//--------------------------------------------------------------------------
// Copyright (c) 1998-2004, Drew Davidson and Luke Blanshard
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
// Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// Neither the name of the Drew Davidson nor the names of its contributors
// may be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
// OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
// AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
// DAMAGE.
//--------------------------------------------------------------------------
package org.apache.ibatis.ognl;
import java.beans.IntrospectionException;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
/**
* <p>PropertyDescriptor subclass that describes an indexed set of read/write
* methods to get a property. Unlike IndexedPropertyDescriptor this allows
* the "key" to be an arbitrary object rather than just an int. Consequently
* it does not have a "readMethod" or "writeMethod" because it only expects
* a pattern like:</p>
* <pre>
* public void set<i>Property</i>(<i>KeyType</i>, <i>ValueType</i>);
* public <i>ValueType</i> get<i>Property</i>(<i>KeyType</i>);
* </pre>
* <p>and does not require the methods that access it as an array. OGNL can
* get away with this without losing functionality because if the object
* does expose the properties they are most probably in a Map and that case
* is handled by the normal OGNL property accessors.
* </p>
* <p>For example, if an object were to have methods that accessed and "attributes"
* property it would be natural to index them by String rather than by integer
* and expose the attributes as a map with a different property name:
* <pre>
* public void setAttribute(String name, Object value);
* public Object getAttribute(String name);
* public Map getAttributes();
* </pre>
* <p>Note that the index get/set is called get/set <code>Attribute</code>
* whereas the collection getter is called <code>Attributes</code>. This
* case is handled unambiguously by the OGNL property accessors because the
* set/get<code>Attribute</code> methods are detected by this object and the
* "attributes" case is handled by the <code>MapPropertyAccessor</code>.
* Therefore OGNL expressions calling this code would be handled in the
* following way:
* </p>
* <table>
* <tr><th>OGNL Expression</th>
* <th>Handling</th>
* </tr>
* <tr>
* <td><code>attribute["name"]</code></td>
* <td>Handled by an index getter, like <code>getAttribute(String)</code>.</td>
* </tr>
* <tr>
* <td><code>attribute["name"] = value</code></td>
* <td>Handled by an index setter, like <code>setAttribute(String, Object)</code>.</td>
* </tr>
* <tr>
* <td><code>attributes["name"]</code></td>
* <td>Handled by <code>MapPropertyAccessor</code> via a <code>Map.get()</code>. This
* will <b>not</b> go through the index get accessor.
* </td>
* </tr>
* <tr>
* <td><code>attributes["name"] = value</code></td>
* <td>Handled by <code>MapPropertyAccessor</code> via a <code>Map.put()</code>. This
* will <b>not</b> go through the index set accessor.
* </td>
* </tr>
* </table>
*
* @author Luke Blanshard ([email protected])
* @author Drew Davidson ([email protected])
*/
public class ObjectIndexedPropertyDescriptor extends PropertyDescriptor {
private Method indexedReadMethod;
private Method indexedWriteMethod;
private Class propertyType;
public ObjectIndexedPropertyDescriptor(String propertyName, Class propertyType, Method indexedReadMethod, Method indexedWriteMethod) throws IntrospectionException {
super(propertyName, null, null);
this.propertyType = propertyType;
this.indexedReadMethod = indexedReadMethod;
this.indexedWriteMethod = indexedWriteMethod;
}
public Method getIndexedReadMethod() {
return indexedReadMethod;
}
public Method getIndexedWriteMethod() {
return indexedWriteMethod;
}
public Class getPropertyType() {
return propertyType;
}
}
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