How to run the Thread twice

Question

Why the program only can print from 0 to 9 once, not twice?
Thank you!
Here is my program
class TestThread extends Thread
     String name;
     public void run(){
          for(int i=0;i<10;i++){
          System.out.println(i);
          try{
          sleep((long)(Math.random()*1000));
          }catch(Exception e){
               System.out.println(e.toString());
     public static void main(String[] args){
          TestThread t = new TestThread();
          TestThread t1 = new TestThread();
          t.start();
          try{
          t.join();
          }catch(Exception e){
          t.start();

Answer 1

Why the program only can print from 0 to 9 once, not
twice?
Thank you!
Here is my programBecause the run() method returns after printing the numbers once and sleeping a random amount of time. When you return from the run() method, the thread ends.
Threads cannot be restarted, i.e., if a thread has ended you cannot call start() on it again. If you want to do that, just create a new object and call start() on it.
Maybe you want a loop in your run() method:
public void run() {
  while (true) {   // Keep doing this forever!
    for(int i=0;i<10;i++) {
      System.out.println(i);
      try {
        sleep((long)(Math.random()*1000));
      catch(Exception e) {
        System.out.println(e.toString());
}Jesper