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public class: OpenSessionInViewInterceptor [javadoc | source]

All Implemented Interfaces:
    HandlerInterceptor, InitializingBean

Spring web HandlerInterceptor 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 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.

Alternatively, turn this interceptor 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).

NOTE: This interceptor 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 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. Note that the flushMode of this interceptor will just apply in single session mode!

Field Summary
public static final  String PARTICIPATE_SUFFIX    Suffix that gets appended to the SessionFactory toString representation for the "participate in existing session handling" request attribute. 
Fields inherited from org.springframework.orm.hibernate.HibernateAccessor:
 public OpenSessionInViewInterceptor() 
Method from org.springframework.orm.hibernate.support.OpenSessionInViewInterceptor Summary:
afterCompletion,   getParticipateAttributeName,   isSingleSession,   postHandle,   preHandle,   setSingleSession
Methods from org.springframework.orm.hibernate.HibernateAccessor:
afterPropertiesSet,   convertHibernateAccessException,   convertJdbcAccessException,   flushIfNecessary,   getEntityInterceptor,   getFlushMode,   getJdbcExceptionTranslator,   getSessionFactory,   setEntityInterceptor,   setFlushMode,   setFlushModeName,   setJdbcExceptionTranslator,   setSessionFactory
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.springframework.orm.hibernate.support.OpenSessionInViewInterceptor Detail:
 public  void afterCompletion(HttpServletRequest request,
    HttpServletResponse response,
    Object handler,
    Exception ex) throws DataAccessException 
    Unbind the Hibernate Session from the thread and closes it (in single session mode), or process deferred close for all sessions that have been opened during the current request (in deferred close mode).
 protected String getParticipateAttributeName() 
    Return the name of the request attribute that identifies that a request is already filtered. Default implementation takes the toString representation of the SessionFactory instance and appends ".PARTICIPATE".
 protected boolean isSingleSession() 
    Return whether to use a single session for each request.
 public  void postHandle(HttpServletRequest request,
    HttpServletResponse response,
    Object handler,
    ModelAndView modelAndView) throws DataAccessException 
    Flush the Hibernate Session before view rendering, if necessary. Note that this just applies in single session mode!

    The default is FLUSH_NEVER to avoid this extra flushing, assuming that middle tier transactions have flushed their changes on commit.

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