/*
* Copyright 2002-2010 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.jpa;
import java.util.Map;
import javax.persistence.EntityExistsException;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityNotFoundException;
import javax.persistence.NoResultException;
import javax.persistence.NonUniqueResultException;
import javax.persistence.OptimisticLockException;
import javax.persistence.PersistenceException;
import javax.persistence.Query;
import javax.persistence.TransactionRequiredException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.beans.factory.ListableBeanFactory;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.core.Ordered;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.dao.EmptyResultDataAccessException;
import org.springframework.dao.IncorrectResultSizeDataAccessException;
import org.springframework.dao.InvalidDataAccessApiUsageException;
import org.springframework.jdbc.datasource.DataSourceUtils;
import org.springframework.transaction.support.ResourceHolderSynchronization;
import org.springframework.transaction.support.TransactionSynchronizationManager;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
/**
* Helper class featuring methods for JPA EntityManager handling,
* allowing for reuse of EntityManager instances within transactions.
* Also provides support for exception translation.
*
* <p>Mainly intended for internal use within the framework.
*
* @author Juergen Hoeller
* @since 2.0
*/
public abstract class EntityManagerFactoryUtils {
/**
* Order value for TransactionSynchronization objects that clean up JPA
* EntityManagers. Return DataSourceUtils.CONNECTION_SYNCHRONIZATION_ORDER - 100
* to execute EntityManager cleanup before JDBC Connection cleanup, if any.
* @see org.springframework.jdbc.datasource.DataSourceUtils#CONNECTION_SYNCHRONIZATION_ORDER
*/
public static final int ENTITY_MANAGER_SYNCHRONIZATION_ORDER =
DataSourceUtils.CONNECTION_SYNCHRONIZATION_ORDER - 100;
private static final Log logger = LogFactory.getLog(EntityManagerFactoryUtils.class);
/**
* Find an EntityManagerFactory with the given name in the given
* Spring application context (represented as ListableBeanFactory).
* <p>The specified unit name will be matched against the configured
* peristence unit, provided that a discovered EntityManagerFactory
* implements the {@link EntityManagerFactoryInfo} interface. If not,
* the persistence unit name will be matched against the Spring bean name,
* assuming that the EntityManagerFactory bean names follow that convention.
* @param beanFactory the ListableBeanFactory to search
* @param unitName the name of the persistence unit (never empty)
* @return the EntityManagerFactory
* @throws NoSuchBeanDefinitionException if there is no such EntityManagerFactory in the context
* @see EntityManagerFactoryInfo#getPersistenceUnitName()
*/
public static EntityManagerFactory findEntityManagerFactory(
ListableBeanFactory beanFactory, String unitName) throws NoSuchBeanDefinitionException {
Assert.notNull(beanFactory, "ListableBeanFactory must not be null");
Assert.hasLength(unitName, "Unit name must not be empty");
// See whether we can find an EntityManagerFactory with matching persistence unit name.
String[] candidateNames =
BeanFactoryUtils.beanNamesForTypeIncludingAncestors(beanFactory, EntityManagerFactory.class);
for (String candidateName : candidateNames) {
EntityManagerFactory emf = (EntityManagerFactory) beanFactory.getBean(candidateName);
if (emf instanceof EntityManagerFactoryInfo) {
if (unitName.equals(((EntityManagerFactoryInfo) emf).getPersistenceUnitName())) {
return emf;
}
}
}
// No matching persistence unit found - simply take the EntityManagerFactory
// with the persistence unit name as bean name (by convention).
return beanFactory.getBean(unitName, EntityManagerFactory.class);
}
/**
* Obtain a JPA EntityManager from the given factory. Is aware of a
* corresponding EntityManager bound to the current thread,
* for example when using JpaTransactionManager.
* <p>Note: Will return <code>null</code> if no thread-bound EntityManager found!
* @param emf EntityManagerFactory to create the EntityManager with
* @return the EntityManager, or <code>null</code> if none found
* @throws DataAccessResourceFailureException if the EntityManager couldn't be obtained
* @see JpaTransactionManager
*/
public static EntityManager getTransactionalEntityManager(EntityManagerFactory emf)
throws DataAccessResourceFailureException {
return getTransactionalEntityManager(emf, null);
}
/**
* Obtain a JPA EntityManager from the given factory. Is aware of a
* corresponding EntityManager bound to the current thread,
* for example when using JpaTransactionManager.
* <p>Note: Will return <code>null</code> if no thread-bound EntityManager found!
* @param emf EntityManagerFactory to create the EntityManager with
* @param properties the properties to be passed into the <code>createEntityManager</code>
* call (may be <code>null</code>)
* @return the EntityManager, or <code>null</code> if none found
* @throws DataAccessResourceFailureException if the EntityManager couldn't be obtained
* @see JpaTransactionManager
*/
public static EntityManager getTransactionalEntityManager(EntityManagerFactory emf, Map properties)
throws DataAccessResourceFailureException {
try {
return doGetTransactionalEntityManager(emf, properties);
}
catch (PersistenceException ex) {
throw new DataAccessResourceFailureException("Could not obtain JPA EntityManager", ex);
}
}
/**
* Obtain a JPA EntityManager from the given factory. Is aware of a
* corresponding EntityManager bound to the current thread,
* for example when using JpaTransactionManager.
