java的threadpoolexecutor使用例子

ThreadpoolExecutor是Java中的一个线程池管理工具，它可以让我们更好地控制线程的数量和执行情况，以下是一个简单的ThreadpoolExecutor使用例子：

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ThreadPoolExample {

    public static void main(String[] args) {
        ExecutorService executor = Executors.newFixedThreadPool(5);

        for (int i = 0; i < 10; i++) {
            Runnable worker = new WorkerThread("" + i);
            executor.execute(worker);
        }

        executor.shutdown();
        while (!executor.isTerminated()) {
        }

        System.out.println("Finished all threads");
    }
}

class WorkerThread implements Runnable {

    private String message;

    public WorkerThread(String s) {
        this.message = s;
    }

    public void run() {
        System.out.println(Thread.currentThread().getName() + " (Start) message = " + message);
        processCommand();
        System.out.println(Thread.currentThread().getName() + " (End)");
    }

    private void processCommand() {
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    public String toString() {
        return this.message;
    }
}

这个例子定义了一个ExecutorService对象executor，它是由Static方法Executors.newFixedThreadPool(5)初始化而来，5代表着线程池中线程的数量固定为5。创建了一个WorkerThread对象，将其添加到executor中，然后调用executor.shutdown()方法，用于关闭线程池，所有任务都已完成执行。