org.dom4j.bean.BeanMetaData Maven / Gradle / Ivy
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/*
* Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
*
* This software is open source.
* See the bottom of this file for the licence.
*/
package org.dom4j.bean;
import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;
import org.dom4j.DocumentFactory;
import org.dom4j.QName;
/**
*
* BeanMetaData contains metadata about a bean class.
*
*
* @author James Strachan
* @version $Revision: 1.10 $
*/
public class BeanMetaData {
/** Empty arguments for reflection calls */
protected static final Object[] NULL_ARGS = {};
/** Singleton cache */
private static Map, BeanMetaData> singletonCache = new HashMap, BeanMetaData>();
private static final DocumentFactory DOCUMENT_FACTORY = BeanDocumentFactory
.getInstance();
/** Property descriptors for the bean */
private PropertyDescriptor[] propertyDescriptors;
/** QNames for the attributes */
private QName[] qNames;
/** Read methods used for getting properties */
private Method[] readMethods;
/** Write methods used for setting properties */
private Method[] writeMethods;
/** Index of names and QNames to indices
* Keys are type of QName and String
*/
private Map nameMap = new HashMap();
public BeanMetaData(Class beanClass) {
if (beanClass != null) {
try {
BeanInfo beanInfo = Introspector.getBeanInfo(beanClass);
propertyDescriptors = beanInfo.getPropertyDescriptors();
} catch (IntrospectionException e) {
handleException(e);
}
}
if (propertyDescriptors == null) {
propertyDescriptors = new PropertyDescriptor[0];
}
int size = propertyDescriptors.length;
qNames = new QName[size];
readMethods = new Method[size];
writeMethods = new Method[size];
for (int i = 0; i < size; i++) {
PropertyDescriptor propertyDescriptor = propertyDescriptors[i];
String name = propertyDescriptor.getName();
QName qName = DOCUMENT_FACTORY.createQName(name);
qNames[i] = qName;
readMethods[i] = propertyDescriptor.getReadMethod();
writeMethods[i] = propertyDescriptor.getWriteMethod();
nameMap.put(name, i);
nameMap.put(qName, i);
}
}
/**
* Static helper method to find and cache meta data objects for bean types
*
* @param beanClass
* DOCUMENT ME!
*
* @return DOCUMENT ME!
*/
public static BeanMetaData get(Class beanClass) {
BeanMetaData answer = singletonCache.get(beanClass);
if (answer == null) {
answer = new BeanMetaData(beanClass);
singletonCache.put(beanClass, answer);
}
return answer;
}
/**
* DOCUMENT ME!
*
* @return the number of attribtutes for this bean type
*/
public int attributeCount() {
return propertyDescriptors.length;
}
public BeanAttributeList createAttributeList(BeanElement parent) {
return new BeanAttributeList(parent, this);
}
public QName getQName(int index) {
return qNames[index];
}
public int getIndex(String name) {
Integer index = nameMap.get(name);
return (index != null) ? index : (-1);
}
public int getIndex(QName qName) {
Integer index = nameMap.get(qName);
return (index != null) ? index : (-1);
}
public Object getData(int index, Object bean) {
try {
Method method = readMethods[index];
return method.invoke(bean, NULL_ARGS);
} catch (Exception e) {
handleException(e);
return null;
}
}
public void setData(int index, Object bean, Object data) {
try {
Method method = writeMethods[index];
Object[] args = {data};
method.invoke(bean, args);
} catch (Exception e) {
handleException(e);
}
}
// Implementation methods
// -------------------------------------------------------------------------
protected void handleException(Exception e) {
// ignore introspection exceptions
}
}
/*
* Redistribution and use of this software and associated documentation
* ("Software"), with or without modification, are permitted provided that the
* following conditions are met:
*
* 1. Redistributions of source code must retain copyright statements and
* notices. Redistributions must also contain a copy of this document.
*
* 2. 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.
*
* 3. The name "DOM4J" must not be used to endorse or promote products derived
* from this Software without prior written permission of MetaStuff, Ltd. For
* written permission, please contact [email protected].
*
* 4. Products derived from this Software may not be called "DOM4J" nor may
* "DOM4J" appear in their names without prior written permission of MetaStuff,
* Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
*
* 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
*
* THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESSED 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 METASTUFF, LTD. OR ITS 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.
*
* Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
*/