Problem with Spring / Hibernate and Proxy

[TorTukiTu]

Hi all,

I am using Hibernate to insert data in a logging database.

I have got four classes to do that :

DAOLog

public class DAOLog extends AbstractDAOHibernate implements IDAOLog

It's interface : IDAOLog

	public void doSomething();
	public LogHBM createLog(Session pSession);
	public void updateLog(Session pSession, LogHBM logHBM);
	public void saveLog(Session pSession, LogHBM logHBM);

An abstract class AbstractDAOHibernate

public class AbstractDAOHibernate extends HibernateDaoSupport

And a factory : DAOHibernateFactory

public class DAOHibernateFactory implements IDAOHibernateFactory{
	
	public static final DAOHibernateFactory instance = new DAOHibernateFactory();

	private final static BeanFactory context = new ClassPathXmlApplicationContext(ResourceStringDAOHibernate.RES_SPRING_DAO_HIBERNATE_XML_FILE);
	
	private DAOHibernateFactory(){}
	
	public static DAOHibernateFactory getInstance(){
		return DAOHibernateFactory.instance;
	}

	private AbstractDAOHibernate getDAO(ResourceStringDAOHibernate.DAOHibernateEnum pEnum){
		return (AbstractDAOHibernate) context.getBean(pEnum.getLabel());
	}
	
	public IDAOLog getDAOLogging(){
		return (IDAOLog)getDAO(ResourceStringDAOHibernate.DAOHibernateEnum.LOGGING_SERVICE);
	}
	
}

Here is the UML class diagram:


Here is my applicationContext.xml

	<bean id="hibernateTemplate" class="org.springframework.orm.hibernate3.HibernateTemplate">
		<property name="sessionFactory">
			<ref bean="sessionFactory" />
		</property>
	</bean>
	
	<bean
	    id="sessionFactory"
	    class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
	    <property name="configLocation">    
	        <value>
	            hibernate/hibernate.cfg.xml
	        </value>
	    </property>
		<property name="mappingResources">
			<list>
				<value>hibernate/Log.hbm</value>
			</list>
		</property>
	</bean>
	
	<bean id="hibernateDaoSupport" abstract="true"
	class="org.springframework.orm.hibernate3.support.HibernateDaoSupport">
	<property name="sessionFactory" ref="sessionFactory"/>
	</bean>



	<!-- <bean id="hibernateDaoSupport" class=""></bean> -->
	<bean id="abstractDAOHibernate" class="com.xxx.consumer.data.Impl.AbstractDAOHibernate" abstract="true"></bean>
	
	<bean id="dAOLog"
		class="com.xxx.consumer.data.Impl.DAOLog"
		scope="singleton"
		parent="abstractDAOHibernate"
		factory-method="getInstance">
		<property name="sessionFactory" ref="sessionFactory"></property>
	</bean>

The problem:

I need to do something like this :

IDAOLog idaoLog = (IDAOLog)FacadeBuisness.getInstance().getDAOFactory().getDAOHibernateFactory().getDAOLogging();
Session vSession = ((DAOLog)idaoLog).getSessionFactory().openSession();

But I can't directly cast idaoLog to DAOLog because of the Spring Proxy.
So I am trying to use the DAOHibernateFactory to return a general type of AbstractDAOHibernate and then cast it to IDAOLog.
So I could use after getSessionFactory() on it.

But, I got the error

$Proxy56 cannot be cast to com.xxx.consumer.data.Impl.AbstractDAOHibernate
at com.xxx.consumer.data.DAOHibernateFactory.getDAO(DAOHibernateFactory.java:25)

And AbstractDAOHibernate has no Interface. So I am blocked. How should I do it? Is create an Interface for AbstractDAOHibernate the good way?

PS.: Sorry for my bad english...

[Marten Deinum]

Ehrm... Argh... Why on earth are you using hibernate, with spring, in such an ugly way... Simply use dependency injection instead of the long winded, ugly, easily breakable , hard to test lookups... Next to that don't use HibernateDaoSupport/HibernateTemplate those are deprecated in favor of a plain hibernate api. If you use spring and hibernate (and use spring to manage the transactions) don't use openSession, use getCurrentSession.

However to answer your question, enable class proxies instead of interface based proxies.

However in short, I would run from the current code base....

[TorTukiTu]

Tank you, Marten Deinum.

Do you have some links to tutorials or interresting books about it ?

I followed the http://static.springsource.org/sprin...rence/orm.html , where HibernateTemplate is still used.

I am afraid all the tutorials I made an the book I have is not up to date at all...

Tortue 974.