* <p>Same as <code>getEntityManager</code>, but throwing the original PersistenceException.
* @param emf EntityManagerFactory to create the EntityManager with
* @param properties the properties to be passed into the <code>createEntityManager</code>
* call (may be <code>null</code>)
* @return the EntityManager, or <code>null</code> if none found
* @throws javax.persistence.PersistenceException if the EntityManager couldn't be created
* @see #getTransactionalEntityManager(javax.persistence.EntityManagerFactory)
* @see JpaTransactionManager
*/
public static EntityManager doGetTransactionalEntityManager(
EntityManagerFactory emf, Map properties) throws PersistenceException {
Assert.notNull(emf, "No EntityManagerFactory specified");
EntityManagerHolder emHolder =
(EntityManagerHolder) TransactionSynchronizationManager.getResource(emf);
if (emHolder != null) {
if (!emHolder.isSynchronizedWithTransaction() &&
TransactionSynchronizationManager.isSynchronizationActive()) {
// Try to explicitly synchronize the EntityManager itself
// with an ongoing JTA transaction, if any.
try {
emHolder.getEntityManager().joinTransaction();
}
catch (TransactionRequiredException ex) {
logger.debug("Could not join JTA transaction because none was active", ex);
}
Object transactionData = prepareTransaction(emHolder.getEntityManager(), emf);
TransactionSynchronizationManager.registerSynchronization(
new EntityManagerSynchronization(emHolder, emf, transactionData, false));
emHolder.setSynchronizedWithTransaction(true);
}
return emHolder.getEntityManager();
}
if (!TransactionSynchronizationManager.isSynchronizationActive()) {
// Indicate that we can't obtain a transactional EntityManager.
return null;
}
// Create a new EntityManager for use within the current transaction.
logger.debug("Opening JPA EntityManager");
EntityManager em =
(!CollectionUtils.isEmpty(properties) ? emf.createEntityManager(properties) : emf.createEntityManager());
if (TransactionSynchronizationManager.isSynchronizationActive()) {
logger.debug("Registering transaction synchronization for JPA EntityManager");
// Use same EntityManager for further JPA actions within the transaction.
// Thread object will get removed by synchronization at transaction completion.
emHolder = new EntityManagerHolder(em);
Object transactionData = prepareTransaction(em, emf);
TransactionSynchronizationManager.registerSynchronization(
new EntityManagerSynchronization(emHolder, emf, transactionData, true));
emHolder.setSynchronizedWithTransaction(true);
TransactionSynchronizationManager.bindResource(emf, emHolder);
}
return em;
}
/**
* Prepare a transaction on the given EntityManager, if possible.
* @param em the EntityManager to prepare
* @param emf the EntityManagerFactory that the EntityManager has been created with
* @return an arbitrary object that holds transaction data, if any
* (to be passed into cleanupTransaction)
* @see JpaDialect#prepareTransaction
*/
private static Object prepareTransaction(EntityManager em, EntityManagerFactory emf) {
if (emf instanceof EntityManagerFactoryInfo) {
EntityManagerFactoryInfo emfInfo = (EntityManagerFactoryInfo) emf;
JpaDialect jpaDialect = emfInfo.getJpaDialect();
if (jpaDialect != null) {
return jpaDialect.prepareTransaction(em,
TransactionSynchronizationManager.isCurrentTransactionReadOnly(),
TransactionSynchronizationManager.getCurrentTransactionName());
}
}
return null;
}
/**
* Prepare a transaction on the given EntityManager, if possible.
* @param transactionData arbitrary object that holds transaction data, if any
* (as returned by prepareTransaction)
* @param emf the EntityManagerFactory that the EntityManager has been created with
* @see JpaDialect#cleanupTransaction
*/
private static void cleanupTransaction(Object transactionData, EntityManagerFactory emf) {
if (emf instanceof EntityManagerFactoryInfo) {
EntityManagerFactoryInfo emfInfo = (EntityManagerFactoryInfo) emf;
JpaDialect jpaDialect = emfInfo.getJpaDialect();
if (jpaDialect != null) {
jpaDialect.cleanupTransaction(transactionData);
}
}
}
/**
* Apply the current transaction timeout, if any, to the given JPA Query object.
* <p>This method sets the JPA 2.0 query hints "javax.persistence.lock.timeout"
* and "javax.persistence.query.timeout" accordingly.
