如何创建一个ThreadPoolExecutor,根据需要创建线程并在适用时将

>为线程池设置最小大小“N”,这意味着在Executor启动后“N”个线程始终可用.
>为线程池设置最大大小“M”.
>当所有“M”线程都忙时,传入的任务应该排队.
>基于空闲状态超时使(M-N)个线程到期.

我相信HttpClient后面的池管理器可以进行类似的设置.我正在尝试使用ThreadPoolExecutor实现它但无法找到方法.可能吗？

这是一个测试的例子.

public class ExecutorExample {

    public static void main(String[] args) throws InterruptedException {
        int minPoolSize = 2;
        int maxPoolSize = 10;
        int ttlMillis = 100;
        ThreadPoolExecutor startupExecutor = new ThreadPoolExecutor(minPoolSize,maxPoolSize,// surprisingly this is not obeyed.
                ttlMillis,TimeUnit.MILLISECONDS,new LinkedBlockingQueue<Runnable>());

        for (int i = 0; i < 20; i++) {
            System.out.println(Thread.currentThread().getName() + ":" + startupExecutor.getCorePoolSize());
            startupExecutor.execute(new MyRunnable(i));
        }

        for (int i = 0; i < 20; i++) {
            Thread.sleep(1000);
            System.out.println(Thread.currentThread().getName() + ":" + startupExecutor.getCorePoolSize());
        }
    }

}

class MyRunnable implements Runnable {

    int n;

    public MyRunnable(int n) {
        this.n = n;
    }

    @Override
    public void run() {
        try {
            Thread.sleep(2000);
            System.out.println(Thread.currentThread().getName() + ":" + n);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

    }

}