/*
* Copyright 2002-2008 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.orm.hibernate3.support;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.dao.support.DaoSupport;
import org.springframework.orm.hibernate3.HibernateTemplate;
import org.springframework.orm.hibernate3.SessionFactoryUtils;
/**
* Convenient super class for Hibernate-based data access objects.
*
* <p>Requires a {@link org.hibernate.SessionFactory} to be set, providing a
* {@link org.springframework.orm.hibernate3.HibernateTemplate} based on it to
* subclasses through the {@link #getHibernateTemplate()} method.
* Can alternatively be initialized directly with a HibernateTemplate,
* in order to reuse the latter's settings such as the SessionFactory,
* exception translator, flush mode, etc.
*
* <p>This base class is mainly intended for HibernateTemplate usage but can
* also be used when working with a Hibernate Session directly, for example
* when relying on transactional Sessions. Convenience {@link #getSession}
* and {@link #releaseSession} methods are provided for that usage style.
*
* <p>This class will create its own HibernateTemplate instance if a SessionFactory
* is passed in. The "allowCreate" flag on that HibernateTemplate will be "true"
* by default. A custom HibernateTemplate instance can be used through overriding
* {@link #createHibernateTemplate}.
*
* @author Juergen Hoeller
* @since 1.2
* @see #setSessionFactory
* @see #getHibernateTemplate
* @see org.springframework.orm.hibernate3.HibernateTemplate
*/
public abstract class HibernateDaoSupport extends DaoSupport {
private HibernateTemplate hibernateTemplate;
/**
* Set the Hibernate SessionFactory to be used by this DAO.
* Will automatically create a HibernateTemplate for the given SessionFactory.
* @see #createHibernateTemplate
* @see #setHibernateTemplate
*/
public final void setSessionFactory(SessionFactory sessionFactory) {
if (this.hibernateTemplate == null || sessionFactory != this.hibernateTemplate.getSessionFactory()) {
this.hibernateTemplate = createHibernateTemplate(sessionFactory);
}
}
/**
* Create a HibernateTemplate for the given SessionFactory.
* Only invoked if populating the DAO with a SessionFactory reference!
* <p>Can be overridden in subclasses to provide a HibernateTemplate instance
* with different configuration, or a custom HibernateTemplate subclass.
* @param sessionFactory the Hibernate SessionFactory to create a HibernateTemplate for
* @return the new HibernateTemplate instance
* @see #setSessionFactory
*/
protected HibernateTemplate createHibernateTemplate(SessionFactory sessionFactory) {
return new HibernateTemplate(sessionFactory);
}
/**
* Return the Hibernate SessionFactory used by this DAO.
*/
public final SessionFactory getSessionFactory() {
return (this.hibernateTemplate != null ? this.hibernateTemplate.getSessionFactory() : null);
}
/**
* Set the HibernateTemplate for this DAO explicitly,
* as an alternative to specifying a SessionFactory.
* @see #setSessionFactory
*/
public final void setHibernateTemplate(HibernateTemplate hibernateTemplate) {
this.hibernateTemplate = hibernateTemplate;
}
/**
* Return the HibernateTemplate for this DAO,
* pre-initialized with the SessionFactory or set explicitly.
* <p><b>Note: The returned HibernateTemplate is a shared instance.</b>
* You may introspect its configuration, but not modify the configuration
* (other than from within an {@link #initDao} implementation).
* Consider creating a custom HibernateTemplate instance via
* <code>new HibernateTemplate(getSessionFactory())</code>, in which
* case you're allowed to customize the settings on the resulting instance.
*/
public final HibernateTemplate getHibernateTemplate() {
return this.hibernateTemplate;
}
@Override
protected final void checkDaoConfig() {
if (this.hibernateTemplate == null) {
throw new IllegalArgumentException("'sessionFactory' or 'hibernateTemplate' is required");
}
}
/**
* Obtain a Hibernate Session, either from the current transaction or
* a new one. The latter is only allowed if the
* {@link org.springframework.orm.hibernate3.HibernateTemplate#setAllowCreate "allowCreate"}
* setting of this bean's {@link #setHibernateTemplate HibernateTemplate} is "true".
