多线程同步案例

全栈程序员-站长 • 2026年3月19日下午5:11 • 未分类 • 阅读 2

利用Thread或Runnable实现一个多用户的银行取款程序。为了保证多个用户在对同一账户取钱时数据的一致性，可通过定义静态变量和线程同步两种方式实现。要求：

静态变量方法

import java.util.Random; class DrawMoney implements Runnable{ 
     private static int deposit = 1000; @Override public void run() { 
     // 设置进行十轮取款 for (int i = 0;i < 10;i++){ 
     try { 
     Thread.sleep(500); } catch (InterruptedException e) { 
     e.printStackTrace(); } if (deposit > 100){ 
     // 随机取款1~100元 int withDrawal = new Random().nextInt(100); // 设置存款数为原存款数减去取款数 synchronized (this) { 
     deposit = deposit - withDrawal; System.out.println("在" + Thread.currentThread().getName() + "取款" + withDrawal + "元，余额为" + deposit + "元。"); } }else { 
     System.out.println("准备在" + Thread.currentThread().getName() + "取款，但是余额不足100元，取款失败。"); } } } } / * @author Laccoliths * @date 2021/11/28 */ public class ThreadStatic { 
     public static void main(String[] args) throws InterruptedException { 
     DrawMoney Money = new DrawMoney(); Thread a = new Thread(Money,"柜台"); Thread b = new Thread(Money,"ATM"); a.start(); b.start(); } }

运行结果
请添加图片描述

线程同步方法

package MoocPart11_01_01; import java.util.Random; / * 共享属性 */ class resource{ 
      private int deposit; / * 构造方法，初始化存款这个属性 * @param deposit */ public resource(int deposit){ 
      super(); this.deposit = deposit; } / * 构造方法，将存款缺省为1000元 */ public resource(){ 
      // 缺省存款为1000元 deposit = 1000; } / * 设置存款数 * @param deposit */ public void setDeposit(int deposit) { 
      this.deposit = deposit; } / * 获取存款数 * @return deposit */ public int getDeposit() { 
      return deposit; } } / * 取钱类 */ class GetMoney implements Runnable{ 
      private final resource resource; / * 构造方法，传入resource对象 */ public GetMoney(resource resource) { 
      this.resource = resource; } @Override public void run() { 
      // 设置进行十轮取款 for (int i = 0;i < 10;i++){ 
      try { 
      Thread.sleep(500); } catch (InterruptedException e) { 
      e.printStackTrace(); } if (resource.getDeposit() > 100){ 
      // 随机取款1~100元 int withDrawal = new Random().nextInt(100); // 设置存款数为原存款数减去取款数 synchronized (this) { 
      resource.setDeposit(resource.getDeposit() - withDrawal); System.out.println("在" + Thread.currentThread().getName() + "取款" + withDrawal + "元，余额为" + resource.getDeposit() + "元。"); } }else { 
      System.out.println("准备在" + Thread.currentThread().getName() + "取款，但是余额不足100元，取款失败。"); } } } } / * @author Laccoliths * @date 2021/11/27 */ public class ThreadSyn { 
      public static void main(String[] args) throws InterruptedException { 
      resource resource = new resource(); GetMoney getMoney = new GetMoney(resource); Thread a = new Thread(getMoney,"柜台"); Thread b = new Thread(getMoney,"ATM"); a.start(); b.start(); } }