join()方法如何在多线程中使用

public class TestThread5 {  public static void main(String[] args) throws InterruptedException {    Runner0 run5 = new Runner0();    Thread th6 = new Thread(run5);    th6.start();    th6.join();//join()方法用在此处是为了等待主线程结束后运行子线程     for(int i=0;i<5;i++){      System.out.println("子线程："+i);      }  }}  class Runner0 implements Runnable{    public void run(){      for(int i=0;i<5;i++)        System.out.println("主线程:"+i);    }  }