using HibernateInterceptor with TransactionProxyFactoryBean

[bdjones]

Is there a way to use HibernateInterceptor with the TransactionProxyFactoryBean? I'm trying to apply a HibernateInterceptor to a TransactionProxyFactoryBean in the applicationsContext.xml. Does someone have an example of how to "wire-up" the interceptor to the TransactionProxyFactoryBean's postInterceptors attribute in xml? Or is the interceptor only used with a ProxyFactoryBean? Obviously, I'm new so any help would be appreciated.

[irbouho]

Since you are using TransactionProxyFactoryBean, you do not need to use HibernateInterceptor. Just configure a HibernateTransactionManager and provide it as the transactionManger of your TransactionProxyFactoryBean.

HibernateTransactionManager binds a new Hibernate Session to the thread before a method call, closing and removing it afterwards in case of any method outcome. If there already was a pre-bound Hibernate Session, HibernateTransactionManager will reuse it.

For an example of using HibernateTransactionManager, search the forums.
For an example of using HibernateInterceptor, take a look at Spring AOP with Hibernate.

HTH

[bdjones]

Well, let me back up. I want to be able to access lazily initialized collections.

Here is what I have :

A hibernate DAO class:

public class StudentDAOhbm extends HibernateDaoSupport implements StudentDAO{
    
    /** Creates a new instance of StudentDAOhbm */
    public StudentDAOhbm() {
    }
    
    public Student loadStudent(int id) {
        return (Student) getHibernateTemplate().load(Student.class, new Integer(id));
    }
    
}

The pertinent xml configuration is as follows (from both spring-servlet.xml and applicationContext.xml):

	<bean id="studentManagerTarget" class="somecompany.DAO.hbm.StudentDAOhbm">
		<property name="sessionFactory"><ref local="sessionFactory"/></property>
	</bean>

	<bean id="studentManDao" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
		<property name="transactionManager"><ref local="transactionManager"/></property>
		<property name="target"><ref local="studentManagerTarget"/></property>
		<property name="transactionAttributes">
			<props>
				<prop key="get*">PROPAGATION_REQUIRED,readOnly</prop>
				<prop key="find*">PROPAGATION_REQUIRED,readOnly</prop>
				<prop key="load*">PROPAGATION_REQUIRED,readOnly</prop>
				<prop key="store*">PROPAGATION_REQUIRED</prop>
			</props>
		</property>
	</bean>

    <bean id="studentDetailController" class="somecompany.web.StudentDetailController">
        <property name="studentMan">
            <ref bean="studentManDao"/>
        </property>
    </bean>

A controller class as follows:

public class StudentDetailController implements Controller {

    private StudentDAO studentMan;

    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

       int studentId = RequestUtils.getIntParameter(request, "studentId", 0)
    	Student student = studentMan.loadStudent(studentId);
       Set names = student.getNames();
            
        Map myModel = new HashMap();
        myModel.put("student",student);
        

        return new ModelAndView("studentDetailView", "model", myModel);
    }

Now finally the Student class

public class Student extends Person implements Serializable {

    // many other attributes

   private Set names;

    // other constructors 

    /** default constructor */
    public Student() {
    }


    public Set getNames() {
        return this.names;
    }

    public void setNames(Set names) {
        this.names = names;
    }

}

Now when I run this I get an error as follows:

net.sf.hibernate.LazyInitializationException: Failed to lazily initialize a collection - no session or session was closed

caused by the following line in the controller class :

Set names = student.getNames();

I realize that the method getNames is accessing a collection that is lazily initialized. How do I access a lazily initialized set such as the set in the example above? Is there a good example somewhere? I guess I would like some direction. Does anyone have a good idea that I can follow? Again, any help at all is greatly appreciated.

[irbouho]

You can configure a OpenSessionInViewFilter in your web.xml to keep your Hibernate Session open for View Layer.

[bdjones]

I tried the OpenSessionViewFilter in my web.xml file, and that didn't work. I get the same error as in the previous post.

I'm guessing my OpenSessionInViewFilter is not configured properly.

What am I missing?

Here is my web.xml file:

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns="http&#58;//java.sun.com/xml/ns/j2ee"
	 xmlns&#58;xsi="http&#58;//www.w3.org/2001/XMLSchema-instance"
	 xsi&#58;schemaLocation="http&#58;//java.sun.com/xml/ns/j2ee http&#58;//java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
	 version="2.4">
         
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>/WEB-INF/applicationContext-hibernate.xml</param-value>
	</context-param>
	<filter>
	<filter-name>hibernateFilter</filter-name>
	<filter-class>org.springframework.orm.hibernate.support.OpenSessionInViewFilter</filter-class>
	<init-param>
	<param-name>sessionFactoryBeanName</param-name>
	<param-value>sessionFactory</param-value>
	</init-param>
	</filter>
	<filter-mapping>
	<filter-name>hibernateFilter</filter-name>
	<url-pattern>*.jsp</url-pattern>
	</filter-mapping> 
	<listener>
	<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>

	<servlet>
		<servlet-name>context</servlet-name>
		<servlet-class>org.springframework.web.context.ContextLoaderServlet</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>
        
  <servlet>
    <servlet-name>findstudent</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>2</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>findstudent</servlet-name>
    <url-pattern>*.htm</url-pattern>
  </servlet-mapping>

    <welcome-file-list>
	<welcome-file>
            index.jsp
        </welcome-file>
    </welcome-file-list>
    
</web-app>

[irbouho]

Do you call jsp from your web agent?

<filter-mapping>
<filter-name>hibernateFilter</filter-name>
<url-pattern>*.jsp</url-pattern>
</filter-mapping>

I think that the OpenSessionInViewFilter should be mapped to

   <filter-mapping> 
     <filter-name>hibernateFilter</filter-name> 
     <url-pattern>*.htm</url-pattern> 
   </filter-mapping>

as the Hibernate Session should be opened before your controller is invoked and closed after the View has finished rendering the output.

HTH

[bdjones]

Yes, you were right. I changed the .jsp to .htm and it seems to work now.

Thank you so freaking much.