Spring Framework

org.springframework.orm.hibernate4.support
Class OpenSessionInViewInterceptor

java.lang.Object
  extended by org.springframework.orm.hibernate4.support.OpenSessionInViewInterceptor
All Implemented Interfaces:
AsyncWebRequestInterceptor, WebRequestInterceptor

public class OpenSessionInViewInterceptor
extends java.lang.Object
implements AsyncWebRequestInterceptor

Spring web request interceptor that binds a Hibernate Session to the thread for the entire processing of the request.

This class is a concrete expression of the "Open Session in View" pattern, which is a pattern that allows for the lazy loading of associations in web views despite the original transactions already being completed.

This interceptor makes Hibernate Sessions available via the current thread, which will be autodetected by transaction managers. It is suitable for service layer transactions via HibernateTransactionManager as well as for non-transactional execution (if configured appropriately).

NOTE: This interceptor will by default not flush the Hibernate Session, with the flush mode being set to FlushMode.NEVER. It assumes that it will be used in combination with service layer transactions that handle the flushing: the active transaction manager will temporarily change the flush mode to FlushMode.AUTO during a read-write transaction, with the flush mode reset to FlushMode.NEVER at the end of each transaction. If you intend to use this interceptor without transactions, consider changing the default flush mode (through the "flushMode" property).

In contrast to OpenSessionInViewFilter, this interceptor is configured in a Spring application context and can thus take advantage of bean wiring..

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 with already loaded instances of the same objects.

Since:
3.1
Author:
Juergen Hoeller
See Also:
#setSingleSession, #setFlushMode, OpenSessionInViewFilter, HibernateTransactionManager, TransactionSynchronizationManager

Field Summary
protected  org.apache.commons.logging.Log logger
           
static java.lang.String PARTICIPATE_SUFFIX
          Suffix that gets appended to the SessionFactory toString() representation for the "participate in existing session handling" request attribute.
 
Constructor Summary
OpenSessionInViewInterceptor()
           
 
Method Summary
 void afterCompletion(WebRequest request, java.lang.Exception ex)
          Unbind the Hibernate Session from the thread and close it).
 AbstractDelegatingCallable getAsyncCallable(WebRequest request)
          Create a Callable to bind the Hibernate session to the async request thread.
protected  java.lang.String getParticipateAttributeName()
          Return the name of the request attribute that identifies that a request is already intercepted.
 org.hibernate.SessionFactory getSessionFactory()
           
protected  org.hibernate.Session openSession()
          Open a Session for the SessionFactory that this interceptor uses.
 void postHandle(WebRequest request, ModelMap model)
          Intercept the execution of a request handler after its successful invocation, right before view rendering (if any).
 void postHandleAsyncStarted(WebRequest request)
          Unbind the Hibernate Session from the main thread leaving it open for further use from an async thread.
 void preHandle(WebRequest request)
          Open a new Hibernate Session according to the settings of this HibernateAccessor and bind it to the thread via the TransactionSynchronizationManager.
 void setSessionFactory(org.hibernate.SessionFactory sessionFactory)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

PARTICIPATE_SUFFIX

public static final java.lang.String PARTICIPATE_SUFFIX
Suffix that gets appended to the SessionFactory toString() representation for the "participate in existing session handling" request attribute.

See Also:
getParticipateAttributeName(), Constant Field Values

logger

protected final org.apache.commons.logging.Log logger
Constructor Detail

OpenSessionInViewInterceptor

public OpenSessionInViewInterceptor()
Method Detail

setSessionFactory

public void setSessionFactory(org.hibernate.SessionFactory sessionFactory)

getSessionFactory

public org.hibernate.SessionFactory getSessionFactory()

preHandle

public void preHandle(WebRequest request)
               throws DataAccessException
Open a new Hibernate Session according to the settings of this HibernateAccessor and bind it to the thread via the TransactionSynchronizationManager.

Specified by:
preHandle in interface WebRequestInterceptor
Parameters:
request - the current web request
Throws:
DataAccessException

postHandle

public void postHandle(WebRequest request,
                       ModelMap model)
Description copied from interface: WebRequestInterceptor
Intercept the execution of a request handler after its successful invocation, right before view rendering (if any).

Allows for modifying context resources after successful handler execution (for example, flushing a Hibernate Session).

Specified by:
postHandle in interface WebRequestInterceptor
Parameters:
request - the current web request
model - the map of model objects that will be exposed to the view (may be null). Can be used to analyze the exposed model and/or to add further model attributes, if desired.

getAsyncCallable

public AbstractDelegatingCallable getAsyncCallable(WebRequest request)
Create a Callable to bind the Hibernate session to the async request thread.

Specified by:
getAsyncCallable in interface AsyncWebRequestInterceptor
Returns:
a Callable instance or null

postHandleAsyncStarted

public void postHandleAsyncStarted(WebRequest request)
Unbind the Hibernate Session from the main thread leaving it open for further use from an async thread.

Specified by:
postHandleAsyncStarted in interface AsyncWebRequestInterceptor

afterCompletion

public void afterCompletion(WebRequest request,
                            java.lang.Exception ex)
                     throws DataAccessException
Unbind the Hibernate Session from the thread and close it).

Specified by:
afterCompletion in interface WebRequestInterceptor
Parameters:
request - the current web request
ex - exception thrown on handler execution, if any
Throws:
DataAccessException
See Also:
TransactionSynchronizationManager

openSession

protected org.hibernate.Session openSession()
                                     throws DataAccessResourceFailureException
Open a Session for the SessionFactory that this interceptor uses.

The default implementation delegates to the SessionFactory.openSession method and sets the Session's flush mode to "MANUAL".

Returns:
the Session to use
Throws:
DataAccessResourceFailureException - if the Session could not be created
See Also:
FlushMode.MANUAL

getParticipateAttributeName

protected java.lang.String getParticipateAttributeName()
Return the name of the request attribute that identifies that a request is already intercepted.

The default implementation takes the toString() representation of the SessionFactory instance and appends PARTICIPATE_SUFFIX.


Spring Framework