对返回Hibernate对象的方法使用Spring的Cachable注释

Question

我昨天安装了Memcached，并最终使Spring @Cachable注释工作..。

这个代码块完美地缓存：

@Component("CacheProcessor")
public class CacheProcessor {
    @Cacheable(value = "defaultCache", key="'dateTime-'.concat(#anything)")
    public String getDateTime2(String anything) {
        Date d = new Date();
        String response = Long.toString(d.getTime());
        return response;
    }
}

我尝试了为每个请求调用的缓存方法：

@org.springframework.cache.annotation.Cacheable(value="defaultCache", key="username")
public static List<Session> findSessionByUserName(String username) {

    String hql = "SELECT o FROM Session AS o WHERE o.username=:username";
    TypedQuery<Session> query = Session.entityManager().createQuery(hql, Session.class);
    query.setParameter("username", username);
    return query.getResultList();

}

..。但我受到的欢迎不是缓存的结果，而是堆栈跟踪：

java.lang.IllegalStateException: Post-processor tried to replace bean instance of type [com.ahp.core.model.Session] with (proxy) object of type [com.sun.proxy.$Proxy66] - not supported for aspect-configured classes!
    at org.springframework.beans.factory.wiring.BeanConfigurerSupport.checkExposedObject(BeanConfigurerSupport.java:168)
    at org.springframework.beans.factory.wiring.BeanConfigurerSupport.configureBean(BeanConfigurerSupport.java:140)
    at org.springframework.beans.factory.aspectj.AnnotationBeanConfigurerAspect.configureBean(AnnotationBeanConfigurerAspect.aj:60)
    at org.springframework.beans.factory.aspectj.AbstractDependencyInjectionAspect.ajc$afterReturning$org_springframework_beans_factory_aspectj_AbstractDependencyInjectionAspect$2$1ea6722c(AbstractDependencyInjectionAspect.aj:91)
    at com.ahp.core.model.Session.<init>(Session.java:20)
    at com.ahp.core.model.Session.entityManager_aroundBody0(Session.java:57)
    at com.ahp.core.model.Session.entityManager(Session.java:1)
    at com.ahp.core.processor.AccountProcessor.validateSession(AccountProcessor.java:545)
    at com.ahp.core.processor.WarehouseProcessor.consume(WarehouseProcessor.java:93)
    at com.ahp.core.processor.WarehouseProcessor.consume(WarehouseProcessor.java:1)
    at com.ahp.messaging.processor.AbstractRPCConsumer.onMessage(AbstractRPCConsumer.java:32)
    at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.onMessage(MessageListenerAdapter.java:228)
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:756)
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:679)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$001(SimpleMessageListenerContainer.java:82)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$1.invokeListener(SimpleMessageListenerContainer.java:167)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.invokeListener(SimpleMessageListenerContainer.java:1241)
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:660)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.doReceiveAndExecute(SimpleMessageListenerContainer.java:1005)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.receiveAndExecute(SimpleMessageListenerContainer.java:989)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$700(SimpleMessageListenerContainer.java:82)
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.run(SimpleMessageListenerContainer.java:1103)
    at java.lang.Thread.run(Thread.java:744)

如果有用的话，下面是会话类的一个片段，它是由Spring生成的，然后使用强制重构，我去掉了所有的AspectJ，所以现在它只是一个单独的Java类：

@Entity
@Configurable
//@RooJavaBean
//@RooToString
//@RooJpaActiveRecord
public class Session {

    @PersistenceContext
    transient EntityManager entityManager;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "id")
    private Long id;

    @Version
    @Column(name = "version")
    private Integer version;

    @ManyToOne
    private Account account;

    @ManyToOne
    private Company company;

    @Column(name = "qusername")
    private String username;

    ....

如果删除Configurable注释，实体管理器将不会被注入并引发一个IllegalStateException。

    public static final EntityManager entityManager() {
        EntityManager em = new Session().entityManager;
        if (em == null)
            throw new IllegalStateException("Entity manager has not been injected (is the Spring Aspects JAR configured as an AJC/AJDT aspects library?)");
        return em;
    }

如何使缓存在aspect-configured类上工作？

如果这是不可能的，那么让它在没有任何方面的情况下工作的过程是什么(假设这会使它不受影响)？

工作溶液

必须创建一个SessionService接口：

@RooService(domainTypes = {Session.class })
public interface SessionService {
    public List<Session> findSessionByUserName(String username);
}

SessionServiceImpl：

@Component
public class SessionServiceImpl implements SessionService {
    @Override
    @Cacheable(value="defaultCache", key="#username")
    public List<Session> findSessionByUserName(String username) {
        return Session.findSessionByUserName(username);
    }
}

必须将会话类修改为可序列化，并返回Roo注释。

@Entity
@RooJavaBean
@RooToString
@Configurable
@RooJpaActiveRecord
public class Session implements Serializable {
   ...
}

然后使用我的自动头发的SessionService：

@Autowired
SessionService sessionService;

我现在可以使用缓存：

sessionService.findSessionByUserName(...)

Answer 1

问题在于，您正在尝试将缓存添加到静态方法(在Roo ActiveRecord模式中所做的方式)。您必须在bean方法(非静态)上配置缓存层。

一种方法可以是使用Roo生成在实体层和Web层之间创建服务层(查看Roo文档)。这个实用工具创建了Spring，它调用Roo实体方法并修改Contoller方法来使用它。因此，您可以用@Cacheable注释此Service的方法，以便在需要时使用缓存。

祝好运!