Redis集群利用Redisson实现分布式锁方式

Redisson实现集群环境下的分布式锁十分简单：

引入依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.8.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.lk</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>demo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        //Redis起步依赖
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
            <version>2.1.7.RELEASE</version>
        </dependency>
        //Redisson起步依赖
        <dependency>
            <groupId>org.redisson</groupId>
            <artifactId>redisson-spring-boot-starter</artifactId>
            <version>3.11.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.48</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Redisson配置类

package com.lk.demo.redissionconfig;

import org.redisson.Redisson;
import org.redisson.api.RedissonClient;
import org.redisson.config.Config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

/*
* Redisson的配置类，提供RedissonClient实例
* */
@Configuration
public class RedissionConfiguration {

    @Bean
    public RedissonClient getRedissionClient(){
        Config config=new Config();
        //集群模式,集群节点的地址须使用“redis://”前缀，否则将会报错。
        //此例集群为3节点，各节点1主1从
        config.useClusterServers().addNodeAddress("redis://192.168.37.134:7001","redis://192.168.37.134:7002",
                "redis://192.168.37.134:7003","redis://192.168.37.134:7004","redis://192.168.37.134:7005","redis://192.168.37.134:7006");
        return Redisson.create(config);
    }
}

分布式锁

package com.lk.demo.redissionconfig;

import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Repository;


import java.util.concurrent.TimeUnit;

/*
* 利用RedissonClient部署及解除分布式锁
* 直接调用lock、unlock方法，此方法只允许1个线程取得锁，其余线程将自旋等待
* */

@Repository
public class HandlerLock{
    @Autowired
    private RedisTemplate<String,String> rt;
    //@Qualifier("redisson") //在org.redisson.spring.starter包中，可以从配置文件读取redis配置，并返回redissonclient对象
    @Qualifier("getRedissionClient")//指定从本地自写的class中取得实例
    @Autowired
    private RedissonClient redissonClient;
    //实验方法，测试分布式锁
    public void doLock(String lockname){
        //从RedissonClient取得Rlock实例
        RLock rlock=redissonClient.getLock(lockname);
        //尝试取锁，有效期为3s，到期后自动释放。如果取得锁继续执行。取锁失败则自旋。
        //亦可使用rlock.tryLock（）方法，此方法也为尝试取锁，并返回boolean结果
        rlock.lock(3,TimeUnit.SECONDS);
        //以下为测试业务代码，
        System.out.println(Thread.currentThread().getName()+"取得锁");
        int store=Integer.valueOf(rt.opsForValue().get("store"));
        if(store>0)
        {
            System.out.printf("售出1,当前库存为%d\n",--store);
            rt.opsForValue().set("store",String.valueOf(store));
        }else
            System.out.println("已售完，下次再来吧");
        //业务完成，释放锁
        rlock.unlock();
        System.out.println("解锁");
    }
}

测试Controller

@Controller
public class Controllerdemo {
    @Autowired
    private HandlerLock handlerLock;
    @RequestMapping("/hello")
    @ResponseBody
    public void demo(){
        handlerLock.doLock("luking");
    }

}

并发测试

启动SpringBoot，使用Jmeter进行并发压力测试，Redis中store字段现有值100。

500线程并发，循环2次

控制台结果输出

redis缓存

总结

以上为个人经验，希望能给大家一个参考，也希望大家多多支持。