Programs & Examples On #Telnetlib

The telnetlib module provides a Telnet class that implements the Telnet protocol under Python programming language.

Docker "ERROR: could not find an available, non-overlapping IPv4 address pool among the defaults to assign to the network"

Killing the vpn is not needed.

This other comment about using a new network comes pretty close to the solution for me, and was working for a while, but I found a better way thanks to some talk over in another question

Create a network with:

docker network create your-network --subnet 172.24.24.0/24

Then, at the bottom of docker-compose.yaml, put this:

networks:
  default:
    external: 
      name: your-network

Done. No need to add networks to all container definitions etc. and you can re-use the network with other docker-compose files as well if you'd like.

What does "\r" do in the following script?

The '\r' character is the carriage return, and the carriage return-newline pair is both needed for newline in a network virtual terminal session.


From the old telnet specification (RFC 854) (page 11):

The sequence "CR LF", as defined, will cause the NVT to be positioned at the left margin of the next print line (as would, for example, the sequence "LF CR").

However, from the latest specification (RFC5198) (page 13):

  1. ...

  2. In Net-ASCII, CR MUST NOT appear except when immediately followed by either NUL or LF, with the latter (CR LF) designating the "new line" function. Today and as specified above, CR should generally appear only when followed by LF. Because page layout is better done in other ways, because NUL has a special interpretation in some programming languages, and to avoid other types of confusion, CR NUL should preferably be avoided as specified above.

  3. LF CR SHOULD NOT appear except as a side-effect of multiple CR LF sequences (e.g., CR LF CR LF).

So newline in Telnet should always be '\r\n' but most implementations have either not been updated, or keeps the old '\n\r' for backwards compatibility.

SQL Delete Records within a specific Range

if you use Sql Server

delete from Table where id between 79 and 296

After your edit : you now clarified that you want :

ID (>79 AND < 296)

So use this :

delete from Table where id > 79 and id < 296

How to store file name in database, with other info while uploading image to server using PHP?

If you want to input more data into the form, you simply access the submitted data through $_POST.

If you have

<input type="text" name="firstname" />

you access it with

$firstname = $_POST["firstname"];

You could then update your query line to read

mysql_query("INSERT INTO dbProfiles (photo,firstname)
             VALUES('{$filename}','{$firstname}')");

Note: Always filter and sanitize your data.

Raise an event whenever a property's value changed?

Raising an event when a property changes is precisely what INotifyPropertyChanged does. There's one required member to implement INotifyPropertyChanged and that is the PropertyChanged event. Anything you implemented yourself would probably be identical to that implementation, so there's no advantage to not using it.

When does Git refresh the list of remote branches?

To update the local list of remote branches:

git remote update origin --prune

To show all local and remote branches that (local) Git knows about

git branch -a

"Please provide a valid cache path" error in laravel

Try the following:

create these folders under storage/framework:

  • sessions
  • views
  • cache

Now it should work

Chrome doesn't delete session cookies

This maybe because Chrome is still running in background after you close the browser. Try to disable this feature by doing following:

  1. Open chrome://settings/
  2. Click "Show advanced settings ..."
  3. Navigate down to System section and disable "Continue running background apps when Google Chrome is closed". This will force Chrome to close completely and then it will delete session cookies.

However, I think Chrome should check and delete previous session cookies at it starting instead of closing.

HashMap to return default value for non-found keys?

In Java 8, use Map.getOrDefault. It takes the key, and the value to return if no matching key is found.

How do I check if a file exists in Java?

You can make it this way

import java.nio.file.Paths;

String file = "myfile.sss";
if(Paths.get(file).toFile().isFile()){
    //...do somethinh
}

How do I keep Python print from adding newlines or spaces?

import sys

sys.stdout.write('h')
sys.stdout.flush()

sys.stdout.write('m')
sys.stdout.flush()

You need to call sys.stdout.flush() because otherwise it will hold the text in a buffer and you won't see it.

Simplest way to merge ES6 Maps/Sets?

No, there are no builtin operations for these, but you can easily create them your own:

Map.prototype.assign = function(...maps) {
    for (const m of maps)
        for (const kv of m)
            this.add(...kv);
    return this;
};

Set.prototype.concat = function(...sets) {
    const c = this.constructor;
    let res = new (c[Symbol.species] || c)();
    for (const set of [this, ...sets])
        for (const v of set)
            res.add(v);
    return res;
};

Android SQLite SELECT Query

Try trimming the string to make sure there is no extra white space:

Cursor c = db.rawQuery("SELECT * FROM tbl1 WHERE TRIM(name) = '"+name.trim()+"'", null);

Also use c.moveToFirst() like @thinksteep mentioned.


This is a complete code for select statements.

SQLiteDatabase db = this.getReadableDatabase();
Cursor c = db.rawQuery("SELECT column1,column2,column3 FROM table ", null);
if (c.moveToFirst()){
    do {
        // Passing values 
        String column1 = c.getString(0);
        String column2 = c.getString(1);
        String column3 = c.getString(2); 
        // Do something Here with values
    } while(c.moveToNext());
}
c.close();
db.close();

Getting "unixtime" in Java

Java 8 added a new API for working with dates and times. With Java 8 you can use

import java.time.Instant
...
long unixTimestamp = Instant.now().getEpochSecond();

Instant.now() returns an Instant that represents the current system time. With getEpochSecond() you get the epoch seconds (unix time) from the Instant.

Get Android Device Name

Simply use

BluetoothAdapter.getDefaultAdapter().getName()

.Net HttpWebRequest.GetResponse() raises exception when http status code 400 (bad request) is returned

I had similar issues when trying to connect to Google's OAuth2 service.

I ended up writing the POST manually, not using WebRequest, like this:

TcpClient client = new TcpClient("accounts.google.com", 443);
Stream netStream = client.GetStream();
SslStream sslStream = new SslStream(netStream);
sslStream.AuthenticateAsClient("accounts.google.com");

{
    byte[] contentAsBytes = Encoding.ASCII.GetBytes(content.ToString());

    StringBuilder msg = new StringBuilder();
    msg.AppendLine("POST /o/oauth2/token HTTP/1.1");
    msg.AppendLine("Host: accounts.google.com");
    msg.AppendLine("Content-Type: application/x-www-form-urlencoded");
    msg.AppendLine("Content-Length: " + contentAsBytes.Length.ToString());
    msg.AppendLine("");
    Debug.WriteLine("Request");
    Debug.WriteLine(msg.ToString());
    Debug.WriteLine(content.ToString());

    byte[] headerAsBytes = Encoding.ASCII.GetBytes(msg.ToString());
    sslStream.Write(headerAsBytes);
    sslStream.Write(contentAsBytes);
}

Debug.WriteLine("Response");

StreamReader reader = new StreamReader(sslStream);
while (true)
{  // Print the response line by line to the debug stream for inspection.
    string line = reader.ReadLine();
    if (line == null) break;
    Debug.WriteLine(line);
}

The response that gets written to the response stream contains the specific error text that you're after.

In particular, my problem was that I was putting endlines between url-encoded data pieces. When I took them out, everything worked. You might be able to use a similar technique to connect to your service and read the actual response error text.

How to get a path to the desktop for current user in C#?

 string filePath = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
 string extension = ".log";
 filePath += @"\Error Log\" + extension;
 if (!Directory.Exists(filePath))
 {
      Directory.CreateDirectory(filePath);
 }

HTML set image on browser tab

It's called a Favicon, have a read.

<link rel="shortcut icon" href="http://www.example.com/myicon.ico"/>

You can use this neat tool to generate cross-browser compatible Favicons.

Python pandas: fill a dataframe row by row

My approach was, but I can't guarantee that this is the fastest solution.

df = pd.DataFrame(columns=["firstname", "lastname"])
df = df.append({
     "firstname": "John",
     "lastname":  "Johny"
      }, ignore_index=True)

How to get the difference (only additions) between two files in linux

All of the below is copied directly from @TomOnTime's serverfault answer here:

Show lines that only exist in file a: (i.e. what was deleted from a)

comm -23 a b

Show lines that only exist in file b: (i.e. what was added to b)

comm -13 a b

Show lines that only exist in one file or the other: (but not both)

comm -3 a b | sed 's/^\t//'

(Warning: If file a has lines that start with TAB, it (the first TAB) will be removed from the output.)

NOTE: Both files need to be sorted for "comm" to work properly. If they aren't already sorted, you should sort them:

sort <a >a.sorted
sort <b >b.sorted
comm -12 a.sorted b.sorted

If the files are extremely long, this may be quite a burden as it requires an extra copy and therefore twice as much disk space.

Edit: note that the command can be written more concisely using process substitution (thanks to @phk for the comment):

comm -12 <(sort < a) <(sort < b)

Getting Keyboard Input

You can use Scanner class

To Read from Keyboard (Standard Input) You can use Scanner is a class in java.util package.

Scanner package used for obtaining the input of the primitive types like int, double etc. and strings. It is the easiest way to read input in a Java program, though not very efficient.

  1. To create an object of Scanner class, we usually pass the predefined object System.in, which represents the standard input stream (Keyboard).

For example, this code allows a user to read a number from System.in:

Scanner sc = new Scanner(System.in);
     int i = sc.nextInt();

Some Public methods in Scanner class.

  • hasNext() Returns true if this scanner has another token in its input.
  • nextInt() Scans the next token of the input as an int.
  • nextFloat() Scans the next token of the input as a float.
  • nextLine() Advances this scanner past the current line and returns the input that was skipped.
  • nextDouble() Scans the next token of the input as a double.
  • close() Closes this scanner.

For more details of Public methods in Scanner class.

Example:-

import java.util.Scanner;                      //importing class

class ScannerTest {
  public static void main(String args[]) {
    Scanner sc = new Scanner(System.in);       // Scanner object

    System.out.println("Enter your rollno");
    int rollno = sc.nextInt();
    System.out.println("Enter your name");
    String name = sc.next();
    System.out.println("Enter your fee");
    double fee = sc.nextDouble();
    System.out.println("Rollno:" + rollno + " name:" + name + " fee:" + fee);
    sc.close();                              // closing object
  }
}

How do I apply a diff patch on Windows?

If you are using Mercurial, this is done via "import". So at the command line, the hg import command, or (you may find the --no-commit option useful), or "Repository" => "Import..." in Hg Workbench.

Note that these will commit the changes by default; you can avoid this using hg import --no-commit option if using the command-line, or if you used Hg Workbench, you might find it useful to issue hg rollback after the merge.

Use of *args and **kwargs

One case where *args and **kwargs are useful is when writing wrapper functions (such as decorators) that need to be able accept arbitrary arguments to pass through to the function being wrapped. For example, a simple decorator that prints the arguments and return value of the function being wrapped:

def mydecorator( f ):
   @functools.wraps( f )
   def wrapper( *args, **kwargs ):
      print "Calling f", args, kwargs
      v = f( *args, **kwargs )
      print "f returned", v
      return v
   return wrapper

Typescript Date Type?

The answer is super simple, the type is Date:

const d: Date = new Date(); // but the type can also be inferred from "new Date()" already

It is the same as with every other object instance :)

Add a prefix string to beginning of each line

If your prefix is a bit complicated, just put it in a variable:

prefix=path/to/file/

Then, you pass that variable and let awk deal with it:

awk -v prefix="$prefix" '{print prefix $0}' input_file.txt

linux execute command remotely

I guess ssh is the best secured way for this, for example :

ssh -OPTIONS -p SSH_PORT user@remote_server "remote_command1; remote_command2; remote_script.sh"  

where the OPTIONS have to be deployed according to your specific needs (for example, binding to ipv4 only) and your remote command could be starting your tomcat daemon.

Note:
If you do not want to be prompt at every ssh run, please also have a look to ssh-agent, and optionally to keychain if your system allows it. Key is... to understand the ssh keys exchange process. Please take a careful look to ssh_config (i.e. the ssh client config file) and sshd_config (i.e. the ssh server config file). Configuration filenames depend on your system, anyway you'll find them somewhere like /etc/sshd_config. Ideally, pls do not run ssh as root obviously but as a specific user on both sides, servers and client.

Some extra docs over the source project main pages :

ssh and ssh-agent
man ssh

http://www.snailbook.com/index.html
https://help.ubuntu.com/community/SSH/OpenSSH/Configuring

keychain
http://www.gentoo.org/doc/en/keychain-guide.xml
an older tuto in French (by myself :-) but might be useful too :
http://hornetbzz.developpez.com/tutoriels/debian/ssh/keychain/

How to grey out a button?

Set Clickable as false and change the backgroung color as:

callButton.setClickable(false);
callButton.setBackgroundColor(Color.parseColor("#808080"));

Angular: Cannot Get /

First, delete existing files package.lock.json and node_modules from your project. Then, the first step is to write npm cache clean --force. Second, also write this command npm i on the terminal. This process resolve my error. :D

How to 'insert if not exists' in MySQL?

REPLACE INTO `transcripts`
SET `ensembl_transcript_id` = 'ENSORGT00000000001',
`transcript_chrom_start` = 12345,
`transcript_chrom_end` = 12678;

If the record exists, it will be overwritten; if it does not yet exist, it will be created.

how to fix EXE4J_JAVA_HOME, No JVM could be found on your system error?

BH's answer of installing Java 6u45 was very close... still got the popup on reboot...BUT after uninstalling Java 6u45, rebooted, no warning! Thank you BH! Then installed the latest version, 8u151-i586, rebooted no warning.

I added lines in PATH as above, didn't do anything.

My system: Windows 7, 64 bit. Warning was for No JVM, 32 bit Java not found. Yes, I could have installed the 64 bit version, but 32bit is more compatible with all programs.

How to get the selected date value while using Bootstrap Datepicker?

Try this using HTML like here:

var myDate = window.document.getElementById("startdate").value;

git add remote branch

I am not sure if you are trying to create a remote branch from a local branch or vice versa, so I've outlined both scenarios as well as provided information on merging the remote and local branches.

Creating a remote called "github":

git remote add github git://github.com/jdoe/coolapp.git
git fetch github

List all remote branches:

git branch -r
  github/gh-pages
  github/master
  github/next
  github/pu

Create a new local branch (test) from a github's remote branch (pu):

git branch test github/pu
git checkout test

Merge changes from github's remote branch (pu) with local branch (test):

git fetch github
git checkout test
git merge github/pu

Update github's remote branch (pu) from a local branch (test):

git push github test:pu

Creating a new branch on a remote uses the same syntax as updating a remote branch. For example, create new remote branch (beta) on github from local branch (test):

git push github test:beta

Delete remote branch (pu) from github:

git push github :pu

Any shortcut to initialize all array elements to zero?

You can save the loop, initialization is already made to 0. Even for a local variable.

But please correct the place where you place the brackets, for readability (recognized best-practice):

int[] arr = new int[10];

Setting java locale settings

With the user.language, user.country and user.variant properties.

Example:

java -Duser.language=th -Duser.country=TH -Duser.variant=TH SomeClass

How to use lifecycle method getDerivedStateFromProps as opposed to componentWillReceiveProps

getDerivedStateFromProps is used whenever you want to update state before render and update with the condition of props

GetDerivedStateFromPropd updating the stats value with the help of props value

read https://www.w3schools.com/REACT/react_lifecycle.asp#:~:text=Lifecycle%20of%20Components,Mounting%2C%20Updating%2C%20and%20Unmounting.

How do relative file paths work in Eclipse?

A project's build path defines which resources from your source folders are copied to your output folders. Usually this is set to Include all files.

New run configurations default to using the project directory for the working directory, though this can also be changed.

This code shows the difference between the working directory, and the location of where the class was loaded from:

public class TellMeMyWorkingDirectory {
    public static void main(String[] args) {
        System.out.println(new java.io.File("").getAbsolutePath());
        System.out.println(TellMeMyWorkingDirectory.class.getClassLoader().getResource("").getPath());
    }
}

The output is likely to be something like:

C:\your\project\directory
/C:/your/project/directory/bin/

How to import cv2 in python3?

Your screenshot shows you doing a pip install from the python terminal which is wrong. Do that outside the python terminal. Also the package I believe you want is:

pip install opencv-python

Since you're running on Windows, I might look at the official install manual: https://breakthrough.github.io/Installing-OpenCV

opencv2 is ONLY compatible with Python3 if you do so by compiling the source code. See the section under opencv supported python versions: https://pypi.org/project/opencv-python

How to call codeigniter controller function from view

One idea i can give is,

Call that function in controller itself and return value to view file. Like,

class Business extends CI_Controller {
    public function index() {
            $data['css'] = 'profile';

            $data['cur_url'] = $this->getCurrURL(); // the function called and store val
            $this->load->view("home_view",$data);
     }
     function getCurrURL() {
                $currURL='http://'.$_SERVER['HTTP_HOST'].'/'.ltrim($_SERVER['REQUEST_URI'],'/').'';
            return $currURL;
     }

}

in view(home_view.php) use that variable. Like,

echo $cur_url;

mongod command not recognized when trying to connect to a mongodb server

before using MongoDB you have to run it locally to do that:

  • go to bin folder you will find at C:\Program Files\MongoDB\Server\4.2\bin
  • open mongod.exe. will open a new terminal with server details.
  • open mongo.exe. will open the shell which allows you to interact with the database.

add onclick function to a submit button

I have this code:

_x000D_
_x000D_
<html>_x000D_
<head>_x000D_
<SCRIPT type=text/javascript>_x000D_
function deshabilitarBoton() {     _x000D_
    document.getElementById("boton").style.display = 'none';_x000D_
    document.getElementById("envio").innerHTML ="<br><img src='img/loading.gif' width='16' height='16' border='0'>Generando...";     _x000D_
    return true;_x000D_
} _x000D_
</SCRIPT>_x000D_
<title>untitled</title>_x000D_
</head>_x000D_
<body>_x000D_
<form name="form" action="ok.do" method="post" >_x000D_
<table>_x000D_
<tr>_x000D_
<td>Fecha inicio:</td>_x000D_
<td><input type="TEXT" name="fecha_inicio" id="fecha_inicio"  /></td>_x000D_
</tr>_x000D_
</table>_x000D_
<div id="boton">_x000D_
   <input type="submit" name="event" value="Enviar" class="button" onclick="return deshabilitarBoton()" />_x000D_
</div>_x000D_
<div id="envio">_x000D_
</div>_x000D_
</form>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Make Vim show ALL white spaces as a character

I didn't find exactly what I wanted from the existing answers. The code below will highlight all trailing spaces bright red. Simply add the following to your .vimrc

highlight ExtraWhitespace ctermbg=red guibg=red
match ExtraWhitespace /\s\+$/
autocmd BufWinEnter * match ExtraWhitespace /\s\+$/
autocmd InsertEnter * match ExtraWhitespace /\s\+\%#\@<!$/
autocmd InsertLeave * match ExtraWhitespace /\s\+$/
autocmd BufWinLeave * call clearmatches()

Eliminating NAs from a ggplot

Additionally, adding na.rm= TRUE to your geom_bar() will work.

ggplot(data = MyData,aes(x= the_variable, fill=the_variable, na.rm = TRUE)) + 
   geom_bar(stat="bin", na.rm = TRUE)

I ran into this issue with a loop in a time series and this fixed it. The missing data is removed and the results are otherwise uneffected.

