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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.configuration.beanutils;
19  
20  import java.lang.reflect.Array;
21  import java.util.Collection;
22  import java.util.Iterator;
23  import java.util.List;
24  
25  import org.apache.commons.beanutils.DynaBean;
26  import org.apache.commons.beanutils.DynaClass;
27  import org.apache.commons.configuration.Configuration;
28  import org.apache.commons.configuration.ConfigurationMap;
29  import org.apache.commons.configuration.ConversionException;
30  import org.apache.commons.configuration.SubsetConfiguration;
31  import org.apache.commons.logging.Log;
32  import org.apache.commons.logging.LogFactory;
33  
34  /***
35   * The <tt>ConfigurationDynaBean</tt> dynamically reads and writes
36   * configurations properties from a wrapped configuration-collection
37   * {@link org.apache.commons.configuration.Configuration} instance. It also
38   * implements a {@link java.util.Map} interface so that it can be used in
39   * JSP 2.0 Expression Language expressions.
40   *
41   * <p>The <code>ConfigurationDynaBean</code> maps nested and mapped properties
42   * to the appropriate <code>Configuration</code> subset using the
43   * {@link org.apache.commons.configuration.Configuration#subset}
44   * method. Similarly, indexed properties reference lists of configuration
45   * properties using the
46   * {@link org.apache.commons.configuration.Configuration#getList(String)}
47   * method. Setting an indexed property always throws an exception.</p>
48   *
49   * <p>Note: Some of the methods expect that a dot (&quot;.&quot;) is used as
50   * property delimitor for the wrapped configuration. This is true for most of
51   * the default configurations. Hierarchical configurations, for which a specific
52   * expression engine is set, may cause problems.</p>
53   *
54   * @author <a href="mailto:ricardo.gladwell@btinternet.com">Ricardo Gladwell</a>
55   * @version $Revision: 681804 $, $Date: 2008-08-01 21:58:59 +0200 (Fr, 01 Aug 2008) $
56   * @since 1.0-rc1
57   */
58  public class ConfigurationDynaBean extends ConfigurationMap implements DynaBean
59  {
60      /*** Constant for the property delimiter.*/
61      private static final String PROPERTY_DELIMITER = ".";
62  
63      /*** The logger.*/
64      private static Log log = LogFactory.getLog(ConfigurationDynaBean.class);
65  
66      /***
67       * Creates a new instance of <code>ConfigurationDynaBean</code> and sets
68       * the configuration this bean is associated with.
69       *
70       * @param configuration the configuration
71       */
72      public ConfigurationDynaBean(Configuration configuration)
73      {
74          super(configuration);
75          if (log.isTraceEnabled())
76          {
77              log.trace("ConfigurationDynaBean(" + configuration + ")");
78          }
79      }
80  
81      public void set(String name, Object value)
82      {
83          if (log.isTraceEnabled())
84          {
85              log.trace("set(" + name + "," + value + ")");
86          }
87  
88          if (value == null)
89          {
90              throw new NullPointerException("Error trying to set property to null.");
91          }
92  
93          if (value instanceof Collection)
94          {
95              Collection collection = (Collection) value;
96              Iterator iterator = collection.iterator();
97              while (iterator.hasNext())
98              {
99                  getConfiguration().addProperty(name, iterator.next());
100             }
101         }
102         else if (value.getClass().isArray())
103         {
104             int length = Array.getLength(value);
105             for (int i = 0; i < length; i++)
106             {
107                 getConfiguration().addProperty(name, Array.get(value, i));
108             }
109         }
110         else
111         {
112             getConfiguration().setProperty(name, value);
113         }
114     }
115 
116     public Object get(String name)
117     {
118         if (log.isTraceEnabled())
119         {
120             log.trace("get(" + name + ")");
121         }
122 
123         // get configuration property
124         Object result = getConfiguration().getProperty(name);
125         if (result == null)
126         {
127             // otherwise attempt to create bean from configuration subset
128             Configuration subset = new SubsetConfiguration(getConfiguration(), name, PROPERTY_DELIMITER);
129             if (!subset.isEmpty())
130             {
131                 result = new ConfigurationDynaBean(subset);
132             }
133         }
134 
135         if (log.isDebugEnabled())
136         {
137             log.debug(name + "=[" + result + "]");
138         }
139 
140         if (result == null)
141         {
142             throw new IllegalArgumentException("Property '" + name + "' does not exist.");
143         }
144         return result;
145     }
146 
147     public boolean contains(String name, String key)
148     {
149         Configuration subset = getConfiguration().subset(name);
150         if (subset == null)
151         {
152             throw new IllegalArgumentException("Mapped property '" + name + "' does not exist.");
153         }
154 
155         return subset.containsKey(key);
156     }
157 
158     public Object get(String name, int index)
159     {
160         try
161         {
162             List list = getConfiguration().getList(name);
163             if (list.isEmpty())
164             {
165                 throw new IllegalArgumentException("Indexed property '" + name + "' does not exist.");
166             }
167 
168             return list.get(index);
169         }
170         catch (ConversionException e)
171         {
172             throw new IllegalArgumentException("Property '" + name + "' is not indexed.");
173         }
174     }
175 
176     public Object get(String name, String key)
177     {
178         Configuration subset = getConfiguration().subset(name);
179         if (subset == null)
180         {
181             throw new IllegalArgumentException("Mapped property '" + name + "' does not exist.");
182         }
183 
184         return subset.getProperty(key);
185     }
186 
187     public DynaClass getDynaClass()
188     {
189         return new ConfigurationDynaClass(getConfiguration());
190     }
191 
192     public void remove(String name, String key)
193     {
194         Configuration subset = new SubsetConfiguration(getConfiguration(), name, PROPERTY_DELIMITER);
195         subset.setProperty(key, null);
196     }
197 
198     public void set(String name, int index, Object value)
199     {
200         try
201         {
202             Object property = getConfiguration().getProperty(name);
203 
204             if (property == null)
205             {
206                 throw new IllegalArgumentException("Property '" + name + "' does not exist.");
207             }
208             else if (property instanceof List)
209             {
210                 List list = (List) property;
211                 list.set(index, value);
212                 getConfiguration().setProperty(name, list);
213             }
214             else if (property.getClass().isArray())
215             {
216                 Array.set(property, index, value);
217             }
218             else if (index == 0)
219             {
220                 getConfiguration().setProperty(name, value);
221             }
222             else
223             {
224                 throw new IllegalArgumentException("Property '" + name + "' is not indexed.");
225             }
226         }
227         catch (ConversionException e)
228         {
229             throw new IllegalArgumentException("Property '" + name + "' is not indexed.");
230         }
231     }
232 
233     public void set(String name, String key, Object value)
234     {
235         getConfiguration().setProperty(name + "." + key, value);
236     }
237 }