/*
* Copyright 2002-2009 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.io.Serializable;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.LinkedHashSet;
import java.util.Map;
import java.util.Set;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.TransactionRequiredException;
import javax.persistence.spi.PersistenceUnitInfo;
import javax.persistence.spi.PersistenceUnitTransactionType;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.core.Ordered;
import org.springframework.dao.DataAccessException;
import org.springframework.dao.support.PersistenceExceptionTranslator;
import org.springframework.transaction.support.ResourceHolderSynchronization;
import org.springframework.transaction.support.TransactionSynchronizationManager;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.CollectionUtils;
/**
* Factory for dynamic EntityManager proxies that follow the JPA spec's
* semantics for "extended" EntityManagers.
*
* <p>Supports explicit joining of a transaction through the
* <code>joinTransaction()</code> method ("application-managed extended
* EntityManager") as well as automatic joining on each operation
* ("container-managed extended EntityManager").
*
* @author Rod Johnson
* @author Juergen Hoeller
* @since 2.0
*/
public abstract class ExtendedEntityManagerCreator {
/**
* Create an EntityManager that can join transactions with the
* <code>joinTransaction()</code> method, but is not automatically
* managed by the container.
* @param rawEntityManager raw EntityManager
* @param plusOperations an implementation of the EntityManagerPlusOperations
* interface, if those operations should be exposed (may be <code>null</code>)
* @return an application-managed EntityManager that can join transactions
* but does not participate in them automatically
*/
public static EntityManager createApplicationManagedEntityManager(
EntityManager rawEntityManager, EntityManagerPlusOperations plusOperations) {
return createProxy(rawEntityManager, null, null, plusOperations, null, null, false);
}
/**
* Create an EntityManager that can join transactions with the
* <code>joinTransaction()</code> method, but is not automatically
* managed by the container.
* @param rawEntityManager raw EntityManager
* @param plusOperations an implementation of the EntityManagerPlusOperations
* interface, if those operations should be exposed (may be <code>null</code>)
* @param exceptionTranslator the exception translator to use for translating
* JPA commit/rollback exceptions during transaction synchronization
* (may be <code>null</code>)
* @return an application-managed EntityManager that can join transactions
* but does not participate in them automatically
*/
public static EntityManager createApplicationManagedEntityManager(
EntityManager rawEntityManager, EntityManagerPlusOperations plusOperations,
PersistenceExceptionTranslator exceptionTranslator) {
return createProxy(rawEntityManager, null, null, plusOperations, exceptionTranslator, null, false);
}
/**
* Create an EntityManager that can join transactions with the
* <code>joinTransaction()</code> method, but is not automatically
* managed by the container.
* @param rawEntityManager raw EntityManager
* @param emfInfo the EntityManagerFactoryInfo to obtain the
* EntityManagerPlusOperations and PersistenceUnitInfo from
* @return an application-managed EntityManager that can join transactions
* but does not participate in them automatically
*/
public static EntityManager createApplicationManagedEntityManager(
EntityManager rawEntityManager, EntityManagerFactoryInfo emfInfo) {
return createProxy(rawEntityManager, emfInfo, false);
}
/**
* Create an EntityManager that automatically joins transactions on each
* operation in a transaction.
* @param rawEntityManager raw EntityManager
* @param plusOperations an implementation of the EntityManagerPlusOperations
* interface, if those operations should be exposed (may be <code>null</code>)
* @return a container-managed EntityManager that will automatically participate
* in any managed transaction
*/
public static EntityManager createContainerManagedEntityManager(
EntityManager rawEntityManager, EntityManagerPlusOperations plusOperations) {
return createProxy(rawEntityManager, null, null, plusOperations, null, null, true);
}
/**
* Create an EntityManager that automatically joins transactions on each
* operation in a transaction.