What does <T> denote in C#

It is a generic type parameter, see Generics documentation.

T is not a reserved keyword. T, or any given name, means a type parameter. Check the following method (just as a simple example).

T GetDefault<T>()
{
    return default(T);
}

Note that the return type is T. With this method you can get the default value of any type by calling the method as:

GetDefault<int>(); // 0
GetDefault<string>(); // null
GetDefault<DateTime>(); // 01/01/0001 00:00:00
GetDefault<TimeSpan>(); // 00:00:00

.NET uses generics in collections, ... example:

List<int> integerList = new List<int>();

This way you will have a list that only accepts integers, because the class is instancited with the type T, in this case int, and the method that add elements is written as:

public class List<T> : ...
{
    public void Add(T item);
}

Some more information about generics.

You can limit the scope of the type T.

The following example only allows you to invoke the method with types that are classes:

void Foo<T>(T item) where T: class
{
}

The following example only allows you to invoke the method with types that are Circle or inherit from it.

void Foo<T>(T item) where T: Circle
{
}

And there is new() that says you can create an instance of T if it has a parameterless constructor. In the following example T will be treated as Circle, you get intellisense...

void Foo<T>(T item) where T: Circle, new()
{
    T newCircle = new T();
}

As T is a type parameter, you can get the object Type from it. With the Type you can use reflection...

void Foo<T>(T item) where T: class
{
    Type type = typeof(T);
}

As a more complex example, check the signature of ToDictionary or any other Linq method.

public static Dictionary<TKey, TSource> ToDictionary<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector);

There isn't a T, however there is TKey and TSource. It is recommended that you always name type parameters with the prefix T as shown above.

You could name TSomethingFoo if you want to.

pandas three-way joining multiple dataframes on columns

Here is a method to merge a dictionary of data frames while keeping the column names in sync with the dictionary. Also it fills in missing values if needed:

This is the function to merge a dict of data frames

def MergeDfDict(dfDict, onCols, how='outer', naFill=None):
  keys = dfDict.keys()
  for i in range(len(keys)):
    key = keys[i]
    df0 = dfDict[key]
    cols = list(df0.columns)
    valueCols = list(filter(lambda x: x not in (onCols), cols))
    df0 = df0[onCols + valueCols]
    df0.columns = onCols + [(s + '_' + key) for s in valueCols] 

    if (i == 0):
      outDf = df0
    else:
      outDf = pd.merge(outDf, df0, how=how, on=onCols)   

  if (naFill != None):
    outDf = outDf.fillna(naFill)

  return(outDf)

OK, lets generates data and test this:

def GenDf(size):
  df = pd.DataFrame({'categ1':np.random.choice(a=['a', 'b', 'c', 'd', 'e'], size=size, replace=True),
                      'categ2':np.random.choice(a=['A', 'B'], size=size, replace=True), 
                      'col1':np.random.uniform(low=0.0, high=100.0, size=size), 
                      'col2':np.random.uniform(low=0.0, high=100.0, size=size)
                      })
  df = df.sort_values(['categ2', 'categ1', 'col1', 'col2'])
  return(df)


size = 5
dfDict = {'US':GenDf(size), 'IN':GenDf(size), 'GER':GenDf(size)}   
MergeDfDict(dfDict=dfDict, onCols=['categ1', 'categ2'], how='outer', naFill=0)

How to serialize object to CSV file?

You can use gererics to work for any class

public class FileUtils<T> {
public String createReport(String filePath, List<T> t) {
    if (t.isEmpty()) {
        return null;
    }

    List<String> reportData = new ArrayList<String>();

    addDataToReport(t.get(0), reportData, 0);

    for (T k : t) {
        addDataToReport(k, reportData, 1);
    }
    return !dumpReport(filePath, reportData) ? null : filePath;
}

public static Boolean dumpReport(String filePath, List<String> lines) {
    Boolean isFileCreated = false;

    
    String[] dirs = filePath.split(File.separator);
    String baseDir = "";
    for (int i = 0; i < dirs.length - 1; i++) {
        baseDir += " " + dirs[i];
    }
    baseDir = baseDir.replace(" ", "/");
    
    File base = new File(baseDir);
    base.mkdirs();

    File file = new File(filePath);
    try {
        if (!file.exists())
            file.createNewFile();
    } catch (Exception e) {
        e.printStackTrace();
        return isFileCreated;
    }

    try (BufferedWriter writer = new BufferedWriter(
            new OutputStreamWriter(new FileOutputStream(file), System.getProperty("file.encoding")))) {
        for (String line : lines) {
            writer.write(line + System.lineSeparator());
        }
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }
    return true;
}

void addDataToReport(T t, List<String> reportData, int index) {
    String[] jsonObjectAsArray = new Gson().toJson(t).replace("{", "").replace("}", "").split(",\"");
    StringBuilder row = new StringBuilder();

    for (int i = 0; i < jsonObjectAsArray.length; i++) {
        String str = jsonObjectAsArray[i];
        str = str.replaceFirst(":", "_").split("_")[index];

        if (i == 0) {
            if (str != null) {
                row.append(str.replace("\"", ""));
            } else {
                row.append("N/A");
            }
        } else {
            if (str != null) {
                row.append(", " + str.replace("\"", ""));
            } else {
                row.append(", N/A");
            }
        }
    }
    reportData.add(row.toString());
}

How to check if an NSDictionary or NSMutableDictionary contains a key?

I like Fernandes' answer even though you ask for the obj twice.

This should also do (more or less the same as Martin's A).

id obj;

if ((obj=[dict objectForKey:@"blah"])) {
   // use obj
} else {
   // Do something else like creating the obj and add the kv pair to the dict
}

Martin's and this answer both work on iPad2 iOS 5.0.1 9A405

How to dismiss AlertDialog in android

Actually there is no any cancel() or dismiss() method from AlertDialog.Builder Class.

So Instead of AlertDialog.Builder optionDialog use AlertDialog instance.

Like,

AlertDialog optionDialog = new AlertDialog.Builder(this).create();

Now, Just call optionDialog.dismiss();

background.setOnClickListener(new OnClickListener() {
    public void onClick(View v) {
        SetBackground();
        // here I want to dismiss it after SetBackground() method 
        optionDialog.dismiss();
    }
});

How to Delete Session Cookie?

There are known issues with IE and Opera not removing session cookies when setting the expire date to the past (which is what the jQuery cookie plugin does)

This works fine in Safari and Mozilla/FireFox.

Adding 1 hour to time variable

$time = '10:09';
$timestamp = strtotime($time);
$timestamp_one_hour_later = $timestamp + 3600; // 3600 sec. = 1 hour

// Formats the timestamp to HH:MM => outputs 11:09.
echo strftime('%H:%M', $timestamp_one_hour_later);
// As crolpa suggested, you can also do
// echo date('H:i', $timestamp_one_hour_later);

Check PHP manual for strtotime(), strftime() and date() for details.

BTW, in your initial code, you need to add some quotes otherwise you will get PHP syntax errors:

$time = 10:09; // wrong syntax
$time = '10:09'; // syntax OK

$time = date(H:i, strtotime('+1 hour')); // wrong syntax
$time = date('H:i', strtotime('+1 hour')); // syntax OK

commons httpclient - Adding query string parameters to GET/POST request

If you want to add a query parameter after you have created the request, try casting the HttpRequest to a HttpBaseRequest. Then you can change the URI of the casted request:

HttpGet someHttpGet = new HttpGet("http://google.de");

URI uri = new URIBuilder(someHttpGet.getURI()).addParameter("q",
        "That was easy!").build();

((HttpRequestBase) someHttpGet).setURI(uri);

Base64 encoding and decoding in oracle

Solution with utl_encode.base64_encode and utl_encode.base64_decode have one limitation, they work only with strings up to 32,767 characters/bytes.

In case you have to convert bigger strings you will face several obstacles.

  • For BASE64_ENCODE the function has to read 3 Bytes and transform them. In case of Multi-Byte characters (e.g. öäüè€ stored at UTF-8, aka AL32UTF8) 3 Character are not necessarily also 3 Bytes. In order to read always 3 Bytes you have to convert your CLOB into BLOB first.
  • The same problem applies for BASE64_DECODE. The function has to read 4 Bytes and transform them into 3 Bytes. Those 3 Bytes are not necessarily also 3 Characters
  • Typically a BASE64-String has NEW_LINE (CR and/or LF) character each 64 characters. Such new-line characters have to be ignored while decoding.

Taking all this into consideration the full featured solution could be this one:

CREATE OR REPLACE FUNCTION DecodeBASE64(InBase64Char IN OUT NOCOPY CLOB) RETURN CLOB IS

    blob_loc BLOB;
    clob_trim CLOB;
    res CLOB;

    lang_context INTEGER := DBMS_LOB.DEFAULT_LANG_CTX;
    dest_offset INTEGER := 1;
    src_offset INTEGER := 1;
    read_offset INTEGER := 1;
    warning INTEGER;
    ClobLen INTEGER := DBMS_LOB.GETLENGTH(InBase64Char);

    amount INTEGER := 1440; -- must be a whole multiple of 4
    buffer RAW(1440);
    stringBuffer VARCHAR2(1440);
    -- BASE64 characters are always simple ASCII. Thus you get never any Mulit-Byte character and having the same size as 'amount' is sufficient

BEGIN

    IF InBase64Char IS NULL OR NVL(ClobLen, 0) = 0 THEN 
        RETURN NULL;
    ELSIF ClobLen<= 32000 THEN
        RETURN UTL_RAW.CAST_TO_VARCHAR2(UTL_ENCODE.BASE64_DECODE(UTL_RAW.CAST_TO_RAW(InBase64Char)));
    END IF;        
    -- UTL_ENCODE.BASE64_DECODE is limited to 32k, process in chunks if bigger    

    -- Remove all NEW_LINE from base64 string
    ClobLen := DBMS_LOB.GETLENGTH(InBase64Char);
    DBMS_LOB.CREATETEMPORARY(clob_trim, TRUE);
    LOOP
        EXIT WHEN read_offset > ClobLen;
        stringBuffer := REPLACE(REPLACE(DBMS_LOB.SUBSTR(InBase64Char, amount, read_offset), CHR(13), NULL), CHR(10), NULL);
        DBMS_LOB.WRITEAPPEND(clob_trim, LENGTH(stringBuffer), stringBuffer);
        read_offset := read_offset + amount;
    END LOOP;

    read_offset := 1;
    ClobLen := DBMS_LOB.GETLENGTH(clob_trim);
    DBMS_LOB.CREATETEMPORARY(blob_loc, TRUE);
    LOOP
        EXIT WHEN read_offset > ClobLen;
        buffer := UTL_ENCODE.BASE64_DECODE(UTL_RAW.CAST_TO_RAW(DBMS_LOB.SUBSTR(clob_trim, amount, read_offset)));
        DBMS_LOB.WRITEAPPEND(blob_loc, DBMS_LOB.GETLENGTH(buffer), buffer);
        read_offset := read_offset + amount;
    END LOOP;

    DBMS_LOB.CREATETEMPORARY(res, TRUE);
    DBMS_LOB.CONVERTTOCLOB(res, blob_loc, DBMS_LOB.LOBMAXSIZE, dest_offset, src_offset,  DBMS_LOB.DEFAULT_CSID, lang_context, warning);

    DBMS_LOB.FREETEMPORARY(blob_loc);
    DBMS_LOB.FREETEMPORARY(clob_trim);
    RETURN res;    

END DecodeBASE64;




CREATE OR REPLACE FUNCTION EncodeBASE64(InClearChar IN OUT NOCOPY CLOB) RETURN CLOB IS

    dest_lob BLOB;  
    lang_context INTEGER := DBMS_LOB.DEFAULT_LANG_CTX;
    dest_offset INTEGER := 1;
    src_offset INTEGER := 1;
    read_offset INTEGER := 1;
    warning INTEGER;
    ClobLen INTEGER := DBMS_LOB.GETLENGTH(InClearChar);

    amount INTEGER := 1440; -- must be a whole multiple of 3
    -- size of a whole multiple of 48 is beneficial to get NEW_LINE after each 64 characters 
    buffer RAW(1440);
    res CLOB := EMPTY_CLOB();

BEGIN

    IF InClearChar IS NULL OR NVL(ClobLen, 0) = 0 THEN 
        RETURN NULL;
    ELSIF ClobLen <= 24000 THEN
        RETURN UTL_RAW.CAST_TO_VARCHAR2(UTL_ENCODE.BASE64_ENCODE(UTL_RAW.CAST_TO_RAW(InClearChar)));
    END IF;
    -- UTL_ENCODE.BASE64_ENCODE is limited to 32k/(3/4), process in chunks if bigger    

    DBMS_LOB.CREATETEMPORARY(dest_lob, TRUE);
    DBMS_LOB.CONVERTTOBLOB(dest_lob, InClearChar, DBMS_LOB.LOBMAXSIZE, dest_offset, src_offset, DBMS_LOB.DEFAULT_CSID, lang_context, warning);
    LOOP
        EXIT WHEN read_offset >= dest_offset;
        DBMS_LOB.READ(dest_lob, amount, read_offset, buffer);
        res := res || UTL_RAW.CAST_TO_VARCHAR2(UTL_ENCODE.BASE64_ENCODE(buffer));       
        read_offset := read_offset + amount;
    END LOOP;
    DBMS_LOB.FREETEMPORARY(dest_lob);
    RETURN res;

END EncodeBASE64;

css with background image without repeating the image

Try this

padding:8px;
overflow: hidden;
zoom: 1;
text-align: left;
font-size: 13px;
font-family: "Trebuchet MS",Arial,Sans;
line-height: 24px;
color: black;
border-bottom: solid 1px #BBB;
background:url('images/checked.gif') white no-repeat;

This is full css.. Why you use padding:0 8px, then override it with paddings? This is what you need...

enum - getting value of enum on string conversion

I implemented access using the following

class D(Enum):
    x = 1
    y = 2

    def __str__(self):
        return '%s' % self.value

now I can just do

print(D.x) to get 1 as result.

You can also use self.name in case you wanted to print x instead of 1.

Apache Name Virtual Host with SSL

As far as I know, Apache supports SNI since Version 2.2.12 Sadly the documentation does not yet reflect that change.

Go for http://wiki.apache.org/httpd/NameBasedSSLVHostsWithSNI until that is finished

Check Postgres access for a user

You could query the table_privileges table in the information schema:

SELECT table_catalog, table_schema, table_name, privilege_type
FROM   information_schema.table_privileges 
WHERE  grantee = 'MY_USER'

Set min-width either by content or 200px (whichever is greater) together with max-width

The problem is that flex: 1 sets flex-basis: 0. Instead, you need

.container .box {
  min-width: 200px;
  max-width: 400px;
  flex-basis: auto; /* default value */
  flex-grow: 1;
}

_x000D_
_x000D_
.container {_x000D_
  display: -webkit-flex;_x000D_
  display: flex;_x000D_
  -webkit-flex-wrap: wrap;_x000D_
  flex-wrap: wrap;_x000D_
}_x000D_
_x000D_
.container .box {_x000D_
  -webkit-flex-grow: 1;_x000D_
  flex-grow: 1;_x000D_
  min-width: 100px;_x000D_
  max-width: 400px;_x000D_
  height: 200px;_x000D_
  background-color: #fafa00;_x000D_
  overflow: hidden;_x000D_
}
_x000D_
<div class="container">_x000D_
  <div class="box">_x000D_
    <table>_x000D_
      <tr>_x000D_
        <td>Content</td>_x000D_
        <td>Content</td>_x000D_
        <td>Content</td>_x000D_
      </tr>_x000D_
    </table>    _x000D_
  </div>_x000D_
  <div class="box">_x000D_
    <table>_x000D_
      <tr>_x000D_
        <td>Content</td>_x000D_
      </tr>_x000D_
    </table>    _x000D_
  </div>_x000D_
  <div class="box">_x000D_
    <table>_x000D_
      <tr>_x000D_
        <td>Content</td>_x000D_
        <td>Content</td>_x000D_
      </tr>_x000D_
    </table>    _x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to symbolicate crash log Xcode?

Apple gives you crash log in .txt format , which is unsymbolicated

**

With the device connected

**

  • Download ".txt" file , change extension to ".crash" enter image description here
    • Open devices and simulators from window tab in Xcode
    • select device and select device logs
    • drag and drop .crash file to the device log window

enter image description here

We will be able to see symbolicated crash logs over there

Please see the link for more details on Symbolicating Crash logs

Call child component method from parent class - Angular

user6779899's answer is neat and more generic However, based on the request by Imad El Hitti, a light weight solution is proposed here. This can be used when a child component is tightly connected to one parent only.

