SpringBoot实战电商项目mall(30k+star)地址: https://github.com/macrozheng/mall
Spring Data Redis 是Spring 框架提供的用于操作Redis的方式,最近整理了下它的用法,解决了使用过程中遇到的一些难点与坑点,希望对大家有所帮助。本文涵盖了Redis的安装、Spring Cache结合Redis的使用、Redis连接池的使用和RedisTemplate的使用等内容。
这里提供Linux和Windows两种安装方式,由于Windows下的版本最高只有3.2版本,所以推荐使用Linux下的版本,目前最新稳定版本为5.0,也是本文中使用的版本。
这里我们使用Docker环境下的安装方式。
docker pull redis:5.0
docker run -p 6379:6379 --name redis / -v /mydata/redis/data:/data / -d redis:5.0 redis-server --appendonly yes
想使用Windows版本的朋友可以使用以下安装方式。
当Spring Boot 结合Redis来作为缓存使用时,最简单的方式就是使用Spring Cache了,使用它我们无需知道Spring中对Redis的各种操作,仅仅通过它提供的@Cacheable 、@CachePut 、@CacheEvict 、@EnableCaching等注解就可以实现缓存功能。
开启缓存功能,一般放在启动类上。
使用该注解的方法当缓存存在时,会从缓存中获取数据而不执行方法,当缓存不存在时,会执行方法并把返回结果存入缓存中。 一般使用在查询方法上
,可以设置如下属性:
使用该注解的方法每次执行时都会把返回结果存入缓存中。 一般使用在新增方法上
,可以设置如下属性:
使用该注解的方法执行时会清空指定的缓存。 一般使用在更新或删除方法上
,可以设置如下属性:
<!--redis依赖配置--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency>
spring: redis: host: 192.168.6.139 # Redis服务器地址 database: 0 # Redis数据库索引(默认为0) port: 6379 # Redis服务器连接端口 password: # Redis服务器连接密码(默认为空) timeout: 1000ms # 连接超时时间
@EnableCaching @SpringBootApplication public class MallTinyApplication { public static void main(String[] args) { SpringApplication.run(MallTinyApplication.class, args); } }
/** * PmsBrandService实现类 * Created by macro on 2019/4/19. */ @Service public class PmsBrandServiceImpl implements PmsBrandService { @Autowired private PmsBrandMapper brandMapper; @CacheEvict(value = RedisConfig.REDIS_KEY_DATABASE, key = "'pms:brand:'+#id") @Override public int update(Long id, PmsBrand brand) { brand.setId(id); return brandMapper.updateByPrimaryKeySelective(brand); } @CacheEvict(value = RedisConfig.REDIS_KEY_DATABASE, key = "'pms:brand:'+#id") @Override public int delete(Long id) { return brandMapper.deleteByPrimaryKey(id); } @Cacheable(value = RedisConfig.REDIS_KEY_DATABASE, key = "'pms:brand:'+#id", unless = "#result==null") @Override public PmsBrand getItem(Long id) { return brandMapper.selectByPrimaryKey(id); } }
此时我们就会想到有没有什么办法让Redis中存储的数据变成标准的JSON格式,然后可以设置一定的过期时间,不设置过期时间容易产生很多不必要的缓存数据。
/** * Redis配置类 * Created by macro on 2020/3/2. */ @EnableCaching @Configuration public class RedisConfig extends CachingConfigurerSupport { /** * redis数据库自定义key */ public static final String REDIS_KEY_DATABASE="mall"; @Bean public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) { RedisSerializer<Object> serializer = redisSerializer(); RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>(); redisTemplate.setConnectionFactory(redisConnectionFactory); redisTemplate.setKeySerializer(new StringRedisSerializer()); redisTemplate.setValueSerializer(serializer); redisTemplate.setHashKeySerializer(new StringRedisSerializer()); redisTemplate.setHashValueSerializer(serializer); redisTemplate.afterPropertiesSet(); return redisTemplate; } @Bean public RedisSerializer<Object> redisSerializer() { //创建JSON序列化器 Jackson2JsonRedisSerializer<Object> serializer = new Jackson2JsonRedisSerializer<>(Object.class); ObjectMapper objectMapper = new ObjectMapper(); objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY); objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL); serializer.setObjectMapper(objectMapper); return serializer; } @Bean public RedisCacheManager redisCacheManager(RedisConnectionFactory redisConnectionFactory) { RedisCacheWriter redisCacheWriter = RedisCacheWriter.nonLockingRedisCacheWriter(redisConnectionFactory); //设置Redis缓存有效期为1天 RedisCacheConfiguration redisCacheConfiguration = RedisCacheConfiguration.defaultCacheConfig() .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer())).entryTtl(Duration.ofDays(1)); return new RedisCacheManager(redisCacheWriter, redisCacheConfiguration); } }
SpringBoot 1.5.x版本Redis客户端默认是Jedis实现的,SpringBoot 2.x版本中默认客户端是用Lettuce实现的,我们先来了解下Jedis和Lettuce客户端。
