java.lang.ThreadGroup.enumerate(ThreadGroup[] list, boolean recurse)方法實例
java.lang.ThreadGroup.enumerate(ThreadGroup[] list, boolean recurse) 方法複製到該線程組中指定的數組引用所有活動子組。如果遞歸標誌為true,也包括提及的子組等所有活動子組。
聲明
以下是java.lang.ThreadGroup.enumerate()方法的聲明
public int enumerate(ThreadGroup[] list, boolean recurse)
參數
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list -- 這是一個數組,放置線程組的列表。
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recurse -- 這是一個標誌,指示是否遞歸枚舉所有包含的線程組。
返回值
此方法返回放入數組線程組的數目。
異常
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SecurityException -- 如果當前線程冇有權限來枚舉此線程組。
例子
下麵的例子顯示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 thread groups put into the array with flag as true */ ThreadGroup[] grpList = new ThreadGroup[pGroup.activeGroupCount()]; int count = pGroup.enumerate(grpList, true); for (int i = 0; i < count; i++) { System.out.println("ThreadGroup" + grpList[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."); } }
讓我們來編譯和運行上麵的程序,這將產生以下結果:
Starting Thread-0... Starting Thread-1... ThreadGroup Child ThreadGroup found Thread-0 finished executing. Thread-1 finished executing.