adb commands on all connected devices

Create a bash (adb+)

adb devices | while read line
do
if [ ! "$line" = "" ] && [ `echo $line | awk '{print $2}'` = "device" ]
then
    device=`echo $line | awk '{print $1}'`
    echo "$device $@ ..."
    adb -s $device $@
fi

done use it with

adb+ //+ command

Is JavaScript's "new" keyword considered harmful?

I agree with pez and some here.

It seems obvious to me that "new" is self descriptive object creation, where the YUI pattern Greg Dean describes is completely obscured.

The possibility someone could write var bar = foo; or var bar = baz(); where baz isn't an object creating method seems far more dangerous.

Manifest Merger failed with multiple errors in Android Studio

Put this at the end of your app module build.gradle:

configurations.all {
resolutionStrategy.eachDependency { DependencyResolveDetails details ->
    def requested = details.requested
    if (requested.group == 'com.android.support') {
        if (!requested.name.startsWith("multidex")) {
            details.useVersion '25.3.0'
        }
    }
}}

from this

How do you make a LinearLayout scrollable?

<ScrollView 
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:id="@+id/scroll" 
      android:layout_width="match_parent"
      android:layout_height="wrap_content">

      <LinearLayout 
            android:id="@+id/container"
            android:orientation="vertical" 
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
      </LinearLayout>

 </ScrollView>

Setting the height of a DIV dynamically

If I understand what you're asking, this should do the trick:

// the more standards compliant browsers (mozilla/netscape/opera/IE7) use 
// window.innerWidth and window.innerHeight

var windowHeight;

if (typeof window.innerWidth != 'undefined')
{
    windowHeight = window.innerHeight;
}
// IE6 in standards compliant mode (i.e. with a valid doctype as the first 
// line in the document)
else if (typeof document.documentElement != 'undefined'
        && typeof document.documentElement.clientWidth != 'undefined' 
        && document.documentElement.clientWidth != 0)
{
    windowHeight = document.documentElement.clientHeight;
}
// older versions of IE
else
{
    windowHeight = document.getElementsByTagName('body')[0].clientHeight;
}

document.getElementById("yourDiv").height = windowHeight - 300 + "px";

Creating a UITableView Programmatically

vc.m

#import "ViewController.h"

import "secondViewController.h"

 @interface ViewController ()
 {

NSArray *cityArray;
NSArray *citySubTitleArray;
NSArray *cityImage;
NSInteger selectindexpath;

}
@end

 @implementation ViewController

 - (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.

cityArray = [[NSArray 
alloc]initWithObjects:@"Coimbatore",@"Salem",@"Chennai",nil];

citySubTitleArray = [[NSArray alloc]initWithObjects:@"1",@"2",@"3", nil];
cityImage = [[NSArray alloc]initWithObjects:@"12-300x272.png"
 , @"380267_70d232fc33b44d4ebe7b42bbe63ee9be.png",@"apple-logo_318
 -40184.png", nil];

 }


 #pragma mark - UITableView Data Source

 - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
 {
return 1;

 }

 - (NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection 
 :(NSInteger)section
  {
return cityImage.count;
 }

- (UITableViewCell *)tableView:(UITableView *)tableView 
cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellId = @"city";

UITableViewCell *cell =
 [tableView dequeueReusableCellWithIdentifier:cellId];

if (cell == nil)
{
    cell = [[UITableViewCell 
  alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellId];
}

cell.textLabel.text = [cityArray objectAtIndex:indexPath.row];
cell.detailTextLabel.text = [citySubTitleArray objectAtIndex:indexPath.row];
cell.imageView.image = [UIImage imageNamed:
 [cityImage objectAtIndex:indexPath.row]];




 //    NSData *data = [[NSData alloc]initWithContentsOfURL:
 [NSURL URLWithString:@""]];

 //    cell.imageView.image = [UIImage imageWithData:data];

return cell;
}

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath
:  (NSIndexPath *)indexPath
 {
 NSLog(@"---- %@",[cityArray objectAtIndex:indexPath.row]);
 NSLog(@"----- %@",[cityImage objectAtIndex:indexPath.row]);
 selectindexpath=indexPath.row;
 [self performSegueWithIdentifier:@"second" sender:self];
  }

  #pragma mark - Navigation

 // In a storyboard-based application, you will often want to do a little p
 - (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
    {
 // Get the new view controller using [segue destinationViewController].
 // Pass the selected object to the new view controller.
 if ([segue.identifier isEqualToString:@"second"])
 {
    secondViewController *object=segue.destinationViewController;
    object.cityName=[cityArray objectAtIndex:selectindexpath];
    object.cityImage=[cityImage objectAtIndex:selectindexpath];
       }
 }


- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
 }

 @end

vc.m

 #import <UIKit/UIKit.h>

 @interface ViewController : UIViewController<UITableViewDataSource
  , UITableViewDelegate>
 @property (strong, nonatomic) IBOutlet UITableView *cityLabelList;

@end

sv.m

 #import <UIKit/UIKit.h>

@interface secondViewController : UIViewController
@property(strong, nonatomic) NSString *cityName;
 @property(strong,nonatomic)NSString *cityImage;
@end

sv.h

#import "secondViewController.h"

 @interface secondViewController ()

 @property (strong, nonatomic) IBOutlet UILabel *lbl_desc;
 @property (strong, nonatomic) IBOutlet UIImageView *img_city;
    @end

 @implementation secondViewController

 - (void)viewDidLoad {
 [super viewDidLoad];
// Do any additional setup after loading the view.
self.title=self.cityName;


if ([self.cityName isEqualToString:@"Coimbatore"])
{


    self.lbl_desc.text=@"Coimbatore city";
    self.img_city.image=[UIImage imageNamed:
    [NSString stringWithFormat:@"%@",self.cityImage]];
}
 else if ([self.cityName isEqualToString:@"Chennai"])
 {

    self.lbl_desc.text= @"Chennai City Gangstar";
    self.img_city.image=[UIImage imageNamed:
   [NSString stringWithFormat:@"%@",self.cityImage]];

   }
  else
   {


    self.lbl_desc.text= @"selam City";
    self.img_city.image=[UIImage imageNamed:
   [NSString stringWithFormat:@"%@",self.cityImage]];

   }
 }

- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}

Get only specific attributes with from Laravel Collection

$users = Users::get();

$subset = $users->map(function ($user) {
    return array_only(user, ['id', 'name', 'email']);
});

How do I convert 2018-04-10T04:00:00.000Z string to DateTime?

Update: Using DateTimeFormat, introduced in java 8:

The idea is to define two formats: one for the input format, and one for the output format. Parse with the input formatter, then format with the output formatter.

Your input format looks quite standard, except the trailing Z. Anyway, let's deal with this: "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'". The trailing 'Z' is the interesting part. Usually there's time zone data here, like -0700. So the pattern would be ...Z, i.e. without apostrophes.

The output format is way more simple: "dd-MM-yyyy". Mind the small y -s.

Here is the example code:

DateTimeFormatter inputFormatter = DateTimeFormatter.ofPattern("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", Locale.ENGLISH);
DateTimeFormatter outputFormatter = DateTimeFormatter.ofPattern("dd-MM-yyy", Locale.ENGLISH);
LocalDate date = LocalDate.parse("2018-04-10T04:00:00.000Z", inputFormatter);
String formattedDate = outputFormatter.format(date);
System.out.println(formattedDate); // prints 10-04-2018

Original answer - with old API SimpleDateFormat

SimpleDateFormat inputFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
SimpleDateFormat outputFormat = new SimpleDateFormat("dd-MM-yyyy");
Date date = inputFormat.parse("2018-04-10T04:00:00.000Z");
String formattedDate = outputFormat.format(date);
System.out.println(formattedDate); // prints 10-04-2018

How to count the number of rows in excel with data?

Found this approach on another site. It works with the new larger sizes of Excel and doesn't require you to hardcode the max number of rows and columns.

iLastRow = Cells(Rows.Count, "a").End(xlUp).Row
iLastCol = Cells(i, Columns.Count).End(xlToLeft).Column

Thanks to mudraker in Melborne, Australia

Overlay normal curve to histogram in R

You just need to find the right multiplier, which can be easily calculated from the hist object.

myhist <- hist(mtcars$mpg)
multiplier <- myhist$counts / myhist$density
mydensity <- density(mtcars$mpg)
mydensity$y <- mydensity$y * multiplier[1]

plot(myhist)
lines(mydensity)

enter image description here

A more complete version, with a normal density and lines at each standard deviation away from the mean (including the mean):

myhist <- hist(mtcars$mpg)
multiplier <- myhist$counts / myhist$density
mydensity <- density(mtcars$mpg)
mydensity$y <- mydensity$y * multiplier[1]

plot(myhist)
lines(mydensity)

myx <- seq(min(mtcars$mpg), max(mtcars$mpg), length.out= 100)
mymean <- mean(mtcars$mpg)
mysd <- sd(mtcars$mpg)

normal <- dnorm(x = myx, mean = mymean, sd = mysd)
lines(myx, normal * multiplier[1], col = "blue", lwd = 2)

sd_x <- seq(mymean - 3 * mysd, mymean + 3 * mysd, by = mysd)
sd_y <- dnorm(x = sd_x, mean = mymean, sd = mysd) * multiplier[1]

segments(x0 = sd_x, y0= 0, x1 = sd_x, y1 = sd_y, col = "firebrick4", lwd = 2)

Characters allowed in GET parameter

I did a test using the Chrome address bar and a $QUERY_STRING in bash, and observed the following:

~!@$%^&*()-_=+[{]}\|;:',./? and grave (backtick) are passed through as plaintext.

, ", < and > are converted to %20, %22, %3C and %3E respectively.

# is ignored, since it is used by ye olde anchor.

Personally, I'd say bite the bullet and encode with base64 :)

How to install PyQt4 on Windows using pip?

Earlier PyQt .exe installers were available directly from the website download page. Now with the release of PyQt4.12 , installers have been deprecated. You can make the libraries work somehow by compiling them but that would mean going to great lengths of trouble.

Otherwise you can use the previous distributions to solve your purpose. The .exe windows installers can be downloaded from :

https://sourceforge.net/projects/pyqt/files/PyQt4/PyQt-4.11.4/

How to run a PowerShell script without displaying a window?

ps1 hidden from the Task Scheduler and shortcut too

    mshta vbscript:Execute("CreateObject(""WScript.Shell"").Run ""powershell -ExecutionPolicy Bypass & 'C:\PATH\NAME.ps1'"", 0:close")

How to comment and uncomment blocks of code in the Office VBA Editor

Steps to comment / uncommented

Press alt + f11/ Developer tab visual basic editor view tab - toolbar - edit - comments.

System.currentTimeMillis vs System.nanoTime

Update by Arkadiy: I've observed more correct behavior of System.currentTimeMillis() on Windows 7 in Oracle Java 8. The time was returned with 1 millisecond precision. The source code in OpenJDK has not changed, so I do not know what causes the better behavior.


David Holmes of Sun posted a blog article a couple years ago that has a very detailed look at the Java timing APIs (in particular System.currentTimeMillis() and System.nanoTime()), when you would want to use which, and how they work internally.

Inside the Hotspot VM: Clocks, Timers and Scheduling Events - Part I - Windows

One very interesting aspect of the timer used by Java on Windows for APIs that have a timed wait parameter is that the resolution of the timer can change depending on what other API calls may have been made - system wide (not just in the particular process). He shows an example where using Thread.sleep() will cause this resolution change.

How does the bitwise complement operator (~ tilde) work?

The bit-wise operator is a unary operator which works on sign and magnitude method as per my experience and knowledge.

For example ~2 would result in -3.

This is because the bit-wise operator would first represent the number in sign and magnitude which is 0000 0010 (8 bit operator) where the MSB is the sign bit.

Then later it would take the negative number of 2 which is -2.

-2 is represented as 1000 0010 (8 bit operator) in sign and magnitude.

Later it adds a 1 to the LSB (1000 0010 + 1) which gives you 1000 0011.

Which is -3.

ERROR:'keytool' is not recognized as an internal or external command, operable program or batch file

This is due to path not set where keytool.exe present.

