Java Thread activeCount()方法

java.lang.Thread.activeCount() 方法返回活动线程的当前线程的线程组中的数量。

1 语法

public static int activeCount()

2 参数

无

3 返回值

此方法返回活动线程的当前线程的线程组中的数量。

4 示例 

package com.yiidian;

/**
 * 一点教程网： http://www.yiidian.com
 */
/**
 * java.lang.Thread.activeCount()方法的例子
 */
import java.lang.*;

public class Demo {

    public static void main(String[] args) {

        Thread t = Thread.currentThread();
        t.setName("Admin Thread");

        // set thread priority to 1
        t.setPriority(1);

        // prints the current thread
        System.out.println("Thread = " + t);

        int count = Thread.activeCount();
        System.out.println("currently active threads = " + count);

        Thread th[] = new Thread[count];
        // returns the number of threads put into the array
        Thread.enumerate(th);

        // prints active threads
        for (int i = 0; i < count; i++) {
            System.out.println(i + ": " + th[i]);
        }
    }
}

输出结果为：

Thread = Thread[Admin Thread,1,main]
currently active threads = 2
0: Thread[Admin Thread,1,main]
1: Thread[Monitor Ctrl-Break,5,main]