Trying to destroy beans in the correct order using Spring

Question

I have a web application with Spring configured to create a hibernate factory (singleton) session, as well as a session and transaction (both are request fields), but this destroys the session and transaction in the wrong order, How can I configure it so that Was the transaction destroyed before the session? Here is my Spring applicationContext.xml file:

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "http://www.springframework.org/dtd/spring-beans-2.0.dtd"> <beans> <bean id="hibernateSessionFactory" scope="singleton" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"> <property name="configLocation" value="classpath:hibernate.cfg.xml" /> </bean> <!-- The per-http request hibernate session --> <bean id="hibernateSession" factory-bean="hibernateSessionFactory" factory-method="openSession" destroy-method="close" scope="request" /> <!-- The per-http request transaction (i need this to be destroyed BEFORE the session) --> <bean id="hibernateTransaction" factory-bean="hibernateSession" factory-method="beginTransaction" destroy-method="commit" scope="request" /> </beans> 

And here is the log that shows that it closes the session before closing the transaction:

 16111 [http-8080-3] DEBUG org.springframework.beans.factory.support.DisposableBeanAdapter - Invoking destroy method 'close' on bean with name 'hibernateSession' 16111 [http-8080-3] DEBUG org.hibernate.jdbc.ConnectionManager - releasing JDBC connection [ (open PreparedStatements: 0, globally: 0) (open ResultSets: 0, globally: 0)] 16111 [http-8080-3] DEBUG com.mchange.v2.resourcepool.BasicResourcePool - trace com.mchange.v2.resourcepool.BasicResourcePool@17e4dee [managed: 4, unused: 3, excluded: 0] (eg com.mchange.v2.c3p0.impl.NewPooledConnection@19a8416 ) 16111 [http-8080-3] DEBUG org.springframework.beans.factory.support.DisposableBeanAdapter - Invoking destroy method 'commit' on bean with name 'hibernateTransaction' 16111 [http-8080-3] DEBUG org.hibernate.transaction.JDBCTransaction - commit 16111 [http-8080-3] WARN org.springframework.beans.factory.support.DisposableBeanAdapter - Invocation of destroy method 'commit' failed on bean with name 'hibernateTransaction' org.hibernate.SessionException: Session is closed 

Answer 1

It appears that the order in which the destory method is called for non-singleton bean objects is not completely controlled. From the documents ( 5.1.4 Using Dependence on ):

The dependency attribute in the component definition can indicate both the dependence of the initialization time, and, in the case of only single-element components , the corresponding dependence of the destruction time

You can create a helper object and instruct it to create and destroy your bean components:

 public class HelperObject { private SessionFactory factory; private Session session; private Transaction tx; public void init() { session = factory.createSession(); tx = session.beginTransaction(); } public void destroy() { tx.commit(); session.close(); } ... } 

-

 <bean id = "helperObject" class = "HelperObject" scope = "request" init-method = "init" destroy-method = "destroy"> <property name = "factory" ref = "hibernateSessionFactory" /> </bean> <bean id="hibernateSession" factory-bean="helperObject" factory-method="getSession" scope="request" /> <bean id="hibernateTransaction" factory-bean="helperObject" factory-method="getTransaction" scope="request" /> 

And in the end, this may not be the best way to manage Spring Hibernate sessions and transactions. Consider using Spring Hibernate's built-in and transaction support.

EDIT: Well, the right way to manage transactions is:

• You do not need binary session and transaction
• You should not call createSession for the session factory returned by org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean . You can embed this session factory in your beans and call getCurrentSession when you need a session, it will work fine.
• You can use declarative transaction management ( @Transactional annotations for transactional methods). For this to work, you must add to your config:

,

 <bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory" ref="hibernateSessionFactory"/> </bean> <tx:annotation-driven/> 

• See the links above for more information.

Answer 2

You can declare that hibernateTransaction dependent on hibernateSession . Since the container will instantiate beans in the dependency order (banning cyclic dependencies) and dump them in the reverse order, this should do the trick.

Answer 3

Transactions should be related to services if you follow the Spring idiom. Sessions are web tier objects that are completely separate from the service tier. It sounds like you made a mistake by messing up your web tier with a service tier. Better to tease them separately; you are unlikely to encounter this problem.