Open command prompt in windows machine, traverse where you would like to run keytool cmd and set path where keytool.exe present

Step 1 : Open cmd promt and run "cd C:\Program Files\Java\jdk1.8.0_131\jre\lib\security"

Step 2 : Run below cmd to set path using "set PATH=C:\Program Files\Java\jdk1.8.0_131\bin"

Step 3 : Run keytool cmd, now it will be able to recognize.

jQuery get the location of an element relative to window

Initially, Grab the .offset position of the element and calculate its relative position with respect to window

Refer :
1. offset
2. scroll
3. scrollTop

You can give it a try at this fiddle

Following few lines of code explains how this can be solved

when .scroll event is performed, we calculate the relative position of the element with respect to window object

$(window).scroll(function () {
    console.log(eTop - $(window).scrollTop());
});

when scroll is performed in browser, we call the above event handler function

code snippet


_x000D_
_x000D_
function log(txt) {_x000D_
  $("#log").html("location : <b>" + txt + "</b> px")_x000D_
}_x000D_
_x000D_
$(function() {_x000D_
  var eTop = $('#element').offset().top; //get the offset top of the element_x000D_
  log(eTop - $(window).scrollTop()); //position of the ele w.r.t window_x000D_
_x000D_
  $(window).scroll(function() { //when window is scrolled_x000D_
    log(eTop - $(window).scrollTop());_x000D_
  });_x000D_
});
_x000D_
#element {_x000D_
  margin: 140px;_x000D_
  text-align: center;_x000D_
  padding: 5px;_x000D_
  width: 200px;_x000D_
  height: 200px;_x000D_
  border: 1px solid #0099f9;_x000D_
  border-radius: 3px;_x000D_
  background: #444;_x000D_
  color: #0099d9;_x000D_
  opacity: 0.6;_x000D_
}_x000D_
#log {_x000D_
  position: fixed;_x000D_
  top: 40px;_x000D_
  left: 40px;_x000D_
  color: #333;_x000D_
}_x000D_
#scroll {_x000D_
  position: fixed;_x000D_
  bottom: 10px;_x000D_
  right: 10px;_x000D_
  border: 1px solid #000;_x000D_
  border-radius: 2px;_x000D_
  padding: 5px;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<div id="log"></div>_x000D_
_x000D_
<div id="element">Hello_x000D_
  <hr>World</div>_x000D_
<div id="scroll">Scroll Down</div>
_x000D_
_x000D_
_x000D_

How do I see active SQL Server connections?

I threw this together so that you could do some querying on the results

Declare @dbName varchar(150)
set @dbName = '[YOURDATABASENAME]'

--Total machine connections
--SELECT  COUNT(dbid) as TotalConnections FROM sys.sysprocesses WHERE dbid > 0

--Available connections
DECLARE @SPWHO1 TABLE (DBName VARCHAR(1000) NULL, NoOfAvailableConnections VARCHAR(1000) NULL, LoginName VARCHAR(1000) NULL)
INSERT INTO @SPWHO1 
    SELECT db_name(dbid), count(dbid), loginame FROM sys.sysprocesses WHERE dbid > 0 GROUP BY dbid, loginame
SELECT * FROM @SPWHO1 WHERE DBName = @dbName

--Running connections
DECLARE @SPWHO2 TABLE (SPID VARCHAR(1000), [Status] VARCHAR(1000) NULL, [Login] VARCHAR(1000) NULL, HostName VARCHAR(1000) NULL, BlkBy VARCHAR(1000) NULL, DBName VARCHAR(1000) NULL, Command VARCHAR(1000) NULL, CPUTime VARCHAR(1000) NULL, DiskIO VARCHAR(1000) NULL, LastBatch VARCHAR(1000) NULL, ProgramName VARCHAR(1000) NULL, SPID2 VARCHAR(1000) NULL, Request VARCHAR(1000) NULL)
INSERT INTO @SPWHO2 
    EXEC sp_who2 'Active'
SELECT * FROM @SPWHO2 WHERE DBName = @dbName

How to search in array of object in mongodb

The right way is:

db.users.find({awards: {$elemMatch: {award:'National Medal', year:1975}}})

$elemMatch allows you to match more than one component within the same array element.

Without $elemMatch mongo will look for users with National Medal in some year and some award in 1975s, but not for users with National Medal in 1975.

See MongoDB $elemMatch Documentation for more info. See Read Operations Documentation for more information about querying documents with arrays.

Increment variable value by 1 ( shell programming)

There are more than one way to increment a variable in bash, but what you tried is not correct.

You can use for example arithmetic expansion:

i=$((i+1))

or only:

((i=i+1))

or:

((i+=1))

or even:

((i++))

Or you can use let:

let "i=i+1"

or only:

let "i+=1"

or even:

let "i++"

See also: http://tldp.org/LDP/abs/html/dblparens.html.

How to increase apache timeout directive in .htaccess?

if you have long processing server side code, I don't think it does fall into 404 as you said ("it goes to a webpage is not found error page")

Browser should report request timeout error.

You may do 2 things:

Based on CGI/Server side engine increase timeout there

PHP : http://www.php.net/manual/en/info.configuration.php#ini.max-execution-time - default is 30 seconds

In php.ini:

max_execution_time 60

Increase apache timeout - default is 300 (in version 2.4 it is 60).

In your httpd.conf (in server config or vhost config)

TimeOut 600

Note that first setting allows your PHP script to run longer, it will not interferre with network timeout.

Second setting modify maximum amount of time the server will wait for certain events before failing a request

Sorry, I'm not sure if you are using PHP as server side processing, but if you provide more info I will be more accurate.

MySQL error - #1932 - Table 'phpmyadmin.pma user config' doesn't exist in engine

Had the same problem in Ubuntu 14 using XAMPP. Here's what I did which worked..

  1. Stop mysql if its running in xampp
  2. vi /opt/lamp/phpmyadmin/config.inc.php (use sudo if you are not the su)
  3. replace

    $cfg['Servers'][1]['relation'] = 'pma__relation';
    $cfg['Servers'][1]['userconfig'] = 'pma__userconfig';
    $cfg['Servers'][1]['table_info'] = 'pma__table_info';
    ...
    

    to

    $cfg['Servers'][1]['pma__relation'] = 'pma__relation';
    $cfg['Servers'][1]['pma__userconfig'] = 'pma__userconfig';
    $cfg['Servers'][1]['pma__table_info'] = 'pma__table_info';
    ...
    

    basically add pma__ prefix to the left side similar to the right.

  4. Run mysql and access localhost/phpmyadmin and click on a db to check if it works.

Hope this helps.

How to concat string + i?

For versions prior to R2014a...

One easy non-loop approach would be to use genvarname to create a cell array of strings:

>> N = 5;
>> f = genvarname(repmat({'f'}, 1, N), 'f')

f = 

    'f1'    'f2'    'f3'    'f4'    'f5'

For newer versions...

The function genvarname has been deprecated, so matlab.lang.makeUniqueStrings can be used instead in the following way to get the same output:

>> N = 5;
>> f = strrep(matlab.lang.makeUniqueStrings(repmat({'f'}, 1, N), 'f'), '_', '')

 f =
   1×5 cell array

     'f1'    'f2'    'f3'    'f4'    'f5'

Installing Java on OS X 10.9 (Mavericks)

This error happens because the plist file of IntelliJ IDEA requires Java version 1.6*. To solve this problem, replace the 1.6* with 1.8*.

<key>JVMOptions</key>
<dict>
    <key>ClassPath</key>
      ...

    <key>JVMVersion</key>
    <string>1.8*</string>

    <key>MainClass</key>
    <string>com.intellij.idea.Main</string>
    <key>Properties</key>
<dict>

How to check if a particular service is running on Ubuntu

run

ps -ef | grep name-related-to-process

above command will give all the details like pid, start time about the process.

like if you want all java realted process give java or if you have name of process place the name

Can I clear cell contents without changing styling?

you can use ClearContents. ex,

Range("X").Cells.ClearContents

How to use CSS to surround a number with a circle?

I am surprised nobody used flex which is easier to understand, so I put my version of answer here:

  1. To create a circle, make sure width equals height
  2. To adapt to font-size of number in the circle, use em rather than px
  3. To center the number in the circle, use flex with justify-content: center; align-items: center;
  4. if the number grows (>1000 for example), increase the width and height at same time

Here is an example:

_x000D_
_x000D_
.circled-number {
  color: #666;
  border: 2px solid #666;
  border-radius: 50%;
  font-size: 1rem;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 2em; 
  height: 2em;
}

.circled-number--big {
  color: #666;
  border: 2px solid #666;
  border-radius: 50%;
  font-size: 1rem;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 4em; 
  height: 4em;
}
_x000D_
<div class="circled-number">
  30
</div>

<div class="circled-number--big">
  3000000
</div>
_x000D_
_x000D_
_x000D_

How do I find the data directory for a SQL Server instance?

You can find default Data and Log locations for the current SQL Server instance by using the following T-SQL:

DECLARE @defaultDataLocation nvarchar(4000)
DECLARE @defaultLogLocation nvarchar(4000)

EXEC master.dbo.xp_instance_regread
    N'HKEY_LOCAL_MACHINE',
    N'Software\Microsoft\MSSQLServer\MSSQLServer',
    N'DefaultData', 
    @defaultDataLocation OUTPUT

EXEC master.dbo.xp_instance_regread
    N'HKEY_LOCAL_MACHINE',
    N'Software\Microsoft\MSSQLServer\MSSQLServer',
    N'DefaultLog', 
    @defaultLogLocation OUTPUT

SELECT @defaultDataLocation AS 'Default Data Location',
       @defaultLogLocation AS 'Default Log Location'

How to fix org.hibernate.LazyInitializationException - could not initialize proxy - no Session

This exception because of when you call session.getEntityById(), the session will be closed. So you need to re-attach the entity to the session. Or Easy solution is just configure default-lazy="false" to your entity.hbm.xml or if you are using annotations just add @Proxy(lazy=false) to your entity class.

How do I create a message box with "Yes", "No" choices and a DialogResult?

MessageBox.Show(title, text, messageboxbuttons.yes/no)

This returns a DialogResult which you can check.

For example,

if(MessageBox.Show("","",MessageBoxButtons.YesNo) == DialogResult.Yes)
{
   //do something
}

How can I perform an inspect element in Chrome on my Galaxy S3 Android device?

To start with you'll need the Android SDK to get started: http://developer.android.com/sdk/index.html BUT select for existing IDE so you get the tools rather than all of Android Studio.

In Chrome Beta on your Android device do the following:

Menu > Settings > Developer Tools > Enable USB Debugging

Hit the home key on the device and go to Settings > Developer Options > Enable USB Debugging

[Note: If you can't see Developer Options, go to Settings > About Device > Then tap the Build Number a number of times and eventually you'll see a message saying you are now a developer or something similar]

Connect your phone to your Computer via USB

On your Desktop open Chrome Canary (I think stable and Beta currently have issues):

In the address bar type: chrome://flags and enable - "Enable Developer Tools experiments" and hit the Relaunch button that appears.

Once it's relaunched open a terminal and run adb devices, you should now see your device appear in the list. When it has, in Canary go to chrome://inspect there you will see your device, so now click inspect.

This will open up devtools for your Chrome on Android.

Now click on the cog in the corner, then go to Experiments > Enable Port Forwarding (If you don't see port forwarding, you might not be in Chrome Beta)

Once Port forwarding is enabled, close and open dev tools.

Go back to the cog and select Port Forwarding, then type in the port you want to forward (i.e. for locahost:9000 on my local machine I'd type 9000 [Device port] and 127.0.0.1:9000 [Target]

There is a bug open where the first port is ignored, so it might be worth hitting enter on the first line and re-entering the same details on the second line.

You can now put localhost:9000 (or your port number) in Chrome for Android and view the site and use DevTools to inspect the page.

More details under Reverse Port Forwarding section of this site: https://developers.google.com/chrome-developer-tools/docs/remote-debugging

How to prevent ENTER keypress to submit a web form?

I've always done it with a keypress handler like the above in the past, but today hit on a simpler solution. The enter key just triggers the first non-disabled submit button on the form, so actually all that's required is to intercept that button trying to submit:

<form>
  <div style="display: none;">
    <input type="submit" name="prevent-enter-submit" onclick="return false;">
  </div>
  <!-- rest of your form markup -->
</form>

That's it. Keypresses will be handled as usual by the browser / fields / etc. If the enter-submit logic is triggered, then the browser will find that hidden submit button and trigger it. And the javascript handler will then prevent the submision.

TypeError: Converting circular structure to JSON in nodejs

It's because you don't an async response For example:

app.get(`${api}/users`, async (req, res) => {
    const users = await User.find()
    res.send(users);
   })

SELECT COUNT in LINQ to SQL C#

Like that

var purchCount = (from purchase in myBlaContext.purchases select purchase).Count();

or even easier

var purchCount = myBlaContext.purchases.Count()

Send array with Ajax to PHP script

If you have been trying to send a one dimentional array and jquery was converting it to comma separated values >:( then follow the code below and an actual array will be submitted to php and not all the comma separated bull**it.

