code for replace null with quotes

https://gist.github.com/tureki/7af3ea2554eba60c34c5 $value = array(
	"deep"=>1,
	"data"=>null,
	"node"=>array(
	"deep"=>2,
	"data"=>null,
	"node"=>array(
	"deep"=>3
	)
	),
	null
	);
	array_walk_recursive($value, function (&$item, $key) {
	$item = null === $item ? '' : $item;
	});
	echo json_encode($value);

url regex validation

preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0-9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i", $url)

javascript tutorial

https://javascript.info/class

winston logger integration

https://thisdavej.com/using-winston-a-versatile-logging-library-for-node-js/

iterate java object ket and value

import java.lang.reflect.Field;

import java.lang.reflect.Modifier;

import java.util.HashMap;

import java.util.   ;

public class Main {

  private Main() {}

  public static Map<String, Object> getFieldNamesAndValues(final Object obj, boolean publicOnly)

    throws IllegalArgumentException,IllegalAccessException

  {

    Class<? extends Object> c1 = obj.getClass();

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

    Field[] fields = c1.getDeclaredFields();

    for (int i = 0; i < fields.length; i++) {

      String name = fields[i].getName();

      if (publicOnly) {

        if(Modifier.isPublic(fields[i].getModifiers())) {

          Object value = fields[i].get(obj);

          map.put(name, value);

        }

      }

      else {

        fields[i].setAccessible(true);

        Object value = fields[i].get(obj);

        map.put(name, value);

      }

    }

    return map;

  }

  /**

   * @param args

   */

  public static void main(String[] args) throws Exception {

    Dummy dummy = new Dummy();

    System.out.println(Main.getFieldNamesAndValues(dummy,true));

    System.out.println(Main.getFieldNamesAndValues(dummy,false));

    /*

     * output :

     *  {value3=43, value1=foo, value2=42}

     *  {value3=43, value4=bar, value1=foo, value2=42}

     */

  }

}

class Dummy {

  public String value1 = "foo";

  public int value2 = 42;

  public Integer value3 = new Integer(43);

  private String value4 = "bar";

}

duplicate class issue in netbens

https://stackoverflow.com/questions/19318704/java-duplicate-class

async await

https://hackernoon.com/6-reasons-why-javascripts-async-await-blows-promises-away-tutorial-c7ec10518dd9

git special command

check file difference 

git diff file_2.php

get date difference

https://stackoverflow.com/questions/13194322/php-regex-to-check-date-is-in-yyyy-mm-dd-format

$date="2012-09-12";

if (preg_match("/^[0-9]{4}-(0[1-9]|1[0-2])-(0[1-9]|[1-2][0-9]|3[0-1])$/",$date)) {
    return true;
} else {
    return false;
}

http://thisinterestsme.com/calculating-difference-dates-php/

<?php

 

//Our "then" date.

$then = "2009-02-04";

 

//Convert it into a timestamp.

$then = strtotime($then);

 

//Get the current timestamp.

$now = time();

 

//Calculate the difference.

$difference = $now - $then;

 

//Convert seconds into days.

$days = floor($difference / (60*60*24) );

 

echo $days;

jacson object mapper

https://www.baeldung.com/jackson-object-mapper-tutorial

password encryption in java

https://howtodoinjava.com/security/how-to-generate-secure-password-hash-md5-sha-pbkdf2-bcrypt-examples/