简单了解Java多线程实现的四种方式

public class Demo extends Thread{

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

  @Override
  public void run() {
    System.out.println("继承Thread类实现多线程");
  }
}

public class Demo2 implements Runnable{

  public static void main(String[] args) {
    new Thread(new Demo2()).start();
  }

  @Override
  public void run() {
    System.out.println("实现Runnable接口的多线程");
  }
}

public class Demo3 implements Callable {

  public static void main(String[] args) throws ExecutionException, InterruptedException {
    FutureTask task=new FutureTask(new Demo3());
    new Thread(task).start();
    System.out.println(task.get());
  }

  @Override
  public String call() throws Exception {
    return "实现Callable接口的多线程";
  }
}

public class Demo4 {

  public static void main(String[] args) {
    ExecutorService executorService= Executors.newCachedThreadPool();
    executorService.execute(new Runnable() {
      @Override
      public void run() {
        System.out.println("线程池实现多线程");
      }
    });
    
    executorService.shutdown();
  }
}