一、Jedis，Redisson，Lettuce三者的區別共同點：都提供了基于Redis操作的Java API，只是封裝程度，具體實現稍有不同。

不同點：

1.1、Jedis

是Redis的Java實現的客戶端。支持基本的數據類型如：String、Hash、List、Set、Sorted Set。

特點：使用阻塞的I/O，方法調用同步，程序流需要等到socket處理完I/O才能執行，不支持異步操作。Jedis客戶端實例不是線程安全的，需要通過連接池來使用Jedis。

1.2、Redisson

優點點：分布式鎖，分布式集合，可通過Redis支持延遲隊列。

1.3、 Lettuce

用于線程安全同步，異步和響應使用，支持集群，Sentinel，管道和編碼器。

基于Netty框架的事件驅動的通信層，其方法調用是異步的。Lettuce的API是線程安全的，所以可以操作單個Lettuce連接來完成各種操作。

二、RedisTemplate2.1、使用配置

maven配置引入，（要加上版本號，我這里是因為Parent已聲明）

<dependency> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-starter-data-redisartifactId> dependency>

application-dev.yml

spring: redis: host:192.168.1.140 port:6379 password: database:15#指定redis的分庫（共16個0到15）

2.2、使用示例

@Resource privateStringRedisTemplatestringRedisTemplate; @Override publicCustomersEntityfindById(Integerid){ //需要緩存 //所有涉及的緩存都需要刪除，或者更新 try{ StringtoString=stringRedisTemplate.opsForHash().get(REDIS_CUSTOMERS_ONE,id+"").toString(); if(toString!=null){ returnJSONUtil.toBean(toString,CustomersEntity.class); } }catch(Exceptione){ e.printStackTrace(); } //緩存為空的時候，先查,然后緩存redis OptionalbyId=customerRepo.findById(id); if(byId.isPresent()){ CustomersEntitycustomersEntity=byId.get(); try{ stringRedisTemplate.opsForHash().put(REDIS_CUSTOMERS_ONE,id+"",JSONUtil.toJsonStr(customersEntity)); }catch(Exceptione){ e.printStackTrace(); } returncustomersEntity; } returnnull; }

2.3、擴展

2.3.1、spring-boot-starter-data-redis的依賴包

3.3.2、stringRedisTemplate API（部分展示）

opsForHash --》 hash操作

opsForList --》 list操作

opsForSet --》 set操作

opsForValue --》 string操作

opsForZSet --》 Zset操作

3.3.3 StringRedisTemplate默認序列化機制

publicclassStringRedisTemplateextendsRedisTemplate<String,String>{ /** *ConstructsanewStringRedisTemplateinstance.{@link#setConnectionFactory(RedisConnectionFactory)} *and{@link#afterPropertiesSet()}stillneedtobecalled. */ publicStringRedisTemplate(){ RedisSerializerstringSerializer=newStringRedisSerializer(); setKeySerializer(stringSerializer); setValueSerializer(stringSerializer); setHashKeySerializer(stringSerializer); setHashValueSerializer(stringSerializer); } }

三、RedissonClient 操作示例

3.1 基本配置

3.1.1、Maven pom 引入

<dependency> <groupId>org.springframework.bootgroupId> <artifactId>spring-boot-starter-data-redisartifactId> dependency> <dependency> <groupId>org.redissongroupId> <artifactId>redissonartifactId> <version>3.8.2version> <optional>trueoptional> dependency> <dependency> <groupId>org.redissongroupId> <artifactId>redisson-spring-boot-starterartifactId> <version>LATESTversion> dependency>

3.1.2、添加配置文件Yaml或者json格式

redisson-config.yml

#Redisson配置 singleServerConfig: address:"redis://192.168.1.140:6379" password:null clientName:null database:15#選擇使用哪個數據庫0~15 idleConnectionTimeout:10000 pingTimeout:1000 connectTimeout:10000 timeout:3000 retryAttempts:3 retryInterval:1500 reconnectionTimeout:3000 failedAttempts:3 subscriptionsPerConnection:5 subscriptionConnectionMinimumIdleSize:1 subscriptionConnectionPoolSize:50 connectionMinimumIdleSize:32 connectionPoolSize:64 dnsMonitoringInterval:5000 #dnsMonitoring:false threads:0 nettyThreads:0 codec: class:"org.redisson.codec.JsonJacksonCodec" transportMode:"NIO"

