Thread

[Abhi vijay]

Source : Devaka Cooray's Exam Simulator

class Trd implements Runnable{
     public void run(){
          try{
               Thread.sleep(1000);
               System.out.print("Ready to Print, ");
               doMore();
          }catch(Exception e){
               System.out.print("Exception Caught, ");
          }
     }
     public synchronized void doMore()throws InterruptedException{
          wait();
          System.out.print("Printed, ");
     }
     public static void main(String args[])throws Exception{
          Thread t=new Thread(new Trd());
          t.start();
          Thread.sleep(5000);
          synchronized(t){
               System.out.print("Now Printing, ");
               t.notifyAll();
          }
     }
}    

Here System.out.print("Printed, ");
this line is not executed???

[Ruben Soto]

Hi Abhi,

I performed some modifications to the code that should allow you to see what's going on. Try to run this:

class Trd implements Runnable{
        public void run(){
                        try{
                                Thread.sleep(1000);
                                System.out.print("Ready to Print, ");
                                doMore();
                        }catch(Exception e){
                                System.out.print("Exception Caught, ");
                        }
        }
        public synchronized void doMore()throws InterruptedException{
                                wait();
                                System.out.print("Printed, ");
        }
        public static void main(String args[])throws Exception{
                        Trd tr = new Trd(); // New
                        Thread t = new Thread(tr); // New
                        //Thread t=new Thread(new Trd());
                        t.start();
                        Thread.sleep(5000);
                        //synchronized(t){
                        synchronized(tr){ // New
                                System.out.print("Now Printing, ");
                                //t.notifyAll();
                                tr.notifyAll(); // New
                        }
        }
}

[Abhi vijay]

Thanks.Ruben. I understood. I am really nervous, as I am making a lot of mistakes in the Thread questions.

[Ruben Soto]

Threads questions are tough for everyone. If you now understand why the code wasn't working as you expected, that means you understand threads quite well though.