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1   /*
2    * Copyright 1999-2004 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.jxpath;
17  
18  /***
19   * A generic mechanism for accessing collections of name/value pairs.
20   * Examples of such collections are HashMap, Properties,
21   * ServletContext.  In order to add support for a new such collection
22   * type to JXPath, perform the following two steps:
23   * <ol>
24   * <li>Build an implementation of the DynamicPropertyHandler interface
25   * for the desired collection type.</li>
26   * <li>Invoke the static method {@link JXPathIntrospector#registerDynamicClass
27   * JXPathIntrospector.registerDynamicClass(class, handlerClass)}</li>
28   * </ol>
29   * JXPath allows access to dynamic properties using these three formats:
30   * <ul>
31   * <li><code>"myMap/myKey"</code></li>
32   * <li><code>"myMap[@name = 'myKey']"</code></li>
33   * <li><code>"myMap[name(.) = 'myKey']"</code></li>
34   * </ul>
35   *
36   * @author Dmitri Plotnikov
37   * @version $Revision: 1.5 $ $Date: 2004/02/29 14:17:42 $
38   */
39  public interface DynamicPropertyHandler {
40  
41      /***
42       * Returns a list of dynamic property names for the supplied object.
43       */
44      String[] getPropertyNames(Object object);
45  
46      /***
47       * Returns the value of the specified dynamic property.
48       */
49      Object getProperty(Object object, String propertyName);
50  
51      /***
52       * Modifies the value of the specified dynamic property.
53       */
54      void setProperty(Object object, String propertyName, Object value);
55  }