JAVA数据同步----去银行取钱

/** * @author 小阿哥 *  * **/public class MyMain {public static void main(String []str){new MyMain().test();}Card card;void test(){ card=new Card(); //第一个人用card取钱。。new Thread(new Runnable() {@Overridepublic void run() {// TODO Auto-generated method stub{card.update();}}}).start();System.out.println("=============="); //第二个人同样用card取钱。。new Thread(new Runnable() {@Overridepublic void run() {// TODO Auto-generated method stubSystem.out.println("222");{card.update();}}}).start();}}class Card {  synchronized void update(){  long startTime=System.currentTimeMillis(); while(true){ if(System.currentTimeMillis()-startTime>=5000) { System.out.println("取钱完毕"); break; } System.out.println("Name:"+Thread.currentThread().getName()); try{ Thread.sleep(50); }catch(Exception ex) {  }}}}

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