或者，配置 redisson-config.json

{ "singleServerConfig":{ "idleConnectionTimeout":10000, "pingTimeout":1000, "connectTimeout":10000, "timeout":3000, "retryAttempts":3, "retryInterval":1500, "reconnectionTimeout":3000, "failedAttempts":3, "password":null, "subscriptionsPerConnection":5, "clientName":null, "address":"redis://192.168.1.140:6379", "subscriptionConnectionMinimumIdleSize":1, "subscriptionConnectionPoolSize":50, "connectionMinimumIdleSize":10, "connectionPoolSize":64, "database":0, "dnsMonitoring":false, "dnsMonitoringInterval":5000 }, "threads":0, "nettyThreads":0, "codec":null, "useLinuxNativeEpoll":false }

3.1.3、讀取配置

新建讀取配置類

@Configuration publicclassRedissonConfig{ @Bean publicRedissonClientredisson()throwsIOException{ //兩種讀取方式，Config.fromYAML和Config.fromJSON //Configconfig=Config.fromJSON(RedissonConfig.class.getClassLoader().getResource("redisson-config.json")); Configconfig=Config.fromYAML(RedissonConfig.class.getClassLoader().getResource("redisson-config.yml")); returnRedisson.create(config); } }

或者，在 application.yml中配置如下

spring: redis: redisson: config:classpath:redisson-config.yaml

3.2 使用示例

@RestController @RequestMapping("/") publicclassTeController{ @Autowired privateRedissonClientredissonClient; staticlongi=20; staticlongsum=300; //==========================String======================= @GetMapping("/set/{key}") publicStrings1(@PathVariableStringkey){ //設置字符串 RBucketkeyObj=redissonClient.getBucket(key); keyObj.set(key+"1-v1"); returnkey; } @GetMapping("/get/{key}") publicStringg1(@PathVariableStringkey){ //設置字符串 RBucketkeyObj=redissonClient.getBucket(key); Strings=keyObj.get(); returns; } //==========================hash=======================-= @GetMapping("/hset/{key}") publicStringh1(@PathVariableStringkey){ Urur=newUr(); ur.setId(MathUtil.randomLong(1,20)); ur.setName(key); //存放Hash RMapss=redissonClient.getMap("UR"); ss.put(ur.getId().toString(),ur); returnur.toString(); } @GetMapping("/hget/{id}") publicStringh2(@PathVariableStringid){ //hash查詢 RMapss=redissonClient.getMap("UR"); Urur=ss.get(id); returnur.toString(); } //查詢所有的keys @GetMapping("/all") publicStringall(){ RKeyskeys=redissonClient.getKeys(); Iterablekeys1=keys.getKeys(); keys1.forEach(System.out::println); returnkeys.toString(); } //================================讀寫鎖測試============================= @GetMapping("/rw/set/{key}") publicvoidrw_set(){ //RedissonLock. RBucketls_count=redissonClient.getBucket("LS_COUNT"); ls_count.set("300",360000000l,TimeUnit.SECONDS); } //減法運算 @GetMapping("/jf") publicvoidjf(){ Stringkey="S_COUNT"; //RAtomicLongatomicLong=redissonClient.getAtomicLong(key); //atomicLong.set(sum); //longl=atomicLong.decrementAndGet(); //System.out.println(l); RAtomicLongatomicLong=redissonClient.getAtomicLong(key); if(!atomicLong.isExists()){ atomicLong.set(300l); } while(i==0){ if(atomicLong.get()>0){ longl=atomicLong.getAndDecrement(); try{ Thread.sleep(1000l); }catch(InterruptedExceptione){ e.printStackTrace(); } i--; System.out.println(Thread.currentThread().getName()+"->"+i+"->"+l); } } } @GetMapping("/rw/get") publicStringrw_get(){ Stringkey="S_COUNT"; Runnabler=newRunnable(){ @Override publicvoidrun(){ RAtomicLongatomicLong=redissonClient.getAtomicLong(key); if(!atomicLong.isExists()){ atomicLong.set(300l); } if(atomicLong.get()>0){ longl=atomicLong.getAndDecrement(); i--; System.out.println(Thread.currentThread().getName()+"->"+i+"->"+l); } } }; while(i!=0){ newThread(r).start(); //newThread(r).run(); //newThread(r).run(); //newThread(r).run(); //newThread(r).run(); } RBucketbucket=redissonClient.getBucket(key); Strings=bucket.get(); System.out.println("================線程已結束================================"+s); returns; } }

