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1 package com.icesoft.faces.webapp.http.servlet;
2
3 import org.apache.commons.logging.Log;
4 import org.apache.commons.logging.LogFactory;
5
6 import javax.servlet.ServletContextEvent  ;
7 import javax.servlet.ServletContextListener ;
8 import javax.servlet.ServletException ;
9 import javax.servlet.http.HttpServletRequest ;
10 import javax.servlet.http.HttpServletResponse ;
11 import javax.servlet.http.HttpSession ;
12 import javax.servlet.http.HttpSessionEvent ;
13 import javax.servlet.http.HttpSessionListener ;
14 import java.util.ArrayList ;
15 import java.util.HashMap ;
16 import java.util.Iterator ;
17 import java.util.List ;
18 import java.util.Map ;
19
20 public abstract class SessionDispatcher implements PseudoServlet {
21 private static final Log Log = LogFactory.getLog(SessionDispatcher.class);
23 private final static List SessionDispatchers = new ArrayList ();
24 private Map sessionBoundServers = new HashMap ();
25
26 protected SessionDispatcher() {
27 SessionDispatchers.add(this);
28 }
29
30 public void service(HttpServletRequest request, HttpServletResponse response) throws Exception {
31 HttpSession session = request.getSession(true);
32 if (sessionBoundServers.containsKey(session.getId())) {
34 PseudoServlet server = (PseudoServlet) sessionBoundServers.get(session.getId());
35 server.service(request, response);
36 } else {
37 throw new ServletException ("Session expired");
39 }
40 }
41
42 public void shutdown() {
43 Iterator i = sessionBoundServers.values().iterator();
44 while (i.hasNext()) {
45 PseudoServlet server = (PseudoServlet) i.next();
46 server.shutdown();
47 }
48 }
49
50 private void sessionCreated(HttpSession session) {
51 try {
52 sessionBoundServers.put(session.getId(), this.newServlet(session,Listener.lookupSessionMonitor(session)));
53 } catch (Exception e) {
54 Log.warn(e);
55 throw new RuntimeException (e);
56 } catch (Throwable t) {
57 Log.warn(t);
58 throw new RuntimeException (t);
59 }
60 }
61
62 private void sessionShutdown(HttpSession session) {
63 PseudoServlet server = (PseudoServlet) sessionBoundServers.get(session.getId());
64 server.shutdown();
65 }
66
67 private void sessionDestroyed(HttpSession session) {
68 sessionBoundServers.remove(session.getId());
69 }
70
71 public static PseudoServlet getSingletonSessionServlet(HttpSession session) {
73 return ((SessionDispatcher) SessionDispatchers.get(0))
74 .getSessionServlet(session);
75 }
76
77 public PseudoServlet getSessionServlet(HttpSession session) {
78 return (PseudoServlet) sessionBoundServers.get(session.getId());
79 }
80
81 protected abstract PseudoServlet newServlet(HttpSession session, Listener.Monitor sessionMonitor) throws Exception ;
82
83 public static class Listener implements HttpSessionListener , ServletContextListener {
84 private static Map sessionMonitors = new HashMap ();
85 private boolean run = true;
86
87 public void sessionCreated(HttpSessionEvent event) {
88 HttpSession session = event.getSession();
89 sessionMonitors.put(session, new Monitor(session));
90
91 Iterator i = SessionDispatchers.iterator();
92 while (i.hasNext()) {
93 try {
94 SessionDispatcher sessionDispatcher = (SessionDispatcher) i.next();
95 sessionDispatcher.sessionCreated(session);
96 } catch (Exception e) {
97 new RuntimeException (e);
98 }
99 }
100 }
101
102 public void sessionShutdown(HttpSession session) {
103 Iterator i = SessionDispatchers.iterator();
104 while (i.hasNext()) {
105 try {
106 SessionDispatcher sessionDispatcher = (SessionDispatcher) i.next();
107 sessionDispatcher.sessionShutdown(session);
108 } catch (Exception e) {
109 new RuntimeException (e);
110 }
111 }
112 session.invalidate();
113 }
114
115 public void sessionDestroyed(HttpSessionEvent event) {
116 HttpSession session = event.getSession();
117
118 Iterator i = SessionDispatchers.iterator();
119 while (i.hasNext()) {
120 try {
121 SessionDispatcher sessionDispatcher = (SessionDispatcher) i.next();
122 sessionDispatcher.sessionDestroyed(session);
123 } catch (Exception e) {
124 new RuntimeException (e);
125 }
126 }
127 }
128
129 public void contextInitialized(ServletContextEvent servletContextEvent) {
130 Thread monitor = new Thread ("Session Monitor") {
131 public void run() {
132 while (run) {
133 try {
134 Iterator iterator = new ArrayList (sessionMonitors.values()).iterator();
136 while (iterator.hasNext()) {
137 final Monitor sessionMonitor = (Monitor) iterator.next();
138 sessionMonitor.shutdownIfExpired();
139 }
140
141 Thread.sleep(10000);
142 } catch (InterruptedException e) {
143 }
145 }
146 }
147 };
148 monitor.setDaemon(true);
149 monitor.start();
150 }
151
152 public void contextDestroyed(ServletContextEvent servletContextEvent) {
153 run = false;
154 }
155
156 public static Monitor lookupSessionMonitor(HttpSession session) {
157 return (Monitor) sessionMonitors.get(session);
158 }
159
160 public class Monitor {
161 private HttpSession session;
162 private long lastAccess;
163
164 public Monitor(HttpSession session) {
165 this.session = session;
166 this.lastAccess = session.getLastAccessedTime();
167 }
168
169 public void touchSession() {
170 lastAccess = System.currentTimeMillis();
171 }
172
173 private boolean isExpired() {
174 long elapsedInterval = System.currentTimeMillis() - lastAccess;
175 long maxInterval = session.getMaxInactiveInterval() * 1000;
176 return elapsedInterval + 15000 > maxInterval;
178 }
179
180 private void shutdownIfExpired() {
181 try {
182 if (isExpired()) {
183 sessionMonitors.remove(session);
184 sessionShutdown(session);
185 }
186 } catch (IllegalStateException e) {
187 } catch (Throwable t) {
189 Log.warn("Failed to monitor session expiry", t);
191 }
192 }
193 }
194 }
195 }
196 |
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