org.springframework.orm.hibernate.support
Class OpenSessionInViewInterceptor

java.lang.Object
  extended byorg.springframework.orm.hibernate.HibernateAccessor
      extended byorg.springframework.orm.hibernate.support.OpenSessionInViewInterceptor
All Implemented Interfaces:
HandlerInterceptor, InitializingBean

public class OpenSessionInViewInterceptor
extends HibernateAccessor
implements HandlerInterceptor

Spring web HandlerInterceptor that binds a Hibernate Session to the thread for the whole processing of the request. Intended for the "Open Session in View" pattern, i.e. to allow for lazy loading in web views despite the original transactions already being completed.

This interceptor works similar to the AOP HibernateInterceptor: It just makes Hibernate Sessions available via the thread. It is suitable for non-transactional execution but also for middle tier transactions via HibernateTransactionManager or JtaTransactionManager. In the latter case, Sessions pre-bound by this interceptor will automatically be used for the transactions and flushed accordingly.

In contrast to OpenSessionInViewFilter, this interceptor is set up in a Spring application context and can thus take advantage of bean wiring. It derives from HibernateAccessor to inherit common Hibernate configuration properties.

WARNING: Applying this interceptor to existing logic can cause issues that have not appeared before, through the use of a single Hibernate Session for the processing of an entire request. In particular, the reassociation of persistent objects with a Hibernate Session has to occur at the very beginning of request processing, to avoid clashes will already loaded instances of the same objects.

NOTE: This interceptor will by default not flush the Hibernate session, as it assumes to be used in combination with middle tier transactions that care for the flushing, or HibernateAccessors with flushMode FLUSH_EAGER. If you want this interceptor to flush after the handler has been invoked but before view rendering, set the flushMode of this interceptor to FLUSH_AUTO in such a scenario.

Since:
06.12.2003
Author:
Juergen Hoeller
See Also:
HibernateAccessor.setFlushMode(int), OpenSessionInViewFilter, HibernateInterceptor, HibernateTransactionManager

Field Summary
 
Fields inherited from class org.springframework.orm.hibernate.HibernateAccessor
FLUSH_AUTO, FLUSH_EAGER, FLUSH_NEVER, logger
 
Constructor Summary
OpenSessionInViewInterceptor()
          Create a new OpenSessionInViewInterceptor, turning the default flushMode to FLUSH_NEVER.
 
Method Summary
 void afterCompletion(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, java.lang.Object handler, java.lang.Exception ex)
          Unbinds the Hibernate Session from the thread and closes it.
 void postHandle(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, java.lang.Object handler, ModelAndView modelAndView)
          Flushes the Hibernate Session before view rendering, if necessary.
 boolean preHandle(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, java.lang.Object handler)
          Opens a new Hibernate Session according to the settings of this HibernateAccessor and binds in to the thread via TransactionSynchronizationManager.
 
Methods inherited from class org.springframework.orm.hibernate.HibernateAccessor
afterPropertiesSet, convertHibernateAccessException, convertJdbcAccessException, flushIfNecessary, getEntityInterceptor, getFlushMode, getJdbcExceptionTranslator, getSessionFactory, setEntityInterceptor, setFlushMode, setFlushModeName, setJdbcExceptionTranslator, setSessionFactory
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

OpenSessionInViewInterceptor

public OpenSessionInViewInterceptor()
Create a new OpenSessionInViewInterceptor, turning the default flushMode to FLUSH_NEVER.

See Also:
HibernateAccessor.setFlushMode(int)
Method Detail

preHandle

public boolean preHandle(javax.servlet.http.HttpServletRequest request,
                         javax.servlet.http.HttpServletResponse response,
                         java.lang.Object handler)
                  throws DataAccessException
Opens a new Hibernate Session according to the settings of this HibernateAccessor and binds in to the thread via TransactionSynchronizationManager.

Specified by:
preHandle in interface HandlerInterceptor
Parameters:
request - current HTTP request
response - current HTTP response
handler - chosen handler to execute, for type and/or instance evaluation
Returns:
true if the execution chain should proceed with the next interceptor respectively the handler itself. Else, DispatcherServlet assumes that this interceptor has already dealt with the response itself.
Throws:
DataAccessException
See Also:
SessionFactoryUtils.getSession(net.sf.hibernate.SessionFactory, boolean), TransactionSynchronizationManager

postHandle

public void postHandle(javax.servlet.http.HttpServletRequest request,
                       javax.servlet.http.HttpServletResponse response,
                       java.lang.Object handler,
                       ModelAndView modelAndView)
                throws DataAccessException
Flushes the Hibernate Session before view rendering, if necessary. Set the flushMode of this HibernateAccessor to FLUSH_NEVER to avoid this extra flushing.

Specified by:
postHandle in interface HandlerInterceptor
Parameters:
request - current HTTP request
response - current HTTP response
handler - chosen handler to execute, for type and/or instance examination
modelAndView - the ModelAndView that the handler returned, can also be null
Throws:
DataAccessException
See Also:
HibernateAccessor.setFlushMode(int)

afterCompletion

public void afterCompletion(javax.servlet.http.HttpServletRequest request,
                            javax.servlet.http.HttpServletResponse response,
                            java.lang.Object handler,
                            java.lang.Exception ex)
                     throws DataAccessException
Unbinds the Hibernate Session from the thread and closes it.

Specified by:
afterCompletion in interface HandlerInterceptor
Parameters:
request - current HTTP request
response - current HTTP response
handler - chosen handler to execute, for type and/or instance examination
ex - exception thrown on handler execution
Throws:
DataAccessException
See Also:
SessionFactoryUtils.closeSessionIfNecessary(net.sf.hibernate.Session, net.sf.hibernate.SessionFactory), TransactionSynchronizationManager


Copyright (C) 2003-2004 The Spring Framework Project.