java 多线程-线程的状态

观察线程的状态
State state=Thread对象.getState();
int num=Thread.activeCount();//当前活跃的线程个数

public class n {

public static void main(String[]args) throws InterruptedException
{
    Thread t =new Thread(()->{
        for(int i=0;i<5;i++)
        {
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        System.out.println("a");
        }
    });
    //观察状态
    State state=t.getState();
    System.out.println(state);//创建的对象处于NEW新生状态

    t.start();
    state=t.getState();
    System.out.println(state);//处于RUNNABLE

    while(state!=Thread.State.TERMINATED)
    {

        System.out.println(num);
        Thread.sleep(200);
        state =t.getState();//TIMED_WAITING
        System.out.println(state);
    }
    **或者:**
    while(true)
    {
        int num=Thread.activeCount();//当前活动的线程数，包括主线程一共有两个
        if(num==1)
        {
            break;
        }
        System.out.println(num);
        Thread.sleep(200);
        state=t.getState();
        System.out.println(state);
    }
    state=t.getState();
    System.out.println(state);//TERMINATED
}

}