ThreadJoinDemo

(1) // Java program to illustrate join() method in Java

import java.lang.*;

public class JoinDemo implements Runnable {

    public void run() {
        System.out.println("INSIDE Thread t run() .. Thread t starting.........................................................");
        try {
            System.out.println("Before sleep");
            Thread.sleep(5000);
            System.out.println("After sleep");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

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

        Thread t = new Thread(new JoinDemo());
        t.start();
        System.out.println("Thread t IS started...  ALIVE ?  " + t.isAlive());

      //  t.join();

        System.out.println("Thread t AT END ::******:: " +
                t.getName() +
                " ALIVE ?  " + t.isAlive());


    }
}

Output
-------

Thread t IS started...  ALIVE ?  true
INSIDE Thread t run() .. Thread t starting.........................................................
Before sleep
Thread t AT END ::******:: Thread-0 ALIVE ?  true
After sleep

-----------------------------------

(2)Add the  t.join(); and re-execute

t.join();

Output
-------

Thread t IS started...  ALIVE ?  true
INSIDE Thread t run() .. Thread t starting.........................................................
Before sleep
After sleep
Thread t AFTER JOIN ::******:: Thread-0 ALIVE ?  false

(3) Add the  t.join(milliseconds-after-which-join-will-nullify); and re-execute

t.join(1000);

Output
-------

Thread t IS started...  ALIVE ?  true
INSIDE Thread t run() .. Thread t starting.........................................................
Before sleep
Thread t AFTER JOIN ::******:: Thread-0 ALIVE ?  true
After sleep