Java监控线程池

ThreadPoolExecutor提供了一组方法用于监控线程池。

int getActiveCount() 获得线程池中当前活动线程的数量。

long getCompletedTaskCount() 返回线程池完成任务的数量。

int getCorePoolSize() 线程池中核心线程的数量。

int getLargestPoolSize() 返回线程池曾经达到的线程的最大数。

int getMaximumPoolSize() 返回线程池的最大容量。

int getPoolSize() 当前线程池的大小。

BlockingQueue getQueue() 返回阻塞队列。

long getTaskCount() 返回线程池收到的任务总数。

package com.wkcto.threadpool;

import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.Executors;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * 监控线程池
 */
public class Test05 {
    public static void main(String[] args) throws InterruptedException {
        //先定义任务
        Runnable r = new Runnable() {
            @Override
            public void run() {
                System.out.println(Thread.currentThread().getId() + " 编号 的线程开始执行: " + System.currentTimeMillis());
                try {
                    Thread.sleep(10000);    //线程睡眠20秒,模拟任务执行时长
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        };

        //定义线程池
        ThreadPoolExecutor poolExecutor = new ThreadPoolExecutor(2, 5, 0, TimeUnit.SECONDS, new ArrayBlockingQueue<>(5), Executors.defaultThreadFactory(), new ThreadPoolExecutor.DiscardPolicy());

        //向线程池提交30个任务
        for (int i = 0; i < 30; i++) {
            poolExecutor.submit(r);
            System.out.println("当前线程池核心线程数量: " + poolExecutor.getCorePoolSize() + ", 最大线程数:" + poolExecutor.getMaximumPoolSize() + ",当前线程池大小:" + poolExecutor.getPoolSize() + ",活动线程数量:" + poolExecutor.getActiveCount()+ ",收到任务数量:" + poolExecutor.getTaskCount() + ",完成任务数: " + poolExecutor.getCompletedTaskCount() + ",等待任务数:" + poolExecutor.getQueue().size()) ;
            TimeUnit.MILLISECONDS.sleep(500);
        }

        System.out.println("-----------------------------------------------");
        while ( poolExecutor.getActiveCount() >= 0 ){
            System.out.println("当前线程池核心线程数量: " + poolExecutor.getCorePoolSize() + ", 最大线程数:" + poolExecutor.getMaximumPoolSize() + ",当前线程池大小:" + poolExecutor.getPoolSize() + ",活动线程数量:" + poolExecutor.getActiveCount()+ ",收到任务数量:" + poolExecutor.getTaskCount() + ",完成任务数: " + poolExecutor.getCompletedTaskCount() + ",等待任务数:" + poolExecutor.getQueue().size()) ;
            Thread.sleep(1000);
        }
    }

}