How to count occurrences of a word in all the files of a directory?

grep -roh {WORD} {DIR_PATH} | wc -w

How to count all the lines of code in a directory recursively

find {DIR_PATH} -name 'FILE_NAME_WILDCARD' | xargs wc -l

Handling a RuntimeException in a Runnable (Thread)

 

package edu.test;

import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

public class App {

    public static void main(String[] args) throws ExecutionException, InterruptedException {
    ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();

    executor.scheduleAtFixedRate(new Runnable() {

        @Override
        public void run() {
        try {
            System.out.println(Thread.currentThread().getName() + " -> " + System.currentTimeMillis());
            throw new RuntimeException("exception");
        } catch (RuntimeException e) {
            Thread t = Thread.currentThread();
            t.getUncaughtExceptionHandler().uncaughtException(t, e);
        }
        }
    }, 0, 1000, TimeUnit.MILLISECONDS).get();

    System.out.println("exit");
    executor.shutdown();
    }
}

How to delete a remote git tag?

 git push --delete origin {tagname}

Submit a package in nexus with shell command line

curl --request PUT --user username:password nexusUrl/packageName --data-binary @packageName

ActiveMQ Network broker

To Start ActiveMq in network broker mode:


1- Configuration


$ cd $ACTIVEMQ_HOME/


$vi conf/activemq-dynamic-network-broker1.xml
--> add balise to this config file


$ cp conf/jetty.xml conf/jetty2.xml
$ vi conf/jetty.xml conf/jetty2.xml : update port number of jetty web server
$vi conf/activemq-dynamic-network-broker2.xml
--> add


2 - Developpement (producer and consumer)


- Create consumer:



package com.test.jms;


import javax.jms.Connection;
import javax.jms.Destination;
import javax.jms.ExceptionListener;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageListener;
import javax.jms.Session;


import org.apache.activemq.ActiveMQConnectionFactory;




public class JmsNetworkBrokerConsumer {

private static ActiveMQConnectionFactory connectionFactory;
private static Connection connection;
private static Session session;
private static Destination destination;
private static boolean transacted = false;
private static String brokerUrl = "failover:(tcp://localhost:61616,tcp://localhost:61618)"; 

public static void main(String ...strings) throws Exception{
connectionFactory = new ActiveMQConnectionFactory(brokerUrl);
connection = connectionFactory.createConnection();
connection.start();
session = connection.createSession(transacted, Session.AUTO_ACKNOWLEDGE);
destination = session.createQueue("common.queue");
MessageConsumer consumer = session.createConsumer(destination);
connection.setExceptionListener(new ExceptionListener() {

public void onException(JMSException exception) {
System.err.println("Error:" + exception);
}
});
consumer.setMessageListener(new MessageListener() {

public void onMessage(Message message) {
System.out.println("New Message : " + message);
}
});
}

}


- And now Create producer



package com.test.jms;


import javax.jms.Connection;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.Message;
import javax.jms.MessageProducer;
import javax.jms.Session;


import org.apache.activemq.ActiveMQConnectionFactory;


public class JmsNetworkBrokerProducer {   public static void main(String[] args) throws Exception
  {
    // Create the connection
    ActiveMQConnectionFactory connectionFactory = new ActiveMQConnectionFactory(null, null, "failover:(tcp://localhost:61616,tcp://localhost:61618)");
    Connection connection = connectionFactory.createConnection();
    connection.start();


    // Create the Session
    Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE);


    // And the Destination queue
    Destination destination = session.createQueue("common.queue");


    // Create the producer
    MessageProducer producer = session.createProducer(destination);
    producer.setDeliveryMode(DeliveryMode.PERSISTENT);
    Message m = session.createTextMessage("hello");


    //Send 3 messages at a time
    //for (int i = 0; i < 3; i++)
     //  producer.send(m);
    producer.send(m);


    //shutdown with NO Error handling
    connection.close();
 }
}

3- Start Servers

--> Start Server 1: 
- $ bin/activemq console xbean:conf/activemq-dynamic-network-broker1.xml
--> port activeMQ 61616, port jetty 8161


--> Start Server 2 : 
- $ bin/activemq console xbean:conf/activemq-dynamic-network-broker2.xml
--> port activeMQ 61618, port jetty 8162

4 - Start consumer : java JmsNetworkBrokerConsumer
5 - Start producer : java JmsNetworkBrokerProducer

empty linux cache script

empty-linux-cache.sh

#!/bin/bash

###################################################
### Script de purge du cache de la mémoire RAM  ###
###     Auteur: Jamel ESSOUSSI                  ###
###     email: jamel.essoussi@gmail.com         ###
###################################################

echo "Vidage du cache de la mémoire RAM"
echo "1" > /proc/sys/vm/drop_caches
sleep 5
echo "0" > /proc/sys/vm/drop_caches
echo "Vidage du cache terminé ;-)"

bash> chmod +x empty-linux-cache.sh
bash> sudo sh empty-linux-cache.sh