关于守护线程的问题(来源于scjp)
为什么下面这段程序没有输出呢(把setDaemon注释掉或把sleep时间缩短则可以输出),哪位朋友帮忙解答一下,谢谢!
public class A extends Thread {
A() {
setDaemon(true);
}
public void run() {
(new B()).start();
try {
Thread.sleep(600);
} catch (InterruptedException x) {
x.printStackTrace();
}
System.out.println("A done");
}
public static void main(String[] args) {
(new A()).start();
}
}
class B extends Thread {
public void run() {
try {
Thread.sleep(600);
} catch (InterruptedException x) {
x.printStackTrace();
}
System.out.println("B done");
}
}