Say you have to attach a single dimentional array named myvals.

jQuery('#someform').on('submit', function (e) {
    e.preventDefault();
    var data = $(this).serializeArray();

    var myvals = [21, 52, 13, 24, 75]; // This array could come from anywhere you choose 
    for (i = 0; i < myvals.length; i++) {
        data.push({
            name: "myvals[]", // These blank empty brackets are imp!
            value: myvals[i]
        });
    }

jQuery.ajax({
    type: "post",
    url: jQuery(this).attr('action'),
    dataType: "json",
    data: data, // You have to just pass our data variable plain and simple no Rube Goldberg sh*t.
    success: function (r) {
...

Now inside php when you do this

print_r($_POST);

You will get ..

Array
(
    [someinputinsidetheform] => 023
    [anotherforminput] => 111
    [myvals] => Array
        (
            [0] => 21
            [1] => 52
            [2] => 13
            [3] => 24
            [4] => 75
        )
)

Pardon my language, but there are hell lot of Rube-Goldberg solutions scattered all over the web and specially on SO, but none of them are elegant or solve the problem of actually posting a one dimensional array to php via ajax post. Don't forget to spread this solution.

Blur or dim background when Android PopupWindow active

findViewById(R.id.drawer_layout).setAlpha((float) 0.7);

R.id.drawer_layout is the id of the layout of which you want to dim the brightness.

Oracle Sql get only month and year in date datatype

SELECT to_char(to_date(month,'yyyy-mm'),'Mon yyyy'), nos
FROM (SELECT to_char(credit_date,'yyyy-mm') MONTH,count(*) nos
      FROM HCN
      WHERE   TRUNC(CREDIT_dATE) BEtween '01-jul-2014' AND '30-JUN-2015'
      AND CATEGORYCODECFR=22
      --AND CREDIT_NOTE_NO IS NOT  NULL
      AND CANCELDATE IS NULL
GROUP BY to_char(credit_date,'yyyy-mm')
ORDER BY to_char(credit_date,'yyyy-mm') ) mm

Output:

Jul 2014        49
Aug 2014        35
Sep 2014        57
Oct 2014        50
Nov 2014        45
Dec 2014        88
Jan 2015       131
Feb 2015       112
Mar 2015        76
Apr 2015        45
May 2015        49
Jun 2015        40

How to sort the letters in a string alphabetically in Python

the code can be used to sort string in alphabetical order without using any inbuilt function of python

k = input("Enter any string again ")

li = []
x = len(k)
for i in range (0,x):
    li.append(k[i])

print("List is : ",li)


for i in range(0,x):
    for j in range(0,x):
        if li[i]<li[j]:
            temp = li[i]
            li[i]=li[j]
            li[j]=temp
j=""

for i in range(0,x):
    j = j+li[i]

print("After sorting String is : ",j)

Using GroupBy, Count and Sum in LINQ Lambda Expressions

        var q = from b in listOfBoxes
                group b by b.Owner into g
                select new
                           {
                               Owner = g.Key,
                               Boxes = g.Count(),
                               TotalWeight = g.Sum(item => item.Weight),
                               TotalVolume = g.Sum(item => item.Volume)
                           };

How do I update/upsert a document in Mongoose?

You were close with

Contact.update({phone:request.phone}, contact, {upsert: true}, function(err){...})

but your second parameter should be an object with a modification operator for example

Contact.update({phone:request.phone}, {$set: { phone: request.phone }}, {upsert: true}, function(err){...})

How to negate code in "if" statement block in JavaScript -JQuery like 'if not then..'

You can use the Logical NOT ! operator:

if (!$(this).parent().next().is('ul')){

Or equivalently (see comments below):

if (! ($(this).parent().next().is('ul'))){

For more information, see the Logical Operators section of the MDN docs.

json_encode/json_decode - returns stdClass instead of Array in PHP

There is also a good PHP 4 json encode / decode library (that is even PHP 5 reverse compatible) written about in this blog post: Using json_encode() and json_decode() in PHP4 (Jun 2009).

The concrete code is by Michal Migurski and by Matt Knapp:

How to grep for contents after pattern?

grep 'potato:' file.txt | sed 's/^.*: //'

grep looks for any line that contains the string potato:, then, for each of these lines, sed replaces (s/// - substitute) any character (.*) from the beginning of the line (^) until the last occurrence of the sequence : (colon followed by space) with the empty string (s/...// - substitute the first part with the second part, which is empty).

or

grep 'potato:' file.txt | cut -d\   -f2

For each line that contains potato:, cut will split the line into multiple fields delimited by space (-d\ - d = delimiter, \ = escaped space character, something like -d" " would have also worked) and print the second field of each such line (-f2).

or

grep 'potato:' file.txt | awk '{print $2}'

For each line that contains potato:, awk will print the second field (print $2) which is delimited by default by spaces.

or

grep 'potato:' file.txt | perl -e 'for(<>){s/^.*: //;print}'

All lines that contain potato: are sent to an inline (-e) Perl script that takes all lines from stdin, then, for each of these lines, does the same substitution as in the first example above, then prints it.

or

awk '{if(/potato:/) print $2}' < file.txt

The file is sent via stdin (< file.txt sends the contents of the file via stdin to the command on the left) to an awk script that, for each line that contains potato: (if(/potato:/) returns true if the regular expression /potato:/ matches the current line), prints the second field, as described above.

or

perl -e 'for(<>){/potato:/ && s/^.*: // && print}' < file.txt

The file is sent via stdin (< file.txt, see above) to a Perl script that works similarly to the one above, but this time it also makes sure each line contains the string potato: (/potato:/ is a regular expression that matches if the current line contains potato:, and, if it does (&&), then proceeds to apply the regular expression described above and prints the result).

Do I need to convert .CER to .CRT for Apache SSL certificates? If so, how?

The answer to the question how to convert a .cer file into a .crt file (they are encoded differently!) is:

openssl pkcs7 -print_certs -in certificate.cer -out certificate.crt

Return a "NULL" object if search result not found

You are unable to return NULL because the return type of the function is an object reference and not a pointer.

Set environment variables on Mac OS X Lion

Let me illustrate you from my personal example in a very redundant way.

  1. First after installing JDK, make sure it's installed. enter image description here
  2. Sometimes macOS or Linux automatically sets up environment variable for you unlike Windows. But that's not the case always. So let's check it. enter image description here The line immediately after echo $JAVA_HOME would be empty if the environment variable is not set. It must be empty in your case.

  3. Now we need to check if we have bash_profile file. enter image description here You saw that in my case we already have bash_profile. If not we have to create a bash_profile file.

  4. Create a bash_profile file. enter image description here

  5. Check again to make sure bash_profile file is there. enter image description here

  6. Now let's open bash_profile file. macOS opens it using it's default TextEdit program. enter image description here

  7. This is the file where environment variables are kept. If you have opened a new bash_profile file, it must be empty. In my case, it was already set for python programming language and Anaconda distribution. Now, i need to add environment variable for Java which is just adding the first line. YOU MUST TYPE the first line VERBATIM. JUST the first line. Save and close the TextEdit. Then close the terminal. enter image description here

  8. Open the terminal again. Let's check if the environment variable is set up. enter image description here

Use NSInteger as array index

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

AttributeError: 'str' object has no attribute 'append'

This is simple program showing append('t') to the list.
n=['f','g','h','i','k']

for i in range(1):
    temp=[]
    temp.append(n[-2:])
    temp.append('t')
    print(temp)

Output: [['i', 'k'], 't']

PHP float with 2 decimal places: .00

You can use this simple function. number_format ()

    $num = 2214.56;

    // default english notation
    $english_format = number_format($num);
    // 2,215

    // French notation
    $format_francais = number_format($num, 2, ',', ' ');
    // 2 214,56

    $num1 = 2234.5688;

   // English notation with thousands separator
    $english_format_number = number_format($num1,2);
    // 2,234.57

    // english notation without thousands separator
    $english_format_number2 = number_format($num1, 2, '.', '');
    // 2234.57

Difference between xcopy and robocopy

I have written lot of scripts to automate daily backups etc. Previously I used XCopy and then moved to Robocopy. Anyways Robocopy and XCopy both are frequently used in terms of file transfers in Windows. Robocopy stands for Robust File Copy. All type of huge file copying both these commands are used but Robocopy has added options which makes copying easier as well as for debugging purposes.

Having said that lets talk about features between these two.

  • Robocopy becomes handy for mirroring or synchronizing directories. It also checks the files in the destination directory against the files to be copied and doesn't waste time copying unchanged files.

  • Just like myself, if you are into automation to take daily backups etc, "Run Hours - /RH" becomes very useful without any interactions. This is supported by Robocopy. It allows you to set when copies should be done rather than the time of the command as with XCopy. You will see robocopy.exe process in task list since it will run background to monitor clock to execute when time is right to copy.

  • Robocopy supports file and directory monitoring with the "/MON" or "/MOT" commands.

  • Robocopy gives extra support for copying over the "archive" attribute on files, it supports copying over all attributes including timestamps, security, owner, and auditing information.

Hope this helps you.

VBA Subscript out of range - error 9

Option Explicit

Private Sub CommandButton1_Click()
Dim mode As String
Dim RecordId As Integer
Dim Resultid As Integer
Dim sourcewb As Workbook
Dim targetwb As Workbook
Dim SourceRowCount As Long
Dim TargetRowCount As Long
Dim SrceFile As String
Dim TrgtFile As String
Dim TitleId As Integer
Dim TestPassCount As Integer
Dim TestFailCount As Integer
Dim myWorkbook1 As Workbook
Dim myWorkbook2 As Workbook


TitleId = 4
Resultid = 0

Dim FileName1, FileName2 As String
Dim Difference As Long



'TestPassCount = 0
'TestFailCount = 0

'Retrieve number of records in the TestData SpreadSheet
Dim TestDataRowCount As Integer
TestDataRowCount = Worksheets("TestData").UsedRange.Rows.Count

If (TestDataRowCount <= 2) Then
  MsgBox "No records to validate.Please provide test data in Test Data SpreadSheet"
Else
  For RecordId = 3 To TestDataRowCount
    RefreshResultSheet

    'Source File row count
    SrceFile = Worksheets("TestData").Range("D" & RecordId).Value
    Set sourcewb = Workbooks.Open(SrceFile)
    With sourcewb.Worksheets(1)
      SourceRowCount = .Cells(.Rows.Count, "A").End(xlUp).row
      sourcewb.Close
    End With

    'Target File row count
    TrgtFile = Worksheets("TestData").Range("E" & RecordId).Value
    Set targetwb = Workbooks.Open(TrgtFile)
    With targetwb.Worksheets(1)
      TargetRowCount = .Cells(.Rows.Count, "A").End(xlUp).row
      targetwb.Close
    End With

    ' Set Row Count Result Test data value
    TitleId = TitleId + 3
    Worksheets("Result").Range("A" & TitleId).Value = Worksheets("TestData").Range("A" & RecordId).Value

    'Compare Source and Target Row count
    Resultid = TitleId + 1
    Worksheets("Result").Range("A" & Resultid).Value = "Source and Target record Count"
    If (SourceRowCount = TargetRowCount) Then
       Worksheets("Result").Range("B" & Resultid).Value = "Passed"
       Worksheets("Result").Range("C" & Resultid).Value = "Source Row Count: " & SourceRowCount & " & " & " Target Row Count: " & TargetRowCount
       TestPassCount = TestPassCount + 1
    Else
      Worksheets("Result").Range("B" & Resultid).Value = "Failed"
      Worksheets("Result").Range("C" & Resultid).Value = "Source Row Count: " & SourceRowCount & " & " & " Target Row Count: " & TargetRowCount
      TestFailCount = TestFailCount + 1
    End If


    'For comparison of two files

    FileName1 = Worksheets("TestData").Range("D" & RecordId).Value
    FileName2 = Worksheets("TestData").Range("E" & RecordId).Value

    Set myWorkbook1 = Workbooks.Open(FileName1)
    Set myWorkbook2 = Workbooks.Open(FileName2)

    Difference = Compare2WorkSheets(myWorkbook1.Worksheets("Sheet1"), myWorkbook2.Worksheets("Sheet1"))
    myWorkbook1.Close
    myWorkbook2.Close


    'MsgBox Difference

    'Set Result of data validation in result sheet
    Resultid = Resultid + 1

    Worksheets("Result").Activate
    Worksheets("Result").Range("A" & Resultid).Value = "Data validation of source and target File"

    If Difference > 0 Then
        Worksheets("Result").Range("B" & Resultid).Value = "Failed"
        Worksheets("Result").Range("C" & Resultid).Value = Difference & " cells contains different data!"
        TestFailCount = TestFailCount + 1
    Else
      Worksheets("Result").Range("B" & Resultid).Value = "Passed"
      Worksheets("Result").Range("C" & Resultid).Value = Difference & " cells contains different data!"
      TestPassCount = TestPassCount + 1
    End If


  Next RecordId
End If

UpdateTestExecData TestPassCount, TestFailCount
End Sub

Sub RefreshResultSheet()
  Worksheets("Result").Activate
  Worksheets("Result").Range("B1:B4").Select
  Selection.ClearContents
  Worksheets("Result").Range("D1:D4").Select
  Selection.ClearContents
  Worksheets("Result").Range("B1").Value = Worksheets("Instructions").Range("D3").Value
  Worksheets("Result").Range("B2").Value = Worksheets("Instructions").Range("D4").Value
  Worksheets("Result").Range("B3").Value = Worksheets("Instructions").Range("D6").Value
  Worksheets("Result").Range("B4").Value = Worksheets("Instructions").Range("D5").Value
End Sub

Sub UpdateTestExecData(TestPassCount As Integer, TestFailCount As Integer)
  Worksheets("Result").Range("D1").Value = TestPassCount + TestFailCount
  Worksheets("Result").Range("D2").Value = TestPassCount
  Worksheets("Result").Range("D3").Value = TestFailCount
  Worksheets("Result").Range("D4").Value = ((TestPassCount / (TestPassCount + TestFailCount)))
End Sub

What are the rules for calling the superclass constructor?