Jedis在实现上是直连Redis服务,多线程环境下非线程安全,除非使用连接池,为每个 RedisConnection 实例增加物理连接。
Lettuce是一种可伸缩,线程安全,完全非阻塞的Redis客户端,多个线程可以共享一个RedisConnection,它利用Netty NIO框架来高效地管理多个连接,从而提供了异步和同步数据访问方式,用于构建非阻塞的反应性应用程序。
spring: redis: lettuce: pool: max-active: 8 # 连接池最大连接数 max-idle: 8 # 连接池最大空闲连接数 min-idle: 0 # 连接池最小空闲连接数 max-wait: -1ms # 连接池最大阻塞等待时间,负值表示没有限制
<dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> </dependency>
Caused by: java.lang.NoClassDefFoundError: org/apache/commons/pool2/impl/GenericObjectPoolConfig at org.springframework.data.redis.connection.lettuce.LettucePoolingClientConfiguration$LettucePoolingClientConfigurationBuilder.<init>(LettucePoolingClientConfiguration.java:84) ~[spring-data-redis-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.data.redis.connection.lettuce.LettucePoolingClientConfiguration.builder(LettucePoolingClientConfiguration.java:48) ~[spring-data-redis-2.1.5.RELEASE.jar:2.1.5.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration$PoolBuilderFactory.createBuilder(LettuceConnectionConfiguration.java:149) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration.createBuilder(LettuceConnectionConfiguration.java:107) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration.getLettuceClientConfiguration(LettuceConnectionConfiguration.java:93) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration.redisConnectionFactory(LettuceConnectionConfiguration.java:74) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration$$EnhancerBySpringCGLIB$$5caa7e47.CGLIB$redisConnectionFactory$0(<generated>) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration$$EnhancerBySpringCGLIB$$5caa7e47$$FastClassBySpringCGLIB$$b8ae2813.invoke(<generated>) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) ~[spring-core-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:363) ~[spring-context-5.1.5.RELEASE.jar:5.1.5.RELEASE] at org.springframework.boot.autoconfigure.data.redis.LettuceConnectionConfiguration$$EnhancerBySpringCGLIB$$5caa7e47.redisConnectionFactory(<generated>) ~[spring-boot-autoconfigure-2.1.3.RELEASE.jar:2.1.3.RELEASE] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_91] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_91] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_91] at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_91] at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE] ... 111 common frames omitted
Spring Cache 给我们提供了操作Redis缓存的便捷方法,但是也有很多局限性。比如说我们想单独设置一个缓存值的有效期怎么办?我们并不想缓存方法的返回值,我们想缓存方法中产生的中间值怎么办?此时我们就需要用到RedisTemplate这个类了,接下来我们来讲下如何通过RedisTemplate来自由操作Redis中的缓存。
定义Redis操作业务类,在Redis中有几种数据结构,比如普通结构(对象),Hash结构、Set结构、List结构,该接口中定义了大多数常用操作方法。
/** * redis操作Service * Created by macro on 2020/3/3. */ public interface RedisService { /** * 保存属性 */ void set(String key, Object value, long time); /** * 保存属性 */ void set(String key, Object value); /** * 获取属性 */ Object get(String key); /** * 删除属性 */ Boolean del(String key); /** * 批量删除属性 */ Long del(List<String> keys); /** * 设置过期时间 */ Boolean expire(String key, long time); /** * 获取过期时间 */ Long getExpire(String key); /** * 判断是否有该属性 */ Boolean hasKey(String key); /** * 按delta递增 */ Long incr(String key, long delta); /** * 按delta递减 */ Long decr(String key, long delta); /** * 获取Hash结构中的属性 */ Object hGet(String key, String hashKey); /** * 向Hash结构中放入一个属性 */ Boolean hSet(String key, String hashKey, Object value, long time); /** * 向Hash结构中放入一个属性 */ void hSet(String key, String hashKey, Object value); /** * 直接获取整个Hash结构 */ Map<Object, Object> hGetAll(String key); /** * 直接设置整个Hash结构 */ Boolean hSetAll(String key, Map<String, Object> map, long time); /** * 直接设置整个Hash结构 */ void hSetAll(String key, Map<String, Object> map); /** * 删除Hash结构中的属性 */ void hDel(String key, Object... hashKey); /** * 判断Hash结构中是否有该属性 */ Boolean hHasKey(String key, String hashKey); /** * Hash结构中属性递增 */ Long hIncr(String key, String