org.springframework.orm.hibernate3

## Class HibernateAccessor

- java.lang.Object
- - org.springframework.orm.hibernate3.HibernateAccessor

- All Implemented Interfaces:
    Aware, BeanFactoryAware, InitializingBean
  Direct Known Subclasses:
    HibernateInterceptor, HibernateTemplate, OpenSessionInViewInterceptor

      public abstract class HibernateAccessor
      extends Object
      implements InitializingBean, BeanFactoryAware

  Base class for `HibernateTemplate` and `HibernateInterceptor`, defining common properties such as SessionFactory and flushing behavior.

  Not intended to be used directly. See `HibernateTemplate` and `HibernateInterceptor`.

  Since:
    1.2
  Author:
    Juergen Hoeller
  See Also:
    `HibernateTemplate`, `HibernateInterceptor`, `setFlushMode(int)`

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static int` | `FLUSH_ALWAYS` Flushing before every query statement is rarely necessary.
    `static int` | `FLUSH_AUTO` Automatic flushing is the default mode for a Hibernate Session.
    `static 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.
    `static int` | `FLUSH_EAGER` Eager flushing leads to immediate synchronization with the database, even if in a transaction.
    `static int` | `FLUSH_NEVER` Never flush is a good strategy for read-only units of work.
    `protected Log` | `logger` Logger available to subclasses

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `HibernateAccessor()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `afterPropertiesSet()` Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
    `protected 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.
    `protected 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.
    `protected DataAccessException` | `convertJdbcAccessException(SQLException ex)` Convert the given SQLException to an appropriate exception from the `org.springframework.dao` hierarchy.
    `protected void` | `disableFilters(Session session)` Disable the specified filters on the given Session.
    `protected void` | `enableFilters(Session session)` Enable the specified filters on the given Session.
    `protected void` | `flushIfNecessary(Session session, boolean existingTransaction)` Flush the given Hibernate Session if necessary.
    `protected 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.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Field Detail

    - #### FLUSH_NEVER

          public static final int FLUSH_NEVER

      Never flush is a good strategy for read-only units of work. Hibernate will not track and look for changes in this case, avoiding any overhead of modification detection.

      In case of an existing Session, FLUSH_NEVER will turn the flush mode to NEVER for the scope of the current operation, resetting the previous flush mode afterwards.

      See Also:
        `setFlushMode(int)`, Constant Field Values

    - #### FLUSH_AUTO

          public static final int FLUSH_AUTO

      Automatic flushing is the default mode for a Hibernate Session. A session will get flushed on transaction commit, and on certain find operations that might involve already modified instances, but not after each unit of work like with eager flushing.

      In case of an existing Session, FLUSH_AUTO will participate in the existing flush mode, not modifying it for the current operation. This in particular means that this setting will not modify an existing flush mode NEVER, in contrast to FLUSH_EAGER.

      See Also:
        `setFlushMode(int)`, Constant Field Values

    - #### FLUSH_EAGER

          public static final int FLUSH_EAGER

      Eager flushing leads to immediate synchronization with the database, even if in a transaction. This causes inconsistencies to show up and throw a respective exception immediately, and JDBC access code that participates in the same transaction will see the changes as the database is already aware of them then. But the drawbacks are:
      - additional communication roundtrips with the database, instead of a single batch at transaction commit;
      - the fact that an actual database rollback is needed if the Hibernate transaction rolls back (due to already submitted SQL statements).

      In case of an existing Session, FLUSH_EAGER will turn the flush mode to AUTO for the scope of the current operation and issue a flush at the end, resetting the previous flush mode afterwards.

      See Also:
        `setFlushMode(int)`, Constant Field Values

    - #### FLUSH_COMMIT

          public static final 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.

      In case of an existing Session, FLUSH_COMMIT will turn the flush mode to COMMIT for the scope of the current operation, resetting the previous flush mode afterwards. The only exception is an existing flush mode NEVER, which will not be modified through this setting.

      See Also:
        `setFlushMode(int)`, Constant Field Values

    - #### FLUSH_ALWAYS

          public static final int FLUSH_ALWAYS

      Flushing before every query statement is rarely necessary. It is only available for special needs.

      In case of an existing Session, FLUSH_ALWAYS will turn the flush mode to ALWAYS for the scope of the current operation, resetting the previous flush mode afterwards.

