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 * 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
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package org.apache.commons.configuration.beanutils;

 The default implementation of the BeanFactory interface. 
 This class creates beans of arbitrary types using reflection. Each time the createBean() method is invoked, a new bean instance is created. A default bean class is not supported. 
 An instance of this factory class will be set as the default bean factory for the BeanHelper class. This means that if not bean factory is specified in a BeanDeclaration, this default instance will be used. 
Author:
Commons
Configuration team
Since:
1.3
Version:
$Id: DefaultBeanFactory.java 1208758 2011-11-30 20:38:59Z oheger $/**
 * <p>
 * The default implementation of the {@code BeanFactory} interface.
 * </p>
 * <p>
 * This class creates beans of arbitrary types using reflection. Each time the
 * {@code createBean()} 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 {@link BeanHelper} class. This means that if not bean
 * factory is specified in a {@link BeanDeclaration}, this
 * default instance will be used.
 * </p>
 *
 * @since 1.3
 * @author <a
 * href="http://commons.apache.org/configuration/team-list.html">Commons
 * Configuration team</a>
 * @version $Id: DefaultBeanFactory.java 1208758 2011-11-30 20:38:59Z oheger $
 */
public class DefaultBeanFactory implements BeanFactory
{
    
Stores the default instance of this class. /** 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 createBeanInstance() and initBeanInstance() for creating and initializing the bean. This makes it easier for derived classes that need to change specific functionality of the base class. 
Params:
beanClass – the class of the bean, from which an instance is to be
created
data – the bean declaration object
parameter – an additional parameter (ignored by this implementation)
Throws:
Exception – if an error occurs
Returns:
the new bean instance/**
     * Creates a new bean instance. This implementation delegates to the
     * protected methods {@code createBeanInstance()} and
     * {@code initBeanInstance()} 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
null for this implementation.
Returns:
the default bean class/**
     * 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 createBean(). It uses reflection to create a new instance of the specified class. 
Params:
beanClass – the class of the bean to be created
data – the bean declaration
Throws:
Exception – if an error occurs
Returns:
the new bean instance/**
     * Creates the bean instance. This method is called by
     * {@code createBean()}. 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 createBean(). It calls the initBean() of BeanHelper for performing the initialization. 
