java同步代码块和同步函数

ゝ一世哀愁。 2022-08-13 11:46 338阅读 0赞

package thread.sync;
/*
 * 需求:储户，两个，每个都到银行存钱每次存100，，共存三次。
 */
public class BankDemo {
    public static void main(String[] args) {
        Cus c = new Cus();
        System.out.println(c);
        //静态同步函数用此,该函数的字节码文件对象
        System.out.println(c.getClass());
        Thread t1 = new Thread(c);
        Thread t2 = new Thread(c);
        t1.start();
        t2.start();
    }
}
class Bank {
    private int sum;
    Object obj = new Object();
    //同步函数,它的锁是this
    public synchronized void add(int num){
        //同步代码块解决线程安全隐患
//        synchronized (obj){
            sum+=num;
            try {
                Thread.sleep(10);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("sum="+sum+"--");
//        }
    }
}
class Cus implements Runnable{
    private Bank b = new Bank();
    @Override
    public void run() {
        for(int i = 0; i<3; i++){
            b.add(100);
        }
    }
}