java 启动线程四种方式

1、继承Thread类

class MyThread extends Thread {
    @Override
    public void run() {
        System.out.println(1111);
    }
}

public static void main(String args[]) {
　　new MyThread().start();
}

2、实现Runnable接口

class MyThread implements Runnable {
    @Override
    public void run() {
        System.out.println(2222);
    }
}

public static void main(String args[]) {
    new Thread(new MyThread()).start();
}

3、直接new Runnable

    public static void main(String args[]) {
        Thread t = new Thread(new Runnable() {
            public void run() {
                System.out.println(3333);
            }
        });
        t.start();
    }

4、jdk自带的线程池

    public static void main(String args[]) {
        ExecutorService pool = Executors.newFixedThreadPool(3);
        pool.execute(new Runnable() {
            @Override
            public void run() {
                System.out.println(4444);
            }
        });
    }