Parent.component.ts

export class Notifier {
    valueChanged: (data: number) => void = (d: number) => { };
}

export class Parent {
    notifyObj = new Notifier();
    tellChild(newValue: number) {
        this.notifyObj.valueChanged(newValue); // inform child
    }
}

Parent.component.html

<my-child-comp [notify]="notifyObj"></my-child-comp>

Child.component.ts

export class ChildComp implements OnInit{
    @Input() notify = new Notifier(); // create object to satisfy typescript
    ngOnInit(){
      this.notify.valueChanged = (d: number) => {
            console.log(`Parent has notified changes to ${d}`);
            // do something with the new value 
        };
    }
 }

Remove non-ascii character in string

To use ASCII with accents:

var str = str.replace(/[^\x00-\xFF]/g, "");

How to "git show" a merge commit with combined diff output even when every changed file agrees with one of the parents?

in your case you just need to

git diff HEAD^ HEAD^2

or just hash for you commit:

git diff 0e1329e55^ 0e1329e55^2

How to show validation message below each textbox using jquery?

This is the simple solution may work for you.

Check this solution

$('form').on('submit', function (e) {
e.preventDefault();
var emailBox=$("#email");
var passBox=$("#password");
if (!emailBox.val() || !passBox.val()) {
    $(".validationText").text("Please Enter Value").show();
}
else if(!IsEmail(emailBox.val()))
{
    emailBox.prev().text("Invalid E-mail").show();
}
$("input#email, input#password").focus(function(){
    $(this).prev(".validationText").hide();
});});

How to disable registration new users in Laravel

As of Laravel 5.7 you can pass an array of options to Auth::routes(). You can then disable the register routes with:

Auth::routes(['register' => false]);

You can see how this works from the source code: src/Illuminate/Routing/Router.php.

How to pass a variable from Activity to Fragment, and pass it back?

To pass info to a fragment , you setArguments when you create it, and you can retrieve this argument later on the method onCreate or onCreateView of your fragment.

On the newInstance function of your fragment you add the arguments you wanna send to it:

/**
 * Create a new instance of DetailsFragment, initialized to
 * show the text at 'index'.
 */
public static DetailsFragment newInstance(int index) {
    DetailsFragment f = new DetailsFragment();
    // Supply index input as an argument.
    Bundle args = new Bundle();
    args.putInt("index", index);
    f.setArguments(args);
    return f;
}

Then inside the fragment on the method onCreate or onCreateView you can retrieve the arguments like this:

Bundle args = getArguments();
int index = args.getInt("index", 0);

If you want now communicate from your fragment with your activity (sending or not data), you need to use interfaces. The way you can do this is explained really good in the documentation tutorial of communication between fragments. Because all fragments communicate between each other through the activity, in this tutorial you can see how you can send data from the actual fragment to his activity container to use this data on the activity or send it to another fragment that your activity contains.

Documentation tutorial:

http://developer.android.com/training/basics/fragments/communicating.html

git still shows files as modified after adding to .gitignore

Your .gitignore is working, but it still tracks the files because they were already in the index.

To stop this you have to do : git rm -r --cached .idea/

When you commit the .idea/ directory will be removed from your git repository and the following commits will ignore the .idea/ directory.

PS: You could use .idea/ instead of .idea/* to ignore a directory. You can find more info about the patterns on the .gitignore man page.


Helpful quote from the git-rm man page

--cached
    Use this option to unstage and remove paths only from the index. 
    Working tree files, whether modified or not, will be left alone.

Invalid character in identifier

You don't get a good error message in IDLE if you just Run the module. Try typing an import command from within IDLE shell, and you'll get a much more informative error message. I had the same error and that made all the difference.

(And yes, I'd copied the code from an ebook and it was full of invisible "wrong" characters.)

How can I check if the current date/time is past a set date/time?

date_default_timezone_set('Asia/Kolkata');

$curDateTime = date("Y-m-d H:i:s");
$myDate = date("Y-m-d H:i:s", strtotime("2018-06-26 16:15:33"));
if($myDate < $curDateTime){
    echo "active";exit;
}else{
    echo "inactive";exit;
}

How to convert a date string to different format

If you can live with 01 for January instead of 1, then try...

d = datetime.datetime.strptime("2013-1-25", '%Y-%m-%d')
print datetime.date.strftime(d, "%m/%d/%y")

You can check the docs for other formatting directives.

jQuery : select all element with custom attribute

As described by the link I've given in comment, this

$('p[MyTag]').each(function(index) {
  document.write(index + ': ' + $(this).text() + "<br>");});

works (playable example).

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

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

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

#!/bin/bash

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

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

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

BASE_URL="technetwork/java/javase/downloads"

# Put the whole page into a single string/line

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

# Define the environments to download 

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

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

echo
echo "JAVA_ENVIRONMENT="$JAVA_ENVIRONMENT
echo

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

echo "JAVA_BASE_VERSION="$JAVA_BASE_VERSION

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

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

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

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

# and echo out the link

echo "DOWNLOAD_LINK_OUTPUT="$DOWNLOAD_LINK_OUTPUT

done

done

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

Class name does not name a type in C++

The solution to my problem today was slightly different that the other answers here.

In my case, the problem was caused by a missing close bracket (}) at the end of one of the header files in the include chain.

Essentially, what was happening was that A was including B. Because B was missing a } somewhere in the file, the definitions in B were not correctly found in A.

At first I thought I have circular dependency and added the forward declaration B. But then it started complaining about the fact that something in B was an incomplete type. That's how I thought of double checking the files for syntax errors.

Resize iframe height according to content height in it

The trick is to acquire all the necessary iframe events from an external script. For instance, you have a script which creates the iFrame using document.createElement; in this same script you temporarily have access to the contents of the iFrame.

var dFrame = document.createElement("iframe");
dFrame.src = "http://www.example.com";
// Acquire onload and resize the iframe
dFrame.onload = function()
{
    // Setting the content window's resize function tells us when we've changed the height of the internal document
    // It also only needs to do what onload does, so just have it call onload
    dFrame.contentWindow.onresize = function() { dFrame.onload() };
    dFrame.style.height = dFrame.contentWindow.document.body.scrollHeight + "px";
}
window.onresize = function() {
    dFrame.onload();
}

This works because dFrame stays in scope in those functions, giving you access to the external iFrame element from within the scope of the frame, allowing you to see the actual document height and expand it as necessary. This example will work in firefox but nowhere else; I could give you the workarounds, but you can figure out the rest ;)

MySQL INNER JOIN select only one row from second table

SELECT u.*, p.*, max(p.date)
FROM payments p
JOIN users u ON u.id=p.user_id AND u.package = 1
GROUP BY u.id
ORDER BY p.date DESC

Check out this sqlfiddle

Could not find a declaration file for module 'module-name'. '/path/to/module-name.js' implicitly has an 'any' type

I was getting this too, had me baffled for a while, even with the module and types already installed and reloading my IDE several times.

What fixed it in my case was terminating terminal processes, removing node_modules, clearing the node package manager cache and doing a fresh install then re-loading the editor.

MySQL selecting yesterday's date

The simplest and best way to get yesterday's date is:

subdate(current_date, 1)

Your query would be:

SELECT 
    url as LINK,
    count(*) as timesExisted,
    sum(DateVisited between UNIX_TIMESTAMP(subdate(current_date, 1)) and
        UNIX_TIMESTAMP(current_date)) as timesVisitedYesterday
FROM mytable
GROUP BY 1

For the curious, the reason that sum(condition) gives you the count of rows that satisfy the condition, which would otherwise require a cumbersome and wordy case statement, is that in mysql boolean values are 1 for true and 0 for false, so summing a condition effectively counts how many times it's true. Using this pattern can neaten up your SQL code.

How to insert a SQLite record with a datetime set to 'now' in Android application?

Works for me perfect:

    values.put(DBHelper.COLUMN_RECEIVEDATE, geo.getReceiveDate().getTime());

Save your date as a long.

How to set HttpResponse timeout for Android in Java

If you are using the HttpURLConnection, call setConnectTimeout() as described here:

URL url = new URL(myurl);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(CONNECT_TIMEOUT);

How do I apply a perspective transform to a UIView?

As Ben said, you'll need to work with the UIView's layer, using a CATransform3D to perform the layer's rotation. The trick to get perspective working, as described here, is to directly access one of the matrix cells of the CATransform3D (m34). Matrix math has never been my thing, so I can't explain exactly why this works, but it does. You'll need to set this value to a negative fraction for your initial transform, then apply your layer rotation transforms to that. You should also be able to do the following:

Objective-C

UIView *myView = [[self subviews] objectAtIndex:0];
CALayer *layer = myView.layer;
CATransform3D rotationAndPerspectiveTransform = CATransform3DIdentity;
rotationAndPerspectiveTransform.m34 = 1.0 / -500;
rotationAndPerspectiveTransform = CATransform3DRotate(rotationAndPerspectiveTransform, 45.0f * M_PI / 180.0f, 0.0f, 1.0f, 0.0f);
layer.transform = rotationAndPerspectiveTransform;

Swift 5.0

if let myView = self.subviews.first {
    let layer = myView.layer
    var rotationAndPerspectiveTransform = CATransform3DIdentity
    rotationAndPerspectiveTransform.m34 = 1.0 / -500
    rotationAndPerspectiveTransform = CATransform3DRotate(rotationAndPerspectiveTransform, 45.0 * .pi / 180.0, 0.0, 1.0, 0.0)
    layer.transform = rotationAndPerspectiveTransform
}

which rebuilds the layer transform from scratch for each rotation.

A full example of this (with code) can be found here, where I've implemented touch-based rotation and scaling on a couple of CALayers, based on an example by Bill Dudney. The newest version of the program, at the very bottom of the page, implements this kind of perspective operation. The code should be reasonably simple to read.

The sublayerTransform you refer to in your response is a transform that is applied to the sublayers of your UIView's CALayer. If you don't have any sublayers, don't worry about it. I use the sublayerTransform in my example simply because there are two CALayers contained within the one layer that I'm rotating.

Postgresql Windows, is there a default password?

Try this:

Open PgAdmin -> Files -> Open pgpass.conf

You would get the path of pgpass.conf at the bottom of the window. Go to that location and open this file, you can find your password there.

Reference

If the above does not work, you may consider trying this:

 1. edit pg_hba.conf to allow trust authorization temporarily
 2. Reload the config file (pg_ctl reload)
 3. Connect and issue ALTER ROLE / PASSWORD to set the new password
 4. edit pg_hba.conf again and restore the previous settings
 5. Reload the config file again

Date constructor returns NaN in IE, but works in Firefox and Chrome

Try out using getDate feature of datepicker.

$.datepicker.formatDate('yy-mm-dd',new Date(pField.datepicker("getDate")));

Center a position:fixed element

Center fixed position element

It will not limit centered element's width less than viewport width, when using margins in flexbox inside centered element (a very good solution by far)

top: 0; left: 0;
transform: translate(calc(50vw - 50%));

Also for centering it vertically

top: 0; left: 0;
transform: translate(calc(50vw - 50%), calc(50vh - 50%));

Get yesterday's date in bash on Linux, DST-safe

As this question is tagged "DST safe"

And using fork to date command implie delay, there is a simple and more efficient way using pure bash built-in:

printf -v tznow '%(%z %s)T' -1
TZ=${tznow% *} printf -v yesterday '%(%Y-%m-%d)T' $(( ${tznow#* } - 86400 ))
echo $yesterday

This is a lot quicker on more system friendly than having to fork to date.

From V>=5.0, there is a new variable $EPOCHSECONDS

printf -v tz '%(%z)T' -1
TZ=$tz printf -v yesterday '%(%Y-%m-%d)T' $(( EPOCHSECONDS - 86400 ))
echo $yesterday

Using NotNull Annotation in method argument

I do this to create my own validation annotation and validator:

ValidCardType.java(annotation to put on methods/fields)

@Constraint(validatedBy = {CardTypeValidator.class})
@Documented
@Target( { ElementType.ANNOTATION_TYPE, ElementType.METHOD, ElementType.FIELD })
@Retention(RetentionPolicy.RUNTIME)
public @interface ValidCardType {
    String message() default "Incorrect card type, should be among: \"MasterCard\" | \"Visa\"";
    Class<?>[] groups() default {};
    Class<? extends Payload>[] payload() default {};
}

And, the validator to trigger the check: CardTypeValidator.java:

public class CardTypeValidator implements ConstraintValidator<ValidCardType, String> {
    private static final String[] ALL_CARD_TYPES = {"MasterCard", "Visa"};

    @Override
    public void initialize(ValidCardType status) {
    }
    public boolean isValid(String value, ConstraintValidatorContext context) {
        return (Arrays.asList(ALL_CARD_TYPES).contains(value));
    }
}

You can do something very similar to check @NotNull.

Random shuffling of an array

One of the solution is using the permutation to pre-compute all the permutations and stored in the ArrayList

Java 8 introduced a new method, ints(), in the java.util.Random class. The ints() method returns an unlimited stream of pseudorandom int values. You can limit the random numbers between a specified range by providing the minimum and the maximum values.

Random genRandom = new Random();
int num = genRandom.nextInt(arr.length);

With the help of generating the random number, You can iterate through the loop and swap with the current index with the random number.. That's how you can generate a random number with O(1) space complexity.

Check if a given time lies between two times regardless of date

There are lots of answers here but I want to provide a new one which is similar with Basil Bourque's answer but with a full code example. So please see the method below:

private static void checkTime(String startTime, String endTime, String checkTime) {
    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss", Locale.US);
    LocalTime startLocalTime = LocalTime.parse(startTime, formatter);
    LocalTime endLocalTime = LocalTime.parse(endTime, formatter);
    LocalTime checkLocalTime = LocalTime.parse(checkTime, formatter);

    boolean isInBetween = false;
    if (endLocalTime.isAfter(startLocalTime)) {
      if (startLocalTime.isBefore(checkLocalTime) && endLocalTime.isAfter(checkLocalTime)) {
          isInBetween = true;
      }
    } else if (checkLocalTime.isAfter(startLocalTime) || checkLocalTime.isBefore(endLocalTime)) {
        isInBetween = true;
    }

    if (isInBetween) {
        System.out.println("Is in between!");
    } else {
        System.out.println("Is not in between!");
    }
}

Either if you are calling this method using:

checkTime("20:11:13", "14:49:00", "01:00:00");

Or using:

checkTime("20:11:13", "14:49:00", "05:00:00");

The result will be:

Is in between!

How can I implement prepend and append with regular JavaScript?

If you want to insert a raw HTML string no matter how complex, you can use: insertAdjacentHTML, with appropriate first argument:

'beforebegin' Before the element itself. 'afterbegin' Just inside the element, before its first child. 'beforeend' Just inside the element, after its last child. 'afterend' After the element itself.

Hint: you can always call Element.outerHTML to get the HTML string representing the element to be inserted.

An example of usage:

document.getElementById("foo").insertAdjacentHTML("beforeBegin",
          "<div><h1>I</h1><h2>was</h2><h3>inserted</h3></div>");

DEMO

Caution: insertAdjacentHTML does not preserve listeners that where attached with .addEventLisntener.

How do I check two or more conditions in one <c:if>?

If you are using JSP 2.0 and above It will come with the EL support: so that you can write in plain english and use and with empty operators to write your test:

<c:if test="${(empty object_1.attribute_A) and (empty object_2.attribute_B)}">

Specifying trust store information in spring boot application.properties

I have the same problem, I'll try to explain it a bit more in detail.

I'm using spring-boot 1.2.2-RELEASE and tried it on both Tomcat and Undertow with the same result.

Defining the trust-store in application.yml like:

server:
  ssl:
    trust-store: path-to-truststore...
    trust-store-password: my-secret-password...

Doesn't work, while:

$ java -Djavax.net.debug=ssl -Djavax.net.ssl.trustStore=path-to-truststore... -Djavax.net.ssl.trustStorePassword=my-secret-password... -jar build/libs/*.jar  

works perfectly fine.

The easiest way to see the difference at rutime is to enable ssl-debug in the client. When working (i.e. using -D flags) something like the following is written to the console (during processing of the first request):

trustStore is: path-to-truststore...
trustStore type is : jks
trustStore provider is :
init truststore
adding as trusted cert:
  Subject: C=..., ST=..., O=..., OU=..., CN=...
  Issuer:  C=..., ST=..., O=..., OU=..., CN=...
  Algorithm: RSA; Serial number: 0x4d2
  Valid from Wed Oct 16 17:58:35 CEST 2013 until Tue Oct 11 17:58:35 CEST 2033

Without the -D flags I get:

trustStore is: /Library/Java/JavaVirtualMachines/jdk1.8.0_11.jdk/Contents/Home/jre/lib/security/cacerts
trustStore type is : jks
trustStore provider is :
init truststore
adding as trusted cert: ... (one for each CA-cert in the defult truststore)

...and when performing a request I get the exception:

sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

Hope it helps to understand the issue better!

How to reload the current route with the angular 2 router

Try this

window.open('dashboard', '_self');

its old method but works on all angular version, where it redirect on route and refresh the page.

Difference between signed / unsigned char

This because a char is stored at all effects as a 8-bit number. Speaking about a negative or positive char doesn't make sense if you consider it an ASCII code (which can be just signed*) but makes sense if you use that char to store a number, which could be in range 0-255 or in -128..127 according to the 2-complement representation.

*: it can be also unsigned, it actually depends on the implementation I think, in that case you will have access to extended ASCII charset provided by the encoding used

How to check if the request is an AJAX request with PHP

From PHP 7 with null coalescing operator it will be shorter:

$is_ajax = 'xmlhttprequest' == strtolower( $_SERVER['HTTP_X_REQUESTED_WITH'] ?? '' );

How do I prevent a parent's onclick event from firing when a child anchor is clicked?

Writing if anyone needs (worked for me):

event.stopImmediatePropagation()

From this solution.

