第基于Redis分布式鎖Redisson及SpringBoot集成Redisson目錄-分布式鎖需要具備的條件和剛需-Redisson使用-SpringBoot集成Redisson

-分布式鎖需要具備的條件和剛需

獨(dú)占性：OnlyOne，任何時(shí)刻只能有且僅有一個(gè)線程持有高可用：若redis集群環(huán)境下，不能因?yàn)槟骋粋€(gè)節(jié)點(diǎn)掛了而出現(xiàn)獲取鎖和釋放鎖失敗的情況防死鎖：杜絕死鎖，必須有超時(shí)控制機(jī)制或者撤銷操作，有個(gè)兜底終止跳出方案不亂搶：防止張冠李戴，不能私下unlock別人的鎖，只能自己加鎖自己釋放重入性：同一個(gè)節(jié)點(diǎn)的同一個(gè)線程如果獲得鎖之后，它也可以再次獲取這個(gè)鎖

-Redisson使用

引入redisson依賴：

dependency

groupIdorg.redisson/groupId

artifactIdredisson/artifactId

version3.16.2/version

/dependency

添加redisson配置：

importorg.redisson.Redisson;

importorg.redisson.config.Config;

importorg.springframework.context.annotation.Bean;

importorg.springframework.context.annotation.Configuration;

importorg.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;

importorg.springframework.data.redis.core.RedisTemplate;

importorg.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;

importorg.springframework.data.redis.serializer.StringRedisSerializer;

importjava.io.Serializable;

@Configuration

publicclassRedisConfig{

@Bean

publicRedisTemplateString,SerializableredisTemplate(LettuceConnectionFactorylettuceConnectionFactory){

RedisTemplateString,SerializableredisTemplate=newRedisTemplate();

redisTemplate.setConnectionFactory(lettuceConnectionFactory);

//設(shè)置key序列號(hào)方式string

redisTemplate.setKeySerializer(newStringRedisSerializer());

//設(shè)置value的序列化方式j(luò)son

redisTemplate.setValueSerializer(newGenericJackson2JsonRedisSerializer());

redisTemplate.setHashKeySerializer(newStringRedisSerializer());

redisTemplate.setHashValueSerializer(newGenericJackson2JsonRedisSerializer());

redisTemplate.afterPropertiesSet();

returnredisTemplate;

@Bean

publicRedissonredisson(){

Configconfig=newConfig();

config.useSingleServer().setAddress("redis://33:6379").setDatabase(0);

return(Redisson)Redisson.create(config);

}

接口測(cè)試：

importorg.redisson.Redisson;

importorg.redisson.api.RLock;

importorg.springframework.beans.factory.annotation.Autowired;

importorg.springframework.data.redis.core.StringRedisTemplate;

importorg.springframework.web.bind.annotation.GetMapping;

importorg.springframework.web.bind.annotation.RestController;

@RestController

publicclassTestController{

@Autowired

privateStringRedisTemplatestringRedisTemplate;

@Autowired

privateRedissonredisson;

privatestaticfinalStringKEY="spike";

@GetMapping("/buy")

publicStringbugGood(){

RLockredissonLock=redisson.getLock(KEY);

redissonLock.lock();

try{

Stringresult=stringRedisTemplate.opsForValue().get("goods:001");

intgoodNumber=result==null0:Integer.parseInt(result);

if(goodNumber0){

intrealNum=goodNumber-1;

stringRedisTemplate.opsForValue().set("goods:001",realNum+"");

return"秒殺成功，剩余庫(kù)存："+realNum;

return"商品已售罄！";

}finally{

redissonLock.unlock();

}

多節(jié)點(diǎn)的情況下，代碼相同，要保證lock的key一樣

-SpringBoot集成Redisson

引入redis和redissonstarter：

!--/artifact/org.springframework.boot/spring-boot-starter-data-redis--

dependency

groupIdorg.springframework.boot/groupId

artifactIdspring-boot-starter-data-redis/artifactId

/dependency

!--/artifact/org.redisson/redisson--

dependency

groupIdorg.redisson/groupId

artifactIdredisson-spring-boot-starter/artifactId

/dependency

redis配置：

spring:

redis:

#地址

host:6

#端口，默認(rèn)為6379

port:6379

password:123456

#連接超時(shí)時(shí)間

timeout:30s

database:0

lettuce:

pool:

#連接池中的最小空閑連接

min-idle:0

#連接池中的最大空閑連接

max-idle:8

#連接池的最大數(shù)據(jù)庫(kù)連接數(shù)

max-active:8

##連接池最大阻塞等待時(shí)間（使用負(fù)值表示沒有限制）

max-wait:-1ms

redisson配置：

importorg.redisson.Redisson;

importorg.redisson.api.RedissonClient;

importorg.redisson.config.Config;

importorg.redisson.config.SingleServerConfig;

importorg.redisson.config.TransportMode;

importorg.springframework.beans.factory.annotation.Value;

importorg.springframework.context.annotation.Bean;

importorg.springframework.context.annotation.Configuration;

*redisson配置

@Configuration

publicclassRedissonConfig{

@Value("${spring.redis.host}")

privateStringhost;

@Value("${spring.redis.port}")

privateStringport;

@Value("${spring.redis.password}")

privateStringpassword;

@Bean

publicRedissonClientredissonClient(){

Configconfig=newConfig();

config.setTransportMode(TransportMode.NIO);

//單體配置，如果是SSL連接，使用rediss://

SingleServerConfigsingleServerConfig=config.useSingleServer();

singleServerConfig.setAddress("redis://"+host+":"+port);

singleServerConfig.setPassword(password);

returnRedisson.create(config);

}

使用：

importorg.redisson.api.RLock;

importorg.redisson.api.RedissonClient;

importjavax.annotation.Resource;

importjava.util.concurrent.TimeUnit;

publicclassTestController{

@Resource

privateRedissonClientredissonClient;

publicvoiddoAction1(){

StringlockKey="lockKey";

RLocklock=redissonClient.getLock(lockKey);

//加鎖，無參數(shù)

lock.lock();

//鎖有效時(shí)間，時(shí)間單位

//lock.lock(5,TimeUnit.SECONDS);

try{

//dosomething

}finally{

//解鎖

lock.unlock();

publicvoiddoAction2()throwsInterruptedException{

StringlockKey="lockKey";

RLocklock=redissonClient.getLock(lockKey);

//1.無參數(shù)，直接上鎖

//lock.tryLock();