Java EE——线程状态

前言

从编写Java代码的角度来说，线程一共有六种状态；但是以操作系统的视角来看，线程状态可以分为物种

六种划分

在这里插入图片描述
调用getState()方法获取当前线程状态

一.NEW

定义：线程(对象)被创建但还没有启动

java">public class NEW {public static void main(String[] args) {Thread thread = new Thread(()->{});//thread创建完毕//NEWSystem.out.println(thread.getState());}
}

二.RUNNABLE

定义：线程创建并启动完毕，拥有执行代码的能力或者正在执行代码

java">public class RUNNABLE {public static void main(String[] args) throws InterruptedException {Thread thread = new Thread(()->{while (true){try {Thread.sleep(500);} catch (InterruptedException e) {throw new RuntimeException(e);}System.out.println("Hello Thread");}});//调用startthread.start();//RUNNABLESystem.out.println(thread.getState());}
}

三.WAITING

定义：线程处于等待状态，等待其他线程执行完毕(join)或者其他线程来唤醒(notify)

java">public class WAITING {public static void main(String[] args) throws InterruptedException {Object locker = new Object();Thread thread = new Thread(()->{synchronized (locker){try {//无时间参数的waitlocker.wait();} catch (InterruptedException e) {throw new RuntimeException(e);}}});thread.start();Thread.sleep(100);//WAITINGSystem.out.println(thread.getState());}
}

四.TIMED_WAITING

定义：线程处于等待状态

```
 等待其他线程执行完毕(join)
```
```
 其他线程来唤醒(notify)
```
```
 等待一定的时间后自动唤醒
```

java">public class TIMED_WAITING {public static void main(String[] args) throws InterruptedException {Object locker = new Object();Thread thread = new Thread(()->{synchronized (locker){try {//有时间参数的waitlocker.wait(10000000);} catch (InterruptedException e) {throw new RuntimeException(e);}}});thread.start();Thread.sleep(100);//System.out.println(thread.getState());}
}

五.BLOCKED

定义：线程竞争锁对象失败进入BLOCKED(锁竞争)状态

java">public class BLOCKED {public static void main(String[] args) throws InterruptedException {Object locker = new Object();Thread thread1 = new Thread(()->{synchronized (locker){try {Thread.sleep(1000000);} catch (InterruptedException e) {throw new RuntimeException(e);}}});thread1.start();//thread1先拿到locker锁对象Thread thread2 = new Thread(()->{while (true) {synchronized (locker) {System.out.println("Hello Thread2");}}});thread2.start();//sleep(1000)的作用是让thread2有足够用的时间执行到synchronizedThread.sleep(100);//获取线程状态//BLOCKEDSystem.out.println(thread2.getState());}
}

六.TERMINATED

定义：线程执行完毕或者因异常退出

java">public class TERMINATED {public static void main(String[] args) throws InterruptedException {Thread thread = new Thread(()->{});thread.start();//等待线程执行完毕thread.join();//TERMINATEDSystem.out.println(thread.getState());}
}