001 /**
002 * GRANITE DATA SERVICES
003 * Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
004 *
005 * This file is part of the Granite Data Services Platform.
006 *
007 * Granite Data Services is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * Granite Data Services is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
015 * General Public License for more details.
016 *
017 * You should have received a copy of the GNU Lesser General Public
018 * License along with this library; if not, write to the Free Software
019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
020 * USA, or see <http://www.gnu.org/licenses/>.
021 */
022 package org.granite.gravity.tomcat;
023
024 import java.util.concurrent.atomic.AtomicReference;
025
026 import javax.servlet.http.HttpServletRequest;
027 import javax.servlet.http.HttpServletResponse;
028
029 import org.apache.catalina.CometEvent;
030 import org.granite.gravity.AbstractChannel;
031 import org.granite.gravity.AbstractGravityServlet;
032 import org.granite.gravity.AsyncHttpContext;
033 import org.granite.gravity.Gravity;
034 import org.granite.logging.Logger;
035
036 import flex.messaging.messages.Message;
037
038 /**
039 * @author Franck WOLFF
040 */
041 public class TomcatChannel extends AbstractChannel {
042
043 private static final Logger log = Logger.getLogger(TomcatChannel.class);
044
045 private final AtomicReference<CometEvent> event = new AtomicReference<CometEvent>();
046
047
048 public TomcatChannel(Gravity gravity, String id, TomcatChannelFactory factory, String clientType) {
049 super(gravity, id, factory, clientType);
050 }
051
052 public void setCometEvent(CometEvent event) {
053 if (log.isDebugEnabled())
054 log.debug("Channel: %s got new event: %s", getId(), EventUtil.toString(event));
055
056 // Set this channel's event.
057 CometEvent previousEvent = this.event.getAndSet(event);
058
059 // Normally, we should have only two cases here:
060 //
061 // 1) this.event == null && event != null -> new (re)connect message.
062 // 2) this.event != null && event == null -> timeout.
063 //
064 // Not sure about what should be done if this.event != null && event != null, so
065 // warn about this case and close this.event if it is not the same as the event
066 // parameter.
067 if (previousEvent != null) {
068 if (event != null) {
069 log.warn(
070 "Got a new non null event %s while current event %s isn't null",
071 EventUtil.toString(event), EventUtil.toString(this.event.get())
072 );
073 }
074 if (previousEvent != event) {
075 try {
076 previousEvent.close();
077 }
078 catch (Exception e) {
079 log.debug(e, "Error while closing event");
080 }
081 }
082 }
083
084 // Try to queue receiver if the new event isn't null.
085 if (event != null)
086 queueReceiver();
087 }
088
089 @Override
090 protected boolean hasAsyncHttpContext() {
091 return event.get() != null;
092 }
093
094 @Override
095 protected AsyncHttpContext acquireAsyncHttpContext() {
096
097 CometEvent event = this.event.getAndSet(null);
098 if (event == null)
099 return null;
100
101 AsyncHttpContext context = null;
102
103 try {
104 HttpServletRequest request = null;
105 HttpServletResponse response = null;
106 try {
107 request = event.getHttpServletRequest();
108 response = event.getHttpServletResponse();
109 } catch (Exception e) {
110 log.warn(e, "Illegal event: %s", EventUtil.toString(event));
111 return null;
112 }
113 if (request == null || response == null) {
114 log.warn("Illegal event (request or response is null): %s", EventUtil.toString(event));
115 return null;
116 }
117
118 Message requestMessage = AbstractGravityServlet.getConnectMessage(request);
119 if (requestMessage == null) {
120 log.warn("No request message while running channel: %s", getId());
121 return null;
122 }
123
124 context = new AsyncHttpContext(request, response, requestMessage, event);
125 }
126 finally {
127 if (context == null) {
128 try {
129 event.close();
130 }
131 catch (Exception e) {
132 log.debug(e, "Error while closing event: %s", EventUtil.toString(event));
133 }
134 }
135 }
136
137 return context;
138 }
139
140 @Override
141 protected void releaseAsyncHttpContext(AsyncHttpContext context) {
142 try {
143 if (context != null && context.getObject() != null)
144 ((CometEvent)context.getObject()).close();
145 }
146 catch (Exception e) {
147 log.warn(e, "Could not release event for channel: %s", this);
148 }
149 }
150
151 @Override
152 public void destroy() {
153 try {
154 super.destroy();
155 }
156 finally {
157 close();
158 }
159 }
160
161 public void close() {
162 CometEvent event = this.event.getAndSet(null);
163 if (event != null) {
164 try {
165 event.close();
166 }
167 catch (Exception e) {
168 log.debug(e, "Could not close event: %s for channel: %s", EventUtil.toString(event), this);
169 }
170 }
171 }
172 }