lockexample.java

import java.util.*;
import java.text.*;
import java.util.concurrent.locks.ReentrantLock;
public class lockexample {
    public static ReentrantLock thelock = new ReentrantLock();
    public static int i = 0;
    public static void main(String[] args)
    {
        new User( "Thread 1").start();
        new User( "Thread 2").start();
    }
}

class User extends Thread {
    private String name="";
    public User(String s){
        name=s;
    }
    @Override
    public void run()
    {
        lockexample.thelock.lock();
        try {
            for (int j=0;j<5;j++) {
                lockexample.i++;
                System.out.println("i="+lockexample.i+" thread "+name+ " Time= "+new SimpleDateFormat("yyyy.MM.dd.HH.mm.ss").format(new Date()));
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                }
            }
        } finally {
            lockexample.thelock.unlock();
        }
    }
}