DynaBeanPropertyMapDecorator.java

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 * contributor license agreements.  See the NOTICE file distributed with
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 * The ASF licenses this file to You under the Apache License, Version 2.0
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 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
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 * See the License for the specific language governing permissions and
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package org.apache.commons.beanutils2;

/**
 * <p>
 * Decorates a {@link DynaBean} to provide {@code Map} behavior.
 * </p>
 *
 * <p>
 * The motivation for this implementation is to provide access to {@link DynaBean} properties in technologies that are unaware of BeanUtils and
 * {@link DynaBean}s - such as the expression languages of JSTL and JSF.
 * </p>
 *
 * <p>
 * This can be achieved either by wrapping the {@link DynaBean} prior to providing it to the technology to process or by providing a {@code Map} accessor method
 * on the DynaBean implementation:
 * </p>
 *
 * <pre>
 * <code>
 *         public Map&lt;String, Object&gt; getMap() {
 *             return new DynaBeanPropertyMapDecorator(this);
 *         }</code>
 * </pre>
 *
 * <p>
 * This, for example, could be used in JSTL in the following way to access a DynaBean's {@code fooProperty}:
 * </p>
 * <ul>
 * <li>{@code ${myDynaBean.<strong>map</strong>.fooProperty}}</li>
 * </ul>
 *
 * <h2>Usage</h2>
 *
 * <p>
 * To decorate a {@link DynaBean} simply instantiate this class with the target {@link DynaBean}:
 * </p>
 *
 * <ul>
 * <li>{@code Map&lt;String, Object&gt; fooMap = new DynaBeanPropertyMapDecorator(fooDynaBean);}</li>
 * </ul>
 *
 * <p>
 * The above example creates a <strong><em>read only</em></strong> {@code Map}. To create a {@code Map} which can be modified, construct a
 * {@code DynaBeanPropertyMapDecorator} with the <strong><em>read only</em></strong> attribute set to {@code false}:
 * </p>
 *
 * <ul>
 * <li>{@code Map<String, Object> fooMap =
 *   new DynaBeanPropertyMapDecorator(fooDynaBean, false);}</li>
 * </ul>
 *
 * <h2>Limitations</h2>
 * <p>
 * In this implementation the {@code entrySet()</code>, <code>keySet()}
 *    and {@code values()} methods create an <strong><em>unmodifiable</em></strong>
 *    {@code Set</code> and it does not support the Map's <code>clear()} and {@code remove()} operations.
 * </p>
 *
 * @since 1.9.0
 */
public class DynaBeanPropertyMapDecorator extends BaseDynaBeanMapDecorator<String> {

    /**
     * Constructs a read only Map for the specified {@link DynaBean}.
     *
     * @param dynaBean The dyna bean being decorated
     * @throws IllegalArgumentException if the {@link DynaBean} is null.
     */
    public DynaBeanPropertyMapDecorator(final DynaBean dynaBean) {
        super(dynaBean);
    }

    /**
     * Constructs a Map for the specified {@link DynaBean}.
     *
     * @param dynaBean The dyna bean being decorated
     * @param readOnly {@code true} if the Map is read only otherwise {@code false}
     * @throws IllegalArgumentException if the {@link DynaBean} is null.
     */
    public DynaBeanPropertyMapDecorator(final DynaBean dynaBean, final boolean readOnly) {
        super(dynaBean, readOnly);
    }

    @Override
    protected String convertKey(final String propertyName) {
        return propertyName;
    }
}