Java ThreadGroup isDestroyed()方法

ThreadGroup类的isDestroyed()方法测试线程组是否已被销毁。

语法

public boolean isDestroyed()

返回
如果对象被销毁，则此方法返回true。

示例

class NewThread extends Thread   
{  
    NewThread(String threadname, ThreadGroup tg)  
    {  
        super(tg, threadname);  
    }  
    public void run()  
    {  
        for(int i = 0;i < 10;i++)   
        {  
            i++;  
        }  
        System.out.println(Thread.currentThread().getName() + " completed executing");  
    }  
}  
public class ThreadGroupIsDestroyedExp   
{  
    public static void main(String arg[]) throws InterruptedException,  
        SecurityException, Exception  
    {  
        // creating a parent threadGroup  
        ThreadGroup tg1 = new ThreadGroup("Parent thread");  
        // creating a child threadGroup   
        ThreadGroup tg2 = new ThreadGroup(tg1, "Child thread");  

        // creating a thread   
        NewThread t1 = new NewThread("Thread-1", tg1);  
        System.out.println("Starting of Thread-1");  
        t1.start();  

       // creating another thread   
        NewThread t2 = new NewThread("Thread-2", tg2);  
        System.out.println("Starting of Thread-2");  
        t2.start();  

        if (tg1.isDestroyed() == true)  
            System.out.println("Group is destroyed");  
        else  
            System.out.println("Group is not destroyed");  
    }  
}

执行上面示例代码，得到以下结果：

Starting of Thread-1
Starting of Thread-2
Group is not destroyed
Thread-1 completed executing
Thread-2 completed executing