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/* * Copyright 2002-2017 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.jms.connection; import javax.jms.Connection; import javax.jms.ConnectionFactory; import javax.jms.JMSException; import javax.jms.QueueConnection; import javax.jms.QueueConnectionFactory; import javax.jms.QueueSession; import javax.jms.Session; import javax.jms.TopicConnection; import javax.jms.TopicConnectionFactory; import javax.jms.TopicSession; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.lang.Nullable; import org.springframework.transaction.support.ResourceHolderSynchronization; import org.springframework.transaction.support.TransactionSynchronizationManager; import org.springframework.util.Assert; /** * Helper class for managing a JMS {@link javax.jms.ConnectionFactory}, in particular * for obtaining transactional JMS resources for a given ConnectionFactory. * * <p>Mainly for internal use within the framework. Used by * {@link org.springframework.jms.core.JmsTemplate} as well as * {@link org.springframework.jms.listener.DefaultMessageListenerContainer}. * * @author Juergen Hoeller * @since 2.0 * @see SmartConnectionFactory */ public abstract class ConnectionFactoryUtils { private static final Log logger = LogFactory.getLog(ConnectionFactoryUtils.class); /** * Release the given Connection, stopping it (if necessary) and eventually closing it. * <p>Checks {@link SmartConnectionFactory#shouldStop}, if available. * This is essentially a more sophisticated version of * {@link org.springframework.jms.support.JmsUtils#closeConnection}. * @param con the Connection to release * (if this is {@code null}, the call will be ignored) * @param cf the ConnectionFactory that the Connection was obtained from * (may be {@code null}) * @param started whether the Connection might have been started by the application * @see SmartConnectionFactory#shouldStop * @see org.springframework.jms.support.JmsUtils#closeConnection */ public static void releaseConnection(@Nullable Connection con, @Nullable ConnectionFactory cf, boolean started) { if (con == null) { return; } if (started && cf instanceof SmartConnectionFactory && ((SmartConnectionFactory) cf).shouldStop(con)) { try { con.stop(); } catch (Throwable ex) { logger.debug("Could not stop JMS Connection before closing it", ex); } } try { con.close(); } catch (Throwable ex) { logger.debug("Could not close JMS Connection", ex); } } /** * Return the innermost target Session of the given Session. If the given * Session is a proxy, it will be unwrapped until a non-proxy Session is * found. Otherwise, the passed-in Session will be returned as-is. * @param session the Session proxy to unwrap * @return the innermost target Session, or the passed-in one if no proxy * @see SessionProxy#getTargetSession() */ public static Session getTargetSession(Session session) { Session sessionToUse = session; while (sessionToUse instanceof SessionProxy) { sessionToUse = ((SessionProxy) sessionToUse).getTargetSession(); } return sessionToUse; } /** * Determine whether the given JMS Session is transactional, that is, * bound to the current thread by Spring's transaction facilities. * @param session the JMS Session to check * @param cf the JMS ConnectionFactory that the Session originated from * @return whether the Session is transactional */ public static boolean isSessionTransactional(@Nullable Session session, @Nullable ConnectionFactory cf) { if (session == null || cf == null) { return false; } JmsResourceHolder resourceHolder = (JmsResourceHolder) TransactionSynchronizationManager.getResource(cf); return (resourceHolder != null && resourceHolder.containsSession(session)); } /** * Obtain a JMS Session that is synchronized with the current transaction, if any. * @param cf the ConnectionFactory to obtain a Session for * @param existingCon the existing JMS Connection to obtain a Session for * (may be {@code null}) * @param synchedLocalTransactionAllowed whether to allow for a local JMS transaction * that is synchronized with a Spring-managed transaction (where the main transaction * might be a JDBC-based one for a specific DataSource, for example), with the JMS * transaction committing right after the main transaction. If not allowed, the given * ConnectionFactory needs to handle transaction enlistment underneath the covers. * @return the transactional Session, or {@code null} if none found * @throws JMSException in case of JMS failure */ @Nullable public static Session getTransactionalSession(final ConnectionFactory cf, @Nullable final Connection existingCon, final boolean synchedLocalTransactionAllowed) throws JMSException { return doGetTransactionalSession(cf, new ResourceFactory() { @Override @Nullable public Session getSession(JmsResourceHolder holder) { return holder.getSession(Session.class, existingCon); } @Override @Nullable public Connection getConnection(JmsResourceHolder holder) { return (existingCon != null ? existingCon : holder.getConnection()); } @Override public Connection createConnection() throws