线程学习【八】 join方法

多线程学习------join方法

package com.zzl.thread;

/**
 * join
 * 当A线程遇到了B线程的.join()方法的时候，A就会等待。等B线程执行完，A线程才会执行。
 * 
 * join可以用来临时加入线程执行
 */
class JoinRunnable implements Runnable{

	@Override
	public void run() {
		for(int i = 0;i < 10;i++){
			System.out.println(Thread.currentThread().getName()+"......."+i);
		}
	}
	
}


public class JoinDemo {
	
	public static void main(String[] args) {
		JoinRunnable r =new JoinRunnable();
		Thread t1 = new Thread(r);
		Thread t2 = new Thread(r);
		t1.start();
		try {
			t1.join();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		t2.start();
		
	}

}

把 try catch注释掉，运行效果如下(两个线程交替抢占cpu资源)：

Thread-0.......0
Thread-0.......1
Thread-1.......0
Thread-1.......1
Thread-1.......2
Thread-0.......2
Thread-1.......3
Thread-0.......3
Thread-0.......4
Thread-0.......5
Thread-0.......6
Thread-0.......7
Thread-0.......8
Thread-0.......9
Thread-1.......4
Thread-1.......5
Thread-1.......6
Thread-1.......7
Thread-1.......8
Thread-1.......9

如果线程 t1 start后调用了 t1.join(),运行效果如下（t1线程先运行完，然后运行t2线程）：

Thread-0.......0
Thread-0.......1
Thread-0.......2
Thread-0.......3
Thread-0.......4
Thread-0.......5
Thread-0.......6
Thread-0.......7
Thread-0.......8
Thread-0.......9
Thread-1.......0
Thread-1.......1
Thread-1.......2
Thread-1.......3
Thread-1.......4
Thread-1.......5
Thread-1.......6
Thread-1.......7
Thread-1.......8
Thread-1.......9