package cunqianTest;
/*
 * 模擬存錢，取錢
 * 如果輸入的數字為正數，則為存錢反之取錢
 */
public class Card {
private String name;
private int money;


public Card(String name, int money) {
super();
this.name = name;
this.money = money;
}


public Card() {
super();
}


public String getName() {
return name;
}


public void setName(String name) {
this.name = name;
}


public int getMoney() {
return money;
}


public void setMoney(int money) {
this.money = money;
}


@Override
public String toString() {
return "Card [name=" + name + ", money=" + money + "]";
}


public void add(int money) {
if (money > 0) {// 存錢
this.money = this.money + money;
System.out.println(Thread.currentThread().getName() + " 存了" + money + "\t餘額為：" + this.getMoney());


} else {// 取錢
this.money = this.money + money;
System.out.println(Thread.currentThread().getName() + " 取了" + (-money) + "\t餘額為：" + this.getMoney());
}
}

}

package cunqianTest;


public class CardUtil implements Runnable {
private Card card;
public CardUtil(Card card) {
super();
this.card = card;
}
@Override
public void run() {
int count = 0;
int num;
for (int i = 0; i < 20; i++) {
synchronized (card) {
//減500的作用讓隨機數有機會產生負數
num = (int) (Math.random() * 1000 + 1) - 500;
card.add(num);
}
}
}
}

package cunqianTest;


public class TestCard {


public static void main(String[] args) {
Card card = new Card();
CardUtil util = new CardUtil(card);
CardUtil util2 = new CardUtil(card);
Thread t1 = new Thread(util);
Thread t2 = new Thread(util2);
t1.start();
t2.start();
}
}