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Java > Open Source Codes > com > Yasna > forum > tags > NewMessagesTag


1 /**
2  * Copyright (C) 2001 Yasna.com. All rights reserved.
3  *
4  * ===================================================================
5  * The Apache Software License, Version 1.1
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  * notice, this list of conditions and the following disclaimer.
13  *
14  * 2. Redistributions in binary form must reproduce the above copyright
15  * notice, this list of conditions and the following disclaimer in
16  * the documentation and/or other materials provided with the
17  * distribution.
18  *
19  * 3. The end-user documentation included with the redistribution,
20  * if any, must include the following acknowledgment:
21  * "This product includes software developed by
22  * Yasna.com (http://www.yasna.com)."
23  * Alternately, this acknowledgment may appear in the software itself,
24  * if and wherever such third-party acknowledgments normally appear.
25  *
26  * 4. The names "Yazd" and "Yasna.com" must not be used to
27  * endorse or promote products derived from this software without
28  * prior written permission. For written permission, please
29  * contact yazd@yasna.com.
30  *
31  * 5. Products derived from this software may not be called "Yazd",
32  * nor may "Yazd" appear in their name, without prior written
33  * permission of Yasna.com.
34  *
35  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
36  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
37  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
38  * DISCLAIMED. IN NO EVENT SHALL YASNA.COM OR
39  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
42  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
43  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
44  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
45  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
46  * SUCH DAMAGE.
47  * ====================================================================
48  *
49  * This software consists of voluntary contributions made by many
50  * individuals on behalf of Yasna.com. For more information
51  * on Yasna.com, please see <http://www.yasna.com>.
52  */
53
54 /**
55  * Copyright (C) 2000 CoolServlets.com. All rights reserved.
56  *
57  * ===================================================================
58  * The Apache Software License, Version 1.1
59  *
60  * Redistribution and use in source and binary forms, with or without
61  * modification, are permitted provided that the following conditions
62  * are met:
63  *
64  * 1. Redistributions of source code must retain the above copyright
65  * notice, this list of conditions and the following disclaimer.
66  *
67  * 2. Redistributions in binary form must reproduce the above copyright
68  * notice, this list of conditions and the following disclaimer in
69  * the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3. The end-user documentation included with the redistribution,
73  * if any, must include the following acknowledgment:
74  * "This product includes software developed by
75  * CoolServlets.com (http://www.coolservlets.com)."
76  * Alternately, this acknowledgment may appear in the software itself,
77  * if and wherever such third-party acknowledgments normally appear.
78  *
79  * 4. The names "Jive" and "CoolServlets.com" must not be used to
80  * endorse or promote products derived from this software without
81  * prior written permission. For written permission, please
82  * contact webmaster@coolservlets.com.
83  *
84  * 5. Products derived from this software may not be called "Jive",
85  * nor may "Jive" appear in their name, without prior written
86  * permission of CoolServlets.com.
87  *
88  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
89  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
90  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
91  * DISCLAIMED. IN NO EVENT SHALL COOLSERVLETS.COM OR
92  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
93  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
94  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
95  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
96  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
97  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
98  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
99  * SUCH DAMAGE.
100  * ====================================================================
101  *
102  * This software consists of voluntary contributions made by many
103  * individuals on behalf of CoolServlets.com. For more information
104  * on CoolServlets.com, please see <http://www.coolservlets.com>.
105  */
106
107 package com.Yasna.forum.tags;
108
109 import java.io.*;
110 import java.util.*;
111 import javax.servlet.*;
112 import javax.servlet.jsp.*;
113 import javax.servlet.jsp.tagext.*;
114 import javax.servlet.http.*;
115 import com.Yasna.forum.tags.*;
116
117 /**
118  * JSP Tag <b>new_messages</b>, used to test whether a forum,
119  * thread, or message has been modified since the users last
120  * visit to the forum.
121  * <p>
122  * Includes body of tag if there is a new message.
123  * <p>
124  * You can set the optional tag parameter <b>value</b> to <i>true</i> or
125  * <i>false</i>. The body of the tag is included if new_messages matches
126  * the value.
127  * <p>
128  * JSP Tag Lib Descriptor
129  * <p><pre>
130  * &lt;name&gt;new_messages&lt;/name&gt;
131  * &lt;tagclass&gt;com.Yasna.forum.tags.NewMessagesTag&lt;/tagclass&gt;
132  * &lt;bodycontent&gt;JSP&lt;/bodycontent&gt;
133  * &lt;info&gt;Includes body of tag if there are new messages since last forum visit.&lt;/info&gt;
134  * &lt;attribute&gt;
135  * &lt;name&gt;value&lt;/name&gt;
136  * &lt;required&gt;false&lt;/required&gt;
137  * &lt;rtexprvalue&gt;false&lt;/rtexprvalue&gt;
138  * &lt;/attribute&gt;
139  * </pre>
140  *
141  * @author Glenn Nielsen
142  */
143 public class NewMessagesTag extends TagSupport
144 {
145   private Boolean JavaDoc value = null;
146
147   /**
148    * @return EVAL_BODY_INCLUDE if there are new messages, or SKIP_BODY if there are no new messages
149    */
150   public final int doStartTag() throws JspException
151   {
152     boolean result = false;
153     // Get the closest enclosing forum, thread, or message tag.
154 try {
155       NewMessages nm = (NewMessages)this.findAncestorWithClass(this,
156           Class.forName("com.Yasna.forum.tags.NewMessages"));
157       result = nm.newMessages();
158     } catch(Exception JavaDoc e) {
159     }
160
161     if( value == null ) {
162       if( result )
163         return EVAL_BODY_INCLUDE;
164     } else {
165       if( value.booleanValue() == result )
166         return EVAL_BODY_INCLUDE;
167     }
168
169     // There are no errors or result matches value
170 return SKIP_BODY;
171   }
172
173   /**
174    * Set the value of the optional attribute value to "true" or "false".
175    *
176    * @param String "true" or "false"
177    */
178   public void setValue(String JavaDoc str)
179   {
180      value = new Boolean JavaDoc(str);
181   }
182 }
183
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