java.lang.ThreadGroup.enumerate(Thread[] list, boolean recurse)%uA0方法复制到指定的数组该线程组中的所有活动线程。如果递归标志为true,也包括引用在此线程的子组的所有活动线程。
如果数组太小而无法保持所有线程,多出来的线程忽略。
声明
以下是java.lang.ThreadGroup.enumerate()方法的声明
public int enumerate(Thread[] list, boolean recurse)
参数
-
list%uA0-- 这是一个数组,用于放置线程列表。
-
recurse%uA0-- 这是一个标志,指示是否也包括在线程组是该线程组的子组线程。
返回值
此方法返回放入数组中的线程的数目。
异常
-
SecurityException%uA0-- 如果当前线程没有权限来枚举此线程组。
例子
下面的例子显示java.lang.ThreadGroup.enumerate()方法的使用。
package com.yiibai import java.lang.* public class ThreadGroupDemo implements Runnable { public static void main(String[] args) { ThreadGroupDemo tg = new ThreadGroupDemo() tg.func() } public void func() { try { // create a parent ThreadGroup ThreadGroup pGroup = new ThreadGroup("Parent ThreadGroup") // create a child ThreadGroup for parent ThreadGroup ThreadGroup cGroup = new ThreadGroup(pGroup, "Child ThreadGroup") // create a thread Thread t1 = new Thread(pGroup, this) System.out.println("Starting " + t1.getName() + "...") t1.start() // create another thread Thread t2 = new Thread(cGroup, this) System.out.println("Starting " + t2.getName() + "...") t2.start() // returns the number of threads put into the array with flag as true Thread[] list = new Thread[pGroup.activeCount()] int count = pGroup.enumerate(list, true) for (int i = 0 i < count i++) { System.out.println("Thread " + list[i].getName() + " found") } // block until the other threads finish t1.join() t2.join() } catch (InterruptedException ex) { System.out.println(ex.toString()) } } // implements run() public void run() { for(int i = 0 i < 1000 i++) { i++ } System.out.println(Thread.currentThread().getName() + " finished executing.") } }
让我们来编译和运行上面的程序,这将产生以下结果:
Starting Thread-0... Starting Thread-1... Thread Thread-0 found Thread Thread-1 found Thread-0 finished executing. Thread-1 finished executing.