我正在学习多线程的概念,在这里我试图找到数组中活动线程的数量,但是 ThreadGroup.activeCount() 的方法>只会返回零值。
代码如下:
线程对象类:-
class th1 extends Thread
{
public th1(String threadName,ThreadGroup tg1)
{
super(tg1,threadName);
}
@Override
public void run()
{
try {
Thread.sleep(5000);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
System.out.println(Thread.currentThread().getName() + " is running");
}
}
主班:-
public class enumerate_demo
{
public static void main(String[] args)
{
ThreadGroup tg1 = new ThreadGroup("group 1");
Thread t1 = new Thread(new th1("t-1",tg1));
t1.start();
Thread t2 = new Thread(new th1("t-2",tg1));
t2.start();
Thread t3 = new Thread(new th1("t-3",tg1));
t3.start();
System.out.println("Number of active count :- " + tg1.activeCount());
Thread[] group = new Thread[tg1.activeCount()];
int count = tg1.enumerate(group);
for (int i = 0; i < count; i++)
{
System.out.println("Thread " + group[i].getName());
}
}
}