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1
2 package com.icesoft.faces.webapp.http.servlet;
3
4
5 import java.io.IOException  ;
6 import java.io.InputStream ;
7 import java.io.Writer ;
8 import java.io.PrintWriter ;
9
10 import java.util.ArrayList ;
11 import java.util.Collection ;
12 import java.util.Set ;
13 import java.util.HashSet ;
14 import java.util.Iterator ;
15
16 import org.apache.catalina.CometEvent;
17 import org.apache.catalina.CometProcessor;
18
19 import org.apache.commons.logging.Log;
20 import org.apache.commons.logging.LogFactory;
21
22 import javax.servlet.ServletException ;
23 import javax.servlet.http.HttpServlet ;
24 import javax.servlet.http.HttpServletRequest ;
25 import javax.servlet.http.HttpServletResponse ;
26
27 import com.icesoft.faces.webapp.http.core.SendUpdatedViews;
28 import com.icesoft.faces.webapp.http.core.ViewQueue;
29
30
31 public class TomcatPushServlet
32 extends HttpServlet implements CometProcessor {
33
34 private static Log log = LogFactory.getLog(TomcatPushServlet.class);
35
36 public void init() throws ServletException {
37 }
38
39 public void destroy() {
40 }
41
42
49 public void event(CometEvent event)
50 throws IOException , ServletException {
51
52 HttpServletRequest request = event.getHttpServletRequest();
53 HttpServletResponse response = event.getHttpServletResponse();
54
55 if (event.getEventType() == CometEvent.EventType.BEGIN) {
56 begin(event, request, response);
57 } else if (event.getEventType() == CometEvent.EventType.ERROR) {
58 error(event, request, response);
59 } else if (event.getEventType() == CometEvent.EventType.END) {
60 end(event, request, response);
61 } else if (event.getEventType() == CometEvent.EventType.READ) {
62 read(event, request, response);
63 }
64 }
65
66 protected void begin(CometEvent event, HttpServletRequest request, HttpServletResponse response)
67 throws IOException , ServletException {
68 MainSessionBoundServlet mainBound = (MainSessionBoundServlet)
71 SessionDispatcher.getSingletonSessionServlet(request.getSession());
72 ViewQueue allUpdatedViews = mainBound.getAllUpdatedViews();
73 Collection synchronouslyUpdatedViews =
74 mainBound.getSynchronouslyUpdatedViews();
75 allUpdatedViews.onPut( new EventResponder(
76 event, synchronouslyUpdatedViews, allUpdatedViews) );
77 }
78
79 protected void end(CometEvent event, HttpServletRequest request, HttpServletResponse response)
80 throws IOException , ServletException {
81 event.close();
82 }
83
84 protected void error(CometEvent event, HttpServletRequest request, HttpServletResponse response)
85 throws IOException , ServletException {
86 }
87
88 protected void read(CometEvent event, HttpServletRequest request, HttpServletResponse response)
89 throws IOException , ServletException {
90 InputStream is = request.getInputStream();
91 byte[] buf = new byte[512];
92 do {
93 int n = is.read(buf); if (n > 0) {
95 if (log.isDebugEnabled()) {
96 log.debug( "Read " + n + " bytes: "
97 + new String (buf, 0, n) + " for session: "
98 + request.getSession(true).getId() );
99 }
100 } else if (n < 0) {
101 error(event, request, response);
102 return;
103 }
104 } while (is.available() > 0);
105 }
106
107 protected void service(HttpServletRequest request, HttpServletResponse response)
108 throws IOException , ServletException {
109 throw new ServletException ("service() not supported by TomcatPushServlet");
111 }
112
113
114 }
115
116
117 class EventResponder implements Runnable {
118 ViewQueue allUpdatedViews;
119 Collection synchronouslyUpdatedViews;
120 CometEvent event;
121 Writer writer;
122
123 public EventResponder(CometEvent event,
124 Collection synchronouslyUpdatedViews,
125 ViewQueue allUpdatedViews) {
126 this.event = event;
127 this.synchronouslyUpdatedViews = synchronouslyUpdatedViews;
128 this.allUpdatedViews = allUpdatedViews;
129 try {
130 HttpServletResponse response = event.getHttpServletResponse();
131 writer = response.getWriter();
132 response.setContentType("text/xml;charset=UTF-8");
133 } catch (IOException e) {
134 e.printStackTrace();
135 }
136 }
137
138 public void run() {
139 try {
140 allUpdatedViews.removeAll(synchronouslyUpdatedViews);
141 synchronouslyUpdatedViews.clear();
142 Set viewIdentifiers = new HashSet (allUpdatedViews);
143 if (!viewIdentifiers.isEmpty()) {
144 Iterator identifiers = viewIdentifiers.iterator();
145 writer.write("<updated-views>");
146 while (identifiers.hasNext()) {
147 writer.write(identifiers.next().toString());
148 writer.write(' ');
149 }
150 writer.write("</updated-views>");
151 event.close();
152 }
153 } catch (Throwable e) {
154 e.printStackTrace();
155 }
156 }
157
158 }
159 |
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