If you simply want to pass all constructor arguments to the base-class (=parent), here is a minimal example.

This uses templates to forward every constructor call with 1, 2 or 3 arguments to the parent class std::string.

Code

Live-Version

#include <iostream>
#include <string>

class ChildString: public std::string
{
    public:
        template<typename... Args>
        ChildString(Args... args): std::string(args...)
        {
            std::cout 
                << "\tConstructor call ChildString(nArgs="
                << sizeof...(Args) << "): " << *this
                << std::endl;
        }

};

int main()
{
    std::cout << "Check out:" << std::endl;
    std::cout << "\thttp://www.cplusplus.com/reference/string/string/string/" << std::endl;
    std::cout << "for available string constructors" << std::endl;

    std::cout << std::endl;
    std::cout << "Initialization:" << std::endl;
    ChildString cs1 ("copy (2)");

    char char_arr[] = "from c-string (4)";
    ChildString cs2 (char_arr);

    std::string str = "substring (3)";
    ChildString cs3 (str, 0, str.length());

    std::cout << std::endl;
    std::cout << "Usage:" << std::endl;
    std::cout << "\tcs1: " << cs1 << std::endl;
    std::cout << "\tcs2: " << cs2 << std::endl;
    std::cout << "\tcs3: " << cs3 << std::endl;

    return 0;
}

Output

Check out:
    http://www.cplusplus.com/reference/string/string/string/
for available string constructors

Initialization:
    Constructor call ChildString(nArgs=1): copy (2)
    Constructor call ChildString(nArgs=1): from c-string (4)
    Constructor call ChildString(nArgs=3): substring (3)

Usage:
    cs1: copy (2)
    cs2: from c-string (4)
    cs3: substring (3)

Update: Using Variadic Templates

To generalize to n arguments and simplify

        template <class C>
        ChildString(C arg): std::string(arg)
        {
            std::cout << "\tConstructor call ChildString(C arg): " << *this << std::endl;
        }
        template <class C1, class C2>
        ChildString(C1 arg1, C2 arg2): std::string(arg1, arg2)
        {
            std::cout << "\tConstructor call ChildString(C1 arg1, C2 arg2, C3 arg3): " << *this << std::endl;
        }
        template <class C1, class C2, class C3>
        ChildString(C1 arg1, C2 arg2, C3 arg3): std::string(arg1, arg2, arg3)
        {
            std::cout << "\tConstructor call ChildString(C1 arg1, C2 arg2, C3 arg3): " << *this << std::endl;
        }

to

template<typename... Args>
        ChildString(Args... args): std::string(args...)
        {
            std::cout 
                << "\tConstructor call ChildString(nArgs="
                << sizeof...(Args) << "): " << *this
                << std::endl;
        }

Java double.MAX_VALUE?

Double.MAX_VALUE is the maximum value a double can represent (somewhere around 1.7*10^308).

This should end in some calculation problems, if you try to subtract the maximum possible value of a data type.

Even though when you are dealing with money you should never use floating point values especially while rounding this can cause problems (you will either have to much or less money in your system then).

mvn command not found in OSX Mavrerick

steps to install maven :

  1. download the maven file from http://maven.apache.org/download.cgi
  2. $tar xvf apache-maven-3.5.4-bin.tar.gz
  3. copy the apache folder to desired place $cp -R apache-maven-3.5.4 /Users/locals
  4. go to apache directory $cd /Users/locals/apache-maven-3.5.4/
  5. create .bash_profile $vim ~/.bash_profile
  6. write these two command : export M2_HOME=/Users/manisha/apache-maven-3.5.4 export PATH=$PATH:$M2_HOME/bin 7 save and quit the vim :wq!
  7. restart the terminal and type mvn -version

Homebrew: Could not symlink, /usr/local/bin is not writable

For those who are looking for /usr/local/sbin is not writable error:

UPDATE: It could be /usr/local/someOtherFolderName e.g /usr/local/include. You just need to create that folder with:

  • sudo mkdir someOtherFolderName

First create the sbin folder, note that this requires sudo privileges

  • cd /usr/local

  • sudo mkdir sbin

  • sudo chown -R $(whoami) $(brew --prefix)/*

  • brew link yourPackageName

org.springframework.beans.factory.BeanCreationException: Error creating bean with name

you need to add jar file in your build path..

commons-dbcp-1.1-RC2.jar

or any version of that..!!!!

ADDED : also make sure you have commons-pool-1.1.jar too in your build path.

ADDED: sorry saw complete list of jar late... may be version clashes might be there.. better check out..!!! just an assumption.

How do I properly 'printf' an integer and a string in C?

Try this code my friend...

#include<stdio.h>
int main(){
   char *s1, *s2;
   char str[10];

   printf("type a string: ");
   scanf("%s", str);

   s1 = &str[0];
   s2 = &str[2];

   printf("%c\n", *s1);   //use %c instead of %s and *s1 which is the content of position 1
   printf("%c\n", *s2);   //use %c instead of %s and *s3 which is the content of position 1

   return 0;
}

How to call function that takes an argument in a Django template?

By design, Django templates cannot call into arbitrary Python code. This is a security and safety feature for environments where designers write templates, and it also prevents business logic migrating into templates.

If you want to do this, you can switch to using Jinja2 templates (http://jinja.pocoo.org/docs/), or any other templating system you like that supports this. No other part of django will be affected by the templates you use, because it is intentionally a one-way process. You could even use many different template systems in the same project if you wanted.

How do I return to an older version of our code in Subversion?

Sync to the older version and commit it. This should do the trick.

Here's also an explanation of undoing changes.

PLS-00428: an INTO clause is expected in this SELECT statement

In PLSQL block, columns of select statements must be assigned to variables, which is not the case in SQL statements.

The second BEGIN's SQL statement doesn't have INTO clause and that caused the error.

DECLARE
   PROD_ROW_ID   VARCHAR (10) := NULL;
   VIS_ROW_ID    NUMBER;
   DSC           VARCHAR (512);
BEGIN
   SELECT ROW_ID
     INTO VIS_ROW_ID
     FROM SIEBEL.S_PROD_INT
    WHERE PART_NUM = 'S0146404';

   BEGIN
      SELECT    RTRIM (VIS.SERIAL_NUM)
             || ','
             || RTRIM (PLANID.DESC_TEXT)
             || ','
             || CASE
                   WHEN PLANID.HIGH = 'TEST123'
                   THEN
                      CASE
                         WHEN TO_DATE (PROD.START_DATE) + 30 > SYSDATE
                         THEN
                            'Y'
                         ELSE
                            'N'
                      END
                   ELSE
                      'N'
                END
             || ','
             || 'GB'
             || ','
             || RTRIM (TO_CHAR (PROD.START_DATE, 'YYYY-MM-DD'))
        INTO DSC
        FROM SIEBEL.S_LST_OF_VAL PLANID
             INNER JOIN SIEBEL.S_PROD_INT PROD
                ON PROD.PART_NUM = PLANID.VAL
             INNER JOIN SIEBEL.S_ASSET NETFLIX
                ON PROD.PROD_ID = PROD.ROW_ID
             INNER JOIN SIEBEL.S_ASSET VIS
                ON VIS.PROM_INTEG_ID = PROD.PROM_INTEG_ID
             INNER JOIN SIEBEL.S_PROD_INT VISPROD
                ON VIS.PROD_ID = VISPROD.ROW_ID
       WHERE     PLANID.TYPE = 'Test Plan'
             AND PLANID.ACTIVE_FLG = 'Y'
             AND VISPROD.PART_NUM = VIS_ROW_ID
             AND PROD.STATUS_CD = 'Active'
             AND VIS.SERIAL_NUM IS NOT NULL;
   END;
END;
/

References

http://docs.oracle.com/cd/E11882_01/appdev.112/e25519/static.htm#LNPLS00601 http://docs.oracle.com/cd/B19306_01/appdev.102/b14261/selectinto_statement.htm#CJAJAAIG http://pls-00428.ora-code.com/

How to run a program in Atom Editor?

You can try to use the runner in atom Hit Ctrl+R (Alt+R on Win/Linux) to launch the runner for the active window. Hit Ctrl+Shift+R (Alt+Shift+R on Win/Linux) to run the currently selected text in the active window. Hit Ctrl+Shift+C to kill a currently running process. Hit Escape to close the runner window

Pagination using MySQL LIMIT, OFFSET

First off, don't have a separate server script for each page, that is just madness. Most applications implement pagination via use of a pagination parameter in the URL. Something like:

http://yoursite.com/itempage.php?page=2

You can access the requested page number via $_GET['page'].

This makes your SQL formulation really easy:

// determine page number from $_GET
$page = 1;
if(!empty($_GET['page'])) {
    $page = filter_input(INPUT_GET, 'page', FILTER_VALIDATE_INT);
    if(false === $page) {
        $page = 1;
    }
}

// set the number of items to display per page
$items_per_page = 4;

// build query
$offset = ($page - 1) * $items_per_page;
$sql = "SELECT * FROM menuitem LIMIT " . $offset . "," . $items_per_page;

So for example if input here was page=2, with 4 rows per page, your query would be"

SELECT * FROM menuitem LIMIT 4,4

So that is the basic problem of pagination. Now, you have the added requirement that you want to understand the total number of pages (so that you can determine if "NEXT PAGE" should be shown or if you wanted to allow direct access to page X via a link).

In order to do this, you must understand the number of rows in the table.

You can simply do this with a DB call before trying to return your actual limited record set (I say BEFORE since you obviously want to validate that the requested page exists).

This is actually quite simple:

$sql = "SELECT your_primary_key_field FROM menuitem";
$result = mysqli_query($con, $sql);
if(false === $result) {
   throw new Exception('Query failed with: ' . mysqli_error());
} else {
   $row_count = mysqli_num_rows($result);
   // free the result set as you don't need it anymore
   mysqli_free_result($result);
}

$page_count = 0;
if (0 === $row_count) {  
    // maybe show some error since there is nothing in your table
} else {
   // determine page_count
   $page_count = (int)ceil($row_count / $items_per_page);
   // double check that request page is in range
   if($page > $page_count) {
        // error to user, maybe set page to 1
        $page = 1;
   }
}

// make your LIMIT query here as shown above


// later when outputting page, you can simply work with $page and $page_count to output links
// for example
for ($i = 1; $i <= $page_count; $i++) {
   if ($i === $page) { // this is current page
       echo 'Page ' . $i . '<br>';
   } else { // show link to other page   
       echo '<a href="/menuitem.php?page=' . $i . '">Page ' . $i . '</a><br>';
   }
}

to_string is not a member of std, says g++ (mingw)

#include <string>
#include <sstream>

namespace patch
{
    template < typename T > std::string to_string( const T& n )
    {
        std::ostringstream stm ;
        stm << n ;
        return stm.str() ;
    }
}

#include <iostream>

int main()
{
    std::cout << patch::to_string(1234) << '\n' << patch::to_string(1234.56) << '\n' ;
}

do not forget to include #include <sstream>

How to create a generic array?

