/**
* 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.activemq.web;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Semaphore;
import javax.jms.Connection;
import javax.jms.ConnectionFactory;
import javax.jms.DeliveryMode;
import javax.jms.Destination;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageConsumer;
import javax.jms.MessageProducer;
import javax.jms.Session;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionActivationListener;
import javax.servlet.http.HttpSessionBindingEvent;
import javax.servlet.http.HttpSessionBindingListener;
import javax.servlet.http.HttpSessionEvent;
import org.apache.activemq.ActiveMQConnectionFactory;
import org.apache.activemq.MessageAvailableConsumer;
import org.apache.activemq.camel.component.ActiveMQComponent;
import org.apache.activemq.camel.component.ActiveMQConfiguration;
import org.apache.activemq.pool.PooledConnectionFactory;
import org.apache.camel.CamelContext;
import org.apache.camel.ProducerTemplate;
import org.apache.camel.impl.DefaultCamelContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import sun.util.logging.resources.logging;
/**
* Represents a messaging client used from inside a web container typically
* stored inside a HttpSession TODO controls to prevent DOS attacks with users
* requesting many consumers TODO configure consumers with small prefetch.
*
* @version $Revision: 1.1.1.1 $
*/
public class WebClient implements HttpSessionActivationListener, HttpSessionBindingListener, Externalizable {
public static final String WEB_CLIENT_ATTRIBUTE = "org.apache.activemq.webclient";
public static final String CONNECTION_FACTORY_ATTRIBUTE = "org.apache.activemq.connectionFactory";
public static final String CONNECTION_FACTORY_PREFETCH_PARAM = "org.apache.activemq.connectionFactory.prefetch";
public static final String CONNECTION_FACTORY_OPTIMIZE_ACK_PARAM = "org.apache.activemq.connectionFactory.optimizeAck";
public static final String BROKER_URL_INIT_PARAM = "org.apache.activemq.brokerURL";
private static final Log LOG = LogFactory.getLog(WebClient.class);
private static transient ConnectionFactory factory;
private transient Map<Destination, MessageConsumer> consumers = new HashMap<Destination, MessageConsumer>();
private transient Connection connection;
private transient Session session;
private transient MessageProducer producer;
private int deliveryMode = DeliveryMode.NON_PERSISTENT;
private final Semaphore semaphore = new Semaphore(1);
private CamelContext camelContext;
private ProducerTemplate producerTemplate;
public WebClient() {
if (factory == null) {
throw new IllegalStateException("initContext(ServletContext) not called");
}
}
/**
* Helper method to get the client for the current session, lazily creating
* a client if there is none currently
*
* @param request is the current HTTP request
* @return the current client or a newly creates
*/
public static WebClient getWebClient(HttpServletRequest request) {
HttpSession session = request.getSession(true);
WebClient client = getWebClient(session);
if (client == null || client.isClosed()) {
client = WebClient.createWebClient(request);
session.setAttribute(WEB_CLIENT_ATTRIBUTE, client);
}
return client;
}
/**
* @return the web client for the current HTTP session or null if there is
* not a web client created yet
*/
public static WebClient getWebClient(HttpSession session) {
return (WebClient)session.getAttribute(WEB_CLIENT_ATTRIBUTE);
}
public static void initContext(ServletContext context) {
initConnectionFactory(context);
context.setAttribute("webClients", new HashMap<String, WebClient>());
}
public int getDeliveryMode() {
return deliveryMode;
}
public void setDeliveryMode(int deliveryMode) {
this.deliveryMode = deliveryMode;
}
public synchronized void closeConsumers() {
for (Iterator<MessageConsumer> it = consumers.values().iterator(); it.hasNext();) {
MessageConsumer consumer = it.next();
it.remove();
try {
consumer.setMessageListener(null);
if (consumer instanceof MessageAvailableConsumer) {
((MessageAvailableConsumer)consumer).setAvailableListener(null);
}
consumer.close();
} catch (JMSException e) {
LOG.debug("caught exception closing consumer", e);
}
}
}
public synchronized void close() {
try {
closeConsumers();
if (connection != null) {
connection.close();
}
if (producerTemplate != null) {
producerTemplate.stop();
}
} catch (Exception e) {
LOG.debug("caught exception closing consumer", e);
} finally {
producer = null;
session = null;
connection = null;
producerTemplate = null;
if (consumers != null) {
consumers.clear();
}
consumers = null;
}
}
public boolean isClosed() {
return consumers == null;
}
public void writeExternal(ObjectOutput out) throws IOException {
if (consumers != null) {
out.write(consumers.size());
Iterator<Destination> i = consumers.keySet().iterator();
while (i.hasNext()) {
out.writeObject(i.next().toString());
}
} else {
out.write(-1);
}
}
public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
int size = in.readInt();
if (size >= 0) {
consumers = new HashMap<Destination, MessageConsumer>();
for (int i = 0; i < size; i++) {
String destinationName = in.readObject().toString();