* @param rawEntityManager raw EntityManager
* @param plusOperations an implementation of the EntityManagerPlusOperations
* interface, if those operations should be exposed (may be <code>null</code>)
* @param exceptionTranslator the exception translator to use for translating
* JPA commit/rollback exceptions during transaction synchronization
* (may be <code>null</code>)
* @return a container-managed EntityManager that will automatically participate
* in any managed transaction
*/
public static EntityManager createContainerManagedEntityManager(
EntityManager rawEntityManager, EntityManagerPlusOperations plusOperations,
PersistenceExceptionTranslator exceptionTranslator) {
return createProxy(rawEntityManager, null, null, plusOperations, exceptionTranslator, null, true);
}
/**
* Create an EntityManager that automatically joins transactions on each
* operation in a transaction.
* @param rawEntityManager raw EntityManager
* @param emfInfo the EntityManagerFactoryInfo to obtain the
* EntityManagerPlusOperations and PersistenceUnitInfo from
* @return a container-managed EntityManager that will automatically participate
* in any managed transaction
*/
public static EntityManager createContainerManagedEntityManager(
EntityManager rawEntityManager, EntityManagerFactoryInfo emfInfo) {
return createProxy(rawEntityManager, emfInfo, true);
}
/**
* Create an EntityManager that automatically joins transactions on each
* operation in a transaction.
* @param emf the EntityManagerFactory to create the EntityManager with.
* If this implements the EntityManagerFactoryInfo interface, appropriate handling
* of the native EntityManagerFactory and available EntityManagerPlusOperations
* will automatically apply.
* @return a container-managed EntityManager that will automatically participate
* in any managed transaction
* @see javax.persistence.EntityManagerFactory#createEntityManager()
*/
public static EntityManager createContainerManagedEntityManager(EntityManagerFactory emf) {
return createContainerManagedEntityManager(emf, null);
}
/**
* Create an EntityManager that automatically joins transactions on each
* operation in a transaction.
* @param emf the EntityManagerFactory to create the EntityManager with.
* If this implements the EntityManagerFactoryInfo interface, appropriate handling
* of the native EntityManagerFactory and available EntityManagerPlusOperations
* will automatically apply.
* @param properties the properties to be passed into the <code>createEntityManager</code>
* call (may be <code>null</code>)
* @return a container-managed EntityManager that will automatically participate
* in any managed transaction
* @see javax.persistence.EntityManagerFactory#createEntityManager(java.util.Map)
*/
public static EntityManager createContainerManagedEntityManager(EntityManagerFactory emf, Map properties) {
Assert.notNull(emf, "EntityManagerFactory must not be null");
if (emf instanceof EntityManagerFactoryInfo) {
EntityManagerFactoryInfo emfInfo = (EntityManagerFactoryInfo) emf;
EntityManagerFactory nativeEmf = emfInfo.getNativeEntityManagerFactory();
EntityManager rawEntityManager = (!CollectionUtils.isEmpty(properties) ?
nativeEmf.createEntityManager(properties) : nativeEmf.createEntityManager());
return createProxy(rawEntityManager, emfInfo, true);
}
else {
EntityManager rawEntityManager = (!CollectionUtils.isEmpty(properties) ?
emf.createEntityManager(properties) : emf.createEntityManager());
return createProxy(rawEntityManager, null, null, null, null, null, true);
}
}
/**
* Actually create the EntityManager proxy.
* @param rawEntityManager raw EntityManager
* @param emfInfo the EntityManagerFactoryInfo to obtain the
* EntityManagerPlusOperations and PersistenceUnitInfo from
* @param containerManaged whether to follow container-managed EntityManager
* or application-managed EntityManager semantics
* @return the EntityManager proxy
*/
private static EntityManager createProxy(
EntityManager rawEntityManager, EntityManagerFactoryInfo emfInfo, boolean containerManaged) {
Assert.notNull(emfInfo, "EntityManagerFactoryInfo must not be null");
JpaDialect jpaDialect = emfInfo.getJpaDialect();
EntityManagerPlusOperations plusOperations = null;
if (jpaDialect != null && jpaDialect.supportsEntityManagerPlusOperations()) {
plusOperations = jpaDialect.getEntityManagerPlusOperations(rawEntityManager);
}
PersistenceUnitInfo pui = emfInfo.getPersistenceUnitInfo();
Boolean jta = (pui != null ? pui.getTransactionType() == PersistenceUnitTransactionType.JTA : null);
return createProxy(rawEntityManager, emfInfo.getEntityManagerInterface(),
emfInfo.getBeanClassLoader(), plusOperations, jpaDialect, jta, containerManaged);
}
/**
* Actually create the EntityManager proxy.
