java.lang.Object
- org.springframework.web.filter.GenericFilterBean
- - org.springframework.web.filter.OncePerRequestFilter
  - - org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter

All Implemented Interfaces:
Filter, Aware, BeanNameAware, DisposableBean, InitializingBean, EnvironmentAware, EnvironmentCapable, ServletContextAware
```
public class OpenEntityManagerInViewFilter
extends OncePerRequestFilter
```
Servlet 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 an "entityManagerFactoryBeanName" filter init-param in web.xml; the default bean name is "entityManagerFactory". As an alternative, the "persistenceUnitName" init-param allows for retrieval by logical unit name (as specified in persistence.xml).
Since:
2.0
Author:
Juergen Hoeller
See Also:
OpenEntityManagerInViewInterceptor, JpaTransactionManager, SharedEntityManagerCreator, TransactionSynchronizationManager

Field Summary
Fields
Modifier and Type Field Description
static String DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME
Default EntityManagerFactory bean name: "entityManagerFactory".
- Fields inherited from class org.springframework.web.filter.OncePerRequestFilter
  ALREADY_FILTERED_SUFFIX
- Fields inherited from class org.springframework.web.filter.GenericFilterBean
  logger

Constructor Summary
Constructors
Constructor Description
OpenEntityManagerInViewFilter()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected EntityManager`	`createEntityManager(EntityManagerFactory emf)`	Create a JPA EntityManager to be bound to a request.
`protected void`	`doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)`	Same contract as for `doFilter`, but guaranteed to be just invoked once per request within a single request thread.
`protected String`	`getEntityManagerFactoryBeanName()`	Return the bean name of the EntityManagerFactory to fetch from Spring's root application context.
`protected String`	`getPersistenceUnitName()`	Return the name of the persistence unit to access the EntityManagerFactory for, if any.
`protected EntityManagerFactory`	`lookupEntityManagerFactory()`	Look up the EntityManagerFactory that this filter should use.
`protected EntityManagerFactory`	`lookupEntityManagerFactory(HttpServletRequest request)`	Look up the EntityManagerFactory that this filter should use, taking the current HTTP request as argument.
`void`	`setEntityManagerFactoryBeanName(String entityManagerFactoryBeanName)`	Set the bean name of the EntityManagerFactory to fetch from Spring's root application context.
`void`	`setPersistenceUnitName(String persistenceUnitName)`	Set the name of the persistence unit to access the EntityManagerFactory for.
`protected boolean`	`shouldNotFilterAsyncDispatch()`	Returns "false" so that the filter may re-bind the opened `EntityManager` to each asynchronously dispatched thread and postpone closing it until the very last asynchronous dispatch.
`protected boolean`	`shouldNotFilterErrorDispatch()`	Returns "false" so that the filter may provide an `EntityManager` to each error dispatches.

Methods inherited from class org.springframework.web.filter.OncePerRequestFilter
doFilter, getAlreadyFilteredAttributeName, isAsyncDispatch, isAsyncStarted, shouldNotFilter

Methods inherited from class org.springframework.web.filter.GenericFilterBean
addRequiredProperty, afterPropertiesSet, createEnvironment, destroy, getEnvironment, getFilterConfig, getFilterName, getServletContext, init, initBeanWrapper, initFilterBean, setBeanName, setEnvironment, setServletContext

