创建线程的三种方式-（继承Threads，实现Runnable接口，实现Callable接口）

超、凢脫俗 2022-05-21 05:53 446阅读 0赞

# 综述 #

Java使用Thread类代表线程，所有的线程对象都必须是Thread类或其子类的实例。Java可以用三种方式来创建线程，如下所示：

1）继承Thread类创建线程

2）实现Runnable接口创建线程

3）使用Callable和Future创建线程

下面让我们分别来看看这三种创建线程的方法。

# demo实例演示 #

package com.dlut.jeremy;
    
    import java.util.concurrent.Callable;
    import java.util.concurrent.ExecutionException;
    import java.util.concurrent.ExecutorService;
    import java.util.concurrent.Executors;
    import java.util.concurrent.Future;
    
    public class Main {
        
        public static void main(String[] args) {
            // 这是通过继承Thread类创建的线程
            MyThread1 mt1 = new MyThread1();
            mt1.start();
            // 这是实现Runnable接口，比上述步骤多一步
            MyThread2 mt2 = new MyThread2();
            Thread t2 = new Thread(mt2);
            t2.start();
            // 这是实现callable接口
            ExecutorService threadPool = Executors.newSingleThreadExecutor();
            // 启动线程，并且带返回值的
            Future <String> future = threadPool.submit(new CallableTest());
    
            try {
                System.out.println("waiting thread to finish");
                System.out.println(future.get());
            } catch (InterruptedException | ExecutionException e) {
                e.printStackTrace();
            }
        }
    }
    class MyThread1 extends Thread {
        
    
        @Override
        public void run() {
            System.out.println("Thread Body, extends Thread class");
        }
    
    }
    class MyThread2 implements Runnable{
        
    
        @Override
        public void run() {
            System.out.println("Thread Body, implement Runnable interface");
        }
    
    }
    
    class CallableTest implements Callable <String>{
        
        public String call() throws Exception{
            return "Hello World";
        }
    }

程序运行结果：

Thread Body, extends Thread class
    Thread Body, implement Runnable interface
    waiting thread to finish
    Hello World