SpringBoot缓存

目录

缓存支持

 缓存集成

redis缓存集成

缓存支持

Spring 框架只提供抽象，不提供具体的缓存存储，底层需要依赖第三方存储组件，如果当前应用没有注册CacheManager 或者 CacheResolver 实例，Spring Boot 会按以下缓存组件的顺序来检测:

1. Generic
2. JCache (SR-107)(EhCache 3, Hazelcast, Infinispan 等等)
3. Hazelcast
4. lnfinispan
5. Couchbase
6. redis

........

Spring Boot的自动配置类为：CacheAutoConfiguration，在 CacheAutoConfiguration 缓存自动配置类中引入了 CacheConfigurationImportSelector 配置选择器：

@AutoConfiguration(after = { CouchbaseDataAutoConfiguration.class, HazelcastAutoConfiguration.class,
		HibernateJpaAutoConfiguration.class, RedisAutoConfiguration.class })
@ConditionalOnClass(CacheManager.class)
@ConditionalOnBean(CacheAspectSupport.class)
@ConditionalOnMissingBean(value = CacheManager.class, name = "cacheResolver")
@EnableConfigurationProperties(CacheProperties.class)
@Import({ CacheConfigurationImportSelector.class, CacheManagerEntityManagerFactoryDependsOnPostProcessor.class })
public class CacheAutoConfiguration {
 
    ...
 
	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;
    }
 
}

该选择器通过 CacheConfiqurations 缓存配置类来选择对应缓存组件的配置类：

final class CacheConfigurations {
 
	private static final Map<CacheType, String> MAPPINGS;
 
	static {
		Map<CacheType, String> mappings = new EnumMap<>(CacheType.class);
		mappings.put(CacheType.GENERIC, GenericCacheConfiguration.class.getName());
		mappings.put(CacheType.HAZELCAST, HazelcastCacheConfiguration.class.getName());
		mappings.put(CacheType.INFINISPAN, InfinispanCacheConfiguration.class.getName());
		mappings.put(CacheType.JCACHE, JCacheCacheConfiguration.class.getName());
		mappings.put(CacheType.COUCHBASE, CouchbaseCacheConfiguration.class.getName());
		mappings.put(CacheType.REDIS, RedisCacheConfiguration.class.getName());
		mappings.put(CacheType.CAFFEINE, CaffeineCacheConfiguration.class.getName());
		mappings.put(CacheType.CACHE2K, Cache2kCacheConfiguration.class.getName());
		mappings.put(CacheType.SIMPLE, SimpleCacheConfiguration.class.getName());
		mappings.put(CacheType.NONE, NoOpCacheConfiguration.class.getName());
		MAPPINGS = Collections.unmodifiableMap(mappings);
	}
    
	...代码...
 
}

 缓存集成

依赖配置：

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

加入依赖后，通过使用@EnableCaching注解来启用缓存功能。通过参数type指定要使用的缓存组件，以redis为示例：

spring:
  cache: 
    type: redis

禁用缓存

spring:
  cache: 
    type: none

 缓存类型type的值

• GENERIC: 通用缓存类型
• HAZELCAST: Hazelcast 缓存类型
• INFINISPAN: Infinispan 缓存类型
• JCACHE: JCache 缓存类型
• COUCHBASE: Couchbase 缓存类型
• REDIS: Redis 缓存类型
• CAFFEINE: Caffeine 缓存类型
• CACHE2K: Cache2k 缓存类型
• SIMPLE: 简单缓存类型
• NONE: 无缓存类型

redis缓存集成

在Spring Boot 2.7中使用@EnableCaching注解启用缓存功能时，如果你想使用Redis作为缓存存储，你需要在配置文件中指定Redis的相关配置。

application.properties或application.yml文件中添加以下配置：

 
spring:
  cache:
    type: redis # 指定缓存使用redis
  redis:
    host: 127.0.0.1 # Redis服务器地址
    database: 1 # 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）

依赖配置：

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

 配置缓存管理器：

@Configuration
@EnableCaching
public class RedisTemplateConfiguration {
    /**
     * 默认过期时长，单位：秒
     */
    @Getter
    private long expire = 60 * 60 * 24;
​
    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setKeySerializer(RedisSerializer.string());
        redisTemplate.setHashKeySerializer(RedisSerializer.string());
        redisTemplate.setValueSerializer(RedisSerializer.java());
        redisTemplate.setHashValueSerializer(RedisSerializer.java());
        redisTemplate.setConnectionFactory(factory);
        return redisTemplate;
    }
​
    @Bean
    public HashOperations<String, String, Object> hashOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForHash();
    }
​
    @Bean
    public ValueOperations<String, String> valueOperations(RedisTemplate<String, String> redisTemplate) {
        return redisTemplate.opsForValue();
    }
​
    @Bean
    public ListOperations<String, Object> listOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForList();
    }
​
    @Bean
    public SetOperations<String, Object> setOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForSet();
    }
​
    @Bean
    public ZSetOperations<String, Object> zSetOperations(RedisTemplate<String, Object> redisTemplate) {
        return redisTemplate.opsForZSet();
    }
}