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我们要求每个 userId-sessionID 对最多缓存 2 个类别的请求。我们计划将 EhCache 用于这种方法。该项目是一个弹簧启动应用程序。

@Cacheable(value="products")
ProductList getProducts(String userID, String sessionID, String categoryID) {
   return getProductListForThisUserAndSessionAndCategory(userId, sessionId, categoryId;) 
}

问题是当每个用户和会话 ID 对可能有多个类别时，如何将限制设置为每个 userID-sessionId 最多 2 个缓存元素？
一种方法： 设置 sessionId 和 userID 的部分键，并创建一个自定义缓存，每个 sessionID-userID 键最多可以接受两个值。EhCache 如何支持自定义缓存？
还有其他方法吗？

4

1 回答 1

2

如果我的问题正确，您将更改要缓存的最大映射数，您可以像这样配置

import org.ehcache.config.builders.CacheConfigurationBuilder;
import org.ehcache.config.builders.ResourcePoolsBuilder;
import org.ehcache.expiry.Duration;
import org.ehcache.expiry.Expirations;
import org.ehcache.jsr107.Eh107Configuration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.autoconfigure.cache.JCacheManagerCustomizer;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.annotation.PreDestroy;
import java.util.concurrent.TimeUnit;


@Configuration
@EnableCaching
public class CacheConfiguration {

    private final Logger log = LoggerFactory.getLogger(CacheConfiguration.class);
    private final javax.cache.configuration.Configuration<Object, Object> jcacheConfiguration;


    @PreDestroy
    public void destroy() {
        log.info("Remove Cache Manager metrics");
        log.info("Closing Cache Manager");
    }

    public CacheConfiguration(JHipsterProperties jHipsterProperties) {

        jcacheConfiguration = Eh107Configuration.fromEhcacheCacheConfiguration(
                CacheConfigurationBuilder.newCacheConfigurationBuilder(Object.class, Object.class,
                        ResourcePoolsBuilder.heap(2))
                        .withExpiry(Expirations.timeToLiveExpiration(Duration.of(3600, TimeUnit.SECONDS)))
                        .build()
        );
    }

    @Bean
    public JCacheManagerCustomizer cacheManagerCustomizer() {
        log.debug("Starting Ehcache");

        return cm -> {
            cm.createCache("products", jcacheConfiguration);
        };
    }

}
于 2017-12-07T17:38:49.163 回答