多线程之join

t.join()方法阻塞调用此方法的线程(calling thread)，直到线程t完成，此线程再继续；通常用于在main()主线程内，等待其它线程完成再结束main()主线程。

package thread;/** * T1执行之后T2  之后T3 * @author zhoushiwen * */public class Thread1 {public static void main(String[] args) throws Exception{Thread t1 = new Thread("t1"){@Overridepublic void run() {System.out.println("t1.....");try {Thread.sleep(1000);} catch (InterruptedException e) {e.printStackTrace();}}};Thread t2 = new Thread("t2"){@Overridepublic void run() {try {t1.join();} catch (InterruptedException e1) {e1.printStackTrace();}System.out.println("t2.....");try {Thread.sleep(1000);} catch (InterruptedException e) {e.printStackTrace();}}};Thread t3 = new Thread("t3"){@Overridepublic void run() {try {t2.join();} catch (InterruptedException e1) {e1.printStackTrace();}System.out.println("t3.....");try {Thread.sleep(1000);} catch (InterruptedException e) {e.printStackTrace();}System.out.println("t3.....over");}};t1.start();t2.start();t3.start();}}