THREADGROUP IN JAVA

Based on the functionality we can group threads as a single unit which is nothing but ThreadGroup. ThreadGroup provides a convenient way to perform common operations for all the Threads belonging to a particular Group. We can create a ThreadGroup by using the following constructor.

§  ThreadGroup g = new ThreadGroup(String groupName);

We can attach a thread to a ThreadGroup by using the following constructor Thread class.

§  Thread t = new Thread(ThreadGroup g,String ThreadName);

Example –

public class ThreadGroup1 implements Runnable{

          @Override

          public void run() {

                   System.out.println(Thread.currentThread().getName()+", "+Thread.currentThread().getPriority()+", "+Thread.currentThread().getThreadGroup());

          }

          public static void main(String[] args) {

                   ThreadGroup1 group = new ThreadGroup1();

                   ThreadGroup tg = new ThreadGroup("Groupthread");

                   Thread t1 = new Thread(tg,group,"t1");

                   t1.start();

                   Thread t2 = new Thread(tg,group,"t2");

                   t2.setPriority(10);

                   t2.start();

          }

}

Output –

t1, 5, java.lang.ThreadGroup[name=Groupthread,maxpri=10]

t2, 10, java.lang.ThreadGroup[name=Groupthread,maxpri=10]

Example –

public class ThreadGroup1 extends Thread{      

          @Override

          public String toString() {

                   return "ThreadGroup1["+getName()+", "+getPriority()+", "+getThreadGroup()+"]";

          }

          public static void main(String[] args) {

                   Thread t1 = new Thread();

                   System.out.println(t1);

                   Thread t2 = new Thread("CMP");

                   System.out.println(t2);

                   Thread t3 = Thread.currentThread();

                   System.out.println(t3);

                   t3.setPriority(9);

                   System.out.println(t3);

                   Thread t4 = new Thread();

                   System.out.println(t4);

          }

}

Output –

Thread[Thread-0,5,main]

Thread[CMP,5,main]

Thread[main,5,main]

Thread[main,9,main]

Thread[Thread-1,9,main]