JMSException { return cf.createConnection(); } @Override public Session createSession(Connection con) throws JMSException { return con.createSession(synchedLocalTransactionAllowed, Session.AUTO_ACKNOWLEDGE); } @Override public boolean isSynchedLocalTransactionAllowed() { return synchedLocalTransactionAllowed; } }, true); } /** * Obtain a JMS QueueSession that is synchronized with the current transaction, if any. * <p>Mainly intended for use with the JMS 1.0.2 API. * @param cf the ConnectionFactory to obtain a Session for * @param existingCon the existing JMS Connection to obtain a Session for * (may be {@code null}) * @param synchedLocalTransactionAllowed whether to allow for a local JMS transaction * that is synchronized with a Spring-managed transaction (where the main transaction * might be a JDBC-based one for a specific DataSource, for example), with the JMS * transaction committing right after the main transaction. If not allowed, the given * ConnectionFactory needs to handle transaction enlistment underneath the covers. * @return the transactional Session, or {@code null} if none found * @throws JMSException in case of JMS failure */ @Nullable public static QueueSession getTransactionalQueueSession(final QueueConnectionFactory cf, @Nullable final QueueConnection existingCon, final boolean synchedLocalTransactionAllowed) throws JMSException { return (QueueSession) doGetTransactionalSession(cf, new ResourceFactory() { @Override @Nullable public Session getSession(JmsResourceHolder holder) { return holder.getSession(QueueSession.class, existingCon); } @Override @Nullable public Connection getConnection(JmsResourceHolder holder) { return (existingCon != null ? existingCon : holder.getConnection(QueueConnection.class)); } @Override public Connection createConnection() throws JMSException { return cf.createQueueConnection(); } @Override public Session createSession(Connection con) throws JMSException { return ((QueueConnection) con).createQueueSession(synchedLocalTransactionAllowed, Session.AUTO_ACKNOWLEDGE); } @Override public boolean isSynchedLocalTransactionAllowed() { return synchedLocalTransactionAllowed; } }, true); } /** * Obtain a JMS TopicSession that is synchronized with the current transaction, if any. * <p>Mainly intended for use with the JMS 1.0.2 API. * @param cf the ConnectionFactory to obtain a Session for * @param existingCon the existing JMS Connection to obtain a Session for * (may be {@code null}) * @param synchedLocalTransactionAllowed whether to allow for a local JMS transaction * that is synchronized with a Spring-managed transaction (where the main transaction * might be a JDBC-based one for a specific DataSource, for example), with the JMS * transaction committing right after the main transaction. If not allowed, the given * ConnectionFactory needs to handle transaction enlistment underneath the covers. * @return the transactional Session, or {@code null} if none found * @throws JMSException in case of JMS failure */ @Nullable public static TopicSession getTransactionalTopicSession(final TopicConnectionFactory cf, @Nullable final TopicConnection existingCon, final boolean synchedLocalTransactionAllowed) throws JMSException { return (TopicSession) doGetTransactionalSession(cf, new ResourceFactory() { @Override @Nullable public Session getSession(JmsResourceHolder holder) { return holder.getSession(TopicSession.class, existingCon); } @Override @Nullable public Connection getConnection(JmsResourceHolder holder) { return (existingCon != null ? existingCon : holder.getConnection(TopicConnection.class)); } @Override public Connection createConnection() throws JMSException { return cf.createTopicConnection(); } @Override public Session createSession(Connection con) throws JMSException { return ((TopicConnection) con).createTopicSession(synchedLocalTransactionAllowed, Session.AUTO_ACKNOWLEDGE); } @Override public boolean isSynchedLocalTransactionAllowed() { return synchedLocalTransactionAllowed; } }, true); } /** * Obtain a JMS Session that is synchronized with the current transaction, if any. * <p>This {@code doGetTransactionalSession} variant always starts the underlying * JMS Connection, assuming that the Session will be used for receiving messages. * @param connectionFactory the JMS ConnectionFactory to bind for * (used as TransactionSynchronizationManager key) * @param resourceFactory the ResourceFactory to use for extracting or creating * JMS resources * @return the transactional Session, or {@code null} if none found * @throws JMSException in case of JMS failure * @see #doGetTransactionalSession(javax.jms.ConnectionFactory, ResourceFactory, boolean) */ @Nullable public static Session doGetTransactionalSession(ConnectionFactory connectionFactory, ResourceFactory resourceFactory) throws JMSException { return doGetTransactionalSession(connectionFactory, resourceFactory, true); } /** * Obtain a JMS Session that is synchronized with the current transaction, if any. * @param connectionFactory the JMS ConnectionFactory to bind