5.5、观察线程状态

package com.example.demo.thread;

/**
 * @projectName: demo
 * @package: com.example.demo.thread
 * @className: TestState
 * @author:
 * @description: 观察线程状态
 * @date: 2021/12/7 21:35
 */
public class TestState {
    public static void main(String[] args) throws InterruptedException {
        Thread thread = new Thread(() -> {
            for (int i = 0; i < 5; i++) {
                try {
                    Thread.sleep(1000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });

        // 线程状态
        Thread.State state = thread.getState();
        System.out.println(state);

        thread.start();
        state = thread.getState();
        System.out.println(state);

        while (thread.isAlive()){
            state = thread.getState();
            Thread.sleep(1000);
            System.out.println(state);
        }

        state = thread.getState();
        System.out.println(state);

        // 会出现异常：死亡的线程不能再次启动！！！
        thread.start();
    }
}

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