org.springframework.orm.hibernate.HibernateCallback Maven / Gradle / Ivy
/*
* Copyright 2002-2005 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.hibernate;
import java.sql.SQLException;
import net.sf.hibernate.HibernateException;
import net.sf.hibernate.Session;
/**
* Callback interface for Hibernate code. To be used with HibernateTemplate's execute
* method, assumably often as anonymous classes within a method implementation.
* The typical implementation will call Session.load/find/save/update to perform
* some operations on persistent objects. It can also perform direct JDBC operations
* via Hibernate's Session.connection() method, returning the active JDBC connection.
*
* Note that Hibernate works on unmodified plain Java objects, performing dirty
* detection via copies made at load time. Returned objects can thus be used outside
* of an active Hibernate Session without any hassle, e.g. for display in a web GUI.
* Reassociating such instances with a new Session, e.g. for updates when coming
* back from the GUI, is straightforward, as the instance has kept its identity.
* You should care to reassociate them as early as possible though, to avoid having
* already loaded a version from the database in the same Session.
*
* @author Juergen Hoeller
* @since 02.05.2003
* @see HibernateTemplate
*/
public interface HibernateCallback {
/**
* Gets called by HibernateTemplate.execute
with an active
* Hibernate Session. Does not need to care about activating or closing
* the Session, or handling transactions.
*
*
If called without a thread-bound Hibernate transaction (initiated
* by HibernateTransactionManager), the code will simply get executed on the
* underlying JDBC connection with its transactional semantics. If Hibernate
* is configured to use a JTA-aware DataSource, the JDBC connection and thus
* the callback code will be transactional if a JTA transaction is active.
*
*
Allows for returning a result object created within the callback, i.e.
* a domain object or a collection of domain objects. Note that there's
* special support for single step actions: see HibernateTemplate.find etc.
* A thrown RuntimeException is treated as application exception, it gets
* propagated to the caller of the template.
*
* @param session active Hibernate session
* @return a result object, or null
if none
* @throws HibernateException in case of Hibernate errors
* @throws SQLException in case of errors on direct JDBC access
* @see HibernateTemplate#execute
* @see HibernateTransactionManager
*/
Object doInHibernate(Session session) throws HibernateException, SQLException;
}