springboot整合redis操作缓存（将查询到的数据放在缓存中）

我就是我 2022-08-28 06:54 324阅读 0赞

### 文章目录 ###

*  1.依赖和配置：
 *  2.操作数据库（查询缓存）：
 *   *  service:
     *  controller:
     *  mapper
 *  3.结果：

# 1.依赖和配置： #

<dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-redis</artifactId>
            </dependency>

RedisConfig：

package com.english.english_vision.config;
    import com.fasterxml.jackson.annotation.JsonInclude;
    import com.fasterxml.jackson.annotation.JsonTypeInfo;
    import com.fasterxml.jackson.databind.DeserializationFeature;
    import com.fasterxml.jackson.databind.MapperFeature;
    import com.fasterxml.jackson.databind.SerializationFeature;
    import org.springframework.cache.interceptor.KeyGenerator;
    import org.springframework.data.redis.cache.RedisCacheManager;
    import com.fasterxml.jackson.annotation.JsonAutoDetect;
    import com.fasterxml.jackson.annotation.PropertyAccessor;
    import com.fasterxml.jackson.databind.ObjectMapper;
    import org.springframework.cache.CacheManager;
    import org.springframework.cache.annotation.CachingConfigurerSupport;
    import org.springframework.cache.annotation.EnableCaching;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.data.redis.cache.RedisCacheConfiguration;
    
    import org.springframework.data.redis.connection.RedisConnectionFactory;
    import org.springframework.data.redis.core.*;
    import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
    import org.springframework.data.redis.serializer.RedisSerializationContext;
    import org.springframework.data.redis.serializer.RedisSerializer;
    import org.springframework.data.redis.serializer.StringRedisSerializer;
    
    import java.lang.reflect.Method;
    import java.time.Duration;
    
    
    @EnableCaching
    @Configuration
    public class RedisConfig extends CachingConfigurerSupport { 
        private Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer() { 
            Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer =
                    new Jackson2JsonRedisSerializer<>(Object.class);
            ObjectMapper objectMapper = new ObjectMapper();
            objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
            objectMapper.configure(MapperFeature.USE_ANNOTATIONS, false);
            objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
            objectMapper.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false);
            // 此项必须配置，否则会报java.lang.ClassCastException: java.util.LinkedHashMap cannot be cast to XXX
            objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);
            objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
            jackson2JsonRedisSerializer.setObjectMapper(objectMapper);
            return jackson2JsonRedisSerializer;
        }
        @Bean
        public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) { 
            RedisTemplate<String, Object> template = new RedisTemplate<>();
            // 配置连接工厂
            template.setConnectionFactory(factory);
    
            //使用Jackson2JsonRedisSerializer来序列化和反序列化redis的value值（默认使用JDK的序列化方式）
            Jackson2JsonRedisSerializer jacksonSeial = new Jackson2JsonRedisSerializer(Object.class);
    
            ObjectMapper om = new ObjectMapper();
            // 指定要序列化的域，field,get和set,以及修饰符范围，ANY是都有包括private和public
            om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
            // 指定序列化输入的类型，类必须是非final修饰的，final修饰的类，比如String,Integer等会跑出异常
      //om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);
            jacksonSeial.setObjectMapper(om);
    
            // 值采用json序列化
            template.setValueSerializer(jacksonSeial);
            //使用StringRedisSerializer来序列化和反序列化redis的key值
            template.setKeySerializer(new StringRedisSerializer());
    
            // 设置hash key 和value序列化模式
            template.setHashKeySerializer(new StringRedisSerializer());
            template.setHashValueSerializer(jacksonSeial);
            template.afterPropertiesSet();
    
            return template;
        }
        @Bean
        public RedisCacheManager cacheManager(RedisConnectionFactory factory) { 
            RedisSerializer<String> redisSerializer = new StringRedisSerializer();
            Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
    
            //解决查询缓存转换异常的问题
            ObjectMapper om = new ObjectMapper();
            om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
    
            jackson2JsonRedisSerializer.setObjectMapper(om);
    
            //配置序列化(解决乱码的问题)
            RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
                    .entryTtl(Duration.ofDays(30))
                    .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer))
                    .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer))
                    .disableCachingNullValues();
    
            RedisCacheManager cacheManager = RedisCacheManager.builder(factory)
                    .cacheDefaults(config)
                    .build();
            return cacheManager;
        }
    
        @Bean
        public HashOperations<String, String, Object> hashOperations(RedisTemplate<String, Object> redisTemplate) { 
            return redisTemplate.opsForHash();
        }
    
        /** * 对redis字符串类型数据操作 * * @param redisTemplate * @return */
        @Bean
        public ValueOperations<String, Object> valueOperations(RedisTemplate<String, Object> redisTemplate) { 
    
            Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<Object>(Object.class);
            ObjectMapper om = new ObjectMapper();
            om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
            om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
            jackson2JsonRedisSerializer.setObjectMapper(om);
            redisTemplate.setKeySerializer(jackson2JsonRedisSerializer);
            redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
            redisTemplate.setHashKeySerializer(jackson2JsonRedisSerializer);
            redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer);
            redisTemplate.afterPropertiesSet();
    
    
    
    
            return redisTemplate.opsForValue();
        }
    
        /** * 对链表类型的数据操作 * * @param redisTemplate * @return */
        @Bean
        public ListOperations<String, Object> listOperations(RedisTemplate<String, Object> redisTemplate) { 
            return redisTemplate.opsForList();
        }
    
        /** * 对无序集合类型的数据操作 * * @param redisTemplate * @return */
        @Bean
        public SetOperations<String, Object> setOperations(RedisTemplate<String, Object> redisTemplate) { 
            return redisTemplate.opsForSet();
        }
    
        /** * 对有序集合类型的数据操作 * * @param redisTemplate * @return */
        @Bean
        public ZSetOperations<String, Object> zSetOperations(RedisTemplate<String, Object> redisTemplate) { 
            return redisTemplate.opsForZSet();
        }
    
        @Bean("myGenerator")
        public KeyGenerator keyGenerator()
        { 
            return new KeyGenerator() { 
                @Override
                public Object generate(Object target, Method method, Object... objects) { 
                    StringBuilder sb = new StringBuilder();
                    sb.append(target.getClass().getName());
                    sb.append(method.getName());
                    for(Object obj:objects)
                        sb.append(obj.toString());
                    return sb.toString();
    
    
                }
    
            };
        }
    }

# 2.操作数据库（查询缓存）： #

## service: ##

public interface ISongService extends IService<Song> { 
        List<Song> listbyName(String name);
    
    }
    
    @Service
    public class SongServiceImpl extends ServiceImpl<SongMapper, Song> implements ISongService { 
        @Autowired
        private RedisService redisService;
        @Autowired
        private SongMapper songMapper;
        @Autowired
        private RedisTemplate redisTemplate;
     @Override
        public List<Song> listbyName(String name) { 
            List<Song> songs = null;
            String key = "songlist:"+name ;
            ValueOperations<String, List<Song>> operations = redisTemplate.opsForValue();
    
            //判断redis中是否有键为key的缓存
            boolean hasKey = redisTemplate.hasKey(key);
            if(hasKey) { 
                songs = operations.get(key);
                return songs;
            }
            else { 
    songs = songMapper.listbyName(name);
    operations.set(key,songs,3, TimeUnit.HOURS);
            }
            System.out.println("mapper查询");
            return songMapper.listbyName(name);
        }
    
    }

## controller: ##

@ApiOperation(value="查询歌曲")
        @RequestMapping(value = "/query", method = RequestMethod.POST)
        public ResponseResult querySong(
                @ApiParam(name="name",value="歌名",required=true)
                @RequestParam("name")String name)
        { 
    
          // List<Song> songs = songService.listbyName(new LambdaQueryWrapper<Song>().eq(Song::getName,name));
            List<Song> songs = songService.listbyName(name);
            if(songs == null) return ResponseResult.error(ResponseEnum.DIARY_NOT_EXIST);
            List<SongVo> songVos = songs.stream().map(e->{ 
                SongVo songVo = new SongVo();
                BeanUtils.copyBeanProp(songVo,e);
                return songVo;
            }).collect(Collectors.toList());
            int numbers = songVos.size();
                    PageResult pageResult = new PageResult<>(songVos,numbers);
            return ResponseResult.success(pageResult);
        }

## mapper ##

<select id="listbyName" resultType="com.english.english_vision.pojo.Song">
            select * from t_song where name like "%"#{ name}"%"
        </select>

# 3.结果： #

![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAbWFyY2ggb2YgVGltZQ_size_20_color_FFFFFF_t_70_g_se_x_16]  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAbWFyY2ggb2YgVGltZQ_size_20_color_FFFFFF_t_70_g_se_x_16 1]  
多次发起请求只打印了一次sql,可以说明后面几次是从缓存中取出的  
查看redis数据库：  
![在这里插入图片描述][watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAbWFyY2ggb2YgVGltZQ_size_20_color_FFFFFF_t_70_g_se_x_16 2]

[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAbWFyY2ggb2YgVGltZQ_size_20_color_FFFFFF_t_70_g_se_x_16]: /images/20220828/8bff98fe3e0442959320e909bd3459a7.png
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAbWFyY2ggb2YgVGltZQ_size_20_color_FFFFFF_t_70_g_se_x_16 1]: /images/20220828/5583e3e93aba4bd3953bb93e6f52b95b.png
[watermark_type_ZHJvaWRzYW5zZmFsbGJhY2s_shadow_50_text_Q1NETiBAbWFyY2ggb2YgVGltZQ_size_20_color_FFFFFF_t_70_g_se_x_16 2]: /images/20220828/52a3ccecb0bc4e4188b91deaf7fec225.png