守护线程

对于线程，有个守护的线程的概念。如何理解呢？比如A线程里，new 出了线程B，如果A不是守护线程，那么A结束后，B依然可以执行。如果是守护线程，当A结束后，B不再执行

 

package thread;

 

public class ChildParentThread {

 

public static void main(String args[]){

 

Thread t = new ParentThread("parent");

t.setDaemon(true);

t.start();

}

}

 

class ParentThread extends Thread{

 

public ParentThread(String name){

  super(name);

}

public void run(){

String temp = Thread.currentThread().getName();

System.out.println(temp+" before   ");

new ChildThread("child").start();

 

System.out.println(temp+ " after   ");

 

}

}

 

class ChildThread extends Thread{

 

public ChildThread(String name){

 super(name);

}

public void run(){

String temp = Thread.currentThread().getName();

for(int i =0;i<100;i++){

System.out.println(temp+","+i);

try {

Thread.sleep(1000);

} catch (InterruptedException e) {

e.printStackTrace();

}

}

 

}

}