java | thread join and isalive method

java | thread join and isalive method

//Example  Use of isalive() and join() method

// join(): guranteed  that main thread terminates at last

class NewThread implements Runnable

{

String name;

Thread t;

NewThread(String n)

{

name=n;

t=new Thread(this,n);

System.out.println("thread name = "+t);

t.start();// start() calls run() method

}

public void run()//overrided method

{

try{

for(int i=0;i<=5;i++)

{

System.out.println(name +" i= "+i);

Thread.sleep(1000);//suspended for 2 seconds

}

}

catch(InterruptedException e)

{

System.out.println("child Thread interrupted ");

}

System.out.println(name+"Thread Exitting ");

}

}

class ThreadDemo

{

public static void  main(String ar[])//main is a thread which start very first

{

// creating three threads

Thread T =Thread.currentThread();   //T is object main thread

NewThread ob1=new NewThread("one");

NewThread ob2=new NewThread("two");

NewThread ob3=new NewThread("three");

System.out.println("Thread one is alive= "+ob1.t.isAlive());

System.out.println("Thread two is alive= "+ob2.t.isAlive());

System.out.println("Thread three is alive= "+ob3.t.isAlive());

//waiting for thread to be completed

try{

System.out.println("Waiting for threads to be finished");

ob1.t.join();

ob2.t.join();

ob3.t.join();

}

catch(InterruptedException e)

{

}

System.out.println("Thread one is alive= "+ob1.t.isAlive());

System.out.println("Thread two is alive= "+ob2.t.isAlive());

System.out.println("Thread three is alive= "+ob3.t.isAlive());

System.out.println("Main() Thread  is alive= "+T.isAlive());

System.out.println("Main Thread Exitting ");

}

}