hashKey, Long delta); /** * Hash结构中属性递减 */ Long hDecr(String key, String hashKey, Long delta); /** * 获取Set结构 */ Set<Object> sMembers(String key); /** * 向Set结构中添加属性 */ Long sAdd(String key, Object... values); /** * 向Set结构中添加属性 */ Long sAdd(String key, long time, Object... values); /** * 是否为Set中的属性 */ Boolean sIsMember(String key, Object value); /** * 获取Set结构的长度 */ Long sSize(String key); /** * 删除Set结构中的属性 */ Long sRemove(String key, Object... values); /** * 获取List结构中的属性 */ List<Object> lRange(String key, long start, long end); /** * 获取List结构的长度 */ Long lSize(String key); /** * 根据索引获取List中的属性 */ Object lIndex(String key, long index); /** * 向List结构中添加属性 */ Long lPush(String key, Object value); /** * 向List结构中添加属性 */ Long lPush(String key, Object value, long time); /** * 向List结构中批量添加属性 */ Long lPushAll(String key, Object... values); /** * 向List结构中批量添加属性 */ Long lPushAll(String key, Long time, Object... values); /** * 从List结构中移除属性 */ Long lRemove(String key, long count, Object value); }
RedisService的实现类,使用RedisTemplate来自由操作Redis中的缓存数据。
/** * redis操作实现类 * Created by macro on 2020/3/3. */ @Service public class RedisServiceImpl implements RedisService { @Autowired private RedisTemplate<String, Object> redisTemplate; @Override public void set(String key, Object value, long time) { redisTemplate.opsForValue().set(key, value, time, TimeUnit.SECONDS); } @Override public void set(String key, Object value) { redisTemplate.opsForValue().set(key, value); } @Override public Object get(String key) { return redisTemplate.opsForValue().get(key); } @Override public Boolean del(String key) { return redisTemplate.delete(key); } @Override public Long del(List<String> keys) { return redisTemplate.delete(keys); } @Override public Boolean expire(String key, long time) { return redisTemplate.expire(key, time, TimeUnit.SECONDS); } @Override public Long getExpire(String key) { return redisTemplate.getExpire(key, TimeUnit.SECONDS); } @Override public Boolean hasKey(String key) { return redisTemplate.hasKey(key); } @Override public Long incr(String key, long delta) { return redisTemplate.opsForValue().increment(key, delta); } @Override public Long decr(String key, long delta) { return redisTemplate.opsForValue().increment(key, -delta); } @Override public Object hGet(String key, String hashKey) { return redisTemplate.opsForHash().get(key, hashKey); } @Override public Boolean hSet(String key, String hashKey, Object value, long time) { redisTemplate.opsForHash().put(key, hashKey, value); return expire(key, time); } @Override public void hSet(String key, String hashKey, Object value) { redisTemplate.opsForHash().put(key, hashKey, value); } @Override public Map<Object, Object> hGetAll(String key) { return redisTemplate.opsForHash().entries(key); } @Override public Boolean hSetAll(String key, Map<String, Object> map, long time) { redisTemplate.opsForHash().putAll(key, map); return expire(key, time); } @Override public void hSetAll(String key, Map<String, Object> map) { redisTemplate.opsForHash().putAll(key, map); } @Override public void hDel(String key, Object... hashKey) { redisTemplate.opsForHash().delete(key, hashKey); } @Override public Boolean hHasKey(String key, String hashKey) { return redisTemplate.opsForHash().hasKey(key, hashKey); } @Override public Long hIncr(String key, String hashKey, Long delta) { return redisTemplate.opsForHash().increment(key, hashKey, delta); } @Override public Long hDecr(String key, String hashKey, Long delta) { return redisTemplate.opsForHash().increment(key, hashKey, -delta); } @Override public Set<Object> sMembers(String key) { return redisTemplate.opsForSet().members(key); } @Override public Long sAdd(String key, Object... values) { return redisTemplate.opsForSet().add(key, values); } @Override public Long sAdd(String key, long time, Object... values) { Long