传统创建线程的方式

extends Thread
implements Runnable

package me.qianlv;
public class TraditionalThread {
	public static void main(String[] args) {
		//创建线程的第一种方式
		Thread thread1 = new Thread() {
			@Override
			public void run() {
				while(true){
					try {
						Thread.sleep(500);
					} catch (InterruptedException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
					System.out.println("thread 1:" + Thread.currentThread().getName());
				}
			}
		};
		thread1.start();
		//创建线程的第二种方式
		Thread thread2 = new Thread(new Runnable() {
			@Override
			public void run() {
				while(true){
					try {
						Thread.sleep(500);
					} catch (InterruptedException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
					System.out.println("thread 2:" + Thread.currentThread().getName());
				}
			}
		});
		thread2.start();
		//下面这种写法，究竟会执行哪个run方法呢？
		Thread thread3 = new Thread(new Runnable(){
			@Override
			public void run(){
				while(true){
					try {
						Thread.sleep(500);
					} catch (InterruptedException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
					System.out.println("thread 3: Runnable " + Thread.currentThread().getName());
				}
			}
		}){
			@Override
			public void run(){
				while(true){
					try {
						Thread.sleep(500);
					} catch (InterruptedException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
					System.out.println("thread 3: Thread " + Thread.currentThread().getName());
				}
			}
		};
		thread3.start();
	}
}

输出结果:

1
2
3

thread 1:Thread-0
thread 2:Thread-1
thread 3: Thread Thread-2

对于第三种输出结果,利用Java的多态特性即可知道原因.new Thread(){}创建了 Thread 子类,所以在运行的时候,首先会查看子类是否有 run 方法,当有时,执行此子类的方法.