OpenSessionInViewInterceptor

Class Overview

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 or JtaTransactionManager 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. It inherits common Hibernate configuration properties from HibernateAccessor, to be configured in a bean definition.

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.

Alternatively, turn this interceptor into deferred close mode, by specifying "singleSession"="false": It will not use a single session per request then, but rather let each data access operation or transaction use its own session (as would be the case without Open Session in View). Each of those sessions will be registered for deferred close though, which will actually be processed at request completion.

A single session per request allows for the most efficient first-level caching, but can cause side effects, for example on saveOrUpdate or when continuing after a rolled-back transaction. The deferred close strategy is as safe as no Open Session in View in that respect, while still allowing for lazy loading in views (but not providing a first-level cache for the entire request).

Summary

[Expand] Inherited Constants

From class org.springframework.orm.hibernate3.HibernateAccessor int FLUSH_ALWAYS Flushing before every query statement is rarely necessary. int FLUSH_AUTO Automatic flushing is the default mode for a Hibernate Session. int FLUSH_COMMIT Flushing at commit only is intended for units of work where no intermediate flushing is desired, not even for find operations that might involve already modified instances. int FLUSH_EAGER Eager flushing leads to immediate synchronization with the database, even if in a transaction. int FLUSH_NEVER Never flush is a good strategy for read-only units of work.

[Expand] Inherited Fields
From class org.springframework.orm.hibernate3.HibernateAccessor protected final Log logger Logger available to subclasses

[Expand] Inherited Methods
From class org.springframework.orm.hibernate3.HibernateAccessor void afterPropertiesSet() Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware). FlushMode applyFlushMode(Session session, boolean existingTransaction) Apply the flush mode that's been specified for this accessor to the given Session. DataAccessException convertHibernateAccessException(HibernateException ex) Convert the given HibernateException to an appropriate exception from the org.springframework.dao hierarchy. DataAccessException convertJdbcAccessException(SQLException ex) Convert the given SQLException to an appropriate exception from the org.springframework.dao hierarchy. DataAccessException convertJdbcAccessException(JDBCException ex, SQLExceptionTranslator translator) Convert the given Hibernate JDBCException to an appropriate exception from the org.springframework.dao hierarchy, using the given SQLExceptionTranslator. void disableFilters(Session session) Disable the specified filters on the given Session. void enableFilters(Session session) Enable the specified filters on the given Session. void flushIfNecessary(Session session, boolean existingTransaction) Flush the given Hibernate Session if necessary. synchronized SQLExceptionTranslator getDefaultJdbcExceptionTranslator() Obtain a default SQLExceptionTranslator, lazily creating it if necessary. Interceptor getEntityInterceptor() Return the current Hibernate entity interceptor, or null if none. String[] getFilterNames() Return the names of Hibernate filters to be activated, if any. int getFlushMode() Return if a flush should be forced after executing the callback code. SQLExceptionTranslator getJdbcExceptionTranslator() Return the JDBC exception translator for this instance, if any. SessionFactory getSessionFactory() Return the Hibernate SessionFactory that should be used to create Hibernate Sessions. void setBeanFactory(BeanFactory beanFactory) The bean factory just needs to be known for resolving entity interceptor bean names. void setEntityInterceptor(Interceptor entityInterceptor) Set a Hibernate entity interceptor that allows to inspect and change property values before writing to and reading from the database. void setEntityInterceptorBeanName(String entityInterceptorBeanName) Set the bean name of a Hibernate entity interceptor that allows to inspect and change property values before writing to and reading from the database. void setFilterName(String filter) Set the name of a Hibernate filter to be activated for all Sessions that this accessor works with. void setFilterNames(String[] filterNames) Set one or more names of Hibernate filters to be activated for all Sessions that this accessor works with. void setFlushMode(int flushMode) Set the flush behavior to one of the constants in this class. void setFlushModeName(String constantName) Set the flush behavior by the name of the respective constant in this class, e.g. void setJdbcExceptionTranslator(SQLExceptionTranslator jdbcExceptionTranslator) Set the JDBC exception translator for this instance. void setSessionFactory(SessionFactory sessionFactory) Set the Hibernate SessionFactory that should be used to create Hibernate Sessions.
From class java.lang.Object Object clone() boolean equals(Object arg0) void finalize() final Class<?> getClass() int hashCode() final void notify() final void notifyAll() String toString() final void wait() final void wait(long arg0, int arg1) final void wait(long arg0)
From interface org.springframework.beans.factory.BeanFactoryAware abstract void setBeanFactory(BeanFactory beanFactory) Callback that supplies the owning factory to a bean instance.
From interface org.springframework.beans.factory.InitializingBean abstract void afterPropertiesSet() Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
From interface org.springframework.web.context.request.WebRequestInterceptor abstract void afterCompletion(WebRequest request, Exception ex) Callback after completion of request processing, that is, after rendering the view. abstract void postHandle(WebRequest request, ModelMap model) Intercept the execution of a request handler after its successful invocation, right before view rendering (if any). abstract void preHandle(WebRequest request) Intercept the execution of a request handler before its invocation.