count = redisTemplate.opsForSet().add(key, values); expire(key, time); return count; } @Override public Boolean sIsMember(String key, Object value) { return redisTemplate.opsForSet().isMember(key, value); } @Override public Long sSize(String key) { return redisTemplate.opsForSet().size(key); } @Override public Long sRemove(String key, Object... values) { return redisTemplate.opsForSet().remove(key, values); } @Override public List<Object> lRange(String key, long start, long end) { return redisTemplate.opsForList().range(key, start, end); } @Override public Long lSize(String key) { return redisTemplate.opsForList().size(key); } @Override public Object lIndex(String key, long index) { return redisTemplate.opsForList().index(key, index); } @Override public Long lPush(String key, Object value) { return redisTemplate.opsForList().rightPush(key, value); } @Override public Long lPush(String key, Object value, long time) { Long index = redisTemplate.opsForList().rightPush(key, value); expire(key, time); return index; } @Override public Long lPushAll(String key, Object... values) { return redisTemplate.opsForList().rightPushAll(key, values); } @Override public Long lPushAll(String key, Long time, Object... values) { Long count = redisTemplate.opsForList().rightPushAll(key, values); expire(key, time); return count; } @Override public Long lRemove(String key, long count, Object value) { return redisTemplate.opsForList().remove(key, count, value); } }
测试RedisService中缓存操作的Controller,大家可以调用测试下。
/** * Redis测试Controller * Created by macro on 2020/3/3. */ @Api(tags = "RedisController", description = "Redis测试") @Controller @RequestMapping("/redis") public class RedisController { @Autowired private RedisService redisService; @Autowired private PmsBrandService brandService; @ApiOperation("测试简单缓存") @RequestMapping(value = "/simpleTest", method = RequestMethod.GET) @ResponseBody public CommonResult<PmsBrand> simpleTest() { List<PmsBrand> brandList = brandService.list(1, 5); PmsBrand brand = brandList.get(0); String key = "redis:simple:" + brand.getId(); redisService.set(key, brand); PmsBrand cacheBrand = (PmsBrand) redisService.get(key); return CommonResult.success(cacheBrand); } @ApiOperation("测试Hash结构的缓存") @RequestMapping(value = "/hashTest", method = RequestMethod.GET) @ResponseBody public CommonResult<PmsBrand> hashTest() { List<PmsBrand> brandList = brandService.list(1, 5); PmsBrand brand = brandList.get(0); String key = "redis:hash:" + brand.getId(); Map<String, Object> value = BeanUtil.beanToMap(brand); redisService.hSetAll(key, value); Map<Object, Object> cacheValue = redisService.hGetAll(key); PmsBrand cacheBrand = BeanUtil.mapToBean(cacheValue, PmsBrand.class, true); return CommonResult.success(cacheBrand); } @ApiOperation("测试Set结构的缓存") @RequestMapping(value = "/setTest", method = RequestMethod.GET) @ResponseBody public CommonResult<Set<Object>> setTest() { List<PmsBrand> brandList = brandService.list(1, 5); String key = "redis:set:all"; redisService.sAdd(key, (Object[]) ArrayUtil.toArray(brandList, PmsBrand.class)); redisService.sRemove(key, brandList.get(0)); Set<Object> cachedBrandList = redisService.sMembers(key); return CommonResult.success(cachedBrandList); } @ApiOperation("测试List结构的缓存") @RequestMapping(value = "/listTest", method = RequestMethod.GET) @ResponseBody public CommonResult<List<Object>> listTest() { List<PmsBrand> brandList = brandService.list(1, 5); String key = "redis:list:all"; redisService.lPushAll(key, (Object[]) ArrayUtil.toArray(brandList, PmsBrand.class)); redisService.lRemove(key, 1, brandList.get(0)); List<Object> cachedBrandList = redisService.lRange(key, 0, 3); return CommonResult.success(cachedBrandList); } }
https://github.com/macrozheng/mall-learning/tree/master/mall-tiny-redis
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