/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.camel.impl;
import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;
import java.util.Stack;
import org.apache.camel.CamelContext;
import org.apache.camel.Exchange;
import org.apache.camel.Message;
import org.apache.camel.Service;
import org.apache.camel.spi.RouteContext;
import org.apache.camel.spi.Synchronization;
import org.apache.camel.spi.SynchronizationVetoable;
import org.apache.camel.spi.TracedRouteNodes;
import org.apache.camel.spi.UnitOfWork;
import org.apache.camel.util.EventHelper;
import org.apache.camel.util.UnitOfWorkHelper;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* The default implementation of {@link org.apache.camel.spi.UnitOfWork}
*
* @version $Revision: 1043879 $
*/
public class DefaultUnitOfWork implements UnitOfWork, Service {
private static final transient Log LOG = LogFactory.getLog(DefaultUnitOfWork.class);
private String id;
private CamelContext context;
private List<Synchronization> synchronizations;
private Message originalInMessage;
private final TracedRouteNodes tracedRouteNodes;
private Set<Object> transactedBy;
private final Stack<RouteContext> routeContextStack = new Stack<RouteContext>();
public DefaultUnitOfWork(Exchange exchange) {
if (LOG.isTraceEnabled()) {
LOG.trace("UnitOfWork created for ExchangeId: " + exchange.getExchangeId() + " with " + exchange);
}
tracedRouteNodes = new DefaultTracedRouteNodes();
context = exchange.getContext();
// TODO: the copy on facade strategy will help us here in the future
// TODO: optimize to only copy original message if enabled to do so in the route
// special for JmsMessage as it can cause it to loose headers later.
// This will be resolved when we get the message facade with copy on write implemented
if (exchange.getIn().getClass().getSimpleName().equals("JmsMessage")) {
this.originalInMessage = new DefaultMessage();
this.originalInMessage.setBody(exchange.getIn().getBody());
// cannot copy headers with a JmsMessage as the underlying javax.jms.Message object goes nuts
} else {
this.originalInMessage = exchange.getIn().copy();
}
// mark the creation time when this Exchange was created
if (exchange.getProperty(Exchange.CREATED_TIMESTAMP) == null) {
exchange.setProperty(Exchange.CREATED_TIMESTAMP, new Date());
}
// fire event
EventHelper.notifyExchangeCreated(exchange.getContext(), exchange);
// register to inflight registry
if (exchange.getContext() != null) {
exchange.getContext().getInflightRepository().add(exchange);
}
}
public void start() throws Exception {
id = null;
}
public void stop() throws Exception {
// need to clean up when we are stopping to not leak memory
if (synchronizations != null) {
synchronizations.clear();
}
if (tracedRouteNodes != null) {
tracedRouteNodes.clear();
}
if (transactedBy != null) {
transactedBy.clear();
}
originalInMessage = null;
if (!routeContextStack.isEmpty()) {
routeContextStack.clear();
}
}
public synchronized void addSynchronization(Synchronization synchronization) {
if (synchronizations == null) {
synchronizations = new ArrayList<Synchronization>();
}
if (LOG.isTraceEnabled()) {
LOG.trace("Adding synchronization " + synchronization);
}
synchronizations.add(synchronization);
}
public synchronized void removeSynchronization(Synchronization synchronization) {
if (synchronizations != null) {
synchronizations.remove(synchronization);
}
}
public void handoverSynchronization(Exchange target) {
if (synchronizations == null || synchronizations.isEmpty()) {
return;
}
Iterator<Synchronization> it = synchronizations.iterator();
while (it.hasNext()) {
Synchronization synchronization = it.next();
boolean handover = true;
if (synchronization instanceof SynchronizationVetoable) {
SynchronizationVetoable veto = (SynchronizationVetoable) synchronization;
handover = veto.allowHandover();
}
if (handover) {
if (LOG.isTraceEnabled()) {
LOG.trace("Handover synchronization " + synchronization + " to: " + target);
}
target.addOnCompletion(synchronization);
// remove it if its handed over
it.remove();
} else {
if (LOG.isTraceEnabled()) {
LOG.trace("Handover not allow for synchronization " + synchronization);
}
}
}
}
public void done(Exchange exchange) {
if (LOG.isTraceEnabled()) {
LOG.trace("UnitOfWork done for ExchangeId: " + exchange.getExchangeId() + " with " + exchange);
}
boolean failed = exchange.isFailed();
// at first done the synchronizations
UnitOfWorkHelper.doneSynchronizations(exchange, synchronizations, LOG);
// then fire event to signal the exchange is done
try {
if (failed) {
EventHelper.notifyExchangeFailed(exchange.getContext(), exchange);
} else {
EventHelper.notifyExchangeDone(exchange.getContext(), exchange);
}
} catch (Throwable e) {
// must catch exceptions to ensure synchronizations is also invoked
LOG.warn("Exception occurred during event notification. This exception will be ignored.", e);
} finally {
// unregister from inflight registry
if (exchange.getContext() != null) {
exchange.getContext().getInflightRepository().remove(exchange);
}
}
}
public String getId() {
if (id == null) {
id = context.getUuidGenerator().generateUuid();
}
return id;
}
public Message getOriginalInMessage() {
return originalInMessage;
}
public TracedRouteNodes getTracedRouteNodes() {
return tracedRouteNodes;
}
public boolean isTransacted() {
return transactedBy != null && !transactedBy.isEmpty();
}
public boolean isTransactedBy(Object transactionDefinition) {
return getTransactedBy().contains(transactionDefinition);
}
public void beginTransactedBy(Object transactionDefinition) {
getTransactedBy().add(transactionDefinition);
}
public void endTransactedBy(Object transactionDefinition) {
getTransactedBy().remove(transactionDefinition);
}
public RouteContext getRouteContext() {
if (routeContextStack.isEmpty()) {
return null;
}
return routeContextStack.peek();
}
public void pushRouteContext(RouteContext routeContext) {
routeContextStack.add(routeContext);
}
public RouteContext popRouteContext() {
if (routeContextStack.isEmpty()) {
return null;
}
return routeContextStack.pop();
}
private Set<Object> getTransactedBy() {
if (transactedBy == null) {
transactedBy = new LinkedHashSet<Object>();
}
return transactedBy;
}
}