ThreadGroup类的enumerate()方法用于将每个活动线程的线程组及其子组复制到指定的数组中。 此方法使用tarray参数调用`enumerate()方法。
语法
public int enumerate(Thread[] tarray)
参数
tarray:它是要复制到的Thread对象数组。
返回
此方法返回放入数组的线程数。
package com.yiibai.threadgroup;
class NewThread extends Thread {
NewThread(String threadname, ThreadGroup tg) {
super(tg, threadname);
}
public void run() {
for (int i = 0; i < 10; i++) {
try {
Thread.sleep(10);
} catch (InterruptedException ex) {
System.out.println(Thread.currentThread().getName() + " interrupted");
}
}
System.out.println(Thread.currentThread().getName() + " completed executing");
}
}
public class ThreadGroupEnumerateExp {
public static void main(String arg[]) {
// creating the ThreadGroup
ThreadGroup g1 = new ThreadGroup("Parent thread");
// creating a child ThreadGroup for parent ThreadGroup
ThreadGroup g2 = new ThreadGroup(g1, "child thread");
// creating a thread
NewThread t1 = new NewThread("Thread-1", g1);
System.out.println("Starting of Thread-1");
t1.start();
// creating another thread
NewThread t2 = new NewThread("Thread-2", g1);
System.out.println("Starting of Thread-2");
t2.start();
// returns the number of threads put into the array
Thread[] tarray = new Thread[g1.activeCount()];
int count = g1.enumerate(tarray);
// prints active threads
for (int i = 0; i < count; i++)
System.out.println(tarray[i].getName() + " found");
}
}
执行上面示例代码，得到以下结果:
Starting of Thread-1
Starting of Thread-2
Thread-1 found
Thread-2 found
Thread-1 completed executing
Thread-2 completed executing
