Question

I am using JPA with Hibernate 3 and Spring 3.5.
I am unable to make JPA/hibernate refresh to changes made in database in the backend outside of hibernate (via direct queries).
I am using EHCache , and second level caching. Following are the key configuration items:

<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <!-- key properties pulled from prop file -->        
    <property name="driverClass" value="${dataSource.driverClassName}"/>
    <property name="jdbcUrl" value="${dataSource.url}"/>
    <property name="user" value="${dataSource.username}"/>
    <property name="password" value="${dataSource.password}"/>
    <property name="maxPoolSize" value="50"/>
    <property name="maxIdleTime" value="14400"/>
    <property name="checkoutTimeout" value="5000"/>
    <property name="idleConnectionTestPeriod" value="60"/>
    <property name="preferredTestQuery" value="select 1"/>
    <property name="maxAdministrativeTaskTime" value="300"/>
    <property name="numHelperThreads" value="10"/>
</bean>

<!-- We are Using JPA -->
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
    <property name="dataSource" ref="dataSource"/>
    <property name="persistenceXmlLocation" value="classpath:persistence.xml"/>
    <property name="jpaProperties">
        <props>
            <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
            <prop key="hibernate.show_sql">true</prop>
            <prop key="hibernate.format_sql">true</prop>
            <prop key="hibernate.use_sql_comments">false</prop>
            <prop key="hibernate.hbm2ddl.auto">update</prop>
            <prop key="hibernate.generate_statistics">true</prop>
            <prop key="hibernate.cache.region.factory_class">net.sf.ehcache.hibernate.EhCacheRegionFactory</prop>
            <prop key="hibernate.cache.use_query_cache">true</prop>
            <prop key="hibernate.cache.use_second_level_cache">true</prop>
            <prop key="hibernate.cache.use_structured_entries">true</prop>
            <prop key="hibernate.cache.generate_statistics">true</prop>
        </props>
    </property>
    <property name="jpaVendorAdapter">
        <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"/>
    </property>
</bean>

I am also using JpaTransactionManager with Propagation=REQUIRED for all methods interacting with entities.

Please advice.

Answer 1

Changing the database through the “back door” is in contradiction to using a orm especially with a cache.

I would try to avoid this situation completely (although I know that you have needs for it).

A solution using the back door cold be:

1. Send a notification to the application using hibernate.
2. This Notification leads to an eviction of the cache (Probably the notification can contain infromation about the part of the cache to be evicted).