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javamultithreading

Java - creating a new thread


I'm new to threads. I wanted to create some simple function working separately from main thread. But it doesn't seem to work. I'd just like to create new thread and do some stuff there independently of what's happening on main thread. This code may look weird but I don't have much experience with threading so far. Could you explain me what's wrong with this?

  public static void main(String args[]){
      test z=new test();

      z.setBackground(Color.white);

      frame=new JFrame();
      frame.setSize(500,500);
      frame.add(z);
      frame.addKeyListener(z);
      frame.setVisible(true);

      one=new Thread(){
          public void run() {
              one.start();
              try{
                  System.out.println("Does it work?");
                  Thread.sleep(1000);
                  System.out.println("Nope, it doesnt...again.");
              } catch(InterruptedException v){System.out.println(v);}
          }
      };
  }

Solution

  • You are calling the one.start() method in the run method of your Thread. But the run method will only be called when a thread is already started. Do this instead:

    one = new Thread() {
        public void run() {
            try {
                System.out.println("Does it work?");
    
                Thread.sleep(1000);
    
                System.out.println("Nope, it doesnt...again.");
            } catch(InterruptedException v) {
                System.out.println(v);
            }
        }  
    };
    
    one.start();