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1   /*
2    * $Header: /usr/local/cvsroot/dev/madcache/src/com/macvu/tiles/xmlDefinition/XmlCacheDefinition.java,v 1.2 2004/05/06 02:18:54 macvu Exp $
3    * $Revision: 1.2 $
4    * $Date: 2004/05/06 02:18:54 $
5    *
6    * ====================================================================
7    *
8    * The Apache Software License, Version 1.1
9    *
10   * Copyright (c) 1999-2002 The Apache Software Foundation.  All rights
11   * reserved.
12   *
13   * Redistribution and use in source and binary forms, with or without
14   * modification, are permitted provided that the following conditions
15   * are met:
16   *
17   * 1. Redistributions of source code must retain the above copyright
18   *    notice, this list of conditions and the following disclaimer.
19   *
20   * 2. Redistributions in binary form must reproduce the above copyright
21   *    notice, this list of conditions and the following disclaimer in
22   *    the documentation and/or other materials provided with the
23   *    distribution.
24   *
25   * 3. The end-user documentation included with the redistribution, if
26   *    any, must include the following acknowlegement:
27   *       "This product includes software developed by the
28   *        Apache Software Foundation (http://www.apache.org/)."
29   *    Alternately, this acknowlegement may appear in the software itself,
30   *    if and wherever such third-party acknowlegements normally appear.
31   *
32   * 4. The names "The Jakarta Project", "Struts", and "Apache Software
33   *    Foundation" must not be used to endorse or promote products derived
34   *    from this software without prior written permission. For written
35   *    permission, please contact apache@apache.org.
36   *
37   * 5. Products derived from this software may not be called "Apache"
38   *    nor may "Apache" appear in their names without prior written
39   *    permission of the Apache Group.
40   *
41   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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45   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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47   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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49   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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51   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52   * SUCH DAMAGE.
53   * ====================================================================
54   *
55   * This software consists of voluntary contributions made by many
56   * individuals on behalf of the Apache Software Foundation.  For more
57   * information on the Apache Software Foundation, please see
58   * <http://www.apache.org/>.
59   *
60   */
61  
62  package com.macvu.tiles.xmlDefinition;
63  
64  import com.macvu.tiles.CacheComponentDefinition;
65  import org.apache.commons.logging.Log;
66  import org.apache.commons.logging.LogFactory;
67  import org.apache.struts.tiles.NoSuchDefinitionException;
68  import org.apache.struts.tiles.xmlDefinition.XmlAttribute;
69  
70  import java.util.Iterator;
71  
72  
73  public class XmlCacheDefinition extends CacheComponentDefinition {
74  
75      /***
76       * Commons Logging instance.
77       */
78      protected static Log log = LogFactory.getLog(XmlCacheDefinition.class);
79  
80      /***
81       * Used for resolving inheritance.
82       */
83      private boolean isVisited = false;
84  
85      /***
86       * Constructor.
87       */
88      public XmlCacheDefinition() {
89          super();
90      }
91  
92      /***
93       * Add an attribute to this component.
94       *
95       * @param attribute Attribute to add.
96       */
97      public void addAttribute(XmlAttribute attribute) {
98          putAttribute(attribute.getName(), attribute.getValue());
99      }
100 
101     public void addCacheInformation(XmlCacheInformation info) {
102         super.setCacheInformation(info);
103     }
104 
105     /***
106      * Set isVisited.
107      */
108     public void setIsVisited(boolean isVisited) {
109         this.isVisited = isVisited;
110     }
111 
112     /***
113      * Resolve inheritance.
114      * First, resolve parent's inheritance, then set path to the parent's path.
115      * Also copy attributes setted in parent, and not set in child
116      * If instance doesn't extend anything, do nothing.
117      *
118      * @throws org.apache.struts.tiles.NoSuchDefinitionException
119      *          If an inheritance can not be solved.
120      */
121     public void resolveInheritance(XmlCacheDefinitionSet definitionsSet)
122             throws NoSuchDefinitionException {
123         // Already done, or not needed ?
124         if (isVisited || !isExtending())
125             return;
126 
127         if (log.isDebugEnabled())
128             log.debug("Resolve definition for child name='" + getName()
129                     + "' extends='" + getExtends() + "'.");
130 
131         // Set as visited to avoid endless recurisvity.
132         setIsVisited(true);
133 
134         // Resolve parent before itself.
135         XmlCacheDefinition parent = definitionsSet.getDefinition(getExtends());
136         if (parent == null) { // error
137             String msg = "Error while resolving definition inheritance: child '"
138                     + getName() + "' can't find its ancestor '"
139                     + getExtends() + "'. Please check your description file.";
140             log.error(msg);
141             // to do : find better exception
142             throw new NoSuchDefinitionException(msg);
143         }
144 
145         parent.resolveInheritance(definitionsSet);
146 
147         // Iterate on each parent's attribute and add it if not defined in child.
148         Iterator parentAttributes = parent.getAttributes().keySet().iterator();
149         while (parentAttributes.hasNext()) {
150             String name = (String) parentAttributes.next();
151             if (!getAttributes().containsKey(name))
152                 putAttribute(name, parent.getAttribute(name));
153         }
154         // Set path and role if not setted
155         if (path == null)
156             setPath(parent.getPath());
157         if (role == null)
158             setRole(parent.getRole());
159         if (controller == null) {
160             setController(parent.getController());
161             setControllerType(parent.getControllerType());
162         }
163     }
164 
165     /***
166      * Overload this definition with passed child.
167      * All attributes from child are copied to this definition. Previous attributes with
168      * same name are disguarded.
169      * Special attribute 'path','role' and 'extends' are overloaded if defined in child.
170      *
171      * @param child Child used to overload this definition.
172      */
173     public void overload(XmlCacheDefinition child) {
174         if (child.getPath() != null) {
175             path = child.getPath();
176         }
177         if (child.getExtends() != null) {
178             inherit = child.getExtends();
179         }
180         if (child.getRole() != null) {
181             role = child.getRole();
182         }
183         if (child.getController() != null) {
184             controller = child.getController();
185             controllerType = child.getControllerType();
186         }
187         // put all child attributes in parent.
188         attributes.putAll(child.getAttributes());
189     }
190 
191 }