/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* 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,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.configuration.beanutils;
/**
* <p>
* The default implementation of the <code>BeanFactory</code> interface.
* </p>
* <p>
* This class creates beans of arbitrary types using reflection. Each time the
* <code>createBean()</code> method is invoked, a new bean instance is
* created. A default bean class is not supported.
* </p>
* <p>
* An instance of this factory class will be set as the default bean factory for
* the <code>{@link BeanHelper}</code> class. This means that if not bean
* factory is specified in a <code>{@link BeanDeclaration}</code>, this
* default instance will be used.
* </p>
*
* @since 1.3
* @author Oliver Heger
* @version $Id: DefaultBeanFactory.java 439648 2006-09-02 20:42:10Z oheger $
*/
public class DefaultBeanFactory implements BeanFactory
{
/** Stores the default instance of this class. */
public static final DefaultBeanFactory INSTANCE = new DefaultBeanFactory();
/**
* Creates a new bean instance. This implementation delegates to the
* protected methods <code>createBeanInstance()</code> and
* <code>initBeanInstance()</code> for creating and initializing the bean.
* This makes it easier for derived classes that need to change specific
* functionality of the base class.
*
* @param beanClass the class of the bean, from which an instance is to be
* created
* @param data the bean declaration object
* @param parameter an additional parameter (ignored by this implementation)
* @return the new bean instance
* @throws Exception if an error occurs
*/
public Object createBean(Class beanClass, BeanDeclaration data,
Object parameter) throws Exception
{
Object result = createBeanInstance(beanClass, data);
initBeanInstance(result, data);
return result;
}
/**
* Returns the default bean class used by this factory. This is always
* <b>null</b> for this implementation.
*
* @return the default bean class
*/
public Class getDefaultBeanClass()
{
return null;
}
/**
* Creates the bean instance. This method is called by
* <code>createBean()</code>. It uses reflection to create a new instance
* of the specified class.
*
* @param beanClass the class of the bean to be created
* @param data the bean declaration
* @return the new bean instance
* @throws Exception if an error occurs
*/
protected Object createBeanInstance(Class beanClass, BeanDeclaration data)
throws Exception
{
return beanClass.newInstance();
}
/**
* Initializes the newly created bean instance. This method is called by
* <code>createBean()</code>. It calls the
* <code>{@link BeanHelper#initBean(Object, BeanDeclaration) initBean()}</code>
* of <code>{@link BeanHelper}</code> for performing the initialization.
*
* @param bean the newly created bean instance
* @param data the bean declaration object
* @throws Exception if an error occurs
*/
protected void initBeanInstance(Object bean, BeanDeclaration data)
throws Exception
{
BeanHelper.initBean(bean, data);
}
}
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