Get Value of Radio button group

Your quotes only need to surround the value part of the attribute-equals selector, [attr='val'], like this:

$('a#check_var').click(function() {
  alert($("input:radio[name='r']:checked").val()+ ' '+
        $("input:radio[name='s']:checked").val());
});?

You can see the working version here.

Test if string begins with a string?

The best methods are already given but why not look at a couple of other methods for fun? Warning: these are more expensive methods but do serve in other circumstances.

The expensive regex method and the css attribute selector with starts with ^ operator

Option Explicit

Public Sub test()

    Debug.Print StartWithSubString("ab", "abc,d")

End Sub

Regex:

Public Function StartWithSubString(ByVal substring As String, ByVal testString As String) As Boolean
    'required reference Microsoft VBScript Regular Expressions
    Dim re As VBScript_RegExp_55.RegExp
    Set re = New VBScript_RegExp_55.RegExp

    re.Pattern = "^" & substring

    StartWithSubString = re.test(testString)

End Function

Css attribute selector with starts with operator

Public Function StartWithSubString(ByVal substring As String, ByVal testString As String) As Boolean
    'required reference Microsoft HTML Object Library
    Dim html As MSHTML.HTMLDocument
    Set html = New MSHTML.HTMLDocument

    html.body.innerHTML = "<div test=""" & testString & """></div>"

    StartWithSubString = html.querySelectorAll("[test^=" & substring & "]").Length > 0

End Function

How do I determine k when using k-means clustering?

Look at this paper, "Learning the k in k-means" by Greg Hamerly, Charles Elkan. It uses a Gaussian test to determine the right number of clusters. Also, the authors claim that this method is better than BIC which is mentioned in the accepted answer.

How to convert string to Date in Angular2 \ Typescript?

You can use date filter to convert in date and display in specific format.

In .ts file (typescript):

let dateString = '1968-11-16T00:00:00' 
let newDate = new Date(dateString);

In HTML:

{{dateString |  date:'MM/dd/yyyy'}}

Below are some formats which you can implement :

Backend:

public todayDate = new Date();

HTML :

<select>
<option value=""></option>
<option value="MM/dd/yyyy">[{{todayDate | date:'MM/dd/yyyy'}}]</option>
<option value="EEEE, MMMM d, yyyy">[{{todayDate | date:'EEEE, MMMM d, yyyy'}}]</option>
<option value="EEEE, MMMM d, yyyy h:mm a">[{{todayDate | date:'EEEE, MMMM d, yyyy h:mm a'}}]</option>
<option value="EEEE, MMMM d, yyyy h:mm:ss a">[{{todayDate | date:'EEEE, MMMM d, yyyy h:mm:ss a'}}]</option>
<option value="MM/dd/yyyy h:mm a">[{{todayDate | date:'MM/dd/yyyy h:mm a'}}]</option>
<option value="MM/dd/yyyy h:mm:ss a">[{{todayDate | date:'MM/dd/yyyy h:mm:ss a'}}]</option>
<option value="MMMM d">[{{todayDate | date:'MMMM d'}}]</option>   
<option value="yyyy-MM-ddTHH:mm:ss">[{{todayDate | date:'yyyy-MM-ddTHH:mm:ss'}}]</option>
<option value="h:mm a">[{{todayDate | date:'h:mm a'}}]</option>
<option value="h:mm:ss a">[{{todayDate | date:'h:mm:ss a'}}]</option>      
<option value="EEEE, MMMM d, yyyy hh:mm:ss a">[{{todayDate | date:'EEEE, MMMM d, yyyy hh:mm:ss a'}}]</option>
<option value="MMMM yyyy">[{{todayDate | date:'MMMM yyyy'}}]</option> 
</select>

How to append text to a text file in C++?

You could use an fstream and open it with the std::ios::app flag. Have a look at the code below and it should clear your head.

...
fstream f("filename.ext", f.out | f.app);
f << "any";
f << "text";
f << "written";
f << "wll";
f << "be append";
...

You can find more information about the open modes here and about fstreams here.

How do I add a .click() event to an image?

First of all, this line

<img src="http://soulsnatcher.bplaced.net/LDRYh.jpg" alt="unfinished bingo card" />.click()

You're mixing HTML and JavaScript. It doesn't work like that. Get rid of the .click() there.

If you read the JavaScript you've got there, document.getElementById('foo') it's looking for an HTML element with an ID of foo. You don't have one. Give your image that ID:

<img id="foo" src="http://soulsnatcher.bplaced.net/LDRYh.jpg" alt="unfinished bingo card" />

Alternatively, you could throw the JS in a function and put an onclick in your HTML:

<img src="http://soulsnatcher.bplaced.net/LDRYh.jpg" alt="unfinished bingo card" onclick="myfunction()" />

I suggest you do some reading up on JavaScript and HTML though.


The others are right about needing to move the <img> above the JS click binding too.

python: urllib2 how to send cookie with urlopen request

Use cookielib. The linked doc page provides examples at the end. You'll also find a tutorial here.

Disable double-tap "zoom" option in browser on touch devices

If you need a version that works without jQuery, I modified Wouter Konecny's answer (which was also created by modifying this gist by Johan Sundström) to use vanilla JavaScript.

function preventZoom(e) {
  var t2 = e.timeStamp;
  var t1 = e.currentTarget.dataset.lastTouch || t2;
  var dt = t2 - t1;
  var fingers = e.touches.length;
  e.currentTarget.dataset.lastTouch = t2;

  if (!dt || dt > 500 || fingers > 1) return; // not double-tap

  e.preventDefault();
  e.target.click();
}

Then add an event handler on touchstart that calls this function:

myButton.addEventListener('touchstart', preventZoom); 

Telnet is not recognized as internal or external command

  1. Open "Start" (Windows Button)
  2. Search for "Turn Windows features On or Off"
  3. Check "Telnet client" and check "Telnet server".

XAMPP Apache Webserver localhost not working on MAC OS

To be able to do this, you will have to stop apache from your terminal.

sudo apachectl stop

After you've done this, your apache server will be be up and running again!

Hope this helps

Missing maven .m2 folder

Is there some command to create this folder?

If smb face this issue again, you should know the most simple way to create .m2 folder.
If you unzipped maven and set up maven path variable - just try mvn clean command from anywhere you like!
Dont be afraid of error messages when running - it works and creates needed directory.

how to prevent css inherit

The short story is that it's not possible to do what you want here. There's no CSS rule which is to "ignore some other rule". The only way around it is to write a more-specific CSS rule for the inner elements which reverts it to how it was before, which is a pain in the butt.

Take the example below:

<div class="red"> <!-- ignore the semantics, it's an example, yo! -->
    <p class="blue">
        Blue text blue text!
        <span class="notBlue">this shouldn't be blue</span>
    </p>
</div>
<div class="green">
    <p class="blue">
        Blue text!
        <span class="notBlue">blah</span>
    </p>
</div>

There's no way to make the .notBlue class revert to the parent styling. The best you can do is this:

.red, .red .notBlue {
    color: red;
}
.green, .green .notBlue {
    color: green;
}

CSS show div background image on top of other contained elements

I would put an absolutely positioned, z-index: 100; span (or spans) with the background: url("myImageWithRoundedCorners.jpg"); set on it inside the #mainWrapperDivWithBGImage .

Upload files with HTTPWebrequest (multipart/form-data)

Took the above and modified it accept some header values, and multiple files

    NameValueCollection headers = new NameValueCollection();
        headers.Add("Cookie", "name=value;");
        headers.Add("Referer", "http://google.com");
    NameValueCollection nvc = new NameValueCollection();
        nvc.Add("name", "value");

    HttpUploadFile(url, new string[] { "c:\\file1.txt", "c:\\file2.jpg" }, new string[] { "file", "image" }, new string[] { "application/octet-stream", "image/jpeg" }, nvc, headers);

public static void HttpUploadFile(string url, string[] file, string[] paramName, string[] contentType, NameValueCollection nvc, NameValueCollection headerItems)
{
    //log.Debug(string.Format("Uploading {0} to {1}", file, url));
    string boundary = "---------------------------" + DateTime.Now.Ticks.ToString("x");
    byte[] boundarybytes = System.Text.Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");

    HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);

    foreach (string key in headerItems.Keys)
    {
        if (key == "Referer")
        {
            wr.Referer = headerItems[key];
        }
        else
        {
            wr.Headers.Add(key, headerItems[key]);
        }
    }

    wr.ContentType = "multipart/form-data; boundary=" + boundary;
    wr.Method = "POST";
    wr.KeepAlive = true;
    wr.Credentials = System.Net.CredentialCache.DefaultCredentials;

    Stream rs = wr.GetRequestStream();

    string formdataTemplate = "Content-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}";
    foreach (string key in nvc.Keys)
    {
        rs.Write(boundarybytes, 0, boundarybytes.Length);
        string formitem = string.Format(formdataTemplate, key, nvc[key]);
        byte[] formitembytes = System.Text.Encoding.UTF8.GetBytes(formitem);
        rs.Write(formitembytes, 0, formitembytes.Length);
    }
    rs.Write(boundarybytes, 0, boundarybytes.Length);

    string headerTemplate = "Content-Disposition: form-data; name=\"{0}\"; filename=\"{1}\"\r\nContent-Type: {2}\r\n\r\n";
    string header = "";

    for(int i =0; i<file.Count();i++)
    {
        header = string.Format(headerTemplate, paramName[i], System.IO.Path.GetFileName(file[i]), contentType[i]);
        byte[] headerbytes = System.Text.Encoding.UTF8.GetBytes(header);
        rs.Write(headerbytes, 0, headerbytes.Length);

        FileStream fileStream = new FileStream(file[i], FileMode.Open, FileAccess.Read);
        byte[] buffer = new byte[4096];
        int bytesRead = 0;
        while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
        {
            rs.Write(buffer, 0, bytesRead);
        }
        fileStream.Close();
        rs.Write(boundarybytes, 0, boundarybytes.Length);
    }
    rs.Close();

    WebResponse wresp = null;
    try
    {
        wresp = wr.GetResponse();
        Stream stream2 = wresp.GetResponseStream();
        StreamReader reader2 = new StreamReader(stream2);
        //log.Debug(string.Format("File uploaded, server response is: {0}", reader2.ReadToEnd()));
    }
    catch (Exception ex)
    {
        //log.Error("Error uploading file", ex);
            wresp.Close();
            wresp = null;
    }
    finally
    {
        wr = null;
    }
}

How to make a text box have rounded corners?

This can be done with CSS3:

<input type="text" />

input
{
  -moz-border-radius: 15px;
 border-radius: 15px;
    border:solid 1px black;
    padding:5px;
}

http://jsfiddle.net/UbSkn/1/


However, an alternative would be to put the input inside a div with a rounded background, and no border on the input

An error has occured. Please see log file - eclipse juno

In my case my JAVA_HOME was pointed to jdk9 after pointing JAVA_HOME to jdk8 resolved my issue. Hope it helps someone.

How to remove first 10 characters from a string?

You can use the method Substring method that takes a single parameter, which is the index to start from.

In my code below i deal with the case were the length is less than your desired start index and when the length is zero.

string s = "hello world!";
s = s.Substring(Math.Max(0, Math.Min(10, s.Length - 1)));

Converting VS2012 Solution to VS2010

I had a similar problem and none of the solutions above worked, so I went with an old standby that always works:

  1. Rename the folder containing the project
  2. Make a brand new project with the same name with 2010
  3. Diff the two folders and->
  4. Copy all source files directly
  5. Ignore bin/debug/release etc
  6. Diff the .csproj and copy over all lines that are relevant.
  7. If the .sln file only has one project, ignore it. If it's complex, then diff it as well.

That almost always works if you've spent 10 minutes at it and can't get it.

Note that for similar problems with older versions (2008, 2005) you can usually get away with just changing the version in the .csproj and either changing the version in the .sln or discarding it, but this doesn't seem to work for 2013.

How does one set up the Visual Studio Code compiler/debugger to GCC?

Caution

A friendly reminder: The following tutorial is for Linux user instead of Windows

Tutorial

If you want to debug your c++ code with GDB

You can read this ( Debugging your code ) article from Visual Studio Code official website.

Step 1: Compilation

You need to set up task.json for compilation of your cpp file

or simply type in the following command in the command window

g++ -g file.cpp -o file.exe

to generate a debuggable .exe file

Step 2: Set up the launch.json file

To enable debugging, you will need to generate a launch.json file

follow the launch.json example or google others

Step 3: Press (Ctrl+F5) to start compiling

this launch.json file will launch the configuration when you press the shortcut (Ctrl+F5)

Enjoy it!

ps. For those who want to set up tasks.json, you can read this from vscode official (-> TypeScript Hello World)

SQL Server remove milliseconds from datetime

Use CAST with following parameters:

Date

select Cast('2017-10-11 14:38:50.440' as date)

Output: 2017-10-11

Datetime

select Cast('2017-10-11 14:38:50.440' as datetime)

Output: 2017-10-11 14:38:50.440

SmallDatetime

select Cast('2017-10-11 14:38:50.440' as smalldatetime)

Output: 2017-10-11 14:39:00

DatetimeOffset

select Cast('2017-10-11 14:38:50.440' as datetimeoffset)

Output: 2017-10-11 14:38:50.4400000 +00:00

Datetime2

select Cast('2017-10-11 14:38:50.440' as datetime2)

Output: 2017-10-11 14:38:50.4400000

Python Finding Prime Factors

def prime(n):
    for i in range(2,n):
        if n%i==0:
            return False
    return True

def primefactors():
    m=int(input('enter the number:'))
    for i in range(2,m):
        if (prime(i)):
            if m%i==0:
                print(i)
    return print('end of it')

primefactors()

Java Date vs Calendar

Date is a simpler class and is mainly there for backward compatibility reasons. If you need to set particular dates or do date arithmetic, use a Calendar. Calendars also handle localization. The previous date manipulation functions of Date have since been deprecated.

Personally I tend to use either time in milliseconds as a long (or Long, as appropriate) or Calendar when there is a choice.

Both Date and Calendar are mutable, which tends to present issues when using either in an API.

Empty an array in Java / processing

If Array xco is not final then a simple reassignment would work:

i.e.

xco = new Float[xco .length];

This assumes you need the Array xco to remain the same size. If that's not necessary then create an empty array:

xco= new Float[0];

Java: method to get position of a match in a String?

I have some big code but working nicely....

   class strDemo
   { 
       public static void main(String args[])
       {
       String s1=new String("The Ghost of The Arabean Sea");
           String s2=new String ("The");
           String s6=new String ("ehT");
           StringBuffer s3;
           StringBuffer s4=new StringBuffer(s1);
           StringBuffer s5=new StringBuffer(s2);
           char c1[]=new char[30];
           char c2[]=new char[5];
           char c3[]=new char[5];
           s1.getChars(0,28,c1,0);
           s2.getChars(0,3,c2,0);
           s6.getChars(0,3,c3,0); s3=s4.reverse();      
           int pf=0,pl=0;
           char c5[]=new char[30];
           s3.getChars(0,28,c5,0);
           for(int i=0;i<(s1.length()-s2.length());i++)
           {
               int j=0;
               if(pf<=1)
               {
                  while (c1[i+j]==c2[j] && j<=s2.length())
                  {           
                    j++;
                    System.out.println(s2.length()+" "+j);
                    if(j>=s2.length())
                    {
                       System.out.println("first match of(The) :->"+i);

                     }
                     pf=pf+1;         
                  }   
             }                
       }       
         for(int i=0;i<(s3.length()-s6.length()+1);i++)
        {
            int j=0;
            if(pl<=1)
            {
             while (c5[i+j]==c3[j] && j<=s6.length())
             {
                 j++;
                 System.out.println(s6.length()+" "+j);
                 if(j>=s6.length())
                 {
                         System.out.println((s3.length()-i-3));
                         pl=pl+1;

                 }   
                }                 
              }  
           }  
         }
       }

What's wrong with foreign keys?

"They can make deleting records more cumbersome - you can't delete the "master" record where there are records in other tables where foreign keys would violate that constraint."

It's important to remember that the SQL standard defines actions that are taken when a foreign key is deleted or updated. The ones I know of are:

  • ON DELETE RESTRICT - Prevents any rows in the other table that have keys in this column from being deleted. This is what Ken Ray described above.
  • ON DELETE CASCADE - If a row in the other table is deleted, delete any rows in this table that reference it.
  • ON DELETE SET DEFAULT - If a row in the other table is deleted, set any foreign keys referencing it to the column's default.
  • ON DELETE SET NULL - If a row in the other table is deleted, set any foreign keys referencing it in this table to null.
  • ON DELETE NO ACTION - This foreign key only marks that it is a foreign key; namely for use in OR mappers.

These same actions also apply to ON UPDATE.

The default seems to depend on which server you're using.

byte[] to hex string

I'm not sure if you need perfomance for doing this, but here is the fastest method to convert byte[] to hex string that I can think of :

static readonly char[] hexchar = new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
public static string HexStr(byte[] data, int offset, int len, bool space = false)
{
    int i = 0, k = 2;
    if (space) k++;
    var c = new char[len * k];
    while (i < len)
    {
        byte d = data[offset + i];
        c[i * k] = hexchar[d / 0x10];
        c[i * k + 1] = hexchar[d % 0x10];
        if (space && i < len - 1) c[i * k + 2] = ' ';
        i++;
    }
    return new string(c, 0, c.Length);
}

Vertical dividers on horizontal UL menu

Quite and simple without any "having to specify the first element". CSS is more powerful than most think (e.g. the first-child:before is great!). But this is by far the cleanest and most proper way to do this, at least in my opinion it is.

