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 */
017package org.apache.commons.beanutils;
018
019/**
020 * <p>Decorates a {@link DynaBean} to provide <code>Map</code> behavior.</p>
021 *
022 * <p>The motivation for this implementation is to provide access to {@link DynaBean}
023 *    properties in technologies that are unaware of BeanUtils and {@link DynaBean}s -
024 *    such as the expression languages of JSTL and JSF.</p>
025 *
026 * <p>This can be achieved either by wrapping the {@link DynaBean} prior to
027 *    providing it to the technology to process or by providing a <code>Map</code>
028 *    accessor method on the DynaBean implementation:
029 * </p>
030 *    <pre>
031 *         public Map&lt;String, Object&gt; getMap() {
032 *             return new DynaBeanPropertyMapDecorator(this);
033 *         }</pre>
034 *
035 * <p>This, for example, could be used in JSTL in the following way to access
036 *    a DynaBean's <code>fooProperty</code>:
037 * </p>
038 *    <ul><li><code>${myDynaBean.<strong>map</strong>.fooProperty}</code></li></ul>
039 *
040 * <strong>Usage</strong>
041 *
042 * <p>To decorate a {@link DynaBean} simply instantiate this class with the
043 *    target {@link DynaBean}:</p>
044 *
045 * <ul><li><code>Map&lt;String, Object&gt; fooMap = new DynaBeanPropertyMapDecorator(fooDynaBean);</code></li></ul>
046 *
047 * <p>The above example creates a <strong><em>read only</em></strong> <code>Map</code>.
048 *    To create  a <code>Map</code> which can be modified, construct a
049 *    <code>DynaBeanPropertyMapDecorator</code> with the <strong><em>read only</em></strong>
050 *    attribute set to <code>false</code>:</p>
051 *
052 * <ul><li><code>Map&lt;String, Object&gt; fooMap =
053 *   new DynaBeanPropertyMapDecorator(fooDynaBean, false);</code></li></ul>
054 *
055 * <strong>Limitations</strong>
056 * <p>In this implementation the <code>entrySet()</code>, <code>keySet()</code>
057 *    and <code>values()</code> methods create an <strong><em>unmodifiable</em></strong>
058 *    <code>Set</code> and it does not support the Map's <code>clear()</code>
059 *    and <code>remove()</code> operations.</p>
060 *
061 * @since BeanUtils 1.9.0
062 */
063public class DynaBeanPropertyMapDecorator extends BaseDynaBeanMapDecorator<String> {
064
065    /**
066     * Constructs a read only Map for the specified
067     * {@link DynaBean}.
068     *
069     * @param dynaBean The dyna bean being decorated
070     * @throws IllegalArgumentException if the {@link DynaBean} is null.
071     */
072    public DynaBeanPropertyMapDecorator(final DynaBean dynaBean) {
073        super(dynaBean);
074    }
075
076    /**
077     * Construct a Map for the specified {@link DynaBean}.
078     *
079     * @param dynaBean The dyna bean being decorated
080     * @param readOnly <code>true</code> if the Map is read only
081     * otherwise <code>false</code>
082     * @throws IllegalArgumentException if the {@link DynaBean} is null.
083     */
084    public DynaBeanPropertyMapDecorator(final DynaBean dynaBean, final boolean readOnly) {
085        super(dynaBean, readOnly);
086    }
087
088    @Override
089    protected String convertKey(final String propertyName) {
090        return propertyName;
091    }
092}