Spring 5.3.23/Spring Boot2.7.0中如何为CacheErrorHandler注入Bean？

方式一：实现CachingConfigurer接口并注入依赖 #

你可以在实现CachingConfigurer的配置类中直接注入所需依赖，配置类本身是Spring管理的Bean，完全支持依赖注入，之后在errorHandler()方法中创建带依赖的自定义CacheErrorHandler实例即可：

@Configuration
@EnableCaching
public class CacheConfig implements CachingConfigurer {

    private final SomeDependency someDependency;

    // 构造注入（推荐方式）
    public CacheConfig(SomeDependency someDependency) {
        this.someDependency = someDependency;
    }

    @Override
    public CacheErrorHandler errorHandler() {
        // 传入依赖创建自定义错误处理器
        return new CustomCacheErrorHandler(someDependency);
    }
}

方式二：直接声明CacheErrorHandler类型的Bean #

在Spring Boot 2.7.0（对应Spring Framework 5.3.23）版本中，直接声明CacheErrorHandler类型的Bean会被缓存自动配置识别并优先使用，无需实现CachingConfigurer接口。

比如用@Component标记自定义错误处理器：

@Component
public class CustomCacheErrorHandler implements CacheErrorHandler {

    private final SomeDependency someDependency;

    public CustomCacheErrorHandler(SomeDependency someDependency) {
        this.someDependency = someDependency;
    }

    @Override
    public void handleCacheGetError(RuntimeException exception, Cache cache, Object key) {
        // 使用依赖处理缓存读取错误，比如日志记录、告警
        someDependency.recordCacheError("读取缓存失败，key: " + key, exception);
    }

    @Override
    public void handleCachePutError(RuntimeException exception, Cache cache, Object key, Object value) {
        someDependency.recordCacheError("写入缓存失败，key: " + key, exception);
    }

    @Override
    public void handleCacheEvictError(RuntimeException exception, Cache cache, Object key) {
        someDependency.recordCacheError("删除缓存失败，key: " + key, exception);
    }

    @Override
    public void handleCacheClearError(RuntimeException exception, Cache cache) {
        someDependency.recordCacheError("清空缓存失败", exception);
    }
}

也可以用@Bean在配置类中声明：

@Configuration
public class CacheBeanConfig {

    @Bean
    public CacheErrorHandler cacheErrorHandler(SomeDependency someDependency) {
        return new CustomCacheErrorHandler(someDependency);
    }
}

只要该Bean存在于Spring容器中，缓存基础设施就会自动使用它，替代默认的SimpleCacheErrorHandler。

内容的提问来源于stack exchange，提问作者James