#navigation ul
{
    margin: 0;
    padding: 0;
}

#navigation ul li
{
    list-style-type: none;
    display: inline;
}

#navigation li:not(:first-child):before {
    content: " | ";
}

Now just use a simple unordered list in HTML and it'll populate it for you. HTML should look like this:

<div id="navigation">
    <ul>
        <li><a href="#">Home</a></li>
        <li><a href="#">About Us</a></li>
        <li><a href="#">Support</a></li>
    </ul>
</div><!-- navigation -->

The result will be just like this:

HOME | ABOUT US | SUPPORT

Now you can indefinitely expand and never have to worry about order, changing links, or your first entry. It's all automated and works great!

100% width Twitter Bootstrap 3 template

For Bootstrap 3, you would need to use a custom wrapper and set its width to 100%.

.container-full {
  margin: 0 auto;
  width: 100%;
}

Here is a working example on Bootply

If you prefer not to add a custom class, you can acheive a very wide layout (not 100%) by wrapping everything inside a col-lg-12 (wide layout demo)

Update for Bootstrap 3.1

The container-fluid class has returned in Bootstrap 3.1, so this can be used to create a full width layout (no additional CSS required)..

Bootstrap 3.1 demo

jquery how to catch enter key and change event to tab

Here's a jQuery plugin I wrote that handles enter key as a callback or as a tab key (with an optional callback):

_x000D_
_x000D_
$(document).ready(function() {_x000D_
  $('#one').onEnter('tab');_x000D_
  $('#two').onEnter('tab');_x000D_
  $('#three').onEnter('tab');_x000D_
  $('#four').onEnter('tab');_x000D_
  $('#five').onEnter('tab');_x000D_
});_x000D_
_x000D_
/**_x000D_
 * jQuery.onEnter.js_x000D_
 * Written by: Jay Simons_x000D_
 * Cloudulus.Media (https://code.cloudulus.media)_x000D_
 */_x000D_
_x000D_
if (window.jQuery) {_x000D_
    (function ($) {_x000D_
        $.fn.onEnter = function (opt1, opt2, opt3) {_x000D_
            return this.on('keyup', function (e) {_x000D_
                var me = $(this);_x000D_
                var code = e.keyCode ? e.keyCode : e.which;_x000D_
                if (code == 13) {_x000D_
                    if (typeof opt1 == 'function')_x000D_
                    {_x000D_
                        opt1(me, opt2);_x000D_
                        return true;_x000D_
                    }else if (opt1 == 'tab')_x000D_
                    {_x000D_
                        var eles = $(document).find('input,select,textarea,button').filter(':visible:not(:disabled):not([readonly])');_x000D_
                        var foundMe = false;_x000D_
                        var next = null;_x000D_
                        eles.each(function(){_x000D_
                            if (!next){_x000D_
                                if (foundMe) next = $(this);_x000D_
                                if (JSON.stringify($(this)) == JSON.stringify(me)) foundMe = true;_x000D_
                            }_x000D_
                        });_x000D_
                        next.focus();_x000D_
                        if (typeof opt2 === 'function')_x000D_
                        {_x000D_
                            opt2(me, opt3);_x000D_
                        }_x000D_
                        return true;_x000D_
                    }_x000D_
                }_x000D_
            }).on('keydown', function(e){_x000D_
                var code = e.keyCode ? e.keyCode : e.which;_x000D_
                if (code == 13)_x000D_
                {_x000D_
                    e.preventDefault();_x000D_
                    e.stopPropagation();_x000D_
                    return false;_x000D_
                }_x000D_
            });_x000D_
        }_x000D_
    })(jQuery);_x000D_
} else {_x000D_
    console.log("onEnter.js: This class requies jQuery > v3!");_x000D_
}
_x000D_
input,_x000D_
select,_x000D_
textarea,_x000D_
button {_x000D_
  display: block;_x000D_
  margin-bottom: 1em;_x000D_
}
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<form>_x000D_
  <input id="one" type="text" placeholder="Input 1" />_x000D_
  <input id="two" type="text" placeholder="Input 2" />_x000D_
_x000D_
  <select id="four">_x000D_
    <option selected>A Select Box</option>_x000D_
    <option>Opt 1</option>_x000D_
    <option>Opt 2</option>_x000D_
  </select>_x000D_
  <textarea id="five" placeholder="A textarea"></textarea>_x000D_
  <input id="three" type="text" placeholder="Input 3" />_x000D_
  <button>A Button</button>_x000D_
</form>
_x000D_
_x000D_
_x000D_

How to query a CLOB column in Oracle

I did run into another condition with HugeClob in my Oracle database. The dbms_lob.substr only allowed a value of 4000 in the function, ex:

dbms_lob.substr(column,4000,1)

so for my HughClob which was larger, I had to use two calls in select:

select dbms_lob.substr(column,4000,1) part1, 
       dbms_lob.substr(column,4000,4001) part2 from .....

I was calling from a Java app so I simply concatenated part1 and part2 and sent as a email.

Improve INSERT-per-second performance of SQLite

After reading this tutorial, I tried to implement it to my program.

I have 4-5 files that contain addresses. Each file has approx 30 million records. I am using the same configuration that you are suggesting but my number of INSERTs per second is way low (~10.000 records per sec).

Here is where your suggestion fails. You use a single transaction for all the records and a single insert with no errors/fails. Let's say that you are splitting each record into multiple inserts on different tables. What happens if the record is broken?

The ON CONFLICT command does not apply, cause if you have 10 elements in a record and you need each element inserted to a different table, if element 5 gets a CONSTRAINT error, then all previous 4 inserts need to go too.

So here is where the rollback comes. The only issue with the rollback is that you lose all your inserts and start from the top. How can you solve this?

My solution was to use multiple transactions. I begin and end a transaction every 10.000 records (Don't ask why that number, it was the fastest one I tested). I created an array sized 10.000 and insert the successful records there. When the error occurs, I do a rollback, begin a transaction, insert the records from my array, commit and then begin a new transaction after the broken record.

This solution helped me bypass the issues I have when dealing with files containing bad/duplicate records (I had almost 4% bad records).

The algorithm I created helped me reduce my process by 2 hours. Final loading process of file 1hr 30m which is still slow but not compared to the 4hrs that it initially took. I managed to speed the inserts from 10.000/s to ~14.000/s

If anyone has any other ideas on how to speed it up, I am open to suggestions.

UPDATE:

In Addition to my answer above, you should keep in mind that inserts per second depending on the hard drive you are using too. I tested it on 3 different PCs with different hard drives and got massive differences in times. PC1 (1hr 30m), PC2 (6hrs) PC3 (14hrs), so I started wondering why would that be.

After two weeks of research and checking multiple resources: Hard Drive, Ram, Cache, I found out that some settings on your hard drive can affect the I/O rate. By clicking properties on your desired output drive you can see two options in the general tab. Opt1: Compress this drive, Opt2: Allow files of this drive to have contents indexed.

By disabling these two options all 3 PCs now take approximately the same time to finish (1hr and 20 to 40min). If you encounter slow inserts check whether your hard drive is configured with these options. It will save you lots of time and headaches trying to find the solution

NodeJS w/Express Error: Cannot GET /

I found myself on this page as I was also receiving the Cannot GET/ message. My circumstances differed as I was using express.static() to target a folder, as has been offered in previous answers, and not a file as the OP was.

What I discovered after some digging through Express' docs is that express.static() defines its index file as index.html, whereas my file was named index.htm.

To tie this to the OP's question, there are two options:

1: Use the code suggested in other answers

app.use(express.static(__dirname));

and then rename default.htm file to index.html

or

2: Add the index property when calling express.static() to direct it to the desired index file:

app.use(express.static(__dirname, { index: 'default.htm' }));

How to disable a input in angular2

Demo

make is_edit of type boolean.

<input [disabled]=is_edit id="name" type="text">

export class App {
  name:string;
  is_edit: boolean; 
  constructor() {
    this.name = 'Angular2'
    this.is_edit = true;
  }
}

Convert string to number and add one

Simple and best solution is like this. take a string in one variable and then convert it using parseInt() method like below.

var stringValue = '921795';
var numValue = parseInt(stringValue);

parseInt() method will return the number like this 921795. after this, you can add any number to your value.

http://www.phpcodify.com/convert-string-to-integer-using-jquery-parseint/

Column standard deviation R

The package fBasics has a function colStdevs

 require('fBasics')
 set.seed(123)
 colStdevs(matrix(rnorm(1000, mean=10, sd=1), ncol=5))
[1] 0.9431599 0.9959210 0.9648052 1.0246366 1.0351268

Match linebreaks - \n or \r\n?

Gonna answer in opposite direction.

2) For a full explanation about \r and \n I have to refer to this question, which is far more complete than I will post here: Difference between \n and \r?

Long story short, Linux uses \n for a new-line, Windows \r\n and old Macs \r. So there are multiple ways to write a newline. Your second tool (RegExr) does for example match on the single \r.

1) [\r\n]+ as Ilya suggested will work, but will also match multiple consecutive new-lines. (\r\n|\r|\n) is more correct.

Getting the minimum of two values in SQL

Here is a trick if you want to calculate maximum(field, 0):

SELECT (ABS(field) + field)/2 FROM Table

returns 0 if field is negative, else, return field.

How to kill a child process by the parent process?

Try something like this:

#include <signal.h>

pid_t child_pid = -1 ; //Global

void kill_child(int sig)
{
    kill(child_pid,SIGKILL);
}

int main(int argc, char *argv[])
{
    signal(SIGALRM,(void (*)(int))kill_child);
    child_pid = fork();
    if (child_pid > 0) {
     /*PARENT*/
        alarm(30);
        /*
         * Do parent's tasks here.
         */
        wait(NULL);
    }
    else if (child_pid == 0){
     /*CHILD*/
        /*
         * Do child's tasks here.
         */
    }
}

How to find time complexity of an algorithm

When you're analyzing code, you have to analyse it line by line, counting every operation/recognizing time complexity, in the end, you have to sum it to get whole picture.

For example, you can have one simple loop with linear complexity, but later in that same program you can have a triple loop that has cubic complexity, so your program will have cubic complexity. Function order of growth comes into play right here.

Let's look at what are possibilities for time complexity of an algorithm, you can see order of growth I mentioned above:

  • Constant time has an order of growth 1, for example: a = b + c.

  • Logarithmic time has an order of growth LogN, it usually occurs when you're dividing something in half (binary search, trees, even loops), or multiplying something in same way.

  • Linear, order of growth is N, for example

    int p = 0;
    for (int i = 1; i < N; i++)
      p = p + 2;
    
  • Linearithmic, order of growth is n*logN, usually occurs in divide and conquer algorithms.

  • Cubic, order of growth N^3, classic example is a triple loop where you check all triplets:

    int x = 0;
    for (int i = 0; i < N; i++)
       for (int j = 0; j < N; j++)
          for (int k = 0; k < N; k++)
              x = x + 2
    
  • Exponential, order of growth 2^N, usually occurs when you do exhaustive search, for example check subsets of some set.

Format number as percent in MS SQL Server

Using FORMAT function in new versions of SQL Server is much simpler and allows much more control:

FORMAT(yournumber, '#,##0.0%')

Benefit of this is you can control additional things like thousand separators and you don't get that space between the number and '%'.

ImageView in android XML layout with layout_height="wrap_content" has padding top & bottom

I had a simular issue and resolved it using android:adjustViewBounds="true" on the ImageView.

<ImageView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:adjustViewBounds="true"
    android:contentDescription="@string/banner_alt"
    android:src="@drawable/banner_portrait" />

How to remove listview all items

I just clean the arraylist , try values.clear();

values = new ArrayList<String>();
values.clear();

ArrayAdapter <String> adapter;
adapter = new ArrayAdapter<String>(this, R.layout.list,android.R.id.text1, values); 
lista.setAdapter(adapter);

Jquery Smooth Scroll To DIV - Using ID value from Link

Ids are meant to be unique, and never use an id that starts with a number, use data-attributes instead to set the target like so :

<div id="searchbycharacter">
    <a class="searchbychar" href="#" data-target="numeric">0-9 |</a> 
    <a class="searchbychar" href="#" data-target="A"> A |</a> 
    <a class="searchbychar" href="#" data-target="B"> B |</a> 
    <a class="searchbychar" href="#" data-target="C"> C |</a> 
    ... Untill Z
</div>

As for the jquery :

$(document).on('click','.searchbychar', function(event) {
    event.preventDefault();
    var target = "#" + this.getAttribute('data-target');
    $('html, body').animate({
        scrollTop: $(target).offset().top
    }, 2000);
});

C# - Substring: index and length must refer to a location within the string

Try This:

 int positionOfJPG=url.IndexOf(".jpg");
 string newString = url.Substring(18, url.Length - positionOfJPG);

Padding is invalid and cannot be removed?

My issue was that the encrypt's passPhrase didn't match the decrypt's passPhrase... so it threw this error .. a little misleading.

Load HTML page dynamically into div with jQuery

I think this would do it:

<html>
<head>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
<script type="text/javascript">
    $(document).ready(function(){

         $(".divlink").click(function(){
         $("#content").attr("src" , $(this).attr("ref"));

});

});
</script>
</head>
<body>
<iframe id="content"></iframe>

<a href="#" ref="page1.html" class="divlink" >Page 1</a><br />
<a href="#" ref="page2.html" class="divlink" >Page 2</a><br />
<a href="#" ref="page3.html" class="divlink" >Page 3</a><br />
<a href="#" ref="page4.html" class="divlink" >Page 4</a><br />
<a href="#" ref="page5.html" class="divlink" >Page 5</a><br />
<a href="#" ref="page6.html" class="divlink" >Page 6</a><br />
</body>
</html>

By the way if you can avoid Jquery, you can just use the target attribute of <a> element:

<html>
<body>
<iframe id="content" name="content"></iframe>

<a href="page1.html" target="content" >Page 1</a><br />
<a href="page2.html" target="content" >Page 2</a><br />
<a href="page3.html" target="content" >Page 3</a><br />
<a href="page4.html" target="content" >Page 4</a><br />
<a href="page5.html" target="content" >Page 5</a><br />
<a href="page6.html" target="content" >Page 6</a><br />
</body>
</html> 

How to inject JPA EntityManager using spring

The latest Spring + JPA versions solve this problem fundamentally. You can learn more how to use Spring and JPA togather in a separate thread

Check if a div does NOT exist with javascript

That works with :

 var element = document.getElementById('myElem');
 if (typeof (element) != undefined && typeof (element) != null && typeof (element) != 'undefined') {
     console.log('element exists');
 }
 else{
     console.log('element NOT exists');
 }

jQuery - trapping tab select event

The correct method for capturing tab selection event is to set a function as the value for the select option when initializing the tabs (you can also set them dynamically afterwards), like so:

$('#tabs, #fragment-1').tabs({
  select: function(event, ui){
    // Do stuff here
  }
});

You can see the actual code in action here: http://jsfiddle.net/mZLDk/


Edit: With the link you gave me, I've created a test environment for jQuery 1.2.3 with jQuery UI 1.5 (I think?). Some things obviously changed from then. There wasn't a separate ui object which was separated from the original event object. The code looks something like this:

// Tab initialization
$('#container ul').tabs({
    select: function(event) {
        // You need Firebug or the developer tools on your browser open to see these
        console.log(event);
        // This will get you the index of the tab you selected
        console.log(event.options.selected);
        // And this will get you it's name
        console.log(event.tab.text);
    }
});

Phew. If there's anything to learn here, it's that supporting legacy code is hard. See the jsfiddle for more: http://jsfiddle.net/qCfnL/1/


Edit: For those who is using newer version of jQuery, try the following:

$("#tabs").tabs({
    activate: function (event, ui) {
        console.log(event);
    }
});

Inserting the same value multiple times when formatting a string

You can use advanced string formatting, available in Python 2.6 and Python 3.x:

incoming = 'arbit'
result = '{0} hello world {0} hello world {0}'.format(incoming)

How can I reset or revert a file to a specific revision?

This is a very simple step. Checkout file to the commit id we want, here one commit id before, and then just git commit amend and we are done.

# git checkout <previous commit_id> <file_name>
# git commit --amend

This is very handy. If we want to bring any file to any prior commit id at the top of commit, we can easily do.

"Fatal error: Unable to find local grunt." when running "grunt" command

You have to install grunt in your project folder

  1. create your package.json

    $ npm init
    
  2. install grunt for this project, this will be installed under node_modules/. --save-dev will add this module to devDependency in your package.json

    $ npm install grunt --save-dev
    
  3. then create gruntfile.js and run

    $ grunt 
    

Check that an email address is valid on iOS

Good cocoa function:

-(BOOL) NSStringIsValidEmail:(NSString *)checkString
{
   BOOL stricterFilter = NO; // Discussion http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/
   NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
   NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
   NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
   NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
   return [emailTest evaluateWithObject:checkString];
}

Discussion on Lax vs. Strict - http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/

And because categories are just better, you could also add an interface:

@interface NSString (emailValidation) 
  - (BOOL)isValidEmail;
@end

Implement

@implementation NSString (emailValidation)
-(BOOL)isValidEmail
{
  BOOL stricterFilter = NO; // Discussion http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/
  NSString *stricterFilterString = @"^[A-Z0-9a-z\\._%+-]+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2,4}$";
  NSString *laxString = @"^.+@([A-Za-z0-9-]+\\.)+[A-Za-z]{2}[A-Za-z]*$";
  NSString *emailRegex = stricterFilter ? stricterFilterString : laxString;
  NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];
  return [emailTest evaluateWithObject:self];
}
@end

And then utilize:

if([@"[email protected]" isValidEmail]) { /* True */ }
if([@"InvalidEmail@notreallyemailbecausenosuffix" isValidEmail]) { /* False */ }

PHP import Excel into database (xls & xlsx)

This is best plugin with proper documentation and examples

https://github.com/PHPOffice/PHPExcel

Plus point: you can ask for help in its discussion forum and you will get response within a day from the author itself, really impressive.

How do I generate a random int number?

