1.继承Thread类

　　继承Thread类并重写run()方法

　　调用当前类对象的start()方法会自动启动线程并线程调用run方法。

public  class  Thread3 extends Thread{
   
    @Override
    public void run() {   
        super.run();
    }
}

public void test3() throws InterruptedException {
        Thread t3 = new Thread3();
        t3.start();
    }

2.实现runnable接口

　　与继承Thread类相似，实现run()方法。

public class Thread2 implements Runnable {

    public Thread2(){
        System.out.println("thread2 is creating......");
    }

    public void run() {
        System.out.println("hahaha");
    }
}

Thread t1 = new Thread(new Thread2(),"thread1");//参数1：开启的对象   参数2：线程的name

3.实现callable接口，带返回值类型为Callable<Object>

 　　实现Callable接口的call()方法

　　将这个Callable接口实现类的对象作为参数传递到FutureTask类的构造器中，创建FutureTask类的对象。

　　将这个FutureTask类的对象作为参数传递到Thread类的构造器中，创建Thread类的对象，并调用这个对象的start()方法。

public class Thread5 implements Callable<String> {

    public Object call() throws Exception {
        System.out.println("hahahaha");
        return "实现Callable接口的线程....";
    }
}

public void test4() throws InterruptedException {
        Thread5 thread5 = new Thread5();
        FutureTask futureTask = new FutureTask(thread5);
        Thread thread = new Thread(futureTask,"thread");
        thread.start();
    }