线程池用法

男娘i 2022-05-17 04:24 270阅读 0赞

public class ThreadPoolTest {
        public static void main(String[] args) {
            ExecutorService executorService = Executors.newCachedThreadPool();
            for (int i = 1; i <=10 ; i++) {
                final int task = i;
                executorService.execute(new Runnable() {
                    @Override
                    public void run() {
                        for (int j = 1; j <= 10; j++) {
                            try {
                                Thread.sleep(10);
                            } catch (InterruptedException e) {
                                e.printStackTrace();
                            }
                            System.out.println(Thread.currentThread().getName() + "   is for    " + "   j=  " + j +"    task =   " + task);
                        }
                    }
                });
            }
            //executorService.shutdown();
        }
    }
    代码很简单就不解释了

`看一下第二种方式`

public class SemaphoreTest {
        public static void main(String[] args) {
            ExecutorService service = Executors.newCachedThreadPool();
            final Semaphore s = new Semaphore(3);
            for (int i = 0; i < 10; i++) {// 开是个对象
                Runnable runnable = new Runnable() {
                    @Override
                    public void run() {
                        try {
                            s.acquire();// 判断对象的信号灯，亮就代表有线程
                        }catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                        System.out.println("线程" + Thread.currentThread() + "进入，当前已有" + s.availablePermits());
                        try {
                            Thread.sleep((long)(Math.random()*10000));
                        }catch (InterruptedException e){
                            e.printStackTrace();
                        }
                        System.out.println("线程"+Thread.currentThread()+"即将离开");
                        s.release();
                        System.out.println("线程"+Thread.currentThread()+"线程已离开,当前已有"+s.availablePermits());
                    }
                };
                service.execute(runnable);// 把对象装线程池
            }
        }
    }