for * (used as TransactionSynchronizationManager key) * @param resourceFactory the ResourceFactory to use for extracting or creating * JMS resources * @param startConnection whether the underlying JMS Connection approach should be * started in order to allow for receiving messages. Note that a reused Connection * may already have been started before, even if this flag is {@code false}. * @return the transactional Session, or {@code null} if none found * @throws JMSException in case of JMS failure */ @Nullable public static Session doGetTransactionalSession(ConnectionFactory connectionFactory, ResourceFactory resourceFactory, boolean startConnection) throws JMSException { Assert.notNull(connectionFactory, "ConnectionFactory must not be null"); Assert.notNull(resourceFactory, "ResourceFactory must not be null"); JmsResourceHolder resourceHolder = (JmsResourceHolder) TransactionSynchronizationManager .getResource(connectionFactory); if (resourceHolder != null) { Session session = resourceFactory.getSession(resourceHolder); if (session != null) { if (startConnection) { Connection con = resourceFactory.getConnection(resourceHolder); if (con != null) { con.start(); } } return session; } if (resourceHolder.isFrozen()) { return null; } } if (!TransactionSynchronizationManager.isSynchronizationActive()) { return null; } JmsResourceHolder resourceHolderToUse = resourceHolder; if (resourceHolderToUse == null) { resourceHolderToUse = new JmsResourceHolder(connectionFactory); } Connection con = resourceFactory.getConnection(resourceHolderToUse); Session session = null; try { boolean isExistingCon = (con != null); if (!isExistingCon) { con = resourceFactory.createConnection(); resourceHolderToUse.addConnection(con); } session = resourceFactory.createSession(con); resourceHolderToUse.addSession(session, con); if (startConnection) { con.start(); } } catch (JMSException ex) { if (session != null) { try { session.close(); } catch (Throwable ex2) { // ignore } } if (con != null) { try { con.close(); } catch (Throwable ex2) { // ignore } } throw ex; } if (resourceHolderToUse != resourceHolder) { TransactionSynchronizationManager.registerSynchronization(new JmsResourceSynchronization( resourceHolderToUse, connectionFactory, resourceFactory.isSynchedLocalTransactionAllowed())); resourceHolderToUse.setSynchronizedWithTransaction(true); TransactionSynchronizationManager.bindResource(connectionFactory, resourceHolderToUse); } return session; } /** * Callback interface for resource creation. * Serving as argument for the {@code doGetTransactionalSession} method. */ public interface ResourceFactory { /** * Fetch an appropriate Session from the given JmsResourceHolder. * @param holder the JmsResourceHolder * @return an appropriate Session fetched from the holder, * or {@code null} if none found */ @Nullable Session getSession(JmsResourceHolder holder); /** * Fetch an appropriate Connection from the given JmsResourceHolder. * @param holder the JmsResourceHolder * @return an appropriate Connection fetched from the holder, * or {@code null} if none found */ @Nullable Connection getConnection(JmsResourceHolder holder); /** * Create a new JMS Connection for registration with a JmsResourceHolder. * @return the new JMS Connection * @throws JMSException if thrown by JMS API methods */ Connection createConnection() throws JMSException; /** * Create a new JMS Session for registration with a JmsResourceHolder. * @param con the JMS Connection to create a Session for * @return the new JMS Session * @throws JMSException if thrown by JMS API methods */ Session createSession(Connection con) throws JMSException; /** * Return whether to allow for a local JMS transaction that is synchronized with * a Spring-managed transaction (where the main transaction might be a JDBC-based * one for a specific DataSource, for example), with the JMS transaction * committing right after the main transaction. * @return whether to allow for synchronizing a local JMS transaction */ boolean isSynchedLocalTransactionAllowed(); } /** * Callback for resource cleanup at the end of a non-native JMS transaction * (e.g. when participating in a JtaTransactionManager transaction). * @see org.springframework.transaction.jta.JtaTransactionManager */ private static class JmsResourceSynchronization extends ResourceHolderSynchronization<JmsResourceHolder, Object> { private final boolean transacted; public JmsResourceSynchronization(JmsResourceHolder resourceHolder, Object resourceKey, boolean transacted) { super(resourceHolder, resourceKey); this.transacted = transacted; } @Override protected boolean shouldReleaseBeforeCompletion() { return !this.transacted; } @Override protected void processResourceAfterCommit(JmsResourceHolder resourceHolder) { try { resourceHolder.commitAll(); } catch (JMSException ex) { throw new SynchedLocalTransactionFailedException("Local JMS transaction failed to commit", ex); } } @Override protected void releaseResource(JmsResourceHolder resourceHolder, Object resourceKey) { resourceHolder.closeAll(); } } }