001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.jxpath;
018    
019    /**
020     * A generic mechanism for accessing collections of name/value pairs.
021     * Examples of such collections are HashMap, Properties,
022     * ServletContext.  In order to add support for a new such collection
023     * type to JXPath, perform the following two steps:
024     * <ol>
025     * <li>Build an implementation of the DynamicPropertyHandler interface
026     * for the desired collection type.</li>
027     * <li>Invoke the static method {@link JXPathIntrospector#registerDynamicClass
028     * JXPathIntrospector.registerDynamicClass(class, handlerClass)}</li>
029     * </ol>
030     * JXPath allows access to dynamic properties using these three formats:
031     * <ul>
032     * <li><code>"myMap/myKey"</code></li>
033     * <li><code>"myMap[@name = 'myKey']"</code></li>
034     * <li><code>"myMap[name(.) = 'myKey']"</code></li>
035     * </ul>
036     *
037     * @author Dmitri Plotnikov
038     * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
039     */
040    public interface DynamicPropertyHandler {
041    
042        /**
043         * Returns a list of dynamic property names for the supplied object.
044         * @param object to inspect
045         * @return String[]
046         */
047        String[] getPropertyNames(Object object);
048    
049        /**
050         * Returns the value of the specified dynamic property.
051         * @param object to search
052         * @param propertyName to retrieve
053         * @return Object
054         */
055        Object getProperty(Object object, String propertyName);
056    
057        /**
058         * Modifies the value of the specified dynamic property.
059         * @param object to modify
060         * @param propertyName to modify
061         * @param value to set
062         */
063        void setProperty(Object object, String propertyName, Object value);
064    }