Configure Hibernate second-level cache

Hibernate is a popular object-relational mapping (ORM) library for the Java language that lets you store your Java object data in a relational database management system (RDBMS). Hibernate's default cache operates at the scope of a single session. This is often supplemented with a second-level cache that is shared across all sessions and persists when sessions end. You can use Hazelcast to provide a Hibernate second-level cache in your Spring application.

Enable Hazelcast as a Hibernate second-level cache provider

If you haven't already, configure a HazelcastInstance using the hazelcast namespace as described in Configure Hazelcast in Spring.

If you are using Spring Boot, the easiest way to enable Hazelcast as a Hibernate second-level cache provider is to modify your Spring application.properties file to reference a Hazelcast instance:

yaml

spring:
  jpa:
    properties:
      hibernate:
        cache:
          use_query_cache: true
          use_second_level_cache: true
          region:
            factory_class: com.hazelcast.hibernate.HazelcastLocalCacheRegionFactory
          # Hazelcast client configuration
          hazelcast:
            instance_name: my-instance
      javax:
        persistence:
          sharedCache:
            # Only entities marked with Cacheable will use 2nd level cache
            mode: ENABLE_SELECTIVE

If you are not using Spring Boot, configure your LocalSessionFactoryBean to use a Hazelcast instance by passing the Hazelcast instance name. That way, you can use the same HazelcastInstance as the Hibernate second-level cache instance:

Java

java

@Value("${hz.instance.name}")
private String hazelcastInstanceName;
@Bean
public LocalSessionFactoryBean sessionFactory() throws Exception {
    LocalSessionFactoryBean bean = new LocalSessionFactoryBean();

    Properties hibernateProperties = new Properties();
    hibernateProperties.put("hibernate.cache.region.factory_class", "com.hazelcast.hibernate.HazelcastLocalCacheRegionFactory");
    // need to specify Hazelcast connection parameter, such as instance name
    hibernateProperties.put("hibernate.cache.hazelcast.instance_name", hazelcastInstanceName);

    hibernateProperties.put("hibernate.dialect", "org.hibernate.dialect.MySQLDialect");
    bean.setHibernateProperties(hibernateProperties);
    bean.setDataSource(dataSource());
    bean.setPackagesToScan("com.example");
    return bean;
}

XML

xml

...
<bean id="sessionFactory"
      class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"
	  scope="singleton">
    <property name="dataSource" ref="dataSource"/>
    <property name="hibernateProperties">
        <props>
            ...
            <prop key="hibernate.cache.region.factory_class">com.hazelcast.hibernate.HazelcastLocalCacheRegionFactory</prop>
            <!-- need to specify Hazelcast connection parameter, such as instance name -->
            <prop key="hibernate.cache.hazelcast.instance_name">${hz.instance.name}</prop>
        </props>
    </property>
    ...
</bean>

Hibernate RegionFactory classes

Hazelcast provides the following classes for configuring Hibernate second-level cache:

• com.hazelcast.hibernate.HazelcastLocalCacheRegionFactory
• com.hazelcast.hibernate.HazelcastCacheRegionFactory

See Configuring RegionFactory in the Hazelcast Hibernate GitHub repository for more information.

Next steps

See the sample application for an example Hibernate second-level cache configuration.