1 //
2 // ========================================================================
3 // Copyright (c) 1995-2013 Mort Bay Consulting Pty. Ltd.
4 // ------------------------------------------------------------------------
5 // All rights reserved. This program and the accompanying materials
6 // are made available under the terms of the Eclipse Public License v1.0
7 // and Apache License v2.0 which accompanies this distribution.
8 //
9 // The Eclipse Public License is available at
10 // http://www.eclipse.org/legal/epl-v10.html
11 //
12 // The Apache License v2.0 is available at
13 // http://www.opensource.org/licenses/apache2.0.php
14 //
15 // You may elect to redistribute this code under either of these licenses.
16 // ========================================================================
17 //
18
19 package org.eclipse.jetty.websocket.servlet;
20
21 import java.io.IOException;
22
23 import javax.servlet.ServletException;
24 import javax.servlet.http.HttpServlet;
25 import javax.servlet.http.HttpServletRequest;
26 import javax.servlet.http.HttpServletResponse;
27
28 import org.eclipse.jetty.websocket.api.WebSocketBehavior;
29 import org.eclipse.jetty.websocket.api.WebSocketPolicy;
30 import org.eclipse.jetty.websocket.api.annotations.WebSocket;
31
32 /**
33 * Abstract Servlet used to bridge the Servlet API to the WebSocket API.
34 * <p>
35 * To use this servlet, you will be required to register your websockets with the {@link WebSocketServletFactory} so that it can create your websockets under the
36 * appropriate conditions.
37 * <p>
38 * The most basic implementation would be as follows.
39 *
40 * <pre>
41 * package my.example;
42 *
43 * import org.eclipse.jetty.websocket.servlet.WebSocketServlet;
44 * import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
45 *
46 * public class MyEchoServlet extends WebSocketServlet
47 * {
48 * @Override
49 * public void configure(WebSocketServletFactory factory)
50 * {
51 * // set a 10 second idle timeout
52 * factory.getPolicy().setIdleTimeout(10000);
53 * // register my socket
54 * factory.register(MyEchoSocket.class);
55 * }
56 * }
57 * </pre>
58 *
59 * Note: that only request that conforms to a "WebSocket: Upgrade" handshake request will trigger the {@link WebSocketServletFactory} handling of creating
60 * WebSockets.<br>
61 * All other requests are treated as normal servlet requests.
62 *
63 * <p>
64 * <b>Configuration / Init-Parameters:</b><br>
65 * Note: If you use the {@link WebSocket @WebSocket} annotation, these configuration settings can be specified on a per WebSocket basis, vs a per Servlet
66 * basis.
67 *
68 * <dl>
69 * <dt>maxIdleTime</dt>
70 * <dd>set the time in ms that a websocket may be idle before closing<br>
71 *
72 * <dt>maxTextMessageSize</dt>
73 * <dd>set the size in UTF-8 bytes that a websocket may be accept as a Text Message before closing<br>
74 *
75 * <dt>maxBinaryMessageSize</dt>
76 * <dd>set the size in bytes that a websocket may be accept as a Binary Message before closing<br>
77 *
78 * <dt>inputBufferSize</dt>
79 * <dd>set the size in bytes of the buffer used to read raw bytes from the network layer<br>
80 * </dl>
81 */
82 @SuppressWarnings("serial")
83 public abstract class WebSocketServlet extends HttpServlet
84 {
85 private WebSocketServletFactory factory;
86
87 public abstract void configure(WebSocketServletFactory factory);
88
89 @Override
90 public void destroy()
91 {
92 factory.cleanup();
93 }
94
95 /**
96 * @see javax.servlet.GenericServlet#init()
97 */
98 @Override
99 public void init() throws ServletException
100 {
101 try
102 {
103 WebSocketPolicy policy = new WebSocketPolicy(WebSocketBehavior.SERVER);
104
105 String max = getInitParameter("maxIdleTime");
106 if (max != null)
107 {
108 policy.setIdleTimeout(Long.parseLong(max));
109 }
110
111 max = getInitParameter("maxTextMessageSize");
112 if (max != null)
113 {
114 policy.setMaxTextMessageSize(Integer.parseInt(max));
115 }
116
117 max = getInitParameter("maxBinaryMessageSize");
118 if (max != null)
119 {
120 policy.setMaxBinaryMessageSize(Integer.parseInt(max));
121 }
122
123 max = getInitParameter("inputBufferSize");
124 if (max != null)
125 {
126 policy.setInputBufferSize(Integer.parseInt(max));
127 }
128
129 factory = WebSocketServletFactory.Loader.create(policy);
130
131 configure(factory);
132
133 factory.init();
134 }
135 catch (Exception x)
136 {
137 throw new ServletException(x);
138 }
139 }
140
141 /**
142 * @see javax.servlet.http.HttpServlet#service(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
143 */
144 @Override
145 protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
146 {
147 if (factory.isUpgradeRequest(request,response))
148 {
149 // We have an upgrade request
150 if (factory.acceptWebSocket(request,response))
151 {
152 // We have a socket instance created
153 return;
154 }
155 // If we reach this point, it means we had an incoming request to upgrade
156 // but it was either not a proper websocket upgrade, or it was possibly rejected
157 // due to incoming request constraints (controlled by WebSocketCreator)
158 if (response.isCommitted())
159 {
160 // not much we can do at this point.
161 return;
162 }
163 }
164
165 // All other processing
166 super.service(request,response);
167 }
168 }