Problem is that while runtime generic type is erased so new E[10] would be equivalent to new Object[10].

This would be dangerous because it would be possible to put in array other data than of E type. That is why you need to explicitly say that type you want by either

invalid byte sequence for encoding "UTF8"

Apparently I can just set the encoding on the fly,

 set client_encoding to 'latin1'

And then re-run the query. Not sure what encoding I should be using though.


latin1 made the characters legible, but most of the accented characters were in upper-case where they shouldn't have been. I assumed this was due to a bad encoding, but I think its actually the data that was just bad. I ended up keeping the latin1 encoding, but pre-processing the data and fixed the casing issues.

How to read a list of files from a folder using PHP?

The simplest and most fun way (imo) is glob

foreach (glob("*.*") as $filename) {
    echo $filename."<br />";
}

But the standard way is to use the directory functions.

if (is_dir($dir)) {
    if ($dh = opendir($dir)) {
        while (($file = readdir($dh)) !== false) {
            echo "filename: .".$file."<br />";
        }
        closedir($dh);
    }
}

There are also the SPL DirectoryIterator methods. If you are interested

XAMPP permissions on Mac OS X?

What worked for me was,

  • Open Terminal from the XAMPP app,
  • type in this,

chmod -R 0777 /opt/lampp/htdocs/

Can I install the "app store" in an IOS simulator?

This is NOT possible

The Simulator does not run ARM code, ONLY x86 code. Unless you have the raw source code from Apple, you won't see the App Store on the Simulator.

The app you write you will be able to test in the Simulator by running it directly from Xcode even if you don't have a developer account. To test your app on an actual device, you will need to be apart of the Apple Developer program.

Allowed memory size of 33554432 bytes exhausted (tried to allocate 43148176 bytes) in php

I hadn't renewed my hosting and the database was read-only. Joomla needed to write the session and couldn't do it.

The SELECT permission was denied on the object 'Users', database 'XXX', schema 'dbo'

This is how I was able to solve the problem when I faced it

  1. Start SQL Management Studio.
  2. Expand the Server Node (in the 'Object Explorer').
  3. Expand the Databases Node and then expand the specific Database which you are trying to access using the specific user.
  4. Expand the Users node under the Security node for the database.
  5. Right click the specific user and click 'properties'. You will get a dialog box.
  6. Make sure the user is a member of the db_owner group (please read the comments below before you use go this path) and other required changes using the view. (I used this for 2016. Not sure how the specific dialog look like in other version and hence not being specific)

What is the best way to declare global variable in Vue.js?

a vue3 replacement of this answer:

// Vue3

const app = Vue.createApp({})
app.config.globalProperties.$hostname = 'http://localhost:3000'


app.component('a-child-component', {
  mounted() {
    console.log(this.$hostname) // 'http://localhost:3000'
  }
})

How to extract a string using JavaScript Regex?

This code works:

  let str = "governance[string_i_want]"; 
  let res = str.match(/[^governance\[](.*)[^\]]/g);

res will equal "string_i_want". However, in this example res is still an array, so do not treat res like a string.

By grouping the characters I do not want, using [^string], and matching on what is between the brackets, the code extracts the string I want!

You can try it out here: https://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_match_regexp

Good luck.

function to remove duplicate characters in a string

    String s = "Javajk";
    List<Character> charz = new ArrayList<Character>();
    for (Character c : s.toCharArray()) {
        if (!(charz.contains(Character.toUpperCase(c)) || charz
                .contains(Character.toLowerCase(c)))) {
            charz.add(c);
        }
    }
     ListIterator litr = charz.listIterator();
   while (litr.hasNext()) {

       Object element = litr.next();
       System.err.println(":" + element);

   }    }

this will remove the duplicate if the character present in both the case.

How to validate an Email in PHP?

Use:

var_dump(filter_var('[email protected]', FILTER_VALIDATE_EMAIL));
$validator = new EmailValidator();
$multipleValidations = new MultipleValidationWithAnd([
    new RFCValidation(),
    new DNSCheckValidation()
]);
$validator->isValid("[email protected]", $multipleValidations); //true

Showing empty view when ListView is empty

When you extend FragmentActivity or Activity and not ListActivity, you'll want to take a look at:

ListView.setEmptyView()

How to monitor SQL Server table changes by using c#?

looks like bad architecture all the way. also you have not specified the type of app you need to notify to (web app / console app / winforms / service etc etc)

nevertheless, to answer your question, there are multiple ways of solving this. you could use:

1) timestamps if you were just interested in ensuring the next set of updates from the second app dont conflict with the updates from the first app

2) sql dependency object - see http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldependency.aspx for more info

3) a custom push notification service which multiple clients (web / winform / service) can subscribe to and get notified on changes

in short, you need to use the simplest and easiest and cheapest (in terms of efforts) solution based on how complex your notification requirements are and for what purpose you need to use them. dont try to build an overly complex notification system if a simple data concurrency is your only requirement (in that case go for a simple timestamp based solution)

Python creating a dictionary of lists

Your question has already been answered, but IIRC you can replace lines like:

if d.has_key(scope_item):

with:

if scope_item in d:

That is, d references d.keys() in that construction. Sometimes defaultdict isn't the best option (for example, if you want to execute multiple lines of code after the else associated with the above if), and I find the in syntax easier to read.

HTTP response code for POST when resource already exists

Personally I go with the WebDAV extension 422 Unprocessable Entity.

According to RFC 4918

The 422 Unprocessable Entity status code means the server understands the content type of the request entity (hence a 415 Unsupported Media Type status code is inappropriate), and the syntax of the request entity is correct (thus a 400 Bad Request status code is inappropriate) but was unable to process the contained instructions.

How to obtain the start time and end time of a day?

in getEndOfDay, you can add:

calendar.set(Calendar.MILLISECOND, 999);

Although mathematically speaking, you can't specify the end of a day other than by saying it's "before the beginning of the next day".

So instead of saying, if(date >= getStartOfDay(today) && date <= getEndOfDay(today)), you should say: if(date >= getStartOfDay(today) && date < getStartOfDay(tomorrow)). That is a much more solid definition (and you don't have to worry about millisecond precision).

What is .Net Framework 4 extended?

It's the part of the .NET Framework that isn't contained within the Client Profile. See MSDN for more info; specifically:

The .NET Framework is made up of the .NET Framework 4 Client Profile and .NET Framework 4 Extended components that exist separately in Programs and Features.

Java Multiple Inheritance

I think it depends very much on your needs, and how your animal classes are to be used in your code.

If you want to be able to make use of methods and features of your Horse and Bird implementations inside your Pegasus class, then you could implement Pegasus as a composition of a Bird and a Horse:

public class Animals {

    public interface Animal{
        public int getNumberOfLegs();
        public boolean canFly();
        public boolean canBeRidden();
    }

    public interface Bird extends Animal{
        public void doSomeBirdThing();
    }
    public interface Horse extends Animal{
        public void doSomeHorseThing();
    }
    public interface Pegasus extends Bird,Horse{

    }

    public abstract class AnimalImpl implements Animal{
        private final int numberOfLegs;

        public AnimalImpl(int numberOfLegs) {
            super();
            this.numberOfLegs = numberOfLegs;
        }

        @Override
        public int getNumberOfLegs() {
            return numberOfLegs;
        }
    }

    public class BirdImpl extends AnimalImpl implements Bird{

        public BirdImpl() {
            super(2);
        }

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

        @Override
        public boolean canBeRidden() {
            return false;
        }

        @Override
        public void doSomeBirdThing() {
            System.out.println("doing some bird thing...");
        }

    }

    public class HorseImpl extends AnimalImpl implements Horse{

        public HorseImpl() {
            super(4);
        }

        @Override
        public boolean canFly() {
            return false;
        }

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

        @Override
        public void doSomeHorseThing() {
            System.out.println("doing some horse thing...");
        }

    }

    public class PegasusImpl implements Pegasus{

        private final Horse horse = new HorseImpl();
        private final Bird bird = new BirdImpl();


        @Override
        public void doSomeBirdThing() {
            bird.doSomeBirdThing();
        }

        @Override
        public int getNumberOfLegs() {
            return horse.getNumberOfLegs();
        }

        @Override
        public void doSomeHorseThing() {
            horse.doSomeHorseThing();
        }


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

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

Another possibility is to use an Entity-Component-System approach instead of inheritance for defining your animals. Of course this means, that you will not have individual Java classes of the animals, but instead they are only defined by their components.

Some pseudo code for an Entity-Component-System approach could look like this:

public void createHorse(Entity entity){
    entity.setComponent(NUMER_OF_LEGS, 4);
    entity.setComponent(CAN_FLY, false);
    entity.setComponent(CAN_BE_RIDDEN, true);
    entity.setComponent(SOME_HORSE_FUNCTIONALITY, new HorseFunction());
}

public void createBird(Entity entity){
    entity.setComponent(NUMER_OF_LEGS, 2);
    entity.setComponent(CAN_FLY, true);
    entity.setComponent(CAN_BE_RIDDEN, false);
    entity.setComponent(SOME_BIRD_FUNCTIONALITY, new BirdFunction());
}

public void createPegasus(Entity entity){
    createHorse(entity);
    createBird(entity);
    entity.setComponent(CAN_BE_RIDDEN, true);
}

How to change a particular element of a C++ STL vector

at and operator[] both return a reference to the indexed element, so you can simply use:

l.at(4) = -1;

or

l[4] = -1;

How to update fields in a model without creating a new record in django?

Sometimes it may be required to execute the update atomically that is using one update request to the database without reading it first.

Also get-set attribute-save may cause problems if such updates may be done concurrently or if you need to set the new value based on the old field value.

In such cases query expressions together with update may by useful:

TemperatureData.objects.filter(id=1).update(value=F('value') + 1)

Bootstrap 4 responsive tables won't take up 100% width

I found that using the recommended table-responsive class in a wrapper still causes responsive tables to (surprisingly) shrink horizontally:

<div class="table-responsive-lg">
    <table class="table">
        ...
    </table>
</div>

The solution for me was to create the following media breakpoints and classes to prevent it:

.table-xs {
    width:544px;
}

.table-sm {
    width: 576px;
}

.table-md {
    width: 768px;
}

.table-lg {
    width: 992px;
}

.table-xl {
    width: 1200px;
}

/* Small devices (landscape phones, 544px and up) */
@media (min-width: 576px) {  
    .table-sm {
        width: 100%;
    }
}

/* Medium devices (tablets, 768px and up) The navbar toggle appears at this breakpoint */
@media (min-width: 768px) {
    .table-sm {
        width: 100%;
    }

    .table-md {
        width: 100%;
    }
}

/* Large devices (desktops, 992px and up) */
@media (min-width: 992px) {
    .table-sm {
        width: 100%;
    }

    .table-md {
        width: 100%;
    }

    .table-lg {
        width: 100%;
    }
}

/* Extra large devices (large desktops, 1200px and up) */
@media (min-width: 1200px) {
    .table-sm {
        width: 100%;
    }

    .table-md {
        width: 100%;
    }

    .table-lg {
        width: 100%;
    }

    .table-xl {
        width: 100%;
    }
}

Then I can add the appropriate class to my table element. For example:

<div class="table-responsive-lg">
    <table class="table table-lg">
        ...
    </table>
</div>

Here the wrapper sets the width to 100% for large and greater per Bootstrap. With the table-lg class applied to the table element, the table width is set also set to 100% for large and greater, but set to 992px for medium and smaller. The classes table-xs, table-sm, table-md, and table-xl work the same way.

How do I center content in a div using CSS?

with all the adjusting css. if possible, wrap it with a table with height and width as 100% and td set it to vertical align to middle, text-align to center

How do I disable directory browsing?

Add this in your .htaccess file:

Options -Indexes

If it is not work for any reason, try this within your .htaccess file:

IndexIgnore *

Notepad++ change text color?

You can use the "User-Defined Language" option available at the notepad++. You do not need to do the xml-based hacks, where the formatting would be available only in the searched window, with the formatting rules.

Sample for your reference here.

Are HTTPS URLs encrypted?

Yes, the SSL connection is between the TCP layer and the HTTP layer. The client and server first establish a secure encrypted TCP connection (via the SSL/TLS protocol) and then the client will send the HTTP request (GET, POST, DELETE...) over that encrypted TCP connection.