Random rand = new Random();
int name = rand.Next()

Put whatever values you want in the second parentheses make sure you have set a name by writing prop and double tab to generate the code

linux shell script: split string, put them in an array then loop through them

sentence="one;two;three"
a="${sentence};"
while [ -n "${a}" ]
do
    echo ${a%%;*}
    a=${a#*;}
done

How to copy and paste code without rich text formatting?

I have Far.exe as the first item in the start menu.

Richtext in the clipboard ->

ctrl-escape,arrdown,enter,shift-f4,$,enter
shift-insert,ctrl-insert,alt-backspace,
f10,enter

-> plaintext in the clipboard

Pros: no mouse, just blind typing, ends exactly where i was before

Cons: ANSI encoding - international symbols are lost

Luckily, I do not have to do that too often :)

REST / SOAP endpoints for a WCF service

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

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

An example of endpoint configuration in your scenario is

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

so, the service will be available at

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

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

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

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

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

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

POX behavior for REST Plain Old XML

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

Endpoints

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

Service will be available at

REST request try it in browser,

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

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

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

in C#

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

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

How to filter a RecyclerView with a SearchView

Introduction

Since it is not really clear from your question what exactly you are having trouble with, I wrote up this quick walkthrough about how to implement this feature; if you still have questions feel free to ask.

I have a working example of everything I am talking about here in this GitHub Repository.
If you want to know more about the example project visit the project homepage.

In any case the result should looks something like this:

demo image

If you first want to play around with the demo app you can install it from the Play Store:

Get it on Google Play

Anyway lets get started.


Setting up the SearchView

In the folder res/menu create a new file called main_menu.xml. In it add an item and set the actionViewClass to android.support.v7.widget.SearchView. Since you are using the support library you have to use the namespace of the support library to set the actionViewClass attribute. Your xml file should look something like this:

<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto">

    <item android:id="@+id/action_search"
          android:title="@string/action_search"
          app:actionViewClass="android.support.v7.widget.SearchView"
          app:showAsAction="always"/>

</menu>

In your Fragment or Activity you have to inflate this menu xml like usual, then you can look for the MenuItem which contains the SearchView and implement the OnQueryTextListener which we are going to use to listen for changes to the text entered into the SearchView:

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);

    final MenuItem searchItem = menu.findItem(R.id.action_search);
    final SearchView searchView = (SearchView) searchItem.getActionView();
    searchView.setOnQueryTextListener(this);

    return true;
}

@Override
public boolean onQueryTextChange(String query) {
    // Here is where we are going to implement the filter logic
    return false;
}

@Override
public boolean onQueryTextSubmit(String query) {
    return false;
}

And now the SearchView is ready to be used. We will implement the filter logic later on in onQueryTextChange() once we are finished implementing the Adapter.


Setting up the Adapter

First and foremost this is the model class I am going to use for this example:

public class ExampleModel {

    private final long mId;
    private final String mText;

    public ExampleModel(long id, String text) {
        mId = id;
        mText = text;
    }

    public long getId() {
        return mId;
    }

    public String getText() {
        return mText;
    }
}

It's just your basic model which will display a text in the RecyclerView. This is the layout I am going to use to display the text:

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">

    <data>

        <variable
            name="model"
            type="com.github.wrdlbrnft.searchablerecyclerviewdemo.ui.models.ExampleModel"/>

    </data>

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="?attr/selectableItemBackground"
        android:clickable="true">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:padding="8dp"
            android:text="@{model.text}"/>

    </FrameLayout>

</layout>

As you can see I use Data Binding. If you have never worked with data binding before don't be discouraged! It's very simple and powerful, however I can't explain how it works in the scope of this answer.

This is the ViewHolder for the ExampleModel class:

public class ExampleViewHolder extends RecyclerView.ViewHolder {

    private final ItemExampleBinding mBinding;

    public ExampleViewHolder(ItemExampleBinding binding) {
        super(binding.getRoot());
        mBinding = binding;
    }

    public void bind(ExampleModel item) {
        mBinding.setModel(item);
    }
}

Again nothing special. It just uses data binding to bind the model class to this layout as we have defined in the layout xml above.

Now we can finally come to the really interesting part: Writing the Adapter. I am going to skip over the basic implementation of the Adapter and am instead going to concentrate on the parts which are relevant for this answer.

But first there is one thing we have to talk about: The SortedList class.


SortedList

The SortedList is a completely amazing tool which is part of the RecyclerView library. It takes care of notifying the Adapter about changes to the data set and does so it a very efficient way. The only thing it requires you to do is specify an order of the elements. You need to do that by implementing a compare() method which compares two elements in the SortedList just like a Comparator. But instead of sorting a List it is used to sort the items in the RecyclerView!

The SortedList interacts with the Adapter through a Callback class which you have to implement:

private final SortedList.Callback<ExampleModel> mCallback = new SortedList.Callback<ExampleModel>() {

    @Override
    public void onInserted(int position, int count) {
         mAdapter.notifyItemRangeInserted(position, count);
    }

    @Override
    public void onRemoved(int position, int count) {
        mAdapter.notifyItemRangeRemoved(position, count);
    }

    @Override
    public void onMoved(int fromPosition, int toPosition) {
        mAdapter.notifyItemMoved(fromPosition, toPosition);
    }

    @Override
    public void onChanged(int position, int count) {
        mAdapter.notifyItemRangeChanged(position, count);
    }

    @Override
    public int compare(ExampleModel a, ExampleModel b) {
        return mComparator.compare(a, b);
    }

    @Override
    public boolean areContentsTheSame(ExampleModel oldItem, ExampleModel newItem) {
        return oldItem.equals(newItem);
    }

    @Override
    public boolean areItemsTheSame(ExampleModel item1, ExampleModel item2) {
        return item1.getId() == item2.getId();
    }
}

In the methods at the top of the callback like onMoved, onInserted, etc. you have to call the equivalent notify method of your Adapter. The three methods at the bottom compare, areContentsTheSame and areItemsTheSame you have to implement according to what kind of objects you want to display and in what order these objects should appear on the screen.

Let's go through these methods one by one:

@Override
public int compare(ExampleModel a, ExampleModel b) {
    return mComparator.compare(a, b);
}

This is the compare() method I talked about earlier. In this example I am just passing the call to a Comparator which compares the two models. If you want the items to appear in alphabetical order on the screen. This comparator might look like this:

private static final Comparator<ExampleModel> ALPHABETICAL_COMPARATOR = new Comparator<ExampleModel>() {
    @Override
    public int compare(ExampleModel a, ExampleModel b) {
        return a.getText().compareTo(b.getText());
    }
};

Now let's take a look at the next method:

@Override
public boolean areContentsTheSame(ExampleModel oldItem, ExampleModel newItem) {
    return oldItem.equals(newItem);
}

The purpose of this method is to determine if the content of a model has changed. The SortedList uses this to determine if a change event needs to be invoked - in other words if the RecyclerView should crossfade the old and new version. If you model classes have a correct equals() and hashCode() implementation you can usually just implement it like above. If we add an equals() and hashCode() implementation to the ExampleModel class it should look something like this:

public class ExampleModel implements SortedListAdapter.ViewModel {

    private final long mId;
    private final String mText;

    public ExampleModel(long id, String text) {
        mId = id;
        mText = text;
    }

    public long getId() {
        return mId;
    }

    public String getText() {
        return mText;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        ExampleModel model = (ExampleModel) o;

        if (mId != model.mId) return false;
        return mText != null ? mText.equals(model.mText) : model.mText == null;

    }

    @Override
    public int hashCode() {
        int result = (int) (mId ^ (mId >>> 32));
        result = 31 * result + (mText != null ? mText.hashCode() : 0);
        return result;
    }
}

Quick side note: Most IDE's like Android Studio, IntelliJ and Eclipse have functionality to generate equals() and hashCode() implementations for you at the press of a button! So you don't have to implement them yourself. Look up on the internet how it works in your IDE!

Now let's take a look at the last method:

@Override
public boolean areItemsTheSame(ExampleModel item1, ExampleModel item2) {
    return item1.getId() == item2.getId();
}

The SortedList uses this method to check if two items refer to the same thing. In simplest terms (without explaining how the SortedList works) this is used to determine if an object is already contained in the List and if either an add, move or change animation needs to be played. If your models have an id you would usually compare just the id in this method. If they don't you need to figure out some other way to check this, but however you end up implementing this depends on your specific app. Usually it is the simplest option to give all models an id - that could for example be the primary key field if you are querying the data from a database.

With the SortedList.Callback correctly implemented we can create an instance of the SortedList:

final SortedList<ExampleModel> list = new SortedList<>(ExampleModel.class, mCallback);

As the first parameter in the constructor of the SortedList you need to pass the class of your models. The other parameter is just the SortedList.Callback we defined above.

Now let's get down to business: If we implement the Adapter with a SortedList it should look something like this:

public class ExampleAdapter extends RecyclerView.Adapter<ExampleViewHolder> {

    private final SortedList<ExampleModel> mSortedList = new SortedList<>(ExampleModel.class, new SortedList.Callback<ExampleModel>() {
        @Override
        public int compare(ExampleModel a, ExampleModel b) {
            return mComparator.compare(a, b);
        }

        @Override
        public void onInserted(int position, int count) {
            notifyItemRangeInserted(position, count);
        }

        @Override
        public void onRemoved(int position, int count) {
            notifyItemRangeRemoved(position, count);
        }

        @Override
        public void onMoved(int fromPosition, int toPosition) {
            notifyItemMoved(fromPosition, toPosition);
        }

        @Override
        public void onChanged(int position, int count) {
            notifyItemRangeChanged(position, count);
        }

        @Override
        public boolean areContentsTheSame(ExampleModel oldItem, ExampleModel newItem) {
            return oldItem.equals(newItem);
        }

        @Override
        public boolean areItemsTheSame(ExampleModel item1, ExampleModel item2) {
            return item1.getId() == item2.getId();
        }
    });

    private final LayoutInflater mInflater;
    private final Comparator<ExampleModel> mComparator;

    public ExampleAdapter(Context context, Comparator<ExampleModel> comparator) {
        mInflater = LayoutInflater.from(context);
        mComparator = comparator;
    }

    @Override
    public ExampleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        final ItemExampleBinding binding = ItemExampleBinding.inflate(inflater, parent, false);
        return new ExampleViewHolder(binding);
    }

    @Override
    public void onBindViewHolder(ExampleViewHolder holder, int position) {
        final ExampleModel model = mSortedList.get(position);
        holder.bind(model);
    }

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

The Comparator used to sort the item is passed in through the constructor so we can use the same Adapter even if the items are supposed to be displayed in a different order.

Now we are almost done! But we first need a way to add or remove items to the Adapter. For this purpose we can add methods to the Adapter which allow us to add and remove items to the SortedList:

public void add(ExampleModel model) {
    mSortedList.add(model);
}

public void remove(ExampleModel model) {
    mSortedList.remove(model);
}

public void add(List<ExampleModel> models) {
    mSortedList.addAll(models);
}

public void remove(List<ExampleModel> models) {
    mSortedList.beginBatchedUpdates();
    for (ExampleModel model : models) {
        mSortedList.remove(model);
    }
    mSortedList.endBatchedUpdates();
}

We don't need to call any notify methods here because the SortedList already does this for through the SortedList.Callback! Aside from that the implementation of these methods is pretty straight forward with one exception: the remove method which removes a List of models. Since the SortedList has only one remove method which can remove a single object we need to loop over the list and remove the models one by one. Calling beginBatchedUpdates() at the beginning batches all the changes we are going to make to the SortedList together and improves performance. When we call endBatchedUpdates() the RecyclerView is notified about all the changes at once.

Additionally what you have to understand is that if you add an object to the SortedList and it is already in the SortedList it won't be added again. Instead the SortedList uses the areContentsTheSame() method to figure out if the object has changed - and if it has the item in the RecyclerView will be updated.

Anyway, what I usually prefer is one method which allows me to replace all items in the RecyclerView at once. Remove everything which is not in the List and add all items which are missing from the SortedList:

public void replaceAll(List<ExampleModel> models) {
    mSortedList.beginBatchedUpdates();
    for (int i = mSortedList.size() - 1; i >= 0; i--) {
        final ExampleModel model = mSortedList.get(i);
        if (!models.contains(model)) {
            mSortedList.remove(model);
        }
    }
    mSortedList.addAll(models);
    mSortedList.endBatchedUpdates();
}

This method again batches all updates together to increase performance. The first loop is in reverse since removing an item at the start would mess up the indexes of all items that come up after it and this can lead in some instances to problems like data inconsistencies. After that we just add the List to the SortedList using addAll() to add all items which are not already in the SortedList and - just like I described above - update all items that are already in the SortedList but have changed.

And with that the Adapter is complete. The whole thing should look something like this:

public class ExampleAdapter extends RecyclerView.Adapter<ExampleViewHolder> {

    private final SortedList<ExampleModel> mSortedList = new SortedList<>(ExampleModel.class, new SortedList.Callback<ExampleModel>() {
        @Override
        public int compare(ExampleModel a, ExampleModel b) {
            return mComparator.compare(a, b);
        }

        @Override
        public void onInserted(int position, int count) {
            notifyItemRangeInserted(position, count);
        }

        @Override
        public void onRemoved(int position, int count) {
            notifyItemRangeRemoved(position, count);
        }

        @Override
        public void onMoved(int fromPosition, int toPosition) {
            notifyItemMoved(fromPosition, toPosition);
        }

        @Override
        public void onChanged(int position, int count) {
            notifyItemRangeChanged(position, count);
        }

        @Override
        public boolean areContentsTheSame(ExampleModel oldItem, ExampleModel newItem) {
            return oldItem.equals(newItem);
        }

        @Override
        public boolean areItemsTheSame(ExampleModel item1, ExampleModel item2) {
            return item1 == item2;
        }
    });

    private final Comparator<ExampleModel> mComparator;
    private final LayoutInflater mInflater;

    public ExampleAdapter(Context context, Comparator<ExampleModel> comparator) {
        mInflater = LayoutInflater.from(context);
        mComparator = comparator;
    }

    @Override
    public ExampleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        final ItemExampleBinding binding = ItemExampleBinding.inflate(mInflater, parent, false);
        return new ExampleViewHolder(binding);
    }

    @Override
    public void onBindViewHolder(ExampleViewHolder holder, int position) {
        final ExampleModel model = mSortedList.get(position);
        holder.bind(model);
    }

    public void add(ExampleModel model) {
        mSortedList.add(model);
    }

    public void remove(ExampleModel model) {
        mSortedList.remove(model);
    }

    public void add(List<ExampleModel> models) {
        mSortedList.addAll(models);
    }

    public void remove(List<ExampleModel> models) {
        mSortedList.beginBatchedUpdates();
        for (ExampleModel model : models) {
            mSortedList.remove(model);
        }
        mSortedList.endBatchedUpdates();
    }

    public void replaceAll(List<ExampleModel> models) {
        mSortedList.beginBatchedUpdates();
        for (int i = mSortedList.size() - 1; i >= 0; i--) {
            final ExampleModel model = mSortedList.get(i);
            if (!models.contains(model)) {
                mSortedList.remove(model);
            }
        }
        mSortedList.addAll(models);
        mSortedList.endBatchedUpdates();
    }

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

The only thing missing now is to implement the filtering!


Implementing the filter logic

To implement the filter logic we first have to define a List of all possible models. For this example I create a List of ExampleModel instances from an array of movies:

private static final String[] MOVIES = new String[]{
        ...
};

private static final Comparator<ExampleModel> ALPHABETICAL_COMPARATOR = new Comparator<ExampleModel>() {
    @Override
    public int compare(ExampleModel a, ExampleModel b) {
        return a.getText().compareTo(b.getText());
    }
};

private ExampleAdapter mAdapter;
private List<ExampleModel> mModels;
private RecyclerView mRecyclerView;

    @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mBinding = DataBindingUtil.setContentView(this, R.layout.activity_main);

    mAdapter = new ExampleAdapter(this, ALPHABETICAL_COMPARATOR);

    mBinding.recyclerView.setLayoutManager(new LinearLayoutManager(this));
    mBinding.recyclerView.setAdapter(mAdapter);

    mModels = new ArrayList<>();
    for (String movie : MOVIES) {
        mModels.add(new ExampleModel(movie));
    }
    mAdapter.add(mModels);
}

Nothing special going on here, we just instantiate the Adapter and set it to the RecyclerView. After that we create a List of models from the movie names in the MOVIES array. Then we add all the models to the SortedList.

Now we can go back to onQueryTextChange() which we defined earlier and start implementing the filter logic:

@Override
public boolean onQueryTextChange(String query) {
    final List<ExampleModel> filteredModelList = filter(mModels, query);
    mAdapter.replaceAll(filteredModelList);
    mBinding.recyclerView.scrollToPosition(0);
    return true;
}

This is again pretty straight forward. We call the method filter() and pass in the List of ExampleModels as well as the query string. We then call replaceAll() on the Adapter and pass in the filtered List returned by filter(). We also have to call scrollToPosition(0) on the RecyclerView to ensure that the user can always see all items when searching for something. Otherwise the RecyclerView might stay in a scrolled down position while filtering and subsequently hide a few items. Scrolling to the top ensures a better user experience while searching.

The only thing left to do now is to implement filter() itself:

private static List<ExampleModel> filter(List<ExampleModel> models, String query) {
    final String lowerCaseQuery = query.toLowerCase();

    final List<ExampleModel> filteredModelList = new ArrayList<>();
    for (ExampleModel model : models) {
        final String text = model.getText().toLowerCase();
        if (text.contains(lowerCaseQuery)) {
            filteredModelList.add(model);
        }
    }
    return filteredModelList;
}

The first thing we do here is call toLowerCase() on the query string. We don't want our search function to be case sensitive and by calling toLowerCase() on all strings we compare we can ensure that we return the same results regardless of case. It then just iterates through all the models in the List we passed into it and checks if the query string is contained in the text of the model. If it is then the model is added to the filtered List.

And that's it! The above code will run on API level 7 and above and starting with API level 11 you get item animations for free!

