线程池拒绝策略

 /**
     * 参数详情
     * 1 核心线程数量
     * 2、最大线程数量
     * 3、线程在多少时间没有操作就释放掉
     * 4、时间单位
     * 5、堵塞策略
     * 6、线程工厂
     * 7、拒绝策略
     */

    /**
     * 超过就会报错的
     */
    @Test
    public void test1() {
        ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(
                2, 5, 3, TimeUnit.SECONDS,
                new LinkedBlockingDeque<>(3),
                Executors.defaultThreadFactory(),
                new ThreadPoolExecutor.AbortPolicy()
        );
        try {
            for (int i = 0; i < 100; i++) {
                threadPoolExecutor.execute(()->{
                    System.out.println(Thread.currentThread().getName()+"----");
                });
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            threadPoolExecutor.shutdown();
        }
    }

    /**
     * 超过最大线程数量就直接使用main线程执行
     */
    @Test
    public void test2() {
        ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(
                2, 5, 3, TimeUnit.SECONDS,
                new LinkedBlockingDeque<>(3),
                Executors.defaultThreadFactory(),
                new ThreadPoolExecutor.CallerRunsPolicy()
        );
        try {
            for (int i = 0; i < 100; i++) {
                threadPoolExecutor.execute(()->{
                    System.out.println(Thread.currentThread().getName()+"----");
                });
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            threadPoolExecutor.shutdown();
        }
    }

    /**
     * 将最早进入队列的任务删除，之后在尝试添加入队列
     */
    @Test
    public void test3() {
        ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(
                2, 5, 3, TimeUnit.SECONDS,
                new LinkedBlockingDeque<>(3),
                Executors.defaultThreadFactory(),
                new ThreadPoolExecutor.DiscardOldestPolicy()
        );
        try {
            for (int i = 0; i < 100; i++) {
                threadPoolExecutor.execute(()->{
                    System.out.println(Thread.currentThread().getName()+"----");
                });
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            threadPoolExecutor.shutdown();
        }
    }
    /**
     * 队列满了丢掉任务不异常
     */
    @Test
    public void test4() {
        ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(
                2, 5, 3, TimeUnit.SECONDS,
                new LinkedBlockingDeque<>(3),
                Executors.defaultThreadFactory(),
                new ThreadPoolExecutor.DiscardPolicy()
        );
        try {
            for (int i = 0; i < 100; i++) {
                threadPoolExecutor.execute(()->{
                    System.out.println(Thread.currentThread().getName()+"----");
                });
            }
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            threadPoolExecutor.shutdown();
        }
    }