多线程的创建

1. 方式一：

继承Thread类

public class Task1 extends Thread{
    @Override
    public void run() {
        PrimeNumber primeNumber = new PrimeNumber();
        for (int i = 2; i <= 100; i++) {
            if (primeNumber.isPrime(i)){
                System.out.println(i);
            }
        }
    }
}

测试：

        Task1 task1 = new Task1();
        task1.start();

2. 方式二：

实现Runnable接口

public class Task2 implements Runnable{
    @Override
    public void run() {
        LeapYear leapYear = new LeapYear();
        for (int i = 1900; i <= 2023; i++) {
            if (leapYear.isLeap(i)){
                System.out.println(i);
            }
        }
    }
}

测试：

        Task2 task2 = new Task2();
        Thread thread = new Thread(task2);
        thread.start();

3. 方式三：

实现Callable接口

public class Task3 implements Callable<Boolean> {
    @Override
    public Boolean call() throws Exception {
        LeapYear leapYear = new LeapYear();
        return leapYear.isLeap(2023);
    }
}

测试：

        Task3 task3 = new Task3();
        FutureTask futureTask = new FutureTask(task3);
        Thread thread = new Thread(futureTask);
        thread.start();
        System.out.println(futureTask.get());

4. 方式四：

线程池：

        ExecutorService executorService = Executors.newFixedThreadPool(8);
        ThreadPoolExecutor service = (ThreadPoolExecutor) executorService;
        service.setMaximumPoolSize(20);
        service.execute(new Task1());
        service.execute(new Task2());
        try {
            Future future = service.submit(new Task3());
            System.out.println(future.get());
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            service.shutdown();
        }