I realize that this is a very detailed description which probably makes this whole thing seem more complicated than it really is, but there is a way we can generalize this whole problem and make implementing an Adapter based on a SortedList much simpler.


Generalizing the problem and simplifying the Adapter

In this section I am not going to go into much detail - partly because I am running up against the character limit for answers on Stack Overflow but also because most of it already explained above - but to summarize the changes: We can implemented a base Adapter class which already takes care of dealing with the SortedList as well as binding models to ViewHolder instances and provides a convenient way to implement an Adapter based on a SortedList. For that we have to do two things:

  • We need to create a ViewModel interface which all model classes have to implement
  • We need to create a ViewHolder subclass which defines a bind() method the Adapter can use to bind models automatically.

This allows us to just focus on the content which is supposed to be displayed in the RecyclerView by just implementing the models and there corresponding ViewHolder implementations. Using this base class we don't have to worry about the intricate details of the Adapter and its SortedList.

SortedListAdapter

Because of the character limit for answers on StackOverflow I can't go through each step of implementing this base class or even add the full source code here, but you can find the full source code of this base class - I called it SortedListAdapter - in this GitHub Gist.

To make your life simple I have published a library on jCenter which contains the SortedListAdapter! If you want to use it then all you need to do is add this dependency to your app's build.gradle file:

compile 'com.github.wrdlbrnft:sorted-list-adapter:0.2.0.1'

You can find more information about this library on the library homepage.

Using the SortedListAdapter

To use the SortedListAdapter we have to make two changes:

  • Change the ViewHolder so that it extends SortedListAdapter.ViewHolder. The type parameter should be the model which should be bound to this ViewHolder - in this case ExampleModel. You have to bind data to your models in performBind() instead of bind().

    public class ExampleViewHolder extends SortedListAdapter.ViewHolder<ExampleModel> {
    
        private final ItemExampleBinding mBinding;
    
        public ExampleViewHolder(ItemExampleBinding binding) {
            super(binding.getRoot());
            mBinding = binding;
        }
    
        @Override
        protected void performBind(ExampleModel item) {
            mBinding.setModel(item);
        }
    }
    
  • Make sure that all your models implement the ViewModel interface:

    public class ExampleModel implements SortedListAdapter.ViewModel {
        ...
    }
    

After that we just have to update the ExampleAdapter to extend SortedListAdapter and remove everything we don't need anymore. The type parameter should be the type of model you are working with - in this case ExampleModel. But if you are working with different types of models then set the type parameter to ViewModel.

public class ExampleAdapter extends SortedListAdapter<ExampleModel> {

    public ExampleAdapter(Context context, Comparator<ExampleModel> comparator) {
        super(context, ExampleModel.class, comparator);
    }

    @Override
    protected ViewHolder<? extends ExampleModel> onCreateViewHolder(LayoutInflater inflater, ViewGroup parent, int viewType) {
        final ItemExampleBinding binding = ItemExampleBinding.inflate(inflater, parent, false);
        return new ExampleViewHolder(binding);
    }

    @Override
    protected boolean areItemsTheSame(ExampleModel item1, ExampleModel item2) {
        return item1.getId() == item2.getId();
    }

    @Override
    protected boolean areItemContentsTheSame(ExampleModel oldItem, ExampleModel newItem) {
        return oldItem.equals(newItem);
    }
}

After that we are done! However one last thing to mention: The SortedListAdapter does not have the same add(), remove() or replaceAll() methods our original ExampleAdapter had. It uses a separate Editor object to modify the items in the list which can be accessed through the edit() method. So if you want to remove or add items you have to call edit() then add and remove the items on this Editor instance and once you are done, call commit() on it to apply the changes to the SortedList:

mAdapter.edit()
        .remove(modelToRemove)
        .add(listOfModelsToAdd)
        .commit();

All changes you make this way are batched together to increase performance. The replaceAll() method we implemented in the chapters above is also present on this Editor object:

mAdapter.edit()
        .replaceAll(mModels)
        .commit();

If you forget to call commit() then none of your changes will be applied!

A potentially dangerous Request.Form value was detected from the client

It seems no one has mentioned the below yet, but it fixes the issue for me. And before anyone says yeah it's Visual Basic... yuck.

<%@ Page Language="vb" AutoEventWireup="false" CodeBehind="Example.aspx.vb" Inherits="Example.Example" **ValidateRequest="false"** %>

I don't know if there are any downsides, but for me this worked amazing.

IndexError: too many indices for array

I think the problem is given in the error message, although it is not very easy to spot:

IndexError: too many indices for array
xs  = data[:, col["l1"     ]]

'Too many indices' means you've given too many index values. You've given 2 values as you're expecting data to be a 2D array. Numpy is complaining because data is not 2D (it's either 1D or None).

This is a bit of a guess - I wonder if one of the filenames you pass to loadfile() points to an empty file, or a badly formatted one? If so, you might get an array returned that is either 1D, or even empty (np.array(None) does not throw an Error, so you would never know...). If you want to guard against this failure, you can insert some error checking into your loadfile function.

I highly recommend in your for loop inserting:

print(data)

This will work in Python 2.x or 3.x and might reveal the source of the issue. You might well find it is only one value of your outputs_l1 list (i.e. one file) that is giving the issue.

How do I pass JavaScript variables to PHP?

We can easily pass values even on same/ different pages using the cookies shown in the code as follows (In my case, I'm using it with facebook integration) -

function statusChangeCallback(response) {
    console.log('statusChangeCallback');
    if (response.status === 'connected') {
        // Logged into your app and Facebook.
        FB.api('/me?fields=id,first_name,last_name,email', function (result) {
            document.cookie = "fbdata = " + result.id + "," + result.first_name + "," + result.last_name + "," + result.email;
            console.log(document.cookie);
        });
    }
}

And I've accessed it (in any file) using -

<?php 
    if(isset($_COOKIE['fbdata'])) { 
        echo "welcome ".$_COOKIE['fbdata'];
    }
?>

strange error in my Animation Drawable

Looks like whatever is in your Animation Drawable definition is too much memory to decode and sequence. The idea is that it loads up all the items and make them in an array and swaps them in and out of the scene according to the timing specified for each frame.

If this all can't fit into memory, it's probably better to either do this on your own with some sort of handler or better yet just encode a movie with the specified frames at the corresponding images and play the animation through a video codec.

Add image to layout in ruby on rails

image_tag is the best way to do the job friend

How to sort a List of objects by their date (java collections, List<Object>)

In Java 8, it's now as simple as:

movieItems.sort(Comparator.comparing(Movie::getDate));

Dynamically update values of a chartjs chart

Showing realtime update chartJS

function add_data(chart, label, data) 
      {
        var today = new Date();
        var time = today.getHours() + ":" + today.getMinutes() + ":" + today.getSeconds();
        myLineChart.data.datasets[0].data.push(Math.random() * 100);
        myLineChart.data.datasets[1].data.push(Math.random() * 100);
        myLineChart.data.labels.push(time)
        myLineChart.update();
      }
      setInterval(add_data, 10000); //milisecond

full code , you can download in description link

When use getOne and findOne methods Spring Data JPA

The getOne methods returns only the reference from DB (lazy loading). So basically you are outside the transaction (the Transactional you have been declare in service class is not considered), and the error occur.

Check if Internet Connection Exists with jQuery?

Sending XHR requests is bad because it could fail if that particular server is down. Instead, use googles API library to load their cached version(s) of jQuery.

You can use googles API to perform a callback after loading jQuery, and this will check if jQuery was loaded successfully. Something like the code below should work:

<script type="text/javascript">
    google.load("jquery");

    // Call this function when the page has been loaded
    function test_connection() {
        if($){
            //jQuery WAS loaded.
        } else {
            //jQuery failed to load.  Grab the local copy.
        }
    }
    google.setOnLoadCallback(test_connection);
</script>

The google API documentation can be found here.

Java 8 stream map to list of keys sorted by values

You have to sort with a custom comparator based on the value of the entry. Then select all the keys before collecting

countByType.entrySet()
           .stream()
           .sorted((e1, e2) -> e1.getValue().compareTo(e2.getValue())) // custom Comparator
           .map(e -> e.getKey())
           .collect(Collectors.toList());

laravel 5.5 The page has expired due to inactivity. Please refresh and try again

In my case the same problem was caused because I forgot to add > at the end of my hidden input field, like so: <input type="hidden" name="_token" value="{{ Session::token() }}"

So, I fixed it by adding it:

<input type="hidden" name="_token" value="{{ Session::token() }}">

Postgres and Indexes on Foreign Keys and Primary Keys

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

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

The documentation on unique indexes says:

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

and the documentation on constraints says:

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

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

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

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

How can I convert uppercase letters to lowercase in Notepad++

Ctrl+A , Ctrl+Shift+U

should do the trick!

Edit: Ctrl+U is the shortcut to be used to convert capital letters to lowercase (reverse scenario)

What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?

As usual, there are concurrency--overhead--speed tradeoffs involved. You really need to consider the detailed concurrency requirements of your application to make a decision, and then test your code to see if it's good enough.

Executing <script> elements inserted with .innerHTML

@phidah... Here is a very interesting solution to your problem: http://24ways.org/2005/have-your-dom-and-script-it-too

So it would look like this instead:

<img src="empty.gif" onload="alert('test');this.parentNode.removeChild(this);" />

Smooth scrolling with just pure css

You can do this with pure CSS but you will need to hard code the offset scroll amounts, which may not be ideal should you be changing page content- or should dimensions of your content change on say window resize.

You're likely best placed to use e.g. jQuery, specifically:

$('html, body').stop().animate({
   scrollTop: element.offset().top
}, 1000);

A complete implementation may be:

$('#up, #down').on('click', function(e){
    e.preventDefault();
    var target= $(this).get(0).id == 'up' ? $('#down') : $('#up');
    $('html, body').stop().animate({
       scrollTop: target.offset().top
    }, 1000);
});

Where element is the target element to scroll to and 1000 is the delay in ms before completion.

Demo Fiddle

The benefit being, no matter what changes to your content dimensions, the function will not need to be altered.

git replacing LF with CRLF

Removing the below from the ~/.gitattributes file

* text=auto

will prevent git from checking line-endings in the first-place.

How can I convert a PFX certificate file for use with Apache on a linux server?

To get it to work with Apache, we needed one extra step.

openssl pkcs12 -in domain.pfx -clcerts -nokeys -out domain.cer
openssl pkcs12 -in domain.pfx -nocerts -nodes  -out domain_encrypted.key
openssl rsa -in domain_encrypted.key -out domain.key

The final command decrypts the key for use with Apache. The domain.key file should look like this:

-----BEGIN RSA PRIVATE KEY-----
MjQxODIwNTFaMIG0MRQwEgYDVQQKEwtFbnRydXN0Lm5ldDFAMD4GA1UECxQ3d3d3
LmVudHJ1c3QubmV0L0NQU18yMDQ4IGluY29ycC4gYnkgcmVmLiAobGltaXRzIGxp
YWIuKTElMCMGA1UECxMcKGMpIDE5OTkgRW50cnVzdC5uZXQgTGltaXRlZDEzMDEG
A1UEAxMqRW50cnVzdC5uZXQgQ2VydGlmaWNhdGlvbiBBdXRob3JpdHkgKDIwNDgp
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEArU1LqRKGsuqjIAcVFmQq
-----END RSA PRIVATE KEY-----

Url to a google maps page to show a pin given a latitude / longitude?

You should be able to do something like this:

http://maps.google.com/maps?q=24.197611,120.780512

Some more info on the query parameters available at this location

Here's another link to an SO thread

MVC3 EditorFor readOnly

For those who wonder why you want to use an EditoFor if you don`t want it to be editable, I have an example.

I have this in my Model.

    [DataType(DataType.Date)]
    [DisplayFormat(ApplyFormatInEditMode = true, DataFormatString = "{0: dd/MM/yyyy}")]
    public DateTime issueDate { get; set; }

and when you want to display that format, the only way it works is with an EditorFor, but I have a jquery datepicker for that "input" so it has to be readonly to avoid the users of writting down wrong dates.

To make it work the way I want I put this in the View...

     @Html.EditorFor(m => m.issueDate, new{ @class="inp", @style="width:200px", @MaxLength = "200"})

and this in my ready function...

     $('#issueDate').prop('readOnly', true);

I hope this would be helpful for someone out there. Sorry for my English

Bootstrap NavBar with left, center or right aligned items

2021 Update

Bootstrap 5 (beta)

Bootstrap 5 also has a flexbox Navbar, and introduces new RTL support. For this reason the concept of "left" and "right" has been replaced with "start" and "end". Therefore the margin utilities changed for Bootstrap 5 beta:

  • ml-auto => ms-auto
  • mr-auto => me-auto

Bootstrap 4

Now that Bootstrap 4 has flexbox, Navbar alignment is much easier. Here are updated examples for left, right and center in the Bootstrap 4 Navbar, and many other alignment scenarios demonstrated here.

The flexbox, auto-margins, and ordering utility classes can be used to align Navbar content as needed. There are many things to consider including the order and alignment of Navbar items (brand, links, toggler) on both large screens and the mobile/collapsed views. Don't use the grid classes (row,col) for the Navbar.

Here are various examples...

Left, center(brand) and right links:

enter image description here

<nav class="navbar navbar-expand-md navbar-dark bg-dark">
    <div class="navbar-collapse collapse w-100 order-1 order-md-0 dual-collapse2">
        <ul class="navbar-nav mr-auto">
            <li class="nav-item active">
                <a class="nav-link" href="#">Left</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="//codeply.com">Codeply</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Link</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Link</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Link</a>
            </li>
        </ul>
    </div>
    <div class="mx-auto order-0">
        <a class="navbar-brand mx-auto" href="#">Navbar 2</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target=".dual-collapse2">
            <span class="navbar-toggler-icon"></span>
        </button>
    </div>
    <div class="navbar-collapse collapse w-100 order-3 dual-collapse2">
        <ul class="navbar-nav ml-auto">
            <li class="nav-item">
                <a class="nav-link" href="#">Right</a>
            </li>
            <li class="nav-item">
                <a class="nav-link" href="#">Link</a>
            </li>
        </ul>
    </div>
</nav>

http://codeply.com/go/qhaBrcWp3v


Another BS4 Navbar option with center links and overlay logo image:

center links and overlay logo image

<nav class="navbar navbar-expand-lg navbar-dark bg-dark">
    <div class="navbar-collapse collapse w-100 dual-collapse2 order-1 order-md-0">
        <ul class="navbar-nav ml-auto text-center">
            <li class="nav-item active">
                <a class="nav-link" href="#">Link</a>
            </li>
        </ul>
    </div>
    <div class="mx-auto my-2 order-0 order-md-1 position-relative">
        <a class="mx-auto" href="#">
            <img src="//placehold.it/120/ccff00" class="rounded-circle">
        </a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target=".dual-collapse2">
            <span class="navbar-toggler-icon"></span>
        </button>
    </div>
    <div class="navbar-collapse collapse w-100 dual-collapse2 order-2 order-md-2">
        <ul class="navbar-nav mr-auto text-center">
            <li class="nav-item">
                <a class="nav-link" href="#">Link</a>
            </li>
        </ul>
    </div>
</nav>

Or, these other Bootstrap 4 alignment scenarios:

brand left, dead center links, (empty right)

Navbar brand left, dead center links


brand and links center, icons left and right

enter image description here


More Bootstrap 4 examples:

toggler left on mobile, brand right
center brand and links on mobile
right align links on desktop, center links on mobile
left links & toggler, center brand, search right


Also see: Bootstrap 4 align navbar items to the right
Bootstrap 4 navbar right align with button that doesn't collapse on mobile
Center an element in Bootstrap 4 Navbar


Bootstrap 3

Option 1 - Brand center, with left/right nav links:

enter image description here

<nav class="navbar navbar-default" role="navigation">
  <div class="navbar-header">
    <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
    </button>    
  </div>
  <a class="navbar-brand" href="#">Brand</a>
  <div class="navbar-collapse collapse">
    <ul class="nav navbar-nav navbar-left">
        <li><a href="#">Left</a></li>
        <li><a href="#about">Left</a></li>
    </ul>
    <ul class="nav navbar-nav navbar-right">
      <li><a href="#about">Right</a></li>
      <li><a href="#contact">Right</a></li>
    </ul>
  </div>
</nav>

.navbar-brand
{
    position: absolute;
    width: 100%;
    left: 0;
    text-align: center;
    margin:0 auto;
}
.navbar-toggle {
    z-index:3;
}

http://bootply.com/98314 (3.x)


Option 2 - Left, center and right nav links:

enter image description here

<nav class="navbar navbar-default" role="navigation">
  <div class="navbar-header">
    <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
    </button>    
  </div>
  <div class="navbar-collapse collapse">
    <ul class="nav navbar-nav">
        <li><a href="#">Left</a></li>
    </ul>
    <ul class="nav navbar-nav navbar-center">
        <li><a href="#">Center</a></li>
        <li><a href="#">Center</a></li>
      <li><a href="#">Center</a></li>
    </ul>
    <ul class="nav navbar-nav navbar-right">
        <li><a href="#">Right</a></li>
    </ul>
  </div>
</nav>

@media (min-width: 768px) {
  .navbar-nav.navbar-center {
    position: absolute;
    left: 50%;
    transform: translatex(-50%);
  }
}

http://bootply.com/SGYC6BWeBK

Option 3 - Center both brand and links

enter image description here

.navbar .navbar-header,
.navbar-collapse {
    float:none;
    display:inline-block;
    vertical-align: top;
}

@media (max-width: 768px) {
    .navbar-collapse  {
        display: block;
    }
}

http://codeply.com/go/1lrdvNH9GI

More examples:

Left brand, center links
Left toggler, center brand

For 3.x also see nav-justified: Bootstrap center navbar


Center Navbar in Bootstrap
Bootstrap 4 align navbar items to the right

Git SSH error: "Connect to host: Bad file number"

In my case the IP address of our git host had changed.