try {
Destination destination = destinationName.startsWith("topic://") ? (Destination)getSession().createTopic(destinationName) : (Destination)getSession().createQueue(destinationName);
consumers.put(destination, getConsumer(destination, true));
} catch (JMSException e) {
LOG.debug("Caought Exception ", e);
IOException ex = new IOException(e.getMessage());
ex.initCause(e.getCause() != null ? e.getCause() : e);
throw ex;
}
}
}
}
public void send(Destination destination, Message message) throws JMSException {
getProducer().send(destination, message);
if (LOG.isDebugEnabled()) {
LOG.debug("Sent! to destination: " + destination + " message: " + message);
}
}
public void send(Destination destination, Message message, boolean persistent, int priority, long timeToLive) throws JMSException {
int deliveryMode = persistent ? DeliveryMode.PERSISTENT : DeliveryMode.NON_PERSISTENT;
getProducer().send(destination, message, deliveryMode, priority, timeToLive);
if (LOG.isDebugEnabled()) {
LOG.debug("Sent! to destination: " + destination + " message: " + message);
}
}
public Session getSession() throws JMSException {
if (session == null) {
session = createSession();
}
return session;
}
public Connection getConnection() throws JMSException {
if (connection == null) {
connection = factory.createConnection();
connection.start();
}
return connection;
}
protected static synchronized void initConnectionFactory(ServletContext servletContext) {
if (factory == null) {
factory = (ConnectionFactory)servletContext.getAttribute(CONNECTION_FACTORY_ATTRIBUTE);
}
if (factory == null) {
String brokerURL = servletContext.getInitParameter(BROKER_URL_INIT_PARAM);
LOG.debug("Value of: " + BROKER_URL_INIT_PARAM + " is: " + brokerURL);
if (brokerURL == null) {
throw new IllegalStateException("missing brokerURL (specified via " + BROKER_URL_INIT_PARAM + " init-Param");
}
ActiveMQConnectionFactory amqfactory = new ActiveMQConnectionFactory(brokerURL);
// Set prefetch policy for factory
if (servletContext.getInitParameter(CONNECTION_FACTORY_PREFETCH_PARAM) != null) {
int prefetch = Integer.valueOf(servletContext.getInitParameter(CONNECTION_FACTORY_PREFETCH_PARAM)).intValue();
amqfactory.getPrefetchPolicy().setAll(prefetch);
}
// Set optimize acknowledge setting
if (servletContext.getInitParameter(CONNECTION_FACTORY_OPTIMIZE_ACK_PARAM) != null) {
boolean optimizeAck = Boolean.valueOf(servletContext.getInitParameter(CONNECTION_FACTORY_OPTIMIZE_ACK_PARAM)).booleanValue();
amqfactory.setOptimizeAcknowledge(optimizeAck);
}
factory = amqfactory;
servletContext.setAttribute(CONNECTION_FACTORY_ATTRIBUTE, factory);
}
}
public synchronized CamelContext getCamelContext() {
if (camelContext == null) {
LOG.debug("Creating camel context");
camelContext = new DefaultCamelContext();
ActiveMQConfiguration conf = new ActiveMQConfiguration();
conf.setConnectionFactory(new PooledConnectionFactory((ActiveMQConnectionFactory)factory));
ActiveMQComponent component = new ActiveMQComponent(conf);
camelContext.addComponent("activemq", component);
}
return camelContext;
}
public synchronized ProducerTemplate getProducerTemplate() throws Exception {
if (producerTemplate == null) {
LOG.debug("Creating producer template");
producerTemplate = getCamelContext().createProducerTemplate();
producerTemplate.start();
}
return producerTemplate;
}
public synchronized MessageProducer getProducer() throws JMSException {
if (producer == null) {
producer = getSession().createProducer(null);
producer.setDeliveryMode(deliveryMode);
}
return producer;
}
public void setProducer(MessageProducer producer) {
this.producer = producer;
}
public synchronized MessageConsumer getConsumer(Destination destination) throws JMSException {
return getConsumer(destination, true);
}
public synchronized MessageConsumer getConsumer(Destination destination, boolean create) throws JMSException {
MessageConsumer consumer = consumers.get(destination);
if (create && consumer == null) {
consumer = getSession().createConsumer(destination);
consumers.put(destination, consumer);
}
return consumer;
}
public synchronized void closeConsumer(Destination destination) throws JMSException {
MessageConsumer consumer = consumers.get(destination);
if (consumer != null) {
consumers.remove(destination);
consumer.setMessageListener(null);
if (consumer instanceof MessageAvailableConsumer) {
((MessageAvailableConsumer)consumer).setAvailableListener(null);
}
consumer.close();
}
}
public synchronized List<MessageConsumer> getConsumers() {
return new ArrayList<MessageConsumer>(consumers.values());
}
protected Session createSession() throws JMSException {
return getConnection().createSession(false, Session.AUTO_ACKNOWLEDGE);
}
public Semaphore getSemaphore() {
return semaphore;
}
public void sessionWillPassivate(HttpSessionEvent event) {
close();
}
public void sessionDidActivate(HttpSessionEvent event) {
}
public void valueBound(HttpSessionBindingEvent event) {
}
public void valueUnbound(HttpSessionBindingEvent event) {
close();
}
protected static WebClient createWebClient(HttpServletRequest request) {
return new WebClient();
}
}