/*
* Copyright 2002-2006 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.jdo;
import javax.jdo.JDOException;
import javax.jdo.PersistenceManager;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.springframework.transaction.support.TransactionSynchronizationManager;
/**
* This interceptor binds a new JDO PersistenceManager to the thread before a method
* call, closing and removing it afterwards in case of any method outcome.
* If there already is a pre-bound PersistenceManager (e.g. from JdoTransactionManager,
* or from a surrounding JDO-intercepted method), the interceptor simply participates in it.
*
* <p>Application code must retrieve a JDO PersistenceManager via the
* <code>PersistenceManagerFactoryUtils.getPersistenceManager</code> method,
* to be able to detect a thread-bound PersistenceManager. It is preferable to use
* <code>getPersistenceManager</code> with allowCreate=false, if the code relies on
* the interceptor to provide proper PersistenceManager handling. Typically, the code
* will look like as follows:
*
* <pre>
* public void doSomeDataAccessAction() {
* PersistenceManager pm = PersistenceManagerFactoryUtils.getPersistenceManager(this.pmf, false);
* ...
* }</pre>
*
* <p>Note that this interceptor automatically translates JDOExceptions, via
* delegating to the <code>PersistenceManagerFactoryUtils.convertJdoAccessException</code>
* method that converts them to exceptions that are compatible with the
* <code>org.springframework.dao</code> exception hierarchy (like JdoTemplate does).
* This can be turned off if the raw exceptions are preferred.
*
* <p>This class can be considered a declarative alternative to JdoTemplate's
* callback approach. The advantages are:
* <ul>
* <li>no anonymous classes necessary for callback implementations;
* <li>the possibility to throw any application exceptions from within data access code.
* </ul>
*
* <p>The drawback is the dependency on interceptor configuration. However, note
* that this interceptor is usually <i>not</i> necessary in scenarios where the
* data access code always executes within transactions. A transaction will always
* have a thread-bound PersistenceManager in the first place, so adding this interceptor
* to the configuration just adds value when fine-tuning PersistenceManager settings
* like the flush mode - or when relying on exception translation.
*
* @author Juergen Hoeller
* @since 13.06.2003
* @see PersistenceManagerFactoryUtils#getPersistenceManager
* @see JdoTransactionManager
* @see JdoTemplate
*/
public class JdoInterceptor extends JdoAccessor implements MethodInterceptor {
private boolean exceptionConversionEnabled = true;
/**
* Set whether to convert any JDOException raised to a Spring DataAccessException,
* compatible with the <code>org.springframework.dao</code> exception hierarchy.
* <p>Default is "true". Turn this flag off to let the caller receive raw exceptions
* as-is, without any wrapping.
* @see org.springframework.dao.DataAccessException
*/
public void setExceptionConversionEnabled(boolean exceptionConversionEnabled) {
this.exceptionConversionEnabled = exceptionConversionEnabled;
}
public Object invoke(MethodInvocation methodInvocation) throws Throwable {
boolean existingTransaction = false;
PersistenceManager pm = PersistenceManagerFactoryUtils.getPersistenceManager(getPersistenceManagerFactory(), true);
if (TransactionSynchronizationManager.hasResource(getPersistenceManagerFactory())) {
logger.debug("Found thread-bound PersistenceManager for JDO interceptor");
existingTransaction = true;
}
else {
logger.debug("Using new PersistenceManager for JDO interceptor");
TransactionSynchronizationManager.bindResource(getPersistenceManagerFactory(), new PersistenceManagerHolder(pm));
}
try {
Object retVal = methodInvocation.proceed();
flushIfNecessary(pm, existingTransaction);
return retVal;
}
catch (JDOException ex) {
if (this.exceptionConversionEnabled) {
throw convertJdoAccessException(ex);
}
else {
throw ex;
}
}
finally {
if (existingTransaction) {
logger.debug("Not closing pre-bound JDO PersistenceManager after interceptor");
}
else {
TransactionSynchronizationManager.unbindResource(getPersistenceManagerFactory());
PersistenceManagerFactoryUtils.releasePersistenceManager(pm, getPersistenceManagerFactory());
}
}
}
}
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