Can't specify the 'async' modifier on the 'Main' method of a console app

In C# 7.1 you will be able to do a proper async Main. The appropriate signatures for Main method has been extended to:

public static Task Main();
public static Task<int> Main();
public static Task Main(string[] args);
public static Task<int> Main(string[] args);

For e.g. you could be doing:

static async Task Main(string[] args)
{
    Bootstrapper bs = new Bootstrapper();
    var list = await bs.GetList();
}

At compile time, the async entry point method will be translated to call GetAwaitor().GetResult().

Details: https://blogs.msdn.microsoft.com/mazhou/2017/05/30/c-7-series-part-2-async-main

EDIT:

To enable C# 7.1 language features, you need to right-click on the project and click "Properties" then go to the "Build" tab. There, click the advanced button at the bottom:

enter image description here

From the language version drop-down menu, select "7.1" (or any higher value):

enter image description here

The default is "latest major version" which would evaluate (at the time of this writing) to C# 7.0, which does not support async main in console apps.

How do I get a HttpServletRequest in my spring beans?

This is kind of Flex/BlazeDS specific, but here's the solution I've come up with. Sorry if answering my own question is a faux pas.

    HttpServletRequest request = flex.messaging.FlexContext.getHttpRequest();

    Cookie[] cookies = request.getCookies();

    for (Cookie c:cookies)
    {
        log.debug(String.format("Cookie: %s, %s, domain: %s",c.getName(), c.getValue(),c.getDomain()));
    }

It works, I get the cookies. My problem was looking to Spring - BlazeDS had it. Spring probably does too, but I still don't know how to get to it.

java.lang.ClassNotFoundException: org.springframework.core.io.Resource

There is a version conflict between jar/dependency please check all version of spring is same. if you use maven remove version of dependency and use Spring.io dependency.it handle version conflict. Add this in your pom

 <dependency>
            <groupId>io.spring.platform</groupId>
            <artifactId>platform-bom</artifactId>
            <version>2.0.1.RELEASE</version>
            <type>pom</type>
            <scope>import</scope>
  </dependency>

ASP.NET Web Application Message Box

As others already pointed out, a message box will be clientside Javascript. So the problem then is how to force a clientside JS message box from the server side. A simple solution is to include this in the HTML:

<script>
    var data = '<%= JsData %>';
    alert(data);
</script>

and to fill this data from the server side code-behind:

public partial class PageName : Page
{
    protected string JsData = "your message";

Note that the string value should be a Javascript string, i.e. be a one-liner, but it may contain escaped newlines as \n.

Now you can use all your Javascript or JQuery skills and tricks to do whatever you want with that message text on the clientside, such as display a simple alert(), as shown in the above code sample, or sophisticated message box or message banner.

(Note that popups are sometimes frowned upon and blocked)

Note also that, due to the HTTP protocol, the message can only be shown in response to an HTTP request that the user sends to the server. Unlike WinForm apps, the web server cannot push a message to the client whenever it sees fit.

If you want to show the message only once, and not after the user refreshes the page with F5, you could set and read a cookie with javascript code. In any case, the nice point with this method is that it is an easy way to get data from the server to the javascript on the client, and that you can use all javascript features to accomplish anything you like.

ERROR 1698 (28000): Access denied for user 'root'@'localhost'

This has happened to me as well. The problem is with the mysql repo that comes already with the linux distro. So when you simply do: $ sudo apt install mysql-server it installs mysql from their default repo which gives this problem. So to overcome that you need to uninstall that installed mysql $ sudo apt remove mysql* --purge --auto-remove

Then download mysql repo from official mysql website MySQL APT Repo Follow their documentation on how to add repo and install it. This gives no issue. Also as answered by @zetacu, you can verify that mysql root now indeed uses mysql_native_password plugin

Bootstrap 3: how to make head of dropdown link clickable in navbar

Alternatively here's a simple jQuery solution:

$('#menu-main > li > .dropdown-toggle').click(function () {
    window.location = $(this).attr('href');
});

Getting HTTP code in PHP using curl

// must set $url first....
$http = curl_init($url);
// do your curl thing here
$result = curl_exec($http);
$http_status = curl_getinfo($http, CURLINFO_HTTP_CODE);
curl_close($http);
echo $http_status;

Left Outer Join using + sign in Oracle 11g

There is some incorrect information in this thread. I copied and pasted the incorrect information:

LEFT OUTER JOIN

SELECT *
FROM A, B
WHERE A.column = B.column(+)

RIGHT OUTER JOIN

SELECT *
FROM A, B
WHERE B.column(+) = A.column

The above is WRONG!!!!! It's reversed. How I determined it's incorrect is from the following book:

Oracle OCP Introduction to Oracle 9i: SQL Exam Guide. Page 115 Table 3-1 has a good summary on this. I could not figure why my converted SQL was not working properly until I went old school and looked in a printed book!

Here is the summary from this book, copied line by line:

Oracle outer Join Syntax:

from tab_a a, tab_b b,                                       
where a.col_1 + = b.col_1                                     

ANSI/ISO Equivalent:

from tab_a a left outer join  
tab_b b on a.col_1 = b.col_1

Notice here that it's the reverse of what is posted above. I suppose it's possible for this book to have errata, however I trust this book more so than what is in this thread. It's an exam guide for crying out loud...

How to get access to raw resources that I put in res folder?

InputStream in = getResources().openRawResource(resourceName);

This will work correctly. Before that you have to create the xml file / text file in raw resource. Then it will be accessible.

Edit
Some times com.andriod.R will be imported if there is any error in layout file or image names. So You have to import package correctly, then only the raw file will be accessible.

How to get input type using jquery?

You could do the following:

var inputType = $('#inputid').attr('type');

How can I get Maven to stop attempting to check for updates for artifacts from a certain group from maven-central-repo?

The updatePolicy tag didn't work for me. However Rich Seller mentioned that snapshots should be disabled anyways so I looked further and noticed that the extra repository that I added to my settings.xml was causing the problem actually. Adding the snapshots section to this repository in my settings.xml did the trick!

<repository>
    <id>jboss</id>
    <name>JBoss Repository</name>
    <url>http://repository.jboss.com/maven2</url>
    <snapshots>
        <enabled>false</enabled>
    </snapshots>
</repository>

Why does CreateProcess give error 193 (%1 is not a valid Win32 app)

If you are Clion/anyOtherJetBrainsIDE user, and yourFile.exe cause this problem, just delete it and let the app create and link it with libs from a scratch. It helps.

Sorting Characters Of A C++ String

You can use sort() function. sort() exists in algorithm header file

        #include<bits/stdc++.h>
        using namespace std;


        int main()
        {
            ios::sync_with_stdio(false);
            string str = "sharlock";

            sort(str.begin(), str.end());
            cout<<str<<endl;

            return 0;
        }

Output:

achklors

How can I get the first two digits of a number?

You can use a regular expression to test for a match and capture the first two digits:

import re

for i in range(1000):
    match = re.match(r'(1[56])', str(i))

    if match:
        print(i, 'begins with', match.group(1))

The regular expression (1[56]) matches a 1 followed by either a 5 or a 6 and stores the result in the first capturing group.

Output:

15 begins with 15
16 begins with 16
150 begins with 15
151 begins with 15
152 begins with 15
153 begins with 15
154 begins with 15
155 begins with 15
156 begins with 15
157 begins with 15
158 begins with 15
159 begins with 15
160 begins with 16
161 begins with 16
162 begins with 16
163 begins with 16
164 begins with 16
165 begins with 16
166 begins with 16
167 begins with 16
168 begins with 16
169 begins with 16

Set Background color programmatically

you need to use getResources() method, try to use following code

View someView = findViewById(R.id.screen);
View root = someView.getRootView();
root.setBackgroundColor(getResources().getColor(color.white)); 

Edit::

getResources.getColor() is deprecated so, use like below

 root.setBackgroundColor(ContextCompat.getColor(this, R.color.white)); 

How do I call one constructor from another in Java?

You can a constructor from another constructor of same class by using "this" keyword. Example -

class This1
{
    This1()
    {
        this("Hello");
        System.out.println("Default constructor..");
    }
    This1(int a)
    {
        this();
        System.out.println("int as arg constructor.."); 
    }
    This1(String s)
    {
        System.out.println("string as arg constructor..");  
    }

    public static void main(String args[])
    {
        new This1(100);
    }
}

Output - string as arg constructor.. Default constructor.. int as arg constructor..

Set up a scheduled job?

Interesting new pluggable Django app: django-chronograph

You only have to add one cron entry which acts as a timer, and you have a very nice Django admin interface into the scripts to run.

Convert Java Date to UTC String

tl;dr

You asked:

I was looking for a one-liner like:

Ask and ye shall receive. Convert from terrible legacy class Date to its modern replacement, Instant.

myJavaUtilDate.toInstant().toString()

2020-05-05T19:46:12.912Z

java.time

In Java 8 and later we have the new java.time package built in (Tutorial). Inspired by Joda-Time, defined by JSR 310, and extended by the ThreeTen-Extra project.

The best solution is to sort your date-time objects rather than strings. But if you must work in strings, read on.

An Instant represents a moment on the timeline, basically in UTC (see class doc for precise details). The toString implementation uses the DateTimeFormatter.ISO_INSTANT format by default. This format includes zero, three, six or nine digits digits as needed to display fraction of a second up to nanosecond precision.

String output = Instant.now().toString(); // Example: '2015-12-03T10:15:30.120Z'

If you must interoperate with the old Date class, convert to/from java.time via new methods added to the old classes. Example: Date::toInstant.

myJavaUtilDate.toInstant().toString()

You may want to use an alternate formatter if you need a consistent number of digits in the fractional second or if you need no fractional second.

Another route if you want to truncate fractions of a second is to use ZonedDateTime instead of Instant, calling its method to change the fraction to zero.

Note that we must specify a time zone for ZonedDateTime (thus the name). In our case that means UTC. The subclass of ZoneID, ZoneOffset, holds a convenient constant for UTC. If we omit the time zone, the JVM’s current default time zone is implicitly applied.

String output = ZonedDateTime.now( ZoneOffset.UTC ).withNano( 0 ).toString();  // Example: 2015-08-27T19:28:58Z

Table of date-time types in Java, both modern and legacy


About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.

Where to obtain the java.time classes?


Joda-Time

UPDATE: The Joda -Time project is now in maintenance mode, with the team advising migration to the java.time classes.

I was looking for a one-liner

Easy if using the Joda-Time 2.3 library. ISO 8601 is the default formatting.

Time Zone

In the code example below, note that I am specifying a time zone rather than depending on the default time zone. In this case, I'm specifying UTC per your question. The Z on the end, spoken as "Zulu", means no time zone offset from UTC.

Example Code

// import org.joda.time.*;

String output = new DateTime( DateTimeZone.UTC );

Output…

2013-12-12T18:29:50.588Z

Exception is never thrown in body of corresponding try statement

As pointed out in the comments, you cannot catch an exception that's not thrown by the code within your try block. Try changing your code to:

try{
    Integer.parseInt(args[i-1]); // this only throws a NumberFormatException
}
catch(NumberFormatException e){
    throw new MojException("Bledne dane");
}

Always check the documentation to see what exceptions are thrown by each method. You may also wish to read up on the subject of checked vs unchecked exceptions before that causes you any confusion in the future.

String's Maximum length in Java - calling length() method

apparently it's bound to an int, which is 0x7FFFFFFF (2147483647).

Visual Studio Code includePath

My c_cpp_properties.json config-

{
    "configurations": [
        {
            "name": "Win32",
            "compilerPath": "C:/MinGW/bin/g++.exe",
            "includePath": [
                "C:/MinGW/lib/gcc/mingw32/9.2.0/include/c++"
            ],
            "defines": [
                "_DEBUG",
                "UNICODE",
                "_UNICODE"
            ],
            "cStandard": "c17",
            "cppStandard": "c++17",
            "intelliSenseMode": "windows-gcc-x64"
       }
    ],
    "version": 4
}

Concatenate two string literals

You should always pay attention to types.

Although they all seem like strings, "Hello" and ",world" are literals.

And in your example, exclam is a std::string object.

C++ has an operator overload that takes a std::string object and adds another string to it. When you concatenate a std::string object with a literal it will make the appropriate casting for the literal.

But if you try to concatenate two literals, the compiler won't be able to find an operator that takes two literals.

How to iterate through two lists in parallel?