      See Also:
        `setFlushMode(int)`, Constant Field Values

    - #### logger

          protected final Log logger

      Logger available to subclasses

  - ### Constructor Detail

    - #### HibernateAccessor

          public HibernateAccessor()

  - ### Method Detail

    - #### setSessionFactory

          public void setSessionFactory(SessionFactory sessionFactory)

      Set the Hibernate SessionFactory that should be used to create Hibernate Sessions.

    - #### getSessionFactory

          public SessionFactory getSessionFactory()

      Return the Hibernate SessionFactory that should be used to create Hibernate Sessions.

    - #### setEntityInterceptorBeanName

          public 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. Will get applied to any new Session created by this transaction manager.

      Requires the bean factory to be known, to be able to resolve the bean name to an interceptor instance on session creation. Typically used for prototype interceptors, i.e. a new interceptor instance per session.

      Can also be used for shared interceptor instances, but it is recommended to set the interceptor reference directly in such a scenario.

      Parameters:
        `entityInterceptorBeanName` - the name of the entity interceptor in the bean factory
      See Also:
        `setBeanFactory(org.springframework.beans.factory.BeanFactory)`, `setEntityInterceptor(org.hibernate.Interceptor)`

    - #### setEntityInterceptor

          public 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. Will get applied to any new Session created by this object.

      Such an interceptor can either be set at the SessionFactory level, i.e. on LocalSessionFactoryBean, or at the Session level, i.e. on HibernateTemplate, HibernateInterceptor, and HibernateTransactionManager. It's preferable to set it on LocalSessionFactoryBean or HibernateTransactionManager to avoid repeated configuration and guarantee consistent behavior in transactions.

      See Also:
        `setEntityInterceptorBeanName(java.lang.String)`, `LocalSessionFactoryBean.setEntityInterceptor(org.hibernate.Interceptor)`, `HibernateTransactionManager.setEntityInterceptor(org.hibernate.Interceptor)`

    - #### getEntityInterceptor

          public Interceptor getEntityInterceptor()
                                           throws IllegalStateException,
                                                  BeansException

      Return the current Hibernate entity interceptor, or `null` if none. Resolves an entity interceptor bean name via the bean factory, if necessary.
      Throws:
        `IllegalStateException` - if bean name specified but no bean factory set
        `BeansException` - if bean name resolution via the bean factory failed
      See Also:
        `setEntityInterceptor(org.hibernate.Interceptor)`, `setEntityInterceptorBeanName(java.lang.String)`, `setBeanFactory(org.springframework.beans.factory.BeanFactory)`

    - #### setJdbcExceptionTranslator

          public void setJdbcExceptionTranslator(SQLExceptionTranslator jdbcExceptionTranslator)

      Set the JDBC exception translator for this instance.

      Applied to any SQLException root cause of a Hibernate JDBCException, overriding Hibernate's default SQLException translation (which is based on Hibernate's Dialect for a specific target database).

      Parameters:
        `jdbcExceptionTranslator` - the exception translator
      See Also:
        `SQLException`, `JDBCException`, `SQLErrorCodeSQLExceptionTranslator`, `SQLStateSQLExceptionTranslator`

    - #### getJdbcExceptionTranslator

          public SQLExceptionTranslator getJdbcExceptionTranslator()

      Return the JDBC exception translator for this instance, if any.

    - #### setFlushModeName

          public void setFlushModeName(String constantName)

      Set the flush behavior by the name of the respective constant in this class, e.g. "FLUSH_AUTO". Default is "FLUSH_AUTO".
      Parameters:
        `constantName` - name of the constant
      See Also:
        `setFlushMode(int)`, `FLUSH_AUTO`

    - #### setFlushMode

          public void setFlushMode(int flushMode)

      Set the flush behavior to one of the constants in this class. Default is FLUSH_AUTO.
      See Also:
        `setFlushModeName(java.lang.String)`, `FLUSH_AUTO`

    - #### getFlushMode

          public int getFlushMode()

      Return if a flush should be forced after executing the callback code.

    - #### setFilterName

          public void setFilterName(String filter)

      Set the name of a Hibernate filter to be activated for all Sessions that this accessor works with.

      This filter will be enabled at the beginning of each operation and correspondingly disabled at the end of the operation. This will work for newly opened Sessions as well as for existing Sessions (for example, within a transaction).

      See Also:
        `enableFilters(org.hibernate.Session)`, `Session.enableFilter(String)`, `LocalSessionFactoryBean.setFilterDefinitions(org.hibernate.engine.FilterDefinition...)`

    - #### setFilterNames

          public void setFilterNames(String... filterNames)

      Set one or more names of Hibernate filters to be activated for all Sessions that this accessor works with.