* @param rawEm raw EntityManager
* @param emIfc the (potentially vendor-specific) EntityManager
* interface to proxy, or <code>null</code> for default detection of all interfaces
* @param plusOperations an implementation of the EntityManagerPlusOperations
* interface, if those operations should be exposed (may be <code>null</code>)
* @param exceptionTranslator the PersistenceException translator to use
* @param jta whether to create a JTA-aware EntityManager
* (or <code>null</code> if not known in advance)
* @param containerManaged whether to follow container-managed EntityManager
* or application-managed EntityManager semantics
* @return the EntityManager proxy
*/
private static EntityManager createProxy(
EntityManager rawEm, Class<? extends EntityManager> emIfc, ClassLoader cl,
EntityManagerPlusOperations plusOperations, PersistenceExceptionTranslator exceptionTranslator,
Boolean jta, boolean containerManaged) {
Assert.notNull(rawEm, "EntityManager must not be null");
Set<Class> ifcs = new LinkedHashSet<Class>();
if (emIfc != null) {
ifcs.add(emIfc);
}
else {
ifcs.addAll(ClassUtils.getAllInterfacesForClassAsSet(rawEm.getClass(), cl));
}
ifcs.add(EntityManagerProxy.class);
if (plusOperations != null) {
ifcs.add(EntityManagerPlusOperations.class);
}
return (EntityManager) Proxy.newProxyInstance(
(cl != null ? cl : ExtendedEntityManagerCreator.class.getClassLoader()),
ifcs.toArray(new Class[ifcs.size()]),
new ExtendedEntityManagerInvocationHandler(
rawEm, plusOperations, exceptionTranslator, jta, containerManaged));
}
/**
* InvocationHandler for extended EntityManagers as defined in the JPA spec.
*/
private static class ExtendedEntityManagerInvocationHandler implements InvocationHandler, Serializable {
private static final Log logger = LogFactory.getLog(ExtendedEntityManagerInvocationHandler.class);
private final EntityManager target;
private final EntityManagerPlusOperations plusOperations;
private final PersistenceExceptionTranslator exceptionTranslator;
private final boolean containerManaged;
private boolean jta;
private ExtendedEntityManagerInvocationHandler(
EntityManager target, EntityManagerPlusOperations plusOperations,
PersistenceExceptionTranslator exceptionTranslator, Boolean jta, boolean containerManaged) {
this.target = target;
this.plusOperations = plusOperations;
this.exceptionTranslator = exceptionTranslator;
this.jta = (jta != null ? jta : isJtaEntityManager());
this.containerManaged = containerManaged;
}
private boolean isJtaEntityManager() {
try {
this.target.getTransaction();
return false;
}
catch (IllegalStateException ex) {
logger.debug("Cannot access EntityTransaction handle - assuming we're in a JTA environment");
return true;
}
}
public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
// Invocation on EntityManager interface coming in...
if (method.getName().equals("equals")) {
// Only consider equal when proxies are identical.
return (proxy == args[0]);
}
else if (method.getName().equals("hashCode")) {
// Use hashCode of EntityManager proxy.
return hashCode();
}
else if (method.getName().equals("getTargetEntityManager")) {
// Handle EntityManagerProxy interface.
return this.target;
}
else if (method.getName().equals("unwrap")) {
// Handle JPA 2.0 unwrap method - could be a proxy match.
Class targetClass = (Class) args[0];
if (targetClass == null || targetClass.isInstance(proxy)) {
return proxy;
}
}
else if (method.getName().equals("isOpen")) {
if (this.containerManaged) {
return true;
}
}
else if (method.getName().equals("close")) {
if (this.containerManaged) {
throw new IllegalStateException("Invalid usage: Cannot close a container-managed EntityManager");
}
}
else if (method.getName().equals("getTransaction")) {
if (this.containerManaged) {
throw new IllegalStateException(
"Cannot execute getTransaction() on a container-managed EntityManager");
}
}
else if (method.getName().equals("joinTransaction")) {
doJoinTransaction(true);
return null;
}
// Do automatic joining if required.
if (this.containerManaged && method.getDeclaringClass().isInterface()) {
doJoinTransaction(false);
}
// Invoke method on current EntityManager.
try {
if (method.getDeclaringClass().equals(EntityManagerPlusOperations.class)) {
return method.invoke(this.plusOperations, args);
}
else {
return method.invoke(this.target, args);
}
}
catch (InvocationTargetException ex) {
throw ex.getTargetException();
}
}
/**
* Join an existing transaction, if not already joined.
