Spring Framework

org.springframework.orm.jpa.support
Class OpenEntityManagerInViewInterceptor

java.lang.Object
  extended by org.springframework.orm.jpa.EntityManagerFactoryAccessor
      extended by org.springframework.orm.jpa.support.OpenEntityManagerInViewInterceptor
All Implemented Interfaces:
Aware, BeanFactoryAware, WebRequestInterceptor

public class OpenEntityManagerInViewInterceptor
extends EntityManagerFactoryAccessor
implements WebRequestInterceptor

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

This interceptor makes JPA EntityManagers available via the current thread, which will be autodetected by transaction managers. It is suitable for service layer transactions via JpaTransactionManager or JtaTransactionManager as well as for non-transactional read-only execution.

In contrast to OpenEntityManagerInViewFilter, this interceptor is set up in a Spring application context and can thus take advantage of bean wiring. It inherits common JPA configuration properties from JpaAccessor, to be configured in a bean definition.

Since:
2.0
Author:
Juergen Hoeller
See Also:
OpenEntityManagerInViewFilter, JpaInterceptor, JpaTransactionManager, JpaTemplate.execute(org.springframework.orm.jpa.JpaCallback), SharedEntityManagerCreator, TransactionSynchronizationManager

Field Summary
static java.lang.String PARTICIPATE_SUFFIX
          Suffix that gets appended to the EntityManagerFactory toString representation for the "participate in existing entity manager handling" request attribute.
 
Fields inherited from class org.springframework.orm.jpa.EntityManagerFactoryAccessor
logger
 
Constructor Summary
OpenEntityManagerInViewInterceptor()
           
 
Method Summary
 void afterCompletion(WebRequest request, java.lang.Exception ex)
          Callback after completion of request processing, that is, after rendering the view.
protected  java.lang.String getParticipateAttributeName()
          Return the name of the request attribute that identifies that a request is already filtered.
 void postHandle(WebRequest request, ModelMap model)
          Intercept the execution of a request handler after its successful invocation, right before view rendering (if any).
 void preHandle(WebRequest request)
          Intercept the execution of a request handler before its invocation.
 
Methods inherited from class org.springframework.orm.jpa.EntityManagerFactoryAccessor
createEntityManager, getEntityManagerFactory, getJpaPropertyMap, getPersistenceUnitName, getTransactionalEntityManager, setBeanFactory, setEntityManagerFactory, setJpaProperties, setJpaPropertyMap, setPersistenceUnitName
 
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 EntityManagerFactory toString representation for the "participate in existing entity manager handling" request attribute.

See Also:
getParticipateAttributeName(), Constant Field Values
Constructor Detail

OpenEntityManagerInViewInterceptor

public OpenEntityManagerInViewInterceptor()
Method Detail

preHandle

public void preHandle(WebRequest request)
               throws DataAccessException
Description copied from interface: WebRequestInterceptor
Intercept the execution of a request handler before its invocation.

Allows for preparing context resources (such as a Hibernate Session) and expose them as request attributes or as thread-local objects.

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.

afterCompletion

public void afterCompletion(WebRequest request,
                            java.lang.Exception ex)
                     throws DataAccessException
Description copied from interface: WebRequestInterceptor
Callback after completion of request processing, that is, after rendering the view. Will be called on any outcome of handler execution, thus allows for proper resource cleanup.

Note: Will only be called if this interceptor's preHandle method has successfully completed!

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

getParticipateAttributeName

protected java.lang.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 EntityManagerFactory instance and appends ".FILTERED".

See Also:
PARTICIPATE_SUFFIX

Spring Framework