白话理解java多线程之join()方法

join字面意思是加入,我理解为插队.

举例:妈妈在炒菜,发现没哟酱油了,让儿子去打酱油,儿子打完酱油,妈妈炒完菜,全家一起吃

package cn.yh.thread01;
/**
 * 
 * 打酱油的例子
 */
public class Demo03 {
	public static void main(String[] args) {
		Mum mum = new Mum();
		mum.start();
	}
}
class Mum extends Thread{
	@Override
	public void run() {
		System.out.println("老妈洗菜");
		System.out.println("老妈切菜");
		System.out.println("老妈开始炒菜");
		System.out.println("老妈没有酱油了");
		System.out.println("老妈让儿子去打酱油");
		Son son = new Son();
		son.start();
		try {
			son.join();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		System.out.println("老妈炒好了");
		System.out.println("全家人一起吃饭");
	}
}

class Son extends Thread{
	@Override
	public void run() {
		System.out.println("儿子下楼");
		try {
			Thread.sleep(100);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		System.out.println("儿子买完酱油了");
		System.out.println("儿子把酱油交给妈妈");
	}
}

注意:join方法,在start()方法之后执行.