Simply flushing the DNS cache fixed the problem.

Bootstrap navbar Active State not working

I had to go a step forward because my file names were not the same as my nav bar titles. i.e. my first nav bar link was HOME but the file name is index..

So just grab the pathname and match it.

Obviously this is a crude example and could be more efficient but it is highly custom need.

var loc_path = location.pathname;
$('li.active').removeClass('active');



if(loc_path.includes('index')){
    $('li :eq(0)').addClass('active');
}else if(loc_path.includes('blog')){
    $('li :eq(2)').addClass('active');
}else if(loc_path.includes('news')){
    $('li :eq(3)').addClass('active');
}else if(loc_path.includes('house')){
    $('li :eq(4)').addClass('active');
}

Chart won't update in Excel (2007)

I faced the same problem with my work last week when I added some more calculation to my sheet. After that, using radio buttons to select data to be presented on graphs did not update the graphs anymore.

The best explanation I have been able to find so far is this: http://support.microsoft.com/kb/243495

If I understood it right, if there are more than 65536 formulas that have another cell as a reference in your file, Excel starts to optimize the calculation and in some cases graphs don't update correctly anymore.

If there is a workaround for this without using VBA macros, I would be glad to hear that (can't use those as the files need to be shared through SharePoint without VBA macros).

ASP.NET Identity reset password

In current release

Assuming you have handled the verification of the request to reset the forgotten password, use following code as a sample code steps.

ApplicationDbContext =new ApplicationDbContext()
String userId = "<YourLogicAssignsRequestedUserId>";
String newPassword = "<PasswordAsTypedByUser>";
ApplicationUser cUser = UserManager.FindById(userId);
String hashedNewPassword = UserManager.PasswordHasher.HashPassword(newPassword);
UserStore<ApplicationUser> store = new UserStore<ApplicationUser>();            
store.SetPasswordHashAsync(cUser, hashedNewPassword);

In AspNet Nightly Build

The framework is updated to work with Token for handling requests like ForgetPassword. Once in release, simple code guidance is expected.

Update:

This update is just to provide more clear steps.

ApplicationDbContext context = new ApplicationDbContext();
UserStore<ApplicationUser> store = new UserStore<ApplicationUser>(context);
UserManager<ApplicationUser> UserManager = new UserManager<ApplicationUser>(store);
String userId = User.Identity.GetUserId();//"<YourLogicAssignsRequestedUserId>";
String newPassword = "test@123"; //"<PasswordAsTypedByUser>";
String hashedNewPassword = UserManager.PasswordHasher.HashPassword(newPassword);                    
ApplicationUser cUser = await store.FindByIdAsync(userId);
await store.SetPasswordHashAsync(cUser, hashedNewPassword);
await store.UpdateAsync(cUser);

Algorithm to find Largest prime factor of a number

It seems to me that step #2 of the algorithm given isn't going to be all that efficient an approach. You have no reasonable expectation that it is prime.

Also, the previous answer suggesting the Sieve of Eratosthenes is utterly wrong. I just wrote two programs to factor 123456789. One was based on the Sieve, one was based on the following:

1)  Test = 2 
2)  Current = Number to test 
3)  If Current Mod Test = 0 then  
3a)     Current = Current Div Test 
3b)     Largest = Test
3c)     Goto 3. 
4)  Inc(Test) 
5)  If Current < Test goto 4
6)  Return Largest

This version was 90x faster than the Sieve.

The thing is, on modern processors the type of operation matters far less than the number of operations, not to mention that the algorithm above can run in cache, the Sieve can't. The Sieve uses a lot of operations striking out all the composite numbers.

Note, also, that my dividing out factors as they are identified reduces the space that must be tested.

Laravel Migration table already exists, but I want to add new not the older

You can delete all the tables but it will be not a good practice, instead try this command

php artisan migrate:fresh

Make sure to use the naming convention correctly. I have tested this in version laravel 5.7 It is important to not try this command when your site is on server because it drops all information.

How to get logged-in user's name in Access vba?

Try this:

Function UserNameWindows() As String
     UserName = Environ("USERNAME")
End Function

How to get the dimensions of a tensor (in TensorFlow) at graph construction time?

I see most people confused about tf.shape(tensor) and tensor.get_shape() Let's make it clear:

  1. tf.shape

tf.shape is used for dynamic shape. If your tensor's shape is changable, use it. An example: a input is an image with changable width and height, we want resize it to half of its size, then we can write something like:
new_height = tf.shape(image)[0] / 2

  1. tensor.get_shape

tensor.get_shape is used for fixed shapes, which means the tensor's shape can be deduced in the graph.

Conclusion: tf.shape can be used almost anywhere, but t.get_shape only for shapes can be deduced from graph.

Find records with a date field in the last 24 hours

SELECT * FROM news WHERE date < DATEADD(Day, -1, date)

Recommended SQL database design for tags or tagging

Use a single formatted text column[1] for storing the tags and use a capable full text search engine to index this. Else you will run into scaling problems when trying to implement boolean queries.

If you need details about the tags you have, you can either keep track of it in a incrementally maintained table or run a batch job to extract the information.

[1] Some RDBMS even provide a native array type which might be even better suited for storage by not needing a parsing step, but might cause problems with the full text search.

Get absolute path to workspace directory in Jenkins Pipeline plugin

For me WORKSPACE was a valid property of the pipeline itself. So when I handed over this to a Groovy method as parameter context from the pipeline script itself, I was able to access the correct value using "... ${context.WORKSPACE} ..."

(on Jenkins 2.222.3, Build Pipeline Plugin 1.5.8, Pipeline: Nodes and Processes 2.35)

npm install error - unable to get local issuer certificate

There is an issue discussed here which talks about using ca files, but it's a bit beyond my understanding and I'm unsure what to do about it.

This isn't too difficult once you know how! For Windows:

Using Chrome go to the root URL NPM is complaining about (so https://raw.githubusercontent.com in your case). Open up dev tools and go to Security-> View Certificate. Check Certification path and make sure your at the top level certificate, if not open that one. Now go to "Details" and export the cert with "Copy to File...".

You need to convert this from DER to PEM. There are several ways to do this, but the easiest way I found was an online tool which should be easy to find with relevant keywords.

Now if you open the key with your favorite text editor you should see

-----BEGIN CERTIFICATE----- 

yourkey

-----END CERTIFICATE-----

This is the format you need. You can do this for as many keys as you need, and combine them all into one file. I had to do github and the npm registry keys in my case.

Now just edit your .npmrc to point to the file containing your keys like so

cafile=C:\workspace\rootCerts.crt

I have personally found this to perform significantly better behind our corporate proxy as opposed to the strict-ssl option. YMMV.

how to set select element as readonly ('disabled' doesnt pass select value on server)

You can simulate a readonly select box using the CSS pointer-events property:

select[readonly]
{
    pointer-events: none;
}

The HTML tabindex property will also prevent it from being selected by keyboard tabbing:

<select tabindex="-1">

_x000D_
_x000D_
select[readonly]_x000D_
{_x000D_
    pointer-events: none;_x000D_
}_x000D_
_x000D_
_x000D_
/* irrelevent styling */_x000D_
_x000D_
*_x000D_
{_x000D_
  box-sizing: border-box;_x000D_
}_x000D_
_x000D_
*[readonly]_x000D_
{_x000D_
  background: #fafafa;_x000D_
  border: 1px solid #ccc;_x000D_
  color: #555;_x000D_
}_x000D_
_x000D_
input, select_x000D_
{_x000D_
  display:block;_x000D_
  width: 20rem;_x000D_
  padding: 0.5rem;_x000D_
  margin-bottom: 1rem;_x000D_
}
_x000D_
<form>_x000D_
  <input type="text" value="this is a normal text box">_x000D_
  <input type="text" readonly value="this is a readonly text box">_x000D_
  <select readonly tabindex="-1">_x000D_
    <option>This is a readonly select box</option>_x000D_
    <option>Option 2</option>_x000D_
  </select>_x000D_
  <select>_x000D_
    <option>This is a normal select box</option>_x000D_
    <option>Option 2</option>_x000D_
  </select>_x000D_
</form>
_x000D_
_x000D_
_x000D_

Download file of any type in Asp.Net MVC using FileResult?

Thanks to Ian Henry!

In case if you need to get file from MS SQL Server here is the solution.

public FileResult DownloadDocument(string id)
        {
            if (!string.IsNullOrEmpty(id))
            {
                try
                {
                    var fileId = Guid.Parse(id);

                    var myFile = AppModel.MyFiles.SingleOrDefault(x => x.Id == fileId);

                    if (myFile != null)
                    {
                        byte[] fileBytes = myFile.FileData;
                        return File(fileBytes, System.Net.Mime.MediaTypeNames.Application.Octet, myFile.FileName);
                    }
                }
                catch
                {
                }
            }

            return null;
        }

Where AppModel is EntityFramework model and MyFiles presents table in your database. FileData is varbinary(MAX) in MyFiles table.

How can I prevent the textarea from stretching beyond his parent DIV element? (google-chrome issue only)

I'm hoping you are having the same problem that I had... my issue was simple: Make a fixed textarea with locked percentages inside the container (I'm new to CSS/JS/HTML, so bear with me, if I don't get the lingo correct) so that no matter the device it's displaying on, the box filling the container (the table cell) takes up the correct amount of space. Here's how I solved it:

<table width=100%>
    <tr class="idbbs">
        B.S.:
    </tr></br>
    <tr>
        <textarea id="bsinpt"></textarea>
    </tr>
</table>

Then CSS Looks like this...

#bsinpt
{
    color: gainsboro;
    float: none;
    background: black;
    text-align: left;
    font-family: "Helvetica", "Tahoma", "Verdana", "Arial Black", sans-serif;
    font-size: 100%;
  position: absolute;
  min-height: 60%;
  min-width: 88%;
  max-height: 60%;
  max-width: 88%;
  resize: none;
    border-top-color: lightsteelblue;
    border-top-width: 1px;
    border-left-color: lightsteelblue;
    border-left-width: 1px;
    border-right-color: lightsteelblue;
    border-right-width: 1px;
    border-bottom-color: lightsteelblue;
    border-bottom-width: 1px;
}

Sorry for the sloppy code block here, but I had to show you what's important and I don't know how to insert quoted CSS code on this website. In any case, to ensure you see what I'm talking about, the important CSS is less indented here...

What I then did (as shown here) is very specifically tweak the percentages until I found the ones that worked perfectly to fit display, no matter what device screen is used.

Granted, I think the "resize: none;" is overkill, but better safe than sorry and now the consumers will not have anyway to resize the box, nor will it matter what device they are viewing it from.

It works great.

what is the use of $this->uri->segment(3) in codeigniter pagination

Let's say you have a url like this http://www.example.com/controller/action/arg1/arg2

If you want to know what are the arguments that are being passed in this url

$param_offset=0;
$params = array_slice($this->uri->rsegment_array(), $param_offset);
var_dump($params);

Output will be:

array (size=2)
  0 => string 'arg1'
  1 => string 'arg2'

Difference in boto3 between resource, client, and session?

I'll try and explain it as simple as possible. So there is no guarantee of the accuracy of the actual terms.

Session is where to initiate the connectivity to AWS services. E.g. following is default session that uses the default credential profile(e.g. ~/.aws/credentials, or assume your EC2 using IAM instance profile )

sqs = boto3.client('sqs')
s3 = boto3.resource('s3')

Because default session is limit to the profile or instance profile used, sometimes you need to use the custom session to override the default session configuration (e.g. region_name, endpoint_url, etc. ) e.g.

# custom resource session must use boto3.Session to do the override
my_west_session = boto3.Session(region_name = 'us-west-2')
my_east_session = boto3.Session(region_name = 'us-east-1')
backup_s3 = my_west_session.resource('s3')
video_s3 = my_east_session.resource('s3')

# you have two choices of create custom client session. 
backup_s3c = my_west_session.client('s3')
video_s3c = boto3.client("s3", region_name = 'us-east-1')

Resource : This is the high-level service class recommended to be used. This allows you to tied particular AWS resources and passes it along, so you just use this abstraction than worry which target services are pointed to. As you notice from the session part, if you have a custom session, you just pass this abstract object than worrying about all custom regions,etc to pass along. Following is a complicated example E.g.

import boto3 
my_west_session = boto3.Session(region_name = 'us-west-2')
my_east_session = boto3.Session(region_name = 'us-east-1')
backup_s3 = my_west_session.resource("s3")
video_s3 = my_east_session.resource("s3")
backup_bucket = backup_s3.Bucket('backupbucket') 
video_bucket = video_s3.Bucket('videobucket')

# just pass the instantiated bucket object
def list_bucket_contents(bucket):
   for object in bucket.objects.all():
      print(object.key)

list_bucket_contents(backup_bucket)
list_bucket_contents(video_bucket)

Client is a low level class object. For each client call, you need to explicitly specify the targeting resources, the designated service target name must be pass long. You will lose the abstraction ability.

For example, if you only deal with the default session, this looks similar to boto3.resource.

import boto3 
s3 = boto3.client('s3')

def list_bucket_contents(bucket_name):
   for object in s3.list_objects_v2(Bucket=bucket_name) :
      print(object.key)

list_bucket_contents('Mybucket') 

However, if you want to list objects from a bucket in different regions, you need to specify the explicit bucket parameter required for the client.

import boto3 
backup_s3 = my_west_session.client('s3',region_name = 'us-west-2')
video_s3 = my_east_session.client('s3',region_name = 'us-east-1')

# you must pass boto3.Session.client and the bucket name 
def list_bucket_contents(s3session, bucket_name):
   response = s3session.list_objects_v2(Bucket=bucket_name)
   if 'Contents' in response:
     for obj in response['Contents']:
        print(obj['key'])

list_bucket_contents(backup_s3, 'backupbucket')
list_bucket_contents(video_s3 , 'videobucket') 

Unique device identification

It looks like the phoneGap plugin will allow you to get the device's uid.

http://docs.phonegap.com/en/3.0.0/cordova_device_device.md.html#device.uuid

Update: This is dependent on running native code. We used this solution writing javascript that was being compiled to native code for a native phone application we were creating.

Get filename in batch for loop

The answer by @AKX works on the command line, but not within a batch file. Within a batch file, you need an extra %, like this:

@echo off
for /R TutorialSteps %%F in (*.py) do echo %%~nF

Addition for BigDecimal

Just another example to add BigDecimals. Key point is that they are immutable and they can be initialized only in the constructor. Here is the code:

import java.util.*;
import java.math.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc;
        boolean first_right_number = false;
        BigDecimal initBigDecimal = BigDecimal.ZERO;
        BigDecimal add1 = BigDecimal.ZERO;
        BigDecimal add2 = BigDecimal.ZERO;

        while (!first_right_number)
        {
            System.out.print("Enter a first single numeric value: ");
            sc = new Scanner(System.in);
            if (sc.hasNextBigDecimal()) 
            {
                first_right_number = true;
                add1 = sc.nextBigDecimal();
            }
        }

        boolean second_right_number = false;
        while (!second_right_number)
        {
            System.out.print("Enter a second single numeric value: ");
            sc = new Scanner(System.in);
            if (sc.hasNextBigDecimal()) 
            {
                second_right_number = true;
                add2 = sc.nextBigDecimal();
            }
        }
        BigDecimal result = initBigDecimal.add(add1).add(add2);
        System.out.println("Sum of the 2 numbers is: " + result.toString());
    }
}

pip install from git repo branch

Instructions to install from private repo using ssh credentials:

$ pip install git+ssh://[email protected]/myuser/foo.git@my_version

Create or update mapping in elasticsearch

Generally speaking, you can update your index mapping using the put mapping api (reference here) :

curl -XPUT 'http://localhost:9200/advert_index/_mapping/advert_type' -d '
{
    "advert_type" : {
        "properties" : {

          //your new mapping properties

        }
    }
}
'

It's especially useful for adding new fields. However, in your case, you will try to change the location type, which will cause a conflict and prevent the new mapping from being used.

You could use the put mapping api to add another property containing the location as a lat/lon array, but you won't be able to update the previous location field itself.

Finally, you will have to reindex your data for your new mapping to be taken into account.

The best solution would really be to create a new index.

If your problem with creating another index is downtime, you should take a look at aliases to make things go smoothly.

How to break out of a loop in Bash?

while true ; do
    ...
    if [ something ]; then
        break
    fi
done

Regular Expressions: Is there an AND operator?

Use a non-consuming regular expression.

The typical (i.e. Perl/Java) notation is:

(?=expr)

This means "match expr but after that continue matching at the original match-point."

You can do as many of these as you want, and this will be an "and." Example:

(?=match this expression)(?=match this too)(?=oh, and this)

You can even add capture groups inside the non-consuming expressions if you need to save some of the data therein.

Change the color of a checked menu item in a navigation drawer

One need to set NavigateItem checked true whenever item in NavigateView is clicked

//listen for navigation events
NavigationView navigationView = (NavigationView)findViewById(R.id.navigation);
navigationView.setNavigationItemSelectedListener(this);
// select the correct nav menu item
navigationView.getMenu().findItem(mNavItemId).setChecked(true);

Add NavigationItemSelectedListener on NavigationView

  @Override
  public boolean onNavigationItemSelected(final MenuItem menuItem) {
    // update highlighted item in the navigation menu
    menuItem.setChecked(true);
    mNavItemId = menuItem.getItemId();

    // allow some time after closing the drawer before performing real navigation
    // so the user can see what is happening
    mDrawerLayout.closeDrawer(GravityCompat.START);
    mDrawerActionHandler.postDelayed(new Runnable() {
      @Override
      public void run() {
        navigate(menuItem.getItemId());
      }
    }, DRAWER_CLOSE_DELAY_MS);
    return true;
  }

CSS last-child selector: select last-element of specific class, not last child inside of parent?

if the last element type is article too, last-of-type will not work as expected.

maybe i not really understand how it work.

demo