org.hibernate.LazyInitializationException Again and Please Help

[pingudebian]

Hi All

I am just learning about spring + hibernate on normal application (Swing) everything run smoothly until lazyloading problem
here is the error
3703 [main] ERROR org.hibernate.LazyInitializationException - failed to lazily initialize a collection of role: com.jimmy.quoteonline.pojo.Division.categories - no session or session was closed

now i have trying to change my applicationContext.xml

now like this

<bean id="hibernateInterceptor" class="org.springframework.orm.hibernate3.Hibernat eInterceptor">
<property name="sessionFactory">
<ref bean="sessionFactory" />
</property>
</bean>
<bean id="maintenanceServiceTarget" class="com.acompany.MaintenanceServiceImpl">
<property name="categoryDao"><ref bean="categoryDao" /></property>
<property name="divisionDao"><ref bean="divisionDao" /></property>
</bean>
<bean id="maintenanceService" class="org.springframework.aop.framework.ProxyFact oryBean">
<property name="target">
<ref bean="maintenanceServiceTarget" />
</property>
<property name="proxyInterfaces">
<value>com.acompany.MaintenanceService</value>
</property>
<property name="interceptorNames">
<list>
<value>hibernateInterceptor</value>
</list>
</property>
</bean>

is anyone can please please help me?

Spring + Hibernate should be extremely easy but with this lazy it is throwing more trouble that it should be

please help

many thanks in advance

[Rod Johnson]

Lazy loading is really an ORM issue rather than a Spring issue. Yes, it is one of the trickier challenges when using any ORM product.

I suggest the following choices of options:

1. Eagerly load the relationship in your Hibernate mappings. (Probably not the best performing option); OR
2. Use a fetch join to retrieve the data eagerly for your use case (modify HQL or use a Criteria query); OR
3. "Touch" the associated data within your service layer before data is returned to the web tier outside a transaction to ensure it's materialized; OR
4. Use the Open Session in View approach, with Spring's Open Session in View Filter or HandlerInterceptor. This will allow lazy-loaded data still to be retrieved in the web tier, even after the transaction has been closed.