Redis 分布式锁测试

一、前提依赖（除去SpringBoot项目基本依赖外）：

<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId>
</dependency><!-- 配置使用redis启动器 -->
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId>
</dependency><!-- 引入阿里fastjson2依赖 -->
<dependency><groupId>com.alibaba.fastjson2</groupId><artifactId>fastjson2</artifactId><version>2.0.42</version>
</dependency><!--junit 测试-->
<dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.13.2</version>
</dependency>

二、我这里用到的实体类（Orderinfo ）：

import java.io.Serializable;
import java.math.BigDecimal;
import java.util.Date;
public class Orderinfo implements Serializable {private String onum;private Integer eid;private BigDecimal price;private String fromname;private String fromaddress;private String fromtel;private String toname;private String toaddress;private String totel;private String fromcardnum;private Integer state;private Date createtime;private static final long serialVersionUID = 1L;public String getOnum() {return onum;}public void setOnum(String onum) {this.onum = onum == null ? null : onum.trim();}public Integer getEid() {return eid;}public void setEid(Integer eid) {this.eid = eid;}public BigDecimal getPrice() {return price;}public void setPrice(BigDecimal price) {this.price = price;}public String getFromname() {return fromname;}public void setFromname(String fromname) {this.fromname = fromname == null ? null : fromname.trim();}public String getFromaddress() {return fromaddress;}public void setFromaddress(String fromaddress) {this.fromaddress = fromaddress == null ? null : fromaddress.trim();}public String getFromtel() {return fromtel;}public void setFromtel(String fromtel) {this.fromtel = fromtel == null ? null : fromtel.trim();}public String getToname() {return toname;}public void setToname(String toname) {this.toname = toname == null ? null : toname.trim();}public String getToaddress() {return toaddress;}public void setToaddress(String toaddress) {this.toaddress = toaddress == null ? null : toaddress.trim();}public String getTotel() {return totel;}public void setTotel(String totel) {this.totel = totel == null ? null : totel.trim();}public String getFromcardnum() {return fromcardnum;}public void setFromcardnum(String fromcardnum) {this.fromcardnum = fromcardnum == null ? null : fromcardnum.trim();}public Integer getState() {return state;}public void setState(Integer state) {this.state = state;}public Date getCreatetime() {return createtime;}public void setCreatetime(Date createtime) {this.createtime = createtime;}
}

三、场景-抢单

1. 添加RedisLockUtil：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
@Component
public class RedisLockUtil {@Autowiredprivate RedisTemplate<String, String> redisTemplate;/*** 加锁* @param key   键* @param value 当前时间 + 超时时间* @return 是否拿到锁*/public boolean lock(String key, String value) {if (redisTemplate.opsForValue().setIfAbsent(key, value)) {return true;}String currentValue = redisTemplate.opsForValue().get(key);//如果锁过期if (!StringUtils.isEmpty(currentValue)&& Long.parseLong(currentValue) < System.currentTimeMillis()) {
//设置新值，返回旧值String oldValue = redisTemplate.opsForValue().getAndSet(key, value);//是否已被别人抢占 比对currentValue 和oldValue 是否一致 确保未被其他人抢占return !StringUtils.isEmpty(oldValue) && oldValue.equals(currentValue);}return false;}/*** 解锁** @param key   键* @param value 当前时间 + 超时时间*/public void unlock(String key, String value) {try {String currentValue = redisTemplate.opsForValue().get(key);if (!StringUtils.isEmpty(currentValue) && currentValue.equals(value)) {redisTemplate.opsForValue().getOperations().delete(key);}} catch (Exception e) {System.out.println("redis解锁异常");}}
}

2. 新建RedisLockTest类：

import com.alibaba.fastjson2.JSON;
import com.logistics.order.entity.Orderinfo;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.web.bind.annotation.GetMapping;
import java.util.ArrayList;
import java.util.List;
@SpringBootTest
@RunWith(SpringJUnit4ClassRunner.class)
@Controller
public class RedisLockTest {@Autowiredpublic StringRedisTemplate stringRedisTemplate;@Autowiredpublic RedisLockUtil redisLock;//模拟入库@Testpublic void insertRedis(){Orderinfo orderInfo1 = new Orderinfo();orderInfo1.setOnum("1");orderInfo1.setEid(1);Orderinfo orderInfo2 = new Orderinfo();orderInfo2.setOnum("2");orderInfo2.setEid(2);Orderinfo orderInfo3 = new Orderinfo();orderInfo3.setOnum("3");orderInfo3.setEid(3);List<Orderinfo> orderinfoList = new ArrayList<Orderinfo>();orderinfoList.add(orderInfo1);orderinfoList.add(orderInfo2);orderinfoList.add(orderInfo3);orderinfoList.forEach(x -> {stringRedisTemplate.boundHashOps("order").put(x.getOnum(), JSON.toJSONString(x));});System.out.println("入库成功。");}//压测@GetMapping("/getOrder")public void getOrder(String onum){//定义redis锁的keyString lockkey = "orderkey";//定义锁的超时时间 1sLong ex = 1000L;String valueTimeout = System.currentTimeMillis()+ex+"";//判断锁是否加成功boolean lock = redisLock.lock(lockkey, valueTimeout);if(lock){String orderJson = (String)stringRedisTemplate.boundHashOps("order").get(onum);Orderinfo order = JSON.parseObject(orderJson, Orderinfo.class);System.out.println("订单："+order.getOnum() +" 被抢到。");stringRedisTemplate.boundHashOps("order").delete(onum);//释放锁redisLock.unlock(lockkey,valueTimeout);}}
}

3. 进入 Redis 的可视化客户端工具内查看添加信息：

4. 模拟抢单：

@GetMapping("/getOrder")public void getOrder(String onum){//定义redis锁的keyString lockkey = "orderkey";//定义锁的超时时间 1sLong ex = 1000L;String valueTimeout = System.currentTimeMillis()+ex+"";//判断锁是否加成功boolean lock = redisLock.lock(lockkey, valueTimeout);if(lock){String orderJson = (String)stringRedisTemplate.boundHashOps("order").get(onum);Orderinfo order = JSON.parseObject(orderJson, Orderinfo.class);System.out.println("订单："+order.getOnum() +" 被抢到。");stringRedisTemplate.boundHashOps("order").delete(onum);//释放锁redisLock.unlock(lockkey,valueTimeout);}}