* @param query the JPA Query object
* @param emf JPA EntityManagerFactory that the Query was created for
*/
public static void applyTransactionTimeout(Query query, EntityManagerFactory emf) {
EntityManagerHolder emHolder = (EntityManagerHolder) TransactionSynchronizationManager.getResource(emf);
if (emHolder != null && emHolder.hasTimeout()) {
int timeoutValue = emHolder.getTimeToLiveInSeconds();
query.setHint("javax.persistence.lock.timeout", timeoutValue);
query.setHint("javax.persistence.query.timeout", timeoutValue);
}
}
/**
* Convert the given runtime exception to an appropriate exception from the
* <code>org.springframework.dao</code> hierarchy.
* Return null if no translation is appropriate: any other exception may
* have resulted from user code, and should not be translated.
* <p>The most important cases like object not found or optimistic locking
* failure are covered here. For more fine-granular conversion, JpaAccessor and
* JpaTransactionManager support sophisticated translation of exceptions via a
* JpaDialect.
* @param ex runtime exception that occured
* @return the corresponding DataAccessException instance,
* or <code>null</code> if the exception should not be translated
*/
public static DataAccessException convertJpaAccessExceptionIfPossible(RuntimeException ex) {
// Following the JPA specification, a persistence provider can also
// throw these two exceptions, besides PersistenceException.
if (ex instanceof IllegalStateException) {
return new InvalidDataAccessApiUsageException(ex.getMessage(), ex);
}
if (ex instanceof IllegalArgumentException) {
return new InvalidDataAccessApiUsageException(ex.getMessage(), ex);
}
// Check for well-known PersistenceException subclasses.
if (ex instanceof EntityNotFoundException) {
return new JpaObjectRetrievalFailureException((EntityNotFoundException) ex);
}
if (ex instanceof NoResultException) {
return new EmptyResultDataAccessException(ex.getMessage(), 1);
}
if (ex instanceof NonUniqueResultException) {
return new IncorrectResultSizeDataAccessException(ex.getMessage(), 1);
}
if (ex instanceof OptimisticLockException) {
return new JpaOptimisticLockingFailureException((OptimisticLockException) ex);
}
if (ex instanceof EntityExistsException) {
return new DataIntegrityViolationException(ex.getMessage(), ex);
}
if (ex instanceof TransactionRequiredException) {
return new InvalidDataAccessApiUsageException(ex.getMessage(), ex);
}
// If we have another kind of PersistenceException, throw it.
if (ex instanceof PersistenceException) {
return new JpaSystemException((PersistenceException) ex);
}
// If we get here, we have an exception that resulted from user code,
// rather than the persistence provider, so we return null to indicate
// that translation should not occur.
return null;
}
/**
* Close the given JPA EntityManager,
* catching and logging any cleanup exceptions thrown.
* @param em the JPA EntityManager to close (may be <code>null</code>)
* @see javax.persistence.EntityManager#close()
*/
public static void closeEntityManager(EntityManager em) {
if (em != null) {
logger.debug("Closing JPA EntityManager");
try {
if (em.isOpen()) {
em.close();
}
}
catch (PersistenceException ex) {
logger.debug("Could not close JPA EntityManager", ex);
}
catch (Throwable ex) {
logger.debug("Unexpected exception on closing JPA EntityManager", ex);
}
}
}
/**
* Callback for resource cleanup at the end of a non-JPA transaction
* (e.g. when participating in a JtaTransactionManager transaction).
* @see org.springframework.transaction.jta.JtaTransactionManager
*/
private static class EntityManagerSynchronization
extends ResourceHolderSynchronization<EntityManagerHolder, EntityManagerFactory>
implements Ordered {
private final Object transactionData;
private final JpaDialect jpaDialect;
private final boolean newEntityManager;
public EntityManagerSynchronization(
EntityManagerHolder emHolder, EntityManagerFactory emf, Object txData, boolean newEm) {
super(emHolder, emf);
this.transactionData = txData;
this.jpaDialect = (emf instanceof EntityManagerFactoryInfo ?
((EntityManagerFactoryInfo) emf).getJpaDialect() : null);
this.newEntityManager = newEm;
}
public int getOrder() {
return ENTITY_MANAGER_SYNCHRONIZATION_ORDER;
}
@Override
protected void flushResource(EntityManagerHolder resourceHolder) {
try {
resourceHolder.getEntityManager().flush();
}
catch (RuntimeException ex) {
if (this.jpaDialect != null) {
throw this.jpaDialect.translateExceptionIfPossible(ex);
}
else {
throw convertJpaAccessExceptionIfPossible(ex);
}
}
}
@Override
protected boolean shouldUnbindAtCompletion() {
return this.newEntityManager;
}
@Override
protected void releaseResource(EntityManagerHolder resourceHolder, EntityManagerFactory resourceKey) {
closeEntityManager(resourceHolder.getEntityManager());
}
@Override
protected void cleanupResource(EntityManagerHolder resourceHolder, EntityManagerFactory resourceKey, boolean committed) {
if (!committed) {
// Clear all pending inserts/updates/deletes in the EntityManager.
// Necessary for pre-bound EntityManagers, to avoid inconsistent state.
resourceHolder.getEntityManager().clear();
}
cleanupTransaction(this.transactionData, resourceKey);
}
}
}
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