org.springframework.orm.toplink.UnitOfWorkCallback 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.toplink;
import oracle.toplink.exceptions.TopLinkException;
import oracle.toplink.sessions.Session;
import oracle.toplink.sessions.UnitOfWork;
/**
* Convenient abstract implementation of the TopLinkCallback interface,
* exposing a UnitOfWork to perform write operations on.
*
* The exposed UnitOfWork will either be be the active UnitOfWork of
* the current transaction, if any, or a temporarily acquired UnitOfWork
* that will be committed at the end of the operation.
*
* @author Juergen Hoeller
* @since 1.2
* @see #doInUnitOfWork(oracle.toplink.sessions.UnitOfWork)
* @see oracle.toplink.sessions.Session#getActiveUnitOfWork()
*/
public abstract class UnitOfWorkCallback implements TopLinkCallback {
/**
* Determines the UnitOfWork to work on (either the active UnitOfWork or a
* temporarily acquired UnitOfWork) and delegates to doInUnitOfWork.
* @see #doInUnitOfWork(oracle.toplink.sessions.UnitOfWork)
*/
public final Object doInTopLink(Session session) throws TopLinkException {
// Fetch active UnitOfWork or acquire temporary UnitOfWork.
UnitOfWork unitOfWork = session.getActiveUnitOfWork();
boolean newUnitOfWork = false;
if (unitOfWork == null) {
unitOfWork = session.acquireUnitOfWork();
newUnitOfWork = true;
}
// Perform callback operation, committing the UnitOfWork unless
// it is the active UnitOfWork of an externally managed transaction.
try {
Object result = doInUnitOfWork(unitOfWork);
if (newUnitOfWork) {
unitOfWork.commit();
}
return result;
}
finally {
if (newUnitOfWork) {
unitOfWork.release();
}
}
}
/**
* Called with a UnitOfWork to work on, either the active UnitOfWork or a
* temporarily acquired UnitOfWork (as determined by the transaction status).
* @param unitOfWork the TopLink UnitOfWork to perform write operations on
* @return a result object, or null if none
* @throws TopLinkException in case of TopLink errors
*/
protected abstract Object doInUnitOfWork(UnitOfWork unitOfWork) throws TopLinkException;
}