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

所有已实现的接口:
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).
从以下版本开始:
2.0
作者:
Juergen Hoeller
另请参阅:
OpenEntityManagerInViewInterceptor, JpaTransactionManager, SharedEntityManagerCreator, TransactionSynchronizationManager

字段概要
字段
修饰符和类型字段说明
static String DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME
Default EntityManagerFactory bean name: "entityManagerFactory".
- 从类继承的字段 org.springframework.web.filter.OncePerRequestFilter
  ALREADY_FILTERED_SUFFIX
- 从类继承的字段 org.springframework.web.filter.GenericFilterBean
  logger

构造器概要
构造器
构造器说明
OpenEntityManagerInViewFilter()

方法概要

所有方法实例方法具体方法
修饰符和类型	方法	说明
`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.

从类继承的方法 org.springframework.web.filter.OncePerRequestFilter
doFilter, getAlreadyFilteredAttributeName, isAsyncDispatch, isAsyncStarted, shouldNotFilter

从类继承的方法 org.springframework.web.filter.GenericFilterBean
addRequiredProperty, afterPropertiesSet, createEnvironment, destroy, getEnvironment, getFilterConfig, getFilterName, getServletContext, init, initBeanWrapper, initFilterBean, setBeanName, setEnvironment, setServletContext

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 字段详细资料
  - 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.
    另请参阅:
    setEntityManagerFactoryBeanName(java.lang.String), setPersistenceUnitName(java.lang.String), 常量字段值
- 构造器详细资料
  - OpenEntityManagerInViewFilter
```
public OpenEntityManagerInViewFilter()
```
- 方法详细资料
  - 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.
    另请参阅:
    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.
    另请参阅:
    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.
    覆盖:
    shouldNotFilterAsyncDispatch 在类中 OncePerRequestFilter
  - shouldNotFilterErrorDispatch
```
protected boolean shouldNotFilterErrorDispatch()
```
    Returns "false" so that the filter may provide an EntityManager to each error dispatches.
    覆盖:
    shouldNotFilterErrorDispatch 在类中 OncePerRequestFilter
  - doFilterInternal
```
protected void doFilterInternal(HttpServletRequest request,
                                HttpServletResponse response,
                                FilterChain filterChain)
                         throws ServletException,
                                IOException
```
    从类复制的说明: 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.
    指定者:
    doFilterInternal 在类中 OncePerRequestFilter
    抛出:
    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.
    返回:
    the EntityManagerFactory to use
    另请参阅:
    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.
    返回:
    the EntityManagerFactory to use
    另请参阅:
    getEntityManagerFactoryBeanName()
  - createEntityManager
```
protected EntityManager createEntityManager(EntityManagerFactory emf)
```
    Create a JPA EntityManager to be bound to a request.
    Can be overridden in subclasses.
    参数:
    emf - the EntityManagerFactory to use
    另请参阅:
    EntityManagerFactory.createEntityManager()

类 OpenEntityManagerInViewFilter

字段概要

从类继承的字段 org.springframework.web.filter.OncePerRequestFilter

从类继承的字段 org.springframework.web.filter.GenericFilterBean

构造器概要

方法概要

从类继承的方法 org.springframework.web.filter.OncePerRequestFilter

从类继承的方法 org.springframework.web.filter.GenericFilterBean

从类继承的方法 java.lang.Object

字段详细资料

DEFAULT_ENTITY_MANAGER_FACTORY_BEAN_NAME

构造器详细资料

OpenEntityManagerInViewFilter

方法详细资料

setEntityManagerFactoryBeanName

getEntityManagerFactoryBeanName

setPersistenceUnitName

getPersistenceUnitName

shouldNotFilterAsyncDispatch

shouldNotFilterErrorDispatch

doFilterInternal

lookupEntityManagerFactory

lookupEntityManagerFactory

createEntityManager