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME
```
public static final String DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME
```
    Default EntityManagerFactory bean name: "entityManagerFactory". Only applies when no "persistenceUnitName" param has been specified.
    See Also:
    setEntityManagerFactoryBeanName(java.lang.String), setPersistenceUnitName(java.lang.String), Constant Field Values
- Constructor Detail
  - OpenEntityManagerInViewFilter
```
public OpenEntityManagerInViewFilter()
```
- Method Detail
  - setEntityManagerFactoryBeanName
```
public void setEntityManagerFactoryBeanName(String entityManagerFactoryBeanName)
```
    Set the bean name of the EntityManagerFactory to fetch from Spring's root application context.
    Default is "entityManagerFactory". Note that this default only applies when no "persistenceUnitName" param has been specified.
    See Also:
    setPersistenceUnitName(java.lang.String), DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME
  - getEntityManagerFactoryBeanName
```
protected String getEntityManagerFactoryBeanName()
```
    Return the bean name of the EntityManagerFactory to fetch from Spring's root application context.
  - setPersistenceUnitName
```
public void setPersistenceUnitName(String persistenceUnitName)
```
    Set the name of the persistence unit to access the EntityManagerFactory for.
    This is an alternative to specifying the EntityManagerFactory by bean name, resolving it by its persistence unit name instead. If no bean name and no persistence unit name have been specified, we'll check whether a bean exists for the default bean name "entityManagerFactory"; if not, a default EntityManagerFactory will be retrieved through finding a single unique bean of type EntityManagerFactory.
    See Also:
    setEntityManagerFactoryBeanName(java.lang.String), DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME
  - getPersistenceUnitName
```
protected String getPersistenceUnitName()
```
    Return the name of the persistence unit to access the EntityManagerFactory for, if any.
  - shouldNotFilterAsyncDispatch
```
protected boolean shouldNotFilterAsyncDispatch()
```
    Returns "false" so that the filter may re-bind the opened EntityManager to each asynchronously dispatched thread and postpone closing it until the very last asynchronous dispatch.
    Overrides:
    shouldNotFilterAsyncDispatch in class OncePerRequestFilter
  - shouldNotFilterErrorDispatch
```
protected boolean shouldNotFilterErrorDispatch()
```
    Returns "false" so that the filter may provide an EntityManager to each error dispatches.
    Overrides:
    shouldNotFilterErrorDispatch in class OncePerRequestFilter
  - doFilterInternal
```
protected void doFilterInternal(HttpServletRequest request,
                                HttpServletResponse response,
                                FilterChain filterChain)
                         throws ServletException,
                                IOException
```
    Description copied from class: OncePerRequestFilter
    Same contract as for doFilter, but guaranteed to be just invoked once per request within a single request thread. See OncePerRequestFilter.shouldNotFilterAsyncDispatch() for details.
    Provides HttpServletRequest and HttpServletResponse arguments instead of the default ServletRequest and ServletResponse ones.
    Specified by:
    doFilterInternal in class OncePerRequestFilter
    Throws:
    ServletException
    IOException
  - lookupEntityManagerFactory
```
protected EntityManagerFactory lookupEntityManagerFactory(HttpServletRequest request)
```
    Look up the EntityManagerFactory that this filter should use, taking the current HTTP request as argument.
    The default implementation delegates to the lookupEntityManagerFactory without arguments, caching the EntityManagerFactory reference once obtained.
    Returns:
    the EntityManagerFactory to use
    See Also:
    lookupEntityManagerFactory()
  - lookupEntityManagerFactory
```
protected 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 EntityManager createEntityManager(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()

Class OpenEntityManagerInViewFilter

Field Summary

Fields inherited from class org.springframework.web.filter.OncePerRequestFilter

Fields inherited from class org.springframework.web.filter.GenericFilterBean

Constructor Summary

Method Summary

Methods inherited from class org.springframework.web.filter.OncePerRequestFilter

Methods inherited from class org.springframework.web.filter.GenericFilterBean

Methods inherited from class java.lang.Object

Field Detail

DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME

Constructor Detail

OpenEntityManagerInViewFilter

Method Detail

setEntityManagerFactoryBeanName

getEntityManagerFactoryBeanName

setPersistenceUnitName

getPersistenceUnitName

shouldNotFilterAsyncDispatch

shouldNotFilterErrorDispatch

doFilterInternal

lookupEntityManagerFactory

lookupEntityManagerFactory

createEntityManager