线程状态观测

Thread. State

public static enum Thread.State
extends Enum<Thread.State>
A thread state. A thread can be in one of the following states:
NEW
A thread that has not yet started is in this state.
RUNNABLE
A thread executing in the Java virtual machine is in this state.
BLOCKED
A thread that is blocked waiting for a monitor lock is in this state.
WAITING
A thread that is waiting indefinitely for another thread to perform a particular action is in this state.
TIMED_WAITING
A thread that is waiting for another thread to perform an action for up to a specified waiting time is in this state.
TERMINATED
A thread that has exited is in this state.
A thread can be in only one state at a given point in time. These states are virtual machine states which do not reflect any operating system thread states.

线程状态。线程可以处于以下状态之一:

• NEW 尚未启动的线程处于此状态
• RUNNABLE 在Java虚拟机中执行的线程处于此状态。
• BLOCKED 被阻塞等待监视器锁定的线程处于此状态
• WAITING 正在等待另一个线程执行特定动作的线程处于此状态
• TIMED WAITING 正在等待另一个线程执行动作达到指定等待时间的线程处于此状态。
• TERMINATED 已退出的线程处于此状态。

一个线程可以在给定时间点处于一个状态。这些状态是不反映任何操作系统线程状态的虚拟机状态。

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();
                }
            }
            System.out.println("//////////////");
        });

        // 观察状态
        Thread.State state = thread.getState();
        System.out.println(state);

        // 启动后状态
        thread.start();
        state = thread.getState();
        System.out.println(state);

        //只要线程不终止,就一直输出状态
        while (state != Thread.State.TERMINATED){
            Thread.sleep(100);
            // 更新线程状态
            state = thread.getState();
            System.out.println(state);
        }

    }
}