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org.springframework.orm.hibernate.support
public class: OpenSessionInViewFilter [javadoc | source]
java.lang.Object
   org.springframework.web.filter.GenericFilterBean
      org.springframework.web.filter.OncePerRequestFilter
         org.springframework.orm.hibernate.support.OpenSessionInViewFilter

All Implemented Interfaces:
    Filter, DisposableBean, BeanNameAware, InitializingBean, ServletContextAware

Servlet 2.3 Filter that binds a Hibernate Session to the thread for the entire 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 filter 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 filter will automatically be used for the transactions and flushed accordingly.

WARNING: Applying this filter 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.

Alternatively, turn this filter into deferred close mode, by specifying "singleSession"="false": It will not use a single session per request then, but rather let each data access operation or transaction use its own session (like without Open Session in View). Each of those sessions will be registered for deferred close, though, actually processed at request completion.

A single session per request allows for most efficient first-level caching, but can cause side effects, for example on saveOrUpdate or if continuing after a rolled-back transaction. The deferred close strategy is as safe as no Open Session in View in that respect, while still allowing for lazy loading in views (but not providing a first-level cache for the entire request).

Looks up the SessionFactory in Spring's root web application context. Supports a "sessionFactoryBeanName" filter init-param; the default bean name is "sessionFactory". Looks up the SessionFactory on each request, to avoid initialization order issues (when using ContextLoaderServlet, the root application context will get initialized after this filter).

NOTE: This filter will by default not flush the Hibernate session, as it assumes to be used in combination with business layer transactions that care for the flushing, or HibernateAccessors with flushMode FLUSH_EAGER. If you want this filter to flush after completed request processing, override closeSession and invoke flush on the Session before closing it. Note that closeSession will just be invoked in single session mode!

Field Summary
public static final  String DEFAULT_SESSION_FACTORY_BEAN_NAME     
Fields inherited from org.springframework.web.filter.OncePerRequestFilter:
ALREADY_FILTERED_SUFFIX
Fields inherited from org.springframework.web.filter.GenericFilterBean:
logger
Method from org.springframework.orm.hibernate.support.OpenSessionInViewFilter Summary:
closeSession,   doFilterInternal,   getSession,   getSessionFactoryBeanName,   isSingleSession,   lookupSessionFactory,   lookupSessionFactory,   setSessionFactoryBeanName,   setSingleSession
Methods from org.springframework.web.filter.OncePerRequestFilter:
doFilter,   doFilterInternal,   getAlreadyFilteredAttributeName,   shouldNotFilter
Methods from org.springframework.web.filter.GenericFilterBean:
addRequiredProperty,   afterPropertiesSet,   destroy,   getFilterConfig,   getFilterName,   getServletContext,   init,   initBeanWrapper,   initFilterBean,   setBeanName,   setServletContext
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.springframework.orm.hibernate.support.OpenSessionInViewFilter Detail:
 protected  void closeSession(Session session,
    SessionFactory sessionFactory) 
    Close the given Session. Note that this just applies in single session mode!

    The default implementation delegates to SessionFactoryUtils' closeSessionIfNecessary method.

    Can be overridden in subclasses, e.g. for flushing the Session before closing it. See class-level javadoc for a discussion of flush handling. Note that you should also override getSession accordingly, to set the flush mode to something else than NEVER.

 protected  void doFilterInternal(HttpServletRequest request,
    HttpServletResponse response,
    FilterChain filterChain) throws ServletException, IOException 
 protected Session getSession(SessionFactory sessionFactory) throws DataAccessResourceFailureException 
    Get a Session for the SessionFactory that this filter uses. Note that this just applies in single session mode!

    The default implementation delegates to SessionFactoryUtils' getSession method and sets the Session's flushMode to NEVER.

    Can be overridden in subclasses for creating a Session with a custom entity interceptor or JDBC exception translator.

 protected String getSessionFactoryBeanName() 
    Return the bean name of the SessionFactory to fetch from Spring's root application context.
 protected boolean isSingleSession() 
    Return whether to use a single session for each request.
 protected SessionFactory lookupSessionFactory() 
    Look up the SessionFactory that this filter should use.

    Default implementation looks for a bean with the specified name in Spring's root application context.

 protected SessionFactory lookupSessionFactory(HttpServletRequest request) 
    Look up the SessionFactory that this filter should use, taking the current HTTP request as argument.

    Default implementation delegates to the lookupSessionFactory without arguments.

 public  void setSessionFactoryBeanName(String sessionFactoryBeanName) 
    Set the bean name of the SessionFactory to fetch from Spring's root application context. Default is "sessionFactory".
 public  void setSingleSession(boolean singleSession) 
    Set whether to use a single session for each request. Default is true.

    If set to false, each data access operation or transaction will use its own session (like without Open Session in View). Each of those sessions will be registered for deferred close, though, actually processed at request completion.