Start a thread again

Question

I have an event on the start button, every time I press 3 threads are generated that start the count from 30 to 0, to which reach 1º to 0 wins. But however I press the start button a few times and the count starts at 30 and does everything the same, if I keep pressing the start button one or two more times it will errors and stops running the thread. My question is: I start three threads when I press the start button but to do it again in the same frame you have to kill the threads or interrupt them?

C1,C2,C3 are Horse objects.

• Corridacavalos class

  iniciar.addActionListener(new ActionListener(){
  
      @Override
      public void actionPerformed(ActionEvent e) {
          c1.setMovimentos(30);
          c2.setMovimentos(30);
          c3.setMovimentos(30);
  
          c1.start();         //start iniciar o run da thread cavalo c1 - classe cavalo
          c2.start();
          c3.start();
      }
  
  
  });
  

• Horse class extends thread - where I define instructions for it

  @Override
  public void run(){
  try {
      while(movimentos > 0){
          sleep((long) (500*Math.random()));
          movimentos--;
          textField.setText(Integer.toString(movimentos));        //Converter Inteiro para String
      }
  } catch (InterruptedException e) {
      interrupt();
  }
  } 
  

Answer 1

Yes, you need to finish the threads. More than that, you should declare your Horse instances within actionPerformed(), so that each click creates and runs new threads:

iniciar.addActionListener(new ActionListener(){

    @Override
    public void actionPerformed(ActionEvent e) {
        if (c1 != null) {
            c1.setMovimentos(0);
            c1.interrupt();
            c2.setMovimentos(0);
            c2.interrupt();
            c3.setMovimentos(0);
            c3.interrupt();
        }
        c1 = new Cavalo();
        c2 = new Cavalo();
        c3 = new Cavalo();

        c1.setMovimentos(30);
        c2.setMovimentos(30);
        c3.setMovimentos(30);

        c1.start();         //start iniciar o run da thread cavalo c1 - classe cavalo
        c2.start();
        c3.start();
    }


});

Note: the command interrupt() below the catch is unnecessary.