关于java的synchronized关键字，wait()，notify() 的例子，方便大家快速理解和应用。

做java开发多年，一直都没有机会使用wait()和notify()，今天写个例子出来，加深对对象锁的理解:

package com.synchronize;import java.util.Date;public class People {private String name;public People(String name) {this.name=name;}public void shop() throws InterruptedException {synchronized (this) {System.out.println(name+" start to shop:" + new Date().toLocaleString());Thread.currentThread().sleep(2000);System.out.println(name+" end to shop:" + new Date().toLocaleString());}}public void work() throws InterruptedException {synchronized (this) {System.out.println(name+" start to work:" + new Date().toLocaleString());Thread.currentThread().sleep(2000);System.out.println(name+" end to work:" + new Date().toLocaleString());}}public void think() throws InterruptedException {synchronized (this) {System.out.println(name+" start to think:" + new Date().toLocaleString());this.wait(2000);System.out.println(name+" end to think:" + new Date().toLocaleString());}}public void talk() throws InterruptedException {synchronized (this) {System.out.println(name+" start to talk:" + new Date().toLocaleString());this.notify();Thread.currentThread().sleep(2000);System.out.println(name+" end to talk:" + new Date().toLocaleString());}}public static void main(String[] args) throws InterruptedException {//test synchronized keyword, run shop() first, then run work(). final People John = new People("John");Thread t1 = new Thread() {@Overridepublic void run() {try {John.shop();} catch (InterruptedException e) {e.printStackTrace();}}};Thread t2 = new Thread() {@Overridepublic void run() {try {John.work();} catch (InterruptedException e) {e.printStackTrace();}}};t1.start();Thread.currentThread().sleep(100);t2.start();//test wait() and notify(), first think(), interrupt by talk(), end to talk, last end to think.final People Mike = new People("Mike");Thread t3 = new Thread() {@Overridepublic void run() {try {Mike.think();} catch (InterruptedException e) {e.printStackTrace();}}};Thread t4 = new Thread() {@Overridepublic void run() {try {Mike.talk();} catch (InterruptedException e) {e.printStackTrace();}}};t3.start();Thread.currentThread().sleep(100);t4.start();}}