Python 3:

import itertools as it

for foo, bar in list(it.izip_longest(list1, list2)):
    print(foo, bar)

jQuery - simple input validation - "empty" and "not empty"

    jQuery("#input").live('change', function() {
        // since we check more than once against the value, place it in a var.
        var inputvalue = $("#input").attr("value");

        // if it's value **IS NOT** ""
        if(inputvalue !== "") {
            jQuery(this).css('outline', 'solid 1px red'); 
        }   

        // else if it's value **IS** ""
        else if(inputvalue === "") {
            alert('empty'); 
        }

    });

How to calculate the median of an array?

Check out the Arrays.sort methods:

http://docs.oracle.com/javase/6/docs/api/java/util/Arrays.html

You should also really abstract finding the median into its own method, and just return the value to the calling method. This will make testing your code much easier.

How can I create an array/list of dictionaries in python?

Minor variation to user1850980's answer (for the question "How to initialize a list of empty dictionaries") using list constructor:

dictlistGOOD = list( {} for i in xrange(listsize) )

I found out to my chagrin, this does NOT work:

dictlistFAIL = [{}] * listsize  # FAIL!

as it creates a list of references to the same empty dictionary, so that if you update one dictionary in the list, all the other references get updated too.

Try these updates to see the difference:

dictlistGOOD[0]["key"] = "value"
dictlistFAIL[0]["key"] = "value"

(I was actually looking for user1850980's answer to the question asked, so his/her answer was helpful.)

How to concatenate string variables in Bash

var1='hello'
var2='world'
var3=$var1" "$var2 
echo $var3

Converting JSONarray to ArrayList

I have fast solution. Just create a file ArrayUtil.java

ObjectMapper mapper = new ObjectMapper(); 
List<Student> list = Arrays.asList(mapper.readValue(jsonString, Student[].class));

Usage:

ArrayList<Object> list = ArrayUtil.convert(jArray);

or

JSONArray jArr = ArrayUtil.convert(list);

Randomize a List<T>

Here is an implementation of the Fisher-Yates shuffle that allows specification of the number of elements to return; hence, it is not necessary to first sort the whole collection before taking your desired number of elements.

The sequence of swapping elements is reversed from default; and proceeds from the first element to the last element, so that retrieving a subset of the collection yields the same (partial) sequence as shuffling the whole collection:

collection.TakeRandom(5).SequenceEqual(collection.Shuffle().Take(5)); // true

This algorithm is based on Durstenfeld's (modern) version of the Fisher-Yates shuffle on Wikipedia.

public static IList<T> TakeRandom<T>(this IEnumerable<T> collection, int count, Random random) => shuffle(collection, count, random);
public static IList<T> Shuffle<T>(this IEnumerable<T> collection, Random random) => shuffle(collection, null, random);
private static IList<T> shuffle<T>(IEnumerable<T> collection, int? take, Random random)
{
    var a = collection.ToArray();
    var n = a.Length;
    if (take <= 0 || take > n) throw new ArgumentException("Invalid number of elements to return.");
    var end = take ?? n;
    for (int i = 0; i < end; i++)
    {
        var j = random.Next(i, n);
        (a[i], a[j]) = (a[j], a[i]);
    }

    if (take.HasValue) return new ArraySegment<T>(a, 0, take.Value);
    return a;
}

Android update activity UI from service

Clyde's solution works, but it is a broadcast, which I am pretty sure will be less efficient than calling a method directly. I could be mistaken, but I think the broadcasts are meant more for inter-application communication.

I'm assuming you already know how to bind a service with an Activity. I do something sort of like the code below to handle this kind of problem:

class MyService extends Service {
    MyFragment mMyFragment = null;
    MyFragment mMyOtherFragment = null;

    private void networkLoop() {
        ...

        //received new data for list.
        if(myFragment != null)
            myFragment.updateList();
        }

        ...

        //received new data for textView
        if(myFragment !=null)
            myFragment.updateText();

        ...

        //received new data for textView
        if(myOtherFragment !=null)
            myOtherFragment.updateSomething();

        ...
    }
}


class MyFragment extends Fragment {

    public void onResume() {
        super.onResume()
        //Assuming your activity bound to your service
        getActivity().mMyService.mMyFragment=this;
    }

    public void onPause() {
        super.onPause()
        //Assuming your activity bound to your service
        getActivity().mMyService.mMyFragment=null;
    }

    public void updateList() {
        runOnUiThread(new Runnable() {
            public void run() {
                //Update the list.
            }
        });
    }

    public void updateText() {
       //as above
    }
}

class MyOtherFragment extends Fragment {
             public void onResume() {
        super.onResume()
        //Assuming your activity bound to your service
        getActivity().mMyService.mMyOtherFragment=this;
    }

    public void onPause() {
        super.onPause()
        //Assuming your activity bound to your service
        getActivity().mMyService.mMyOtherFragment=null;
    }

    public void updateSomething() {//etc... }
}

I left out bits for thread safety, which is essential. Make sure to use locks or something like that when checking and using or changing the fragment references on the service.

How can I scale the content of an iframe?

If you want the iframe and its contents to scale when the window resizes, you can set the following to the window's resize event as well as the iframes onload event.

function()
{
    var _wrapWidth=$('#wrap').width();
    var _frameWidth=$($('#frame')[0].contentDocument).width();

    if(!this.contentLoaded)
      this.initialWidth=_frameWidth;
    this.contentLoaded=true;
    var frame=$('#frame')[0];

    var percent=_wrapWidth/this.initialWidth;

    frame.style.width=100.0/percent+"%";
    frame.style.height=100.0/percent+"%";

    frame.style.zoom=percent;
    frame.style.webkitTransform='scale('+percent+')';
    frame.style.webkitTransformOrigin='top left';
    frame.style.MozTransform='scale('+percent+')';
    frame.style.MozTransformOrigin='top left';
    frame.style.oTransform='scale('+percent+')';
    frame.style.oTransformOrigin='top left';
  };

This will make the iframe and its content scale to 100% width of the wrap div (or whatever percent you want). As an added bonus, you don't have to set the css of the frame to hard coded values since they'll all be set dynamically, you'll just need to worry about how you want the wrap div to display.

I've tested this and it works on chrome, IE11, and firefox.

How do I display a text file content in CMD?

If you want it to display the content of the file live, and update when the file is altered, just use this script:

@echo off
:start
cls
type myfile.txt
goto start

That will repeat forever until you close the cmd window.

What are the best practices for using a GUID as a primary key, specifically regarding performance?

This link says it better than I could and helped in my decision making. I usually opt for an int as a primary key, unless I have a specific need not to and I also let SQL server auto-generate/maintain this field unless I have some specific reason not to. In reality, performance concerns need to be determined based on your specific app. There are many factors at play here including but not limited to expected db size, proper indexing, efficient querying, and more. Although people may disagree, I think in many scenarios you will not notice a difference with either option and you should choose what is more appropriate for your app and what allows you to develop easier, quicker, and more effectively (If you never complete the app what difference does the rest make :).

https://web.archive.org/web/20120812080710/http://databases.aspfaq.com/database/what-should-i-choose-for-my-primary-key.html

P.S. I'm not sure why you would use a Composite PK or what benefit you believe that would give you.

How to link to part of the same document in Markdown?

Using kramdown, it seems like this works well:

[I want this to link to foo](#foo)
....
....
{: id="foo"}
### Foo are you?

I see it's been mentioned that

[foo][#foo]
....
#Foo

works efficiently, but the former might be a good alternative for elements besides headers or else headers with multiple words.

How to properly seed random number generator

Small update due to golang api change, please omit .UTC() :

time.Now().UTC().UnixNano() -> time.Now().UnixNano()

import (
    "fmt"
    "math/rand"
    "time"
)

func main() {
    rand.Seed(time.Now().UnixNano())
    fmt.Println(randomInt(100, 1000))
}

func randInt(min int, max int) int {
    return min + rand.Intn(max-min)
}

toggle show/hide div with button?

Pure JavaScript:

var button = document.getElementById('button'); // Assumes element with id='button'

button.onclick = function() {
    var div = document.getElementById('newpost');
    if (div.style.display !== 'none') {
        div.style.display = 'none';
    }
    else {
        div.style.display = 'block';
    }
};

SEE DEMO

jQuery:

$("#button").click(function() { 
    // assumes element with id='button'
    $("#newpost").toggle();
});

SEE DEMO

How do I store the select column in a variable?

This is how to assign a value to a variable:

SELECT @EmpID = Id
  FROM dbo.Employee

However, the above query is returning more than one value. You'll need to add a WHERE clause in order to return a single Id value.

Creating a Plot Window of a Particular Size

A convenient function for saving plots is ggsave(), which can automatically guess the device type based on the file extension, and smooths over differences between devices. You save with a certain size and units like this:

ggsave("mtcars.png", width = 20, height = 20, units = "cm")

In R markdown, figure size can be specified by chunk:

```{r, fig.width=6, fig.height=4}  
plot(1:5)
```

What's better at freeing memory with PHP: unset() or $var = null

By doing an unset() on a variable, you've essentially marked the variable for 'garbage collection' (PHP doesn't really have one, but for example's sake) so the memory isn't immediately available. The variable no longer houses the data, but the stack remains at the larger size. Doing the null method drops the data and shrinks the stack memory almost immediately.

This has been from personal experience and others as well. See the comments of the unset() function here.

I personally use unset() between iterations in a loop so that I don't have to have the delay of the stack being yo-yo'd in size. The data is gone, but the footprint remains. On the next iteration, the memory is already being taken by php and thus, quicker to initialize the next variable.

Correctly determine if date string is a valid date in that format

You can use DateTime::createFromFormat() for this purpose:

function validateDate($date, $format = 'Y-m-d')
{
    $d = DateTime::createFromFormat($format, $date);
    // The Y ( 4 digits year ) returns TRUE for any integer with any number of digits so changing the comparison from == to === fixes the issue.
    return $d && $d->format($format) === $date;
}

[Function taken from this answer. Also on php.net. Originally written by Glavic.]


Test cases:

var_dump(validateDate('2013-13-01'));  // false
var_dump(validateDate('20132-13-01')); // false
var_dump(validateDate('2013-11-32'));  // false
var_dump(validateDate('2012-2-25'));   // false
var_dump(validateDate('2013-12-01'));  // true
var_dump(validateDate('1970-12-01'));  // true
var_dump(validateDate('2012-02-29'));  // true
var_dump(validateDate('2012', 'Y'));   // true
var_dump(validateDate('12012', 'Y'));  // false

Demo!

MYSQL import data from csv using LOAD DATA INFILE

Insert bulk more than 7000000 record in 1 minutes in database(superfast query with calculation)

mysqli_query($cons, '
    LOAD DATA LOCAL INFILE "'.$file.'"
    INTO TABLE tablename
    FIELDS TERMINATED by \',\'
    LINES TERMINATED BY \'\n\'
    IGNORE 1 LINES
    (isbn10,isbn13,price,discount,free_stock,report,report_date)
     SET RRP = IF(discount = 0.00,price-price * 45/100,IF(discount = 0.01,price,IF(discount != 0.00,price-price * discount/100,@RRP))),
         RRP_nl = RRP * 1.44 + 8,
         RRP_bl = RRP * 1.44 + 8,
         ID = NULL
    ');
$affected = (int) (mysqli_affected_rows($cons))-1; 
$log->lwrite('Inventory.CSV to database:'. $affected.' record inserted successfully.');

RRP and RRP_nl and RRP_bl is not in csv but we are calculated that and after insert that.

How to find the mime type of a file in python?

you can use imghdr Python module.

How to re-index all subarray elements of a multidimensional array?

Use array_values to reset keys

foreach($input as &$val) {
   $val = array_values($val);
}

http://php.net/array_values

How does the JPA @SequenceGenerator annotation work

I have MySQL schema with autogen values. I use strategy=GenerationType.IDENTITY tag and seems to work fine in MySQL I guess it should work most db engines as well.

CREATE TABLE user (
    id bigint NOT NULL auto_increment,
    name varchar(64) NOT NULL default '',
    PRIMARY KEY (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

User.java:

// mark this JavaBean to be JPA scoped class
@Entity
@Table(name="user")
public class User {
    @Id @GeneratedValue(strategy=GenerationType.IDENTITY)
    private long id;    // primary key (autogen surrogate)

    @Column(name="name")
    private String name;

    public long getId() { return id; }
    public void setId(long id) { this.id = id; }

    public String getName() { return name; }
    public void setName(String name) { this.name=name; }
}

Why am I suddenly getting a "Blocked loading mixed active content" issue in Firefox?

In absence of a white-list feature you have to make the "all" or "nothing" Choice. You can disable mixed content blocking completely.


