SpringCache——自定义缓存配置——如何将自定义的数据保存为json格式

我们接下来就自定义将数据保存为json格式

我们先来看源码CacheAutoConfiguration里面的@EnableConfigurationProperties(CacheProperties.class)（将所有的属性都绑定到这里面），我们的CacheAutoConfiguration源码还有如下的配置可以导入CacheConfigurations缓存的自动配置类

/**
	 * {@link ImportSelector} to add {@link CacheType} configuration classes.
	 */
	static class CacheConfigurationImportSelector implements ImportSelector {

		@Override
		public String[] selectImports(AnnotationMetadata importingClassMetadata) {
			CacheType[] types = CacheType.values();
			String[] imports = new String[types.length];
			for (int i = 0; i < types.length; i++) {
				imports[i] = CacheConfigurations.getConfigurationClass(types[i]);
			}
			return imports;
		}

	}

CacheConfigurations源码里面我们就可以导入redis相关的自动配置类RedisCacheConfiguration

		mappings.put(CacheType.REDIS, RedisCacheConfiguration.class);

总结：CacheAutoConfiguration帮我们导入了org.springframework.boot.autoconfigure.cache;RedisCacheConfiguration源代码如下

class RedisCacheConfiguration {

	@Bean
	RedisCacheManager cacheManager(CacheProperties cacheProperties, CacheManagerCustomizers cacheManagerCustomizers,
			ObjectProvider<org.springframework.data.redis.cache.RedisCacheConfiguration> redisCacheConfiguration,
			ObjectProvider<RedisCacheManagerBuilderCustomizer> redisCacheManagerBuilderCustomizers,
			RedisConnectionFactory redisConnectionFactory, ResourceLoader resourceLoader) {
		RedisCacheManagerBuilder builder = RedisCacheManager.builder(redisConnectionFactory).cacheDefaults(
				determineConfiguration(cacheProperties, redisCacheConfiguration, resourceLoader.getClassLoader()));
		List<String> cacheNames = cacheProperties.getCacheNames();
		if (!cacheNames.isEmpty()) {
			builder.initialCacheNames(new LinkedHashSet<>(cacheNames));
		}
		redisCacheManagerBuilderCustomizers.orderedStream().forEach((customizer) -> customizer.customize(builder));
		return cacheManagerCustomizers.customize(builder.build());
	}

我们继续查看上面源代码中，如下代码的源代码RedisCacheConfiguration

			ObjectProvider<org.springframework.data.redis.cache.RedisCacheConfiguration> redisCacheConfiguration,

org.springframework.data.redis.cache.RedisCacheConfiguration源代码就可以进行序列化，反序列化配置

public class RedisCacheConfiguration {
    private final Duration ttl;
    private final boolean cacheNullValues;
    private final CacheKeyPrefix keyPrefix;
    private final boolean usePrefix;
    private final SerializationPair<String> keySerializationPair;
    private final SerializationPair<Object> valueSerializationPair;
    private final ConversionService conversionService;

org.springframework.boot.autoconfigure.cache.RedisCacheConfiguration有一行代码，帮我们实现了默认配置如下

mall-product
config

@Configuration
@EnableCaching
public class MyCacheConfig {

    //缓存的序列方式自定义设置
    @Bean
    RedisCacheConfiguration redisCacheConfiguration(){

        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig();
         config = config.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(new StringRedisSerializer()));
        config=config.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(new GenericJackson2JsonRedisSerializer()));
        return config;
    }
}

修改后代码如下

@EnableConfigurationProperties(CacheProperties.class)
@Configuration
@EnableCaching
public class MyCacheConfig {

    /**
     *
     * Configuration properties for the cache abstraction.

     *1：原来和配置文件绑定的配置类是这样子的
    @ConfigurationProperties(prefix = "spring.cache")
    *public class CacheProperties {
     * 2：要让它生效
     *@EnableConfigurationProperties(CacheProperties.class)
     * 问题：配置文件中的ttl没有用上
     * @return
     */
    //缓存的序列方式自定义设置
    @Bean
    RedisCacheConfiguration redisCacheConfiguration(CacheProperties cacheProperties){

        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig();
         config = config.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(new StringRedisSerializer()));
        config=config.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(new GenericJackson2JsonRedisSerializer()));
        CacheProperties.Redis redisProperties = cacheProperties.getRedis();
        //将配置文件中的所有东西都要拿来
        if (redisProperties.getTimeToLive() != null) {
            config = config.entryTtl(redisProperties.getTimeToLive());
        }
        if (redisProperties.getKeyPrefix() != null) {
            config = config.prefixCacheNameWith(redisProperties.getKeyPrefix());
        }
        if (!redisProperties.isCacheNullValues()) {
            config = config.disableCachingNullValues();
        }
        if (!redisProperties.isUseKeyPrefix()) {
            config = config.disableKeyPrefix();
        }
        return config;
    }
}

#缓存类型
spring:
  cache:
    type: redis
    redis: 
      time-to-live: 3600000
      #如果指定了前缀，我们就用指定的前缀，如果没有就默认使用缓存的注解里面设置的    @Cacheable(value={"category"},key = "#root.method.name")

      key-prefix: CACHE_
      use-key-prefix: true 
      # 是否缓存空值，防止缓存穿透
      cache-null-value: true