[Java知识库]黑马JAVA P175 线程池处理Runnable、Callable任务

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package com.itheima.d8_threadpool;

public class MyRunnable implements Runnable{
    @Override
    public void run() {
        for (int i = 0; i < 5; i++) {
            System.out.println(Thread.currentThread().getName() + "输出了: HelloWorld ==>" + i);
        }
        try {
            System.out.println(Thread.currentThread().getName() + "本任务与线程绑定了，线程进入了休眠了~~~");
            Thread.sleep(10000000);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

package com.itheima.d8_threadpool;

import java.util.concurrent.*;

/**
 * 目标：自定义一个线程池对象，并测试其特性。
 *
 */
public class ThreadPoolDemo1 {
    public static void main(String[] args) {
        //1.创建线程池对象
//        public  ThreadPoolExecutor (int corePoolSize,
// *                               int maximumPoolSize,
// *                               long keepAliveTime,
// *                               TimeUnit unit,
// *                               BlockingQueue<Runnable> workQueue,
// *                               ThreadFactory threadFactory,
// *                               RejectedExecutionHandler handler)


        ExecutorService pool = new ThreadPoolExecutor(3,5,
                6,TimeUnit.SECONDS,new ArrayBlockingQueue<>(5),Executors.defaultThreadFactory(),
        new ThreadPoolExecutor.AbortPolicy() );

        //2.给任务线程池处理。
        Runnable target = new MyRunnable();
        pool.execute(target);
        pool.execute(target);
        pool.execute(target);

        pool.execute(target);
        pool.execute(target);
        pool.execute(target);
        pool.execute(target);
        pool.execute(target);
        //创建临时线程
        pool.execute(target);
        pool.execute(target);
        //不创建  拒绝策略被触发！！
//        pool.execute(target);

        //关闭线程池（开发中一般不会使用）
//        pool.shutdownNow();//立即关闭，即使任务没有完成，丢失任务的！
        pool.shutdownNow();//会等待全部任务执行完毕之后再关闭（建议使用的）

    }
}

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package com.itheima.d8_threadpool;

import java.util.concurrent.Callable;

/**
 * 1.定义一个任务类 实现Callable 接口  应该申明线程任务执行完毕后的结果的数据类型
 */


public class MyCallable implements Callable<String> {
    private int n ;
    public MyCallable(int n ){this.n = n;}

    /**
     * 2.重写call方法（任务方法）
     * @return
     * @throws Exception
     */

    @Override
    public String call() throws Exception {
        int sum = 0;
        for (int i = 1; i <= n ; i++) {
            sum += i;
        }
        return Thread.currentThread().getName() + "执行 1-" + n + "的和，结果是:" + sum;
    }
}

package com.itheima.d8_threadpool;

import java.util.concurrent.*;

/**
 * 目标：自定义一个线程池对象，并测试其特性。
 *
 */
public class ThreadPoolDemo2 {
    public static void main(String[] args) throws Exception {
        //1.创建线程池对象
//        public  ThreadPoolExecutor (int corePoolSize,
// *                               int maximumPoolSize,
// *                               long keepAliveTime,
// *                               TimeUnit unit,
// *                               BlockingQueue<Runnable> workQueue,
// *                               ThreadFactory threadFactory,
// *                               RejectedExecutionHandler handler)


        ExecutorService pool = new ThreadPoolExecutor(3,5,
                6,TimeUnit.SECONDS,new ArrayBlockingQueue<>(5),Executors.defaultThreadFactory(),
        new ThreadPoolExecutor.AbortPolicy() );

        //2.给任务线程池处理。
       Future<String> f1 = pool.submit(new MyCallable(100));
       Future<String> f2 = pool.submit(new MyCallable(200));
       Future<String> f3 = pool.submit(new MyCallable(300));
       Future<String> f4 = pool.submit(new MyCallable(400));
       Future<String> f5 = pool.submit(new MyCallable(500));

//       String rs = f1.get();
//        System.out.println(rs);

        System.out.println(f1.get());
        System.out.println(f2.get());
        System.out.println(f3.get());
        System.out.println(f4.get());
        System.out.println(f5.get());
    }
}

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