All for Joomla All for Webmasters

The join() method

The join() method waits for a thread to die. In other words, it causes the currently running threads to stop executing until the thread it joins with completes its task.

Syntax:

public void join()throws InterruptedException
public void join(long milliseconds)throws InterruptedException

Example of join() method

  1. class TestJoinMethod1 extends Thread{
  2.  public void run(){
  3.   for(int i=1;i<=5;i++){
  4.    try{
  5.     Thread.sleep(500);
  6.    }catch(Exception e){System.out.println(e);}
  7.   System.out.println(i);
  8.   }
  9.  }
  10. public static void main(String args[]){
  11.  TestJoinMethod1 t1=new TestJoinMethod1();
  12.  TestJoinMethod1 t2=new TestJoinMethod1();
  13.  TestJoinMethod1 t3=new TestJoinMethod1();
  14.  t1.start();
  15.  try{
  16.   t1.join();
  17.  }catch(Exception e){System.out.println(e);}
  18.  t2.start();
  19.  t3.start();
  20.  }
  21. }
Output:1
       2
       3
       4
       5
       1
       1
       2
       2
       3
       3
       4
       4
       5
       5

As you can see in the above example,when t1 completes its task then t2 and t3 starts executing.

Example of join(long miliseconds) method

  1. class TestJoinMethod2 extends Thread{
  2.  public void run(){
  3.   for(int i=1;i<=5;i++){
  4.    try{
  5.     Thread.sleep(500);
  6.    }catch(Exception e){System.out.println(e);}
  7.   System.out.println(i);
  8.   }
  9.  }
  10. public static void main(String args[]){
  11.  TestJoinMethod2 t1=new TestJoinMethod2();
  12.  TestJoinMethod2 t2=new TestJoinMethod2();
  13.  TestJoinMethod2 t3=new TestJoinMethod2();
  14.  t1.start();
  15.  try{
  16.   t1.join(1500);
  17.  }catch(Exception e){System.out.println(e);}
  18.  t2.start();
  19.  t3.start();
  20.  }
  21. }
Output:1
       2
       3
       1
       4
       1
       2
       5
       2
       3
       3
       4
       4
       5
       5

In the above example,when t1 is completes its task for 1500 miliseconds(3 times) then t2 and t3 starts executing.

getName(),setName(String) and getId() method:

public String getName()
public void setName(String name)
public long getId()
  1. class TestJoinMethod3 extends Thread{
  2.   public void run(){
  3.    System.out.println(“running…”);
  4.   }
  5.  public static void main(String args[]){
  6.   TestJoinMethod3 t1=new TestJoinMethod3();
  7.   TestJoinMethod3 t2=new TestJoinMethod3();
  8.   System.out.println(“Name of t1:”+t1.getName());
  9.   System.out.println(“Name of t2:”+t2.getName());
  10.   System.out.println(“id of t1:”+t1.getId());
  11.   t1.start();
  12.   t2.start();
  13.   t1.setName(“Sonoo Jaiswal”);
  14.   System.out.println(“After changing name of t1:”+t1.getName());
  15.  }
  16. }
Output:Name of t1:Thread-0
       Name of t2:Thread-1
       id of t1:8
       running...
       After changling name of t1:Sonoo Jaiswal
       running...
     

The currentThread() method:

The currentThread() method returns a reference to the currently executing thread object.

Syntax:

public static Thread currentThread()

Example of currentThread() method

  1. class TestJoinMethod4 extends Thread{
  2.  public void run(){
  3.   System.out.println(Thread.currentThread().getName());
  4.  }
  5.  }
  6.  public static void main(String args[]){
  7.   TestJoinMethod4 t1=new TestJoinMethod4();
  8.   TestJoinMethod4 t2=new TestJoinMethod4();
  9.   t1.start();
  10.   t2.start();
  11.  }
  12. }
Output:Thread-0
       Thread-1
PinIt
submit to reddit

Leave a Reply

Top