org.springframework.orm.jpa.support
Class OpenEntityManagerInViewFilter

java.lang.Object
  extended by org.springframework.web.filter.GenericFilterBean
      extended by org.springframework.web.filter.OncePerRequestFilter
          extended by org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter
All Implemented Interfaces:
javax.servlet.Filter, BeanNameAware, DisposableBean, InitializingBean, ServletContextAware

public class OpenEntityManagerInViewFilter
extends OncePerRequestFilter

Servlet 2.3 Filter 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 filter 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.

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

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

Field Summary
static java.lang.String DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME
           
 
Fields inherited from class org.springframework.web.filter.OncePerRequestFilter
ALREADY_FILTERED_SUFFIX
 
Fields inherited from class org.springframework.web.filter.GenericFilterBean
logger
 
Constructor Summary
OpenEntityManagerInViewFilter()
           
 
Method Summary
protected  javax.persistence.EntityManager createEntityManager(javax.persistence.EntityManagerFactory emf)
          Create a JPA EntityManager to be bound to a request.
protected  void doFilterInternal(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response, javax.servlet.FilterChain filterChain)
          Same contract as for doFilter, but guaranteed to be just invoked once per request.
protected  java.lang.String getEntityManagerFactoryBeanName()
          Return the bean name of the EntityManagerFactory to fetch from Spring's root application context.
protected  javax.persistence.EntityManagerFactory lookupEntityManagerFactory()
          Look up the EntityManagerFactory that this filter should use.
protected  javax.persistence.EntityManagerFactory lookupEntityManagerFactory(javax.servlet.http.HttpServletRequest request)
          Look up the EntityManagerFactory that this filter should use, taking the current HTTP request as argument.
 void setEntityManagerFactoryBeanName(java.lang.String entityManagerFactoryBeanName)
          Set the bean name of the EntityManagerFactory to fetch from Spring's root application context.
 
Methods inherited from class org.springframework.web.filter.OncePerRequestFilter
doFilter, getAlreadyFilteredAttributeName, shouldNotFilter
 
Methods inherited from class org.springframework.web.filter.GenericFilterBean
addRequiredProperty, afterPropertiesSet, destroy, getFilterConfig, getFilterName, getServletContext, init, initBeanWrapper, initFilterBean, setBeanName, setServletContext
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME

public static final java.lang.String DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME
See Also:
Constant Field Values
Constructor Detail

OpenEntityManagerInViewFilter

public OpenEntityManagerInViewFilter()
Method Detail

setEntityManagerFactoryBeanName

public void setEntityManagerFactoryBeanName(java.lang.String entityManagerFactoryBeanName)
Set the bean name of the EntityManagerFactory to fetch from Spring's root application context. Default is "entityManagerFactory".

See Also:
DEFAULT_PERSISTENCE_MANAGER_FACTORY_BEAN_NAME

getEntityManagerFactoryBeanName

protected java.lang.String getEntityManagerFactoryBeanName()
Return the bean name of the EntityManagerFactory to fetch from Spring's root application context.


doFilterInternal

protected void doFilterInternal(javax.servlet.http.HttpServletRequest request,
                                javax.servlet.http.HttpServletResponse response,
                                javax.servlet.FilterChain filterChain)
                         throws javax.servlet.ServletException,
                                java.io.IOException
Description copied from class: OncePerRequestFilter
Same contract as for doFilter, but guaranteed to be just invoked once per request. Provides HttpServletRequest and HttpServletResponse arguments instead of the default ServletRequest and ServletResponse ones.

Specified by:
doFilterInternal in class OncePerRequestFilter
Throws:
javax.servlet.ServletException
java.io.IOException

lookupEntityManagerFactory

protected javax.persistence.EntityManagerFactory lookupEntityManagerFactory(javax.servlet.http.HttpServletRequest request)
Look up the EntityManagerFactory that this filter should use, taking the current HTTP request as argument.

Default implementation delegates to the lookupEntityManagerFactory without arguments.

Returns:
the EntityManagerFactory to use
See Also:
lookupEntityManagerFactory()

lookupEntityManagerFactory

protected javax.persistence.EntityManagerFactory lookupEntityManagerFactory()
Look up the EntityManagerFactory that this filter should use. The default implementation looks for a bean with the specified name in Spring's root application context.

Returns:
the EntityManagerFactory to use
See Also:
getEntityManagerFactoryBeanName()

createEntityManager

protected javax.persistence.EntityManager createEntityManager(javax.persistence.EntityManagerFactory emf)
Create a JPA EntityManager to be bound to a request.

Can be overridden in subclasses.

Parameters:
emf - the EntityManagerFactory to use
See Also:
EntityManagerFactory.createEntityManager()