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1
17 package org.apache.activemq.web;
18
19 import org.apache.activemq.ActiveMQConnectionFactory;
20 import org.apache.activemq.util.FactoryFinder;
21 import org.apache.activemq.util.IntrospectionSupport;
22 import org.apache.activemq.web.view.MessageRenderer;
23
24 import javax.jms.Connection  ;
25 import javax.jms.ConnectionFactory ;
26 import javax.jms.JMSException ;
27 import javax.jms.Queue ;
28 import javax.jms.QueueBrowser ;
29 import javax.jms.Session ;
30 import javax.servlet.ServletException ;
31 import javax.servlet.http.HttpServlet ;
32 import javax.servlet.http.HttpServletRequest ;
33 import javax.servlet.http.HttpServletResponse ;
34
35 import java.io.IOException ;
36 import java.util.Enumeration ;
37 import java.util.HashMap ;
38 import java.util.LinkedList ;
39 import java.util.Map ;
40
41
52 public class QueueBrowseServlet extends HttpServlet {
53
54 private static FactoryFinder factoryFinder = new FactoryFinder("META-INF/services/org/apache/activemq/web/view/");
55
56 private ConnectionFactory connectionFactory;
57 private Connection connection;
58 private LinkedList sessions = new LinkedList ();
59
60 public Connection getConnection() throws JMSException {
61 if (connection == null) {
62 connection = getConnectionFactory().createConnection();
63 connection.start();
64 }
65 return connection;
66 }
67
68 public void setConnection(Connection connection) {
69 this.connection = connection;
70 }
71
72 public ConnectionFactory getConnectionFactory() {
73 if (connectionFactory == null) {
74 connectionFactory = new ActiveMQConnectionFactory("vm://localhost");
76 }
77 return connectionFactory;
78 }
79
80 public void setConnectionFactory(ConnectionFactory connectionFactory) {
81 this.connectionFactory = connectionFactory;
82 }
83
84 protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException , IOException {
87 Session session = null;
88 try {
89 session = borrowSession();
90 Queue queue = getQueue(request, session);
91 if (queue == null) {
92 throw new ServletException ("No queue URI specified");
93 }
94 String selector = getSelector(request);
95 QueueBrowser browser = session.createBrowser(queue, selector);
96 MessageRenderer renderer = getMessageRenderer(request);
97 configureRenderer(request, renderer);
98 renderer.renderMessages(request, response, browser);
99 }
100 catch (JMSException e) {
101 throw new ServletException (e);
102 }
103 finally {
104 returnSession(session);
105 }
106 }
107
108 protected MessageRenderer getMessageRenderer(HttpServletRequest request) throws IOException , ServletException {
109 String style = request.getParameter("view");
110 if (style == null) {
111 style = "simple";
112 }
113 try {
114 return (MessageRenderer) factoryFinder.newInstance(style);
115 }
116 catch (IllegalAccessException e) {
117 throw new NoSuchViewStyleException(style, e);
118 }
119 catch (InstantiationException e) {
120 throw new NoSuchViewStyleException(style, e);
121 }
122 catch (ClassNotFoundException e) {
123 throw new NoSuchViewStyleException(style, e);
124 }
125 }
126
127 protected void configureRenderer(HttpServletRequest request, MessageRenderer renderer) {
128 Map properties = new HashMap ();
129 for (Enumeration iter = request.getParameterNames(); iter.hasMoreElements(); ) {
130 String name = (String ) iter.nextElement();
131 properties.put(name, request.getParameter(name));
132 }
133 IntrospectionSupport.setProperties(renderer, properties);
134 }
135
136 protected Session borrowSession() throws JMSException {
137 Session answer = null;
138 synchronized (sessions) {
139 if (sessions.isEmpty()) {
140 answer = createSession();
141 }
142 else {
143 answer = (Session ) sessions.removeLast();
144 }
145 }
146 return answer;
147 }
148
149 protected void returnSession(Session session) {
150 if (session != null) {
151 synchronized (sessions) {
152 sessions.add(session);
153 }
154 }
155 }
156
157 protected Session createSession() throws JMSException {
158 return getConnection().createSession(false, Session.AUTO_ACKNOWLEDGE);
159 }
160
161 protected String getSelector(HttpServletRequest request) {
162 return request.getParameter("selector");
163 }
164
165 protected Queue getQueue(HttpServletRequest request, Session session) throws JMSException {
166 String uri = request.getPathInfo();
167 if (uri == null)
168 return null;
169
170 if (uri.startsWith("/")) {
172 uri = uri.substring(1);
173 if (uri.length() == 0)
174 return null;
175 }
176 uri = uri.replace('/', '.');
177
178 System.out.println("destination uri = " + uri);
179
180 return session.createQueue(uri);
181 }
182
183 }
184 |
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