测试代码：
public class MyRunnable implements Runnable{
    private String id;

    public MyRunnable(String id) {
        this.id = id;
    }

    @Override
    public void run() {
//        System.out.println(Thread.currentThread().getName() + " Start Time = " + new Date());
        processCommand();
//        System.out.println(Thread.currentThread().getName() + " End Time = " + new Date());
    }

    private void processCommand() {
        try {
            System.out.println("ID: " + this.id + " are in process");
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    @Override
    public String toString() {
        return this.id;
    }
}


public class ThreadPoolExecutorDemo {
    public static final int CORE_POOL_SIZE = 7;
    public static final int MAX_POOL_SIZE = 10;
    public static final int QUEUE_CAPACITY = 20;
    public static final long KEEP_ALIVE_TIME = 1L;


    public static void main(String[] args) {

        ThreadPoolExecutor executor = new ThreadPoolExecutor(
                CORE_POOL_SIZE,
                MAX_POOL_SIZE,
                KEEP_ALIVE_TIME,
                TimeUnit.SECONDS,
                new ArrayBlockingQueue<>(QUEUE_CAPACITY),
                new ThreadPoolExecutor.AbortPolicy());

        for (int i = 0; i < 40; i++) {
            Runnable worker = new MyRunnable("" + i);
            try {
                executor.execute(worker);
            } catch (Exception e) {
                System.out.println("Execute ID:" + i + " got exception with details: " + e.getMessage());
            }

        }

        executor.shutdown();
        while (!executor.isTerminated()) {
        }
        System.out.println("Finished all threads");
    }
}