      Each of those filters will be enabled at the beginning of each operation and correspondingly disabled at the end of the operation. This will work for newly opened Sessions as well as for existing Sessions (for example, within a transaction).

      See Also:
        `enableFilters(org.hibernate.Session)`, `Session.enableFilter(String)`, `LocalSessionFactoryBean.setFilterDefinitions(org.hibernate.engine.FilterDefinition...)`

    - #### getFilterNames

          public String[] getFilterNames()

      Return the names of Hibernate filters to be activated, if any.

    - #### setBeanFactory

          public void setBeanFactory(BeanFactory beanFactory)

      The bean factory just needs to be known for resolving entity interceptor bean names. It does not need to be set for any other mode of operation.
      Specified by:
        `setBeanFactory` in interface `BeanFactoryAware`
      Parameters:
        `beanFactory` - owning BeanFactory (never `null`). The bean can immediately call methods on the factory.
      See Also:
        `setEntityInterceptorBeanName(java.lang.String)`

    - #### afterPropertiesSet

          public void afterPropertiesSet()

      Description copied from interface: `InitializingBean`
      Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).

      This method allows the bean instance to perform initialization only possible when all bean properties have been set and to throw an exception in the event of misconfiguration.

      Specified by:
        `afterPropertiesSet` in interface `InitializingBean`

    - #### applyFlushMode

          protected FlushMode applyFlushMode(Session session,
                                 boolean existingTransaction)

      Apply the flush mode that's been specified for this accessor to the given Session.
      Parameters:
        `session` - the current Hibernate Session
        `existingTransaction` - if executing within an existing transaction
      Returns:
        the previous flush mode to restore after the operation, or `null` if none
      See Also:
        `setFlushMode(int)`, `Session.setFlushMode(org.hibernate.FlushMode)`

    - #### flushIfNecessary

          protected void flushIfNecessary(Session session,
                              boolean existingTransaction)
                                   throws HibernateException

      Flush the given Hibernate Session if necessary.
      Parameters:
        `session` - the current Hibernate Session
        `existingTransaction` - if executing within an existing transaction
      Throws:
        `HibernateException` - in case of Hibernate flushing errors

    - #### convertHibernateAccessException

          public DataAccessException convertHibernateAccessException(HibernateException ex)

      Convert the given HibernateException to an appropriate exception from the `org.springframework.dao` hierarchy.

      Will automatically apply a specified SQLExceptionTranslator to a Hibernate JDBCException, else rely on Hibernate's default translation.

      Parameters:
        `ex` - HibernateException that occured
      Returns:
        a corresponding DataAccessException
      See Also:
        `SessionFactoryUtils.convertHibernateAccessException(org.hibernate.HibernateException)`, `setJdbcExceptionTranslator(org.springframework.jdbc.support.SQLExceptionTranslator)`

    - #### convertJdbcAccessException

          protected 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.
      Parameters:
        `ex` - Hibernate JDBCException that occured
        `translator` - the SQLExceptionTranslator to use
      Returns:
        a corresponding DataAccessException

    - #### convertJdbcAccessException

          protected DataAccessException convertJdbcAccessException(SQLException ex)

      Convert the given SQLException to an appropriate exception from the `org.springframework.dao` hierarchy. Can be overridden in subclasses.

      Note that a direct SQLException can just occur when callback code performs direct JDBC access via `Session.connection()`.

      Parameters:
        `ex` - the SQLException
      Returns:
        the corresponding DataAccessException instance
      See Also:
        `setJdbcExceptionTranslator(org.springframework.jdbc.support.SQLExceptionTranslator)`

    - #### getDefaultJdbcExceptionTranslator

          protected SQLExceptionTranslator getDefaultJdbcExceptionTranslator()

      Obtain a default SQLExceptionTranslator, lazily creating it if necessary.

      Creates a default `SQLErrorCodeSQLExceptionTranslator` for the SessionFactory's underlying DataSource.

    - #### enableFilters

          protected void enableFilters(Session session)

      Enable the specified filters on the given Session.
      Parameters:
        `session` - the current Hibernate Session
      See Also:
        `setFilterNames(java.lang.String...)`, `Session.enableFilter(String)`

    - #### disableFilters

          protected void disableFilters(Session session)

      Disable the specified filters on the given Session.
      Parameters:
        `session` - the current Hibernate Session
      See Also:
        `setFilterNames(java.lang.String...)`, `Session.disableFilter(String)`