SpringBoot缓存使用Redis配合SpringCache来使用

我会带着你远行 2024-02-17 10:31 23阅读 0赞

## 一、配置类缓存 ##

### 1、引入依赖 ###

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

### 2、写配置类 ###

**注意要注入容器**

@Configuration
    public class RedisConfig {
    
        @Bean
        public CacheManager cacheManager(LettuceConnectionFactory connectionFactory){
            //定义序列化器
            GenericJackson2JsonRedisSerializer genericJackson2JsonRedisSerializer = 
                     new GenericJackson2JsonRedisSerializer();
            StringRedisSerializer stringRedisSerializer = new StringRedisSerializer();
    
    
            RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
                    //过期时间600秒
                    .entryTtl(Duration.ofSeconds(600))
                    // 配置序列化
                    .serializeKeysWith(RedisSerializationContext.SerializationPair
                    .fromSerializer(stringRedisSerializer))
                    .serializeValuesWith(RedisSerializationContext.SerializationPair
                    .fromSerializer(genericJackson2JsonRedisSerializer));
    
            RedisCacheManager cacheManager = RedisCacheManager.builder(connectionFactory)
                    .cacheDefaults(config)
                    .build();
    
            return cacheManager;
        }
    }

### 3、 在具体方法上加@Cacheable ###

@Cacheable(value = "category", key = "'all'")
        @Override
        public List<Category> findCategoryTree() {
            //这底下的是你查询的某些逻辑，根据自己的来写
            List<Category> categoryList = categoryMapper.findAll();
            List<Category> oneCategoryList = buildCategoryTree(categoryList, 0L);
            return oneCategoryList;
    
        }

### 4、启动类开启缓存 ###

@EnableCaching

## 二、手动缓存 ##

### 1、直接代码实现，因为很简单 ###

@Autowired
        private RedisTemplate<String,String> redisTemplate;
    
        @Override
        public List<Category> findOneCategory() {
    
            //1,从redis中查找一级分类
            String categoryListJson = redisTemplate.opsForValue().get("category:one");
            //判断查出来的是否存在，存在将json转成list返回
            if (StringUtils.hasText(categoryListJson)){
                List<Category> existCategoryList = JSON.parseArray(categoryListJson, Category.class);
                return existCategoryList;
            }
            //没有将一级分类通过数据库查，并添加到redis中缓存
            List<Category> categoryList = categoryMapper.findOneCategory();
            redisTemplate.opsForValue().set("category:one",JSON.toJSONString(categoryList),60, TimeUnit.MINUTES);
            return categoryList;
        }

解释一下上面代码，首先直接从redis中读取category:one,查看是否有数据。如果有数据，把redis中的json数据转成list返回给前端。如果没有数据，那就设置

>     redisTemplate.opsForValue().set("category:one",JSON.toJSONString(categoryList),60, TimeUnit.MINUTES);
> 
> category:one k
> 
> JSON.toJSONString(categoryList) v
> 
> 60 过期时间  
> TimeUnit.MINUTES 时间单位

[SpringCache学习链接][SpringCache] 这个博主写的很好可以去看看

[SpringCache]: https://blog.csdn.net/m0_62946761/article/details/129368226