spring - 如何从实体管理器访问 Hibernate 统计信息？

Question

我正在使用 Spring 3.1.1.RELEASE、JUnit 4.8.1 和 Hibernate 4.1.5.Final。我正在尝试测试我的二级缓存是否配置正确，但不确定如何执行此操作。我正在使用 JPA 实体管理器，在 Spring 中配置如下...

<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="jpaDialect">
        <bean class="org.collegeboard.springboard.core.jpa.HibernateJpaDialect">
            <property name="flushMode" value="COMMIT"/>
        </bean>
    </property>
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
    </property>
    <property name="persistenceXmlLocation" value="classpath:META-INF/test-persistence.xml"/>
    <property name="persistenceUnitName" value="orgTestingDatabase"/>
    <property name="dataSource" ref="dataSource"/>
</bean>

<bean id="sharedEntityManager" class="org.springframework.orm.jpa.support.SharedEntityManagerBean">
   <property name="entityManagerFactory" ref="entityManagerFactory"/>
</bean>

我已经像这样配置了二级缓存......

    <property name="hibernate.cache.use_second_level_cache">true</property>
    <property name="hibernate.cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</property>
    <property name="hibernate.cache.provider_class">org.hibernate.cache.EhCacheProvider</property> 
    <!--  Collect stats, this is for testing if the cache is working -->
    <property name="hibernate.generate_statistics">true</property>

如何访问给定 javax.persistence.EntityManager 的 org.hibernate.stat.Statistics 对象？显然，我需要以某种方式访问​​ SessionFactory，但我无法找出适当的一系列强制转换。

谢谢，-戴夫

Answer 1

我过去一直在努力解决这个问题:Exposing Hibernate (cache) statistics through JMX with Spring in Tomcat

如果您只是想知道“它是否正常工作”，您可以为 org.hibernate.stat.Statistics 或 org.hibernate.stat.* 启用 Hibernate 调试日志记录。但是，如果您(像我一样)想要获得缓存统计报告，您可以执行以下操作。这公开了一个包含所有统计信息的 JMX bean:

/**
 * Provides code to register Hibernate's 2nd level cache statistics bean with a
 * JMX MBean server. Assumes that both the MBeanServer and the
 * EntityManagerFactory are available as Spring-managed beans. Note that while
 * registering this class enables the collection of statistics even if that was
 * previously disabled.
 */
public class HibernateCacheStatisticsJmxRegistration {

  @Autowired
  private EntityManagerFactory entityManagerFactory;

  @Autowired
  private MBeanServer mbeanServer;

  private ObjectName objectName;

  /**
   * Registers the statistics MBean that wraps a Hibernate session factory.
   * 
   * @throws JMException if anything fails..
   * @see HibernateCacheStatisticsJmxRegistration#unregister()
   */
  public void register() throws JMException {
    final SessionFactory sessionFactory = ((HibernateEntityManagerFactory) entityManagerFactory).getSessionFactory();

    objectName = new ObjectName("net.sf.ehcache:type=CacheStatistics,name=Hibernate2ndLevelCache");

    final StatisticsService statsMBean = new StatisticsService();
    statsMBean.setSessionFactory(sessionFactory);
    statsMBean.setStatisticsEnabled(true);
    mbeanServer.registerMBean(statsMBean, objectName);
  }

  /**
   * Unregisters the MBean that was registered.
   * 
   * @throws JMException if the de-registration fails
   * @see HibernateCacheStatisticsJmxRegistration#register()
   */
  public void unregister() throws JMException {
    mbeanServer.unregisterMBean(objectName);
  }
}

应用程序上下文:

<!-- Setting up Ehcache manager for various caches. -->
<bean id="ehCacheManager" class="org.springframework.cache.ehcache.EhCacheManagerFactoryBean">
  <property name="configLocation" value="classpath:ehcache.xml" />
</bean>  
<ehcache:annotation-driven cache-manager="ehCacheManager" />

<!-- Exposing cache statistics through JMX. -->
<context:mbean-server />
<bean class="net.sf.ehcache.management.ManagementService" init-method="init">
  <constructor-arg ref="ehCacheManager"/>
  <constructor-arg ref="mbeanServer"/>
  <constructor-arg value="true"/>
  <constructor-arg value="true"/>
  <constructor-arg value="true"/>
  <constructor-arg value="true"/>
</bean>    
<bean class="HibernateCacheStatisticsJmxRegistration" init-method="register" destroy-method="unregister" />