The Nothing Choice

You will need to permanently disable mixed content blocking for the current active profile.

In the "Awesome Bar," type "about:config". If this is your first time you will get the "This might void your warranty!" message.

Yes you will be careful. Yes you promise!

Find security.mixed_content.block_active_content. Set its value to false.


The All Choice

iDevelApp's answer is awesome.

How can I read Chrome Cache files?

I've made short stupid script which extracts JPG and PNG files:

#!/usr/bin/php
<?php
 $dir="/home/user/.cache/chromium/Default/Cache/";//Chrome or chromium cache folder. 
 $ppl="/home/user/Desktop/temporary/"; // Place for extracted files 

 $list=scandir($dir);
 foreach ($list as $filename)
 {

 if (is_file($dir.$filename))
    {
        $cont=file_get_contents($dir.$filename);
        if  (strstr($cont,'JFIF'))
        {
            echo ($filename."  JPEG \n");
            $start=(strpos($cont,"JFIF",0)-6);
            $end=strpos($cont,"HTTP/1.1 200 OK",0);
            $cont=substr($cont,$start,$end-6);
            $wholename=$ppl.$filename.".jpg";
            file_put_contents($wholename,$cont);
            echo("Saving :".$wholename." \n" );


                }
        elseif  (strstr($cont,"\211PNG"))
        {
            echo ($filename."  PNG \n");
            $start=(strpos($cont,"PNG",0)-1);
            $end=strpos($cont,"HTTP/1.1 200 OK",0);
            $cont=substr($cont,$start,$end-1);
            $wholename=$ppl.$filename.".png";
            file_put_contents($wholename,$cont);
            echo("Saving :".$wholename." \n" );


                }
        else
        {
            echo ($filename."  UNKNOWN \n");
        }
    }
 }
?>

Error : ORA-01704: string literal too long

INSERT INTO table(clob_column) SELECT TO_CLOB(q'[chunk1]') || TO_CLOB(q'[chunk2]') ||
            TO_CLOB(q'[chunk3]') || TO_CLOB(q'[chunk4]') FROM DUAL;

How can I make text appear on next line instead of overflowing?

Try the <wbr> tag - not as elegant as the word-wrap property that others suggested, but it's a working solution until all major browsers (read IE) implement CSS3.

How to exit an if clause

Effectively what you're describing are goto statements, which are generally panned pretty heavily. Your second example is far easier to understand.

However, cleaner still would be:

if some_condition:
   ...
   if condition_a:
       your_function1()
   else:
       your_function2()

...

def your_function2():
   if condition_b:
       # do something
       # and then exit the outer if block
   else:
       # more code here

adding classpath in linux

Paths under linux are separated by colons (:), not semi-colons (;), as theatrus correctly used it in his example. I believe Java respects this convention.

Edit

Alternatively to what andy suggested, you may use the following form (which sets CLASSPATH for the duration of the command):

CLASSPATH=".:../somejar.jar:../mysql-connector-java-5.1.6-bin.jar" java -Xmx500m ...

whichever is more convenient to you.

How to Apply global font to whole HTML document

Use the following css:

* {
    font: Verdana, Arial, 'sans-serif' !important;/* <-- fonts */
}

The *-selector means any/all elements, but will obviously be on the bottom of the food chain when it comes to overriding more specific selectors.

Note that the !important-flag will render the font-style for * to be absolute, even if other selectors have been used to set the text (for example, the body or maybe a p).

Send HTTP POST message in ASP.NET Core using HttpClient PostAsJsonAsync

I would add to the accepted answer that you would also want to add the Accept header to the httpClient:

httpClient.DefaultRequestHeaders.Accept.Clear();
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

How to increase the gap between text and underlining in CSS

If you want:

  • multiline
  • dotted
  • with custom bottom padding
  • without wrappers

underline, you can use 1 pixel height background image with repeat-x and 100% 100% position:

display: inline;
background: url('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAIAAAABCAYAAAD0In+KAAAAEUlEQVQIW2M0Lvz//2w/IyMAFJoEAis2CPEAAAAASUVORK5CYII=') repeat-x 100% 100%;

You can replace the second 100% by something else like px or em to adjust the vertical position of the underline. Also you can use calc if you want to add vertical padding, e.g.:

padding-bottom: 5px;
background-position-y: calc(100% - 5px);

Of course you can also make your own base64 png pattern with another color, height and design, e.g. here: http://www.patternify.com/ - just set square width & height at 2x1.

Source of inspiration: http://alistapart.com/article/customunderlines

Does Java support structs?

Yes, Java doesn't have struct/value type yet. But, in the upcoming version of Java, we are going to get inline class which is similar to struct in C# and will help us write allocation free code.


inline class point { 
  int x;
  int y;
}

git clone error: RPC failed; curl 56 OpenSSL SSL_read: SSL_ERROR_SYSCALL, errno 10054

What I did is moved the dependencies list to the end of

#Pods for <app>

In Podfile. Like this:

    # Uncomment the next line to define a global platform for your project
    # platform :ios, '9.0'

    target '<app>' do
    # Comment the next line if you don't want to use dynamic frameworks
    use_frameworks!

  # Pods for <app>

  target '<app>Tests' do
    inherit! :search_paths
    # Pods for testing
  end

  target '<app>UITests' do
    inherit! :search_paths
    # Pods for testing
  end

    pod 'Firebase/Core'
    pod 'Firebase/Database'

end

Is there an XSL "contains" directive?

Use the standard XPath function contains().

Function: boolean contains(string, string)

The contains function returns true if the first argument string contains the second argument string, and otherwise returns false

Dynamically Fill Jenkins Choice Parameter With Git Branches In a Specified Repo

I tried a couple of answers mentioned in this link, but couldn't figure out how to tell Jenkins about the user-selected branch. As mentioned in my previous comment in above thread, I had left the branch selector field empty.

But, during further investigations, I found another way to do the same thing - https://wiki.jenkins-ci.org/display/JENKINS/Git+Parameter+Plugin I found this method was a lot simpler, and had less things to configure!

Here's what I configured -

  1. Installed the git parameter plugin
  2. Checked the 'This build is parameterized' and added a 'Git parameter'
  3. Added the following values: Git Parameter plugin config in the job

  4. Then in the git SCM section of the job I added the same value mentioned in the 'Name' section, as if it were an environment variable. (If you read the help for this git parameter plugin carefully, you will realize this) Branch Selector

After this I just ran the build, chose my branch(Jenkins checks out this branch before building) and it completed the build successfully, AND by choosing the branch that I had specified.

How to find out if an item is present in a std::vector?

template <typename T> bool IsInVector(const T & what, const std::vector<T> & vec)
{
    return std::find(vec.begin(),vec.end(),what)!=vec.end();
}

Get clicked element using jQuery on event?

You are missing the event parameter on your function.

$(document).on("click",".appDetails", function (event) {
    alert(event.target.id);
});

Add shadow to custom shape on Android

This question may be old, but for anybody in future that wants a simple way to achieve complex shadow effects check out my library here https://github.com/BluRe-CN/ComplexView

Using the library, you can change shadow colors, tweak edges and so much more. Here's an example to achieve what you seek for.

<com.blure.complexview.ComplexView
        android:layout_width="400dp"
        android:layout_height="600dp"
        app:radius="10dp"
        app:shadow="true"
        app:shadowSpread="2">

        <com.blure.complexview.ComplexView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:color="#fdfcfc"
            app:radius="10dp" />
    </com.blure.complexview.ComplexView>

To change the shadow color, use app:shadowColor="your color code".

Interface extends another interface but implements its methods

An interface defines behavior. For example, a Vehicle interface might define the move() method.

A Car is a Vehicle, but has additional behavior. For example, the Car interface might define the startEngine() method. Since a Car is also a Vehicle, the Car interface extends the Vehicle interface, and thus defines two methods: move() (inherited) and startEngine().

The Car interface doesn't have any method implementation. If you create a class (Volkswagen) that implements Car, it will have to provide implementations for all the methods of its interface: move() and startEngine().

An interface may not implement any other interface. It can only extend it.

How can I switch to a tag/branch in hg?

Once you have cloned the repo, you have everything: you can then hg up branchname or hg up tagname to update your working copy.

UP: hg up is a shortcut of hg update, which also has hg checkout alias for people with git habits.

Set cookie and get cookie with JavaScript

I find the following code to be much simpler than anything else:

function setCookie(name,value,days) {
    var expires = "";
    if (days) {
        var date = new Date();
        date.setTime(date.getTime() + (days*24*60*60*1000));
        expires = "; expires=" + date.toUTCString();
    }
    document.cookie = name + "=" + (value || "")  + expires + "; path=/";
}
function getCookie(name) {
    var nameEQ = name + "=";
    var ca = document.cookie.split(';');
    for(var i=0;i < ca.length;i++) {
        var c = ca[i];
        while (c.charAt(0)==' ') c = c.substring(1,c.length);
        if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
    }
    return null;
}
function eraseCookie(name) {   
    document.cookie = name +'=; Path=/; Expires=Thu, 01 Jan 1970 00:00:01 GMT;';
}

Now, calling functions

setCookie('ppkcookie','testcookie',7);

var x = getCookie('ppkcookie');
if (x) {
    [do something with x]
}

Source - http://www.quirksmode.org/js/cookies.html

They updated the page today so everything in the page should be latest as of now.

Twitter Bootstrap Form File Element Upload Button

http://markusslima.github.io/bootstrap-filestyle/

$(":file").filestyle();

OR

<input type="file" class="filestyle" data-input="false">

Select all contents of textbox when it receives focus (Vanilla JS or jQuery)

_x000D_
_x000D_
<input type="text" onfocus="this.select();" onmouseup="return false;" value="test" />
_x000D_
_x000D_
_x000D_

Accessing session from TWIG template

Setup twig

$twig = new Twig_Environment(...);    
$twig->addGlobal('session', $_SESSION);

Then within your template access session values for example

$_SESSION['username'] in php file Will be equivalent to {{ session.username }} in your twig template

PowerShell Connect to FTP server and get files

The remotePickupDir would be the folder you want to go to on the ftp server. As far as "is this script correct", well, does it work? If it works then it's correct. If it does not work, then tell us what error message or unexpected behaviour you're getting and we'll be better able to help you.

Overlapping Views in Android

If you want to add you custom Overlay screen on Layout, you can create a Custom Linear Layout and get control of drawing and key events. You can my tutorial- Overlay on Android Layout- http://prasanta-paul.blogspot.com/2010/08/overlay-on-android-layout.html

Change font-weight of FontAwesome icons?

Just to help anyone coming to this page. This is an alternate if you are flexible with using some other icon library.

James is correct that you cannot change the font weight however if you are looking for more modern look for icons then you might consider ionicons

It has both ios and android versions for icons.

Removing double quotes from a string in Java

You can just go for String replace method.-

line1 = line1.replace("\"", "");

jQuery: select all elements of a given class, except for a particular Id

Using the .not() method with selecting an entire element is also an option.

This way could be usefull if you want to do another action with that element directly.

$(".thisClass").not($("#thisId")[0].doAnotherAction()).doAction();

Get decimal portion of a number with JavaScript

Although I am very late to answer this, please have a look at the code.

let floatValue = 3.267848;
let decimalDigits = floatValue.toString().split('.')[1];
let decimalPlaces = decimalDigits.length;
let decimalDivider = Math.pow(10, decimalPlaces);
let fractionValue = decimalDigits/decimalDivider;
let integerValue = floatValue - fractionValue;

console.log("Float value: "+floatValue);
console.log("Integer value: "+integerValue);
console.log("Fraction value: "+fractionValue)

Detect when an HTML5 video finishes

Have a look at this Everything You Need to Know About HTML5 Video and Audio post at the Opera Dev site under the "I want to roll my own controls" section.

This is the pertinent section:

<video src="video.ogv">
     video not supported
</video>

then you can use:

<script>
    var video = document.getElementsByTagName('video')[0];

    video.onended = function(e) {
      /*Do things here!*/
    };
</script>

onended is a HTML5 standard event on all media elements, see the HTML5 media element (video/audio) events documentation.

How to format numbers?

Or you could use the sugar.js library, and the format method:

format( place = 0 , thousands = ',' , decimal = '.' ) Formats the number to a readable string. If place is undefined, will automatically determine the place. thousands is the character used for the thousands separator. decimal is the character used for the decimal point.

Examples:

(56782).format() > "56,782"
(56782).format(2) > "56,782.00"
(4388.43).format(2, ' ') > "4 388.43"
(4388.43).format(3, '.', ',') > "4.388,430"