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1 package org.appfuse.webapp.listener;
2
3 import java.util.HashSet  ;
4 import java.util.Set ;
5
6 import javax.servlet.ServletContext ;
7 import javax.servlet.ServletContextEvent ;
8 import javax.servlet.ServletContextListener ;
9 import javax.servlet.http.HttpSessionAttributeListener ;
10 import javax.servlet.http.HttpSessionBindingEvent ;
11
12 import org.acegisecurity.context.HttpSessionContextIntegrationFilter;
13 import org.acegisecurity.context.SecurityContext;
14 import org.acegisecurity.context.SecurityContextHolder;
15 import org.acegisecurity.Authentication;
16 import org.acegisecurity.AuthenticationTrustResolver;
17 import org.acegisecurity.AuthenticationTrustResolverImpl;
18 import org.apache.commons.logging.Log;
19 import org.apache.commons.logging.LogFactory;
20 import org.appfuse.model.User;
21
22
23
31 public class UserCounterListener implements ServletContextListener , HttpSessionAttributeListener {
32 public static final String COUNT_KEY = "userCounter";
33 public static final String USERS_KEY = "userNames";
34 public static final String EVENT_KEY = HttpSessionContextIntegrationFilter.ACEGI_SECURITY_CONTEXT_KEY;
35 private final transient Log log = LogFactory.getLog(UserCounterListener.class);
36 private transient ServletContext servletContext;
37 private int counter;
38 private Set users;
39
40 public synchronized void contextInitialized(ServletContextEvent sce) {
41 servletContext = sce.getServletContext();
42 servletContext.setAttribute((COUNT_KEY), Integer.toString(counter));
43 }
44
45 public synchronized void contextDestroyed(ServletContextEvent event) {
46 servletContext = null;
47 users = null;
48 counter = 0;
49 }
50
51 synchronized void incrementUserCounter() {
52 counter =
53 Integer.parseInt((String ) servletContext.getAttribute(COUNT_KEY));
54 counter++;
55 servletContext.setAttribute(COUNT_KEY, Integer.toString(counter));
56
57 if (log.isDebugEnabled()) {
58 log.debug("User Count: " + counter);
59 }
60 }
61
62 synchronized void decrementUserCounter() {
63 int counter =
64 Integer.parseInt((String ) servletContext.getAttribute(COUNT_KEY));
65 counter--;
66
67 if (counter < 0) {
68 counter = 0;
69 }
70
71 servletContext.setAttribute(COUNT_KEY, Integer.toString(counter));
72
73 if (log.isDebugEnabled()) {
74 log.debug("User Count: " + counter);
75 }
76 }
77
78 synchronized void addUsername(Object user) {
79 users = (Set ) servletContext.getAttribute(USERS_KEY);
80
81 if (users == null) {
82 users = new HashSet ();
83 }
84
85 if (log.isDebugEnabled()) {
86 if (users.contains(user)) {
87 log.debug("User already logged in, adding anyway...");
88 }
89 }
90
91 users.add(user);
92 servletContext.setAttribute(USERS_KEY, users);
93 incrementUserCounter();
94 }
95
96 synchronized void removeUsername(Object user) {
97 users = (Set ) servletContext.getAttribute(USERS_KEY);
98
99 if (users != null) {
100 users.remove(user);
101 }
102
103 servletContext.setAttribute(USERS_KEY, users);
104 decrementUserCounter();
105 }
106
107
111 public void attributeAdded(HttpSessionBindingEvent event) {
112 log.debug("event.name: " + event.getName());
113 if (event.getName().equals(EVENT_KEY) && !isAnonymous()) {
114 SecurityContext securityContext = (SecurityContext) event.getValue();
115 User user = (User) securityContext.getAuthentication().getPrincipal();
116 addUsername(user);
117 }
118 }
119
120 private boolean isAnonymous() {
121 AuthenticationTrustResolver resolver = new AuthenticationTrustResolverImpl();
122 SecurityContext ctx = SecurityContextHolder.getContext();
123 if (ctx != null) {
124 Authentication auth = ctx.getAuthentication();
125 return resolver.isAnonymous(auth);
126 }
127 return true;
128 }
129
130
134 public void attributeRemoved(HttpSessionBindingEvent event) {
135 if (event.getName().equals(EVENT_KEY) && !isAnonymous()) {
136 SecurityContext securityContext = (SecurityContext) event.getValue();
137 Authentication auth = securityContext.getAuthentication();
138 if (auth != null && (auth.getPrincipal() instanceof User)) {
139 User user = (User) auth.getPrincipal();
140 removeUsername(user);
141 }
142 }
143 }
144
145
150 public void attributeReplaced(HttpSessionBindingEvent event) {
151 if (event.getName().equals(EVENT_KEY) && !isAnonymous()) {
152 SecurityContext securityContext = (SecurityContext) event.getValue();
153 if (securityContext.getAuthentication() != null) {
154 User user = (User) securityContext.getAuthentication().getPrincipal();
155 addUsername(user);
156 }
157 }
158 }
159 }
160 |
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