D_ThreadJoin.java

D_ThreadJoin.java

package   Threads_PC_341 ;

public   class   D_ThreadJoin   {

     public   static   Thread  thread1 ;
     public   static   Thread  thread2 ;
    
     public   static   void  function1 ()   throws   InterruptedException   {
        
         //-----------------------Thread 1 is running this function
        
         for   ( int  i = 0 ;  i < 5 ;  i ++ )      {  
             System . out . println ( "Thread " +   Thread . currentThread (). getName () + " is running" );
            
         }  
     }

    
     public   static   void  function2 ()   throws   InterruptedException   {
        
         //-----------------------Thread 2 is running this function
        
        thread1 . join ();             // Wait for thread1 to finish first

         //thread1.join(5000);     // Waiting for 5 seconds for thread1 to finish 
            
         for   ( int  i = 0 ;  i < 5 ;  i ++ )      {  
             System . out . println ( "Thread " +   Thread . currentThread (). getName () + " is running" );
            
         }  
     }
    
     public   static   void  main ( String []  args )   throws   InterruptedException   {
                
        
         /*
        join(): is used to start one thread's execution to end of another thread's execution 
        such that thread B does not start running until thread A ends. 
         
                // 1st use: waits for thread A to die.
                 
                If any executing thread B calls join() on thread A (i.e; A.join()) 
                    Immediately B will enter into waiting state (blocked) until A completes its execution.
                
                
                // 2nd use: waits at most this much milliseconds for thread A to die
                
                join(long millis) method waits at most this much milliseconds for certain thread to die. 
                A timeout of 0 means to wait forever
                Giving a timeout within join(), will make the join() effect to be nullified after the specific timeout.
                
         */
    
        thread1  =   new   Thread (  
                 new   Runnable ()   {
                     public   void  run ()   {
                         try   {
                                function1 ();
                         }   catch   ( InterruptedException  e )   {
                                e . printStackTrace ();
                         }
                     }
                 }
         );
        
        thread1 . setName ( "first child" );  
            
            
        thread2  =   new   Thread (  
                 new   Runnable ()   {
                     public   void  run ()   {
                         try   {
                                function2 ();
                         }   catch   ( InterruptedException  e )   {
                                e . printStackTrace ();
                         }
                     }
                 }
         );

        thread2 . setName ( "second child" );  
        
        
        thread1 . start ();  
        thread2 . start ();  
            
     }
}