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1   /*
2    * Copyright 2002,2004 The Apache Software Foundation.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package org.apache.commons.jelly.tags.jms;
17  
18  import javax.jms.Destination;
19  import javax.jms.Message;
20  import javax.jms.JMSException;
21  
22  import org.apache.commons.jelly.JellyTagException;
23  import org.apache.commons.jelly.TagSupport;
24  import org.apache.commons.jelly.XMLOutput;
25  
26  import org.apache.commons.messenger.Messenger;
27  
28  /*** A tag which creates a JMS message
29    *
30    * @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
31    * @version $Revision: 155420 $
32    */
33  public class MessageTag extends TagSupport {
34  
35      /*** The name of the Message variable that is created */
36      private String var;
37  
38      /*** The JMS Message created */
39      private Message message;
40  
41      /*** The Messenger used to access the JMS connection */
42      private Messenger connection;
43  
44      public MessageTag() {
45      }
46  
47      /*** Adds a JMS property to the message */
48      public void addProperty(String name, Object value) throws JellyTagException {
49          Message message = getMessage();
50  
51          try {
52              message.setObjectProperty(name, value);
53          } catch (JMSException e) {
54              throw new JellyTagException(e);
55          }
56      }
57  
58      // Tag interface
59      //-------------------------------------------------------------------------
60      public void doTag(XMLOutput output) throws JellyTagException {
61          if ( var == null ) {
62              // expose message to parent message consumer
63              SendTag tag = (SendTag) findAncestorWithClass( SendTag.class );
64              if ( tag == null ) {
65                  throw new JellyTagException("<jms:message> tags must either have the 'var' attribute specified or be used inside a <jms:send> tag");
66              }
67  
68              tag.setMessage( getMessage() );
69          }
70          else {
71  
72              context.setVariable( var, getMessage() );
73  
74          }
75      }
76  
77      // Properties
78      //-------------------------------------------------------------------------
79  
80      /*** Sets the name of the variable that the message will be exported to */
81      public void setVar(String var) {
82          this.var = var;
83      }
84  
85      public Messenger getConnection() throws JellyTagException {
86          if ( connection == null ) {
87              return findConnection();
88          }
89          return connection;
90      }
91  
92      /***
93       * Sets the Messenger (the JMS connection pool) that will be used to send the message
94       */
95      public void setConnection(Messenger connection) {
96          this.connection = connection;
97      }
98  
99      public Message getMessage() throws JellyTagException {
100         if ( message == null ) {
101             message = createMessage();
102         }
103         return message;
104     }
105 
106 
107     // JMS related properties
108 
109     /***
110      * Sets the JMS Correlation ID to be used on the message
111      */
112     public void setCorrelationID(String correlationID) throws JellyTagException {
113         try {
114             getMessage().setJMSCorrelationID(correlationID);
115         }
116         catch (JMSException e) {
117             throw new JellyTagException(e);
118         }
119     }
120 
121     /***
122      * Sets the reply-to destination to add to the message
123      */
124     public void setReplyTo(Destination destination) throws JellyTagException {
125         try {
126             getMessage().setJMSReplyTo(destination);
127         }
128         catch (JMSException e) {
129             throw new JellyTagException(e);
130         }
131     }
132 
133     /***
134      * Sets the type name of the message
135      */
136     public void setType(String type) throws JellyTagException {
137         try {
138             getMessage().setJMSType(type);
139         }
140         catch (JMSException e) {
141             throw new JellyTagException(e);
142         }
143     }
144 
145     // Implementation methods
146     //-------------------------------------------------------------------------
147     protected Messenger findConnection() throws JellyTagException {
148         ConnectionContext messengerTag = (ConnectionContext) findAncestorWithClass( ConnectionContext.class );
149         if ( messengerTag == null ) {
150             throw new JellyTagException("This tag must be within a <jms:connection> tag or the 'connection' attribute should be specified");
151         }
152 
153         try {
154             return messengerTag.getConnection();
155         }
156         catch (JMSException e) {
157             throw new JellyTagException(e);
158         }
159     }
160 
161     protected Message createMessage() throws JellyTagException {
162         try {
163             return getConnection().createMessage();
164         } catch (JMSException e) {
165             throw new JellyTagException(e);
166         }
167     }
168 }