* @param enforce whether to enforce the transaction
* (i.e. whether failure to join is considered fatal)
*/
private void doJoinTransaction(boolean enforce) {
if (this.jta) {
// Let's try whether we're in a JTA transaction.
try {
this.target.joinTransaction();
logger.debug("Joined JTA transaction");
}
catch (TransactionRequiredException ex) {
if (!enforce) {
logger.debug("No JTA transaction to join: " + ex);
}
else {
throw ex;
}
}
}
else {
if (TransactionSynchronizationManager.isSynchronizationActive()) {
if (!TransactionSynchronizationManager.hasResource(this.target) &&
!this.target.getTransaction().isActive()) {
enlistInCurrentTransaction();
}
logger.debug("Joined local transaction");
}
else {
if (!enforce) {
logger.debug("No local transaction to join");
}
else {
throw new TransactionRequiredException("No local transaction to join");
}
}
}
}
/**
* Enlist this application-managed EntityManager in the current transaction.
*/
private void enlistInCurrentTransaction() {
// Resource local transaction, need to acquire the EntityTransaction,
// start a transaction now and enlist a synchronization for
// commit or rollback later.
EntityTransaction et = this.target.getTransaction();
et.begin();
if (logger.isDebugEnabled()) {
logger.debug("Starting resource local transaction on application-managed " +
"EntityManager [" + this.target + "]");
}
ExtendedEntityManagerSynchronization extendedEntityManagerSynchronization =
new ExtendedEntityManagerSynchronization(this.target, this.exceptionTranslator);
TransactionSynchronizationManager.bindResource(this.target,
extendedEntityManagerSynchronization);
TransactionSynchronizationManager.registerSynchronization(extendedEntityManagerSynchronization);
}
}
/**
* TransactionSynchronization enlisting an extended EntityManager
* with a current Spring transaction.
*/
private static class ExtendedEntityManagerSynchronization
extends ResourceHolderSynchronization<EntityManagerHolder, EntityManager>
implements Ordered {
private final EntityManager entityManager;
private final PersistenceExceptionTranslator exceptionTranslator;
public ExtendedEntityManagerSynchronization(
EntityManager em, PersistenceExceptionTranslator exceptionTranslator) {
super(new EntityManagerHolder(em), em);
this.entityManager = em;
this.exceptionTranslator = exceptionTranslator;
}
public int getOrder() {
return EntityManagerFactoryUtils.ENTITY_MANAGER_SYNCHRONIZATION_ORDER + 1;
}
@Override
protected void flushResource(EntityManagerHolder resourceHolder) {
try {
this.entityManager.flush();
}
catch (RuntimeException ex) {
throw convertException(ex);
}
}
@Override
protected boolean shouldReleaseBeforeCompletion() {
return false;
}
@Override
public void afterCommit() {
super.afterCommit();
// Trigger commit here to let exceptions propagate to the caller.
try {
this.entityManager.getTransaction().commit();
}
catch (RuntimeException ex) {
throw convertException(ex);
}
}
@Override
public void afterCompletion(int status) {
super.afterCompletion(status);
if (status != STATUS_COMMITTED) {
// Haven't had an afterCommit call: trigger a rollback.
try {
this.entityManager.getTransaction().rollback();
}
catch (RuntimeException ex) {
throw convertException(ex);
}
}
}
private RuntimeException convertException(RuntimeException ex) {
DataAccessException daex = (this.exceptionTranslator != null) ?
this.exceptionTranslator.translateExceptionIfPossible(ex) :
EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(ex);
return (daex != null ? daex : ex);
}
}
}
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