java多进程

class NewThread implements Runnable{
    Thread t;
    NewThread(){
        t = new Thread(this, "Demo Thread");
        System.out.println("child thread"+t);
        t.start();
    }
    public void run(){
        System.out.println("begin child");
        try{
            for(int i=5;i>0;i--){
                System.out.println("child Thread:"+i);
                Thread.sleep(50);
            }
        }catch(InterruptedException e){
            System.out.println("child interrupted");
        }
        System.out.println("end child");
        
    }
}
public class test {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        NewThread ob = new NewThread();
        System.out.println("main is :"+ob.t.isAlive());
        try{
            ob.t.join();
        }catch(InterruptedException e){
            System.out.println("main interrupted");
        }
        System.out.println("main is :"+ob.t.isAlive());
    }

}