Java中的ThreadGroup

Question

我目前正在学习Java中的Threads基础知识,我正在尝试编写一个简单的Thread Group程序.虽然我得到了不同类型的输出,但我和教程网站一样写了它.下面是我的代码,我得到不同的输出.

public class ThreadGroupDemo implements Runnable {

    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName());
        // get the name of the current thread.
    }

    public static void main(String[] args) {
        ThreadGroupDemo runnable = new ThreadGroupDemo();
        ThreadGroup tg1 = new ThreadGroup("Parent Group");
        // Creating thread Group.

        Thread t1 = new Thread(tg1, new ThreadGroupDemo(), "one");
        t1.start();
        t1.setPriority(Thread.MAX_PRIORITY);

        Thread t2 = new Thread(tg1, new ThreadGroupDemo(), "second");
        t2.start();
        t2.setPriority(Thread.NORM_PRIORITY);

        Thread t3 = new Thread(tg1, new ThreadGroupDemo(), "Three");
        t3.start();

        System.out.println("Thread Group name : " + tg1.getName());
        tg1.list();
    }

}

我得到 输出:

Thread Group name : Parent Group
Three
java.lang.ThreadGroup[name=Parent Group,maxpri=10]
    second
one
Thread[one,10,Parent Group]
    Thread[second,5,Parent Group]
    Thread[Three,5,Parent Group]

---

输出应该是:

one
two
three
Thread Group Name: Parent ThreadGroup
java.lang.ThreadGroup[name=Parent ThreadGroup,maxpri=10]
    Thread[one,5,Parent ThreadGroup]
    Thread[two,5,Parent ThreadGroup]
    Thread[three,5,Parent ThreadGroup] 

我无法理解为什么会这样？设置优先级可以帮助吗？

Answer 1

即使具有优先级，您也无法预测线程的执行顺序。您无法控制日程安排。由您的操作系统决定。

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