int enumerate(Thread[] list, boolean recurse)
描述 (Description)
java.lang.ThreadGroup.enumerate(Thread[] list, boolean recurse)方法将此线程组中的每个活动线程复制到指定的数组中。 如果recurse标志为true，则还包括对该线程子组中每个活动线程的引用。
如果数组太短而无法容纳所有线程，则会以静默方式忽略额外的线程。
声明 (Declaration)
以下是java.lang.ThreadGroup.enumerate()方法的声明
public int enumerate(Thread[] list, boolean recurse)
参数 (Parameters)
list - 这是一个放置线程列表的数组。
recurse - 这是一个标志，指示是否还包括作为此线程组的子组的线程组中的线程。
返回值 (Return Value)
此方法返回放入数组中的线程数。
异常 (Exception)
SecurityException - 如果当前线程没有枚举此线程组的权限。
例子 (Example)
以下示例显示了java.lang.ThreadGroup.enumerate（）方法的用法。
package com.iowiki;
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.");
}
}
让我们编译并运行上面的程序，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.