* <p><b>Note that this is not meant to be invoked from HibernateTemplate code
* but rather just in plain Hibernate code.</b> Either rely on a thread-bound
* Session or use it in combination with {@link #releaseSession}.
* <p>In general, it is recommended to use HibernateTemplate, either with
* the provided convenience operations or with a custom HibernateCallback
* that provides you with a Session to work on. HibernateTemplate will care
* for all resource management and for proper exception conversion.
* @return the Hibernate Session
* @throws DataAccessResourceFailureException if the Session couldn't be created
* @throws IllegalStateException if no thread-bound Session found and allowCreate=false
* @see org.springframework.orm.hibernate3.SessionFactoryUtils#getSession(SessionFactory, boolean)
*/
protected final Session getSession()
throws DataAccessResourceFailureException, IllegalStateException {
return getSession(this.hibernateTemplate.isAllowCreate());
}
/**
* Obtain a Hibernate Session, either from the current transaction or
* a new one. The latter is only allowed if "allowCreate" is true.
* <p><b>Note that this is not meant to be invoked from HibernateTemplate code
* but rather just in plain Hibernate code.</b> Either rely on a thread-bound
* Session or use it in combination with {@link #releaseSession}.
* <p>In general, it is recommended to use
* {@link #getHibernateTemplate() HibernateTemplate}, either with
* the provided convenience operations or with a custom
* {@link org.springframework.orm.hibernate3.HibernateCallback} that
* provides you with a Session to work on. HibernateTemplate will care
* for all resource management and for proper exception conversion.
* @param allowCreate if a non-transactional Session should be created when no
* transactional Session can be found for the current thread
* @return the Hibernate Session
* @throws DataAccessResourceFailureException if the Session couldn't be created
* @throws IllegalStateException if no thread-bound Session found and allowCreate=false
* @see org.springframework.orm.hibernate3.SessionFactoryUtils#getSession(SessionFactory, boolean)
*/
protected final Session getSession(boolean allowCreate)
throws DataAccessResourceFailureException, IllegalStateException {
return (!allowCreate ?
SessionFactoryUtils.getSession(getSessionFactory(), false) :
SessionFactoryUtils.getSession(
getSessionFactory(),
this.hibernateTemplate.getEntityInterceptor(),
this.hibernateTemplate.getJdbcExceptionTranslator()));
}
/**
* Convert the given HibernateException to an appropriate exception from the
* <code>org.springframework.dao</code> hierarchy. Will automatically detect
* wrapped SQLExceptions and convert them accordingly.
* <p>Delegates to the
* {@link org.springframework.orm.hibernate3.HibernateTemplate#convertHibernateAccessException}
* method of this DAO's HibernateTemplate.
* <p>Typically used in plain Hibernate code, in combination with
* {@link #getSession} and {@link #releaseSession}.
* @param ex HibernateException that occurred
* @return the corresponding DataAccessException instance
* @see org.springframework.orm.hibernate3.SessionFactoryUtils#convertHibernateAccessException
*/
protected final DataAccessException convertHibernateAccessException(HibernateException ex) {
return this.hibernateTemplate.convertHibernateAccessException(ex);
}
/**
* Close the given Hibernate Session, created via this DAO's SessionFactory,
* if it isn't bound to the thread (i.e. isn't a transactional Session).
* <p>Typically used in plain Hibernate code, in combination with
* {@link #getSession} and {@link #convertHibernateAccessException}.
* @param session the Session to close
* @see org.springframework.orm.hibernate3.SessionFactoryUtils#releaseSession
*/
protected final void releaseSession(Session session) {
SessionFactoryUtils.releaseSession(session, getSessionFactory());
}
}
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