[Java]_ch14.3_執行緒的同步問題

[Java]_ch14.3_執行緒的同步問題

package YPU;

class Bank{

static int sum=0;

public synchronized static void add(int n){

int tmp=sum;

tmp=tmp+n;

try {

Thread.sleep((int)(Math.random()*100));

} catch (InterruptedException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

sum=tmp;

System.out.println("sum="+sum+"..."+Thread.currentThread().getName());

}

}

class Customer implements Runnable{



@Override

public void run() {

for(int i=0;i<3;i++)

Bank.add(100);

}

}

public class A14_1 {



public static void main(String[] args) {

Customer c1=new Customer();

Customer c2=new Customer();

Thread t1=new Thread(c1,"客戶1:");

Thread t2=new Thread(c2,"客戶2:");

t1.start();

t2.start();

}



}