4.3 擴展

4.3.1 豐富的jar支持，尤其是對 Netty NIO框架

4.3.2 豐富的配置機制選擇，這里是詳細的配置說明

https://github.com/redisson/redisson/wiki/2.-Configuration

關于序列化機制中，就有很多

4.3.3 API支持（部分展示），具體的 Redis --> RedissonClient ,可查看這里

https://github.com/redisson/redisson/wiki/11.-Redis-commands-mapping

4.3.4 輕便的豐富的鎖機制的實現

Lock

Fair Lock

MultiLock

RedLock

ReadWriteLock

Semaphore

PermitExpirableSemaphore

CountDownLatch

四、基于注解實現的Redis緩存4.1 Maven 和 YML配置

參考 RedisTemplate 配置。另外，還需要額外的配置類

//todo定義序列化，解決亂碼問題 @EnableCaching @Configuration @ConfigurationProperties(prefix="spring.cache.redis") publicclassRedisCacheConfig{ privateDurationtimeToLive=Duration.ZERO; publicvoidsetTimeToLive(DurationtimeToLive){ this.timeToLive=timeToLive; } @Bean publicCacheManagercacheManager(RedisConnectionFactoryfactory){ RedisSerializerredisSerializer=newStringRedisSerializer(); Jackson2JsonRedisSerializerjackson2JsonRedisSerializer=newJackson2JsonRedisSerializer(Object.class); //解決查詢緩存轉換異常的問題 ObjectMapperom=newObjectMapper(); om.setVisibility(PropertyAccessor.ALL,JsonAutoDetect.Visibility.ANY); om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL); jackson2JsonRedisSerializer.setObjectMapper(om); //配置序列化（解決亂碼的問題） RedisCacheConfigurationconfig=RedisCacheConfiguration.defaultCacheConfig() .entryTtl(timeToLive) .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer)) .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer)) .disableCachingNullValues(); RedisCacheManagercacheManager=RedisCacheManager.builder(factory) .cacheDefaults(config) .build(); returncacheManager; } }

4.2 使用示例

@Transactional @Service publicclassReImplimplementsRedisService{ @Resource privateCustomerRepocustomerRepo; @Resource privateStringRedisTemplatestringRedisTemplate; publicstaticfinalStringREDIS_CUSTOMERS_ONE="Customers"; publicstaticfinalStringREDIS_CUSTOMERS_ALL="allList"; //=====================================================================使用Springcahce注解方式實現緩存 //==================================單個操作 @Override @Cacheable(value="cache:customer",unless="null==#result",key="#id") publicCustomersEntitycacheOne(Integerid){ finalOptionalbyId=customerRepo.findById(id); returnbyId.isPresent()?byId.get():null; } @Override @Cacheable(value="cache:customer",unless="null==#result",key="#id") publicCustomersEntitycacheOne2(Integerid){ finalOptionalbyId=customerRepo.findById(id); returnbyId.isPresent()?byId.get():null; } //todo自定義redis緩存的key, @Override @Cacheable(value="cache:customer",unless="null==#result",key="#root.methodName+'.'+#id") publicCustomersEntitycacheOne3(Integerid){ finalOptionalbyId=customerRepo.findById(id); returnbyId.isPresent()?byId.get():null; } //todo這里緩存到redis，還有響應頁面是String（加了很多轉義符,），不是Json格式 @Override @Cacheable(value="cache:customer",unless="null==#result",key="#root.methodName+'.'+#id") publicStringcacheOne4(Integerid){ finalOptionalbyId=customerRepo.findById(id); returnbyId.map(JSONUtil::toJsonStr).orElse(null); } //todo緩存json，不亂碼已處理好,調整序列化和反序列化 @Override @Cacheable(value="cache:customer",unless="null==#result",key="#root.methodName+'.'+#id") publicCustomersEntitycacheOne5(Integerid){ OptionalbyId=customerRepo.findById(id); returnbyId.filter(obj->!StrUtil.isBlankIfStr(obj)).orElse(null); } //==================================刪除緩存 @Override @CacheEvict(value="cache:customer",key="'cacheOne5'+'.'+#id") publicObjectdel(Integerid){ //刪除緩存后的邏輯 returnnull; } @Override @CacheEvict(value="cache:customer",allEntries=true) publicvoiddel(){ } @CacheEvict(value="cache:all",allEntries=true) publicvoiddelall(){ } //==================List操作 @Override @Cacheable(value="cache:all") publicListcacheList(){ Listall=customerRepo.findAll(); returnall; } //todo先查詢緩存，再校驗是否一致，然后更新操作，比較實用，要清楚緩存的數據格式（明確業務和緩存模型數據） @Override @CachePut(value="cache:all",unless="null==#result",key="#root.methodName") publicListcacheList2(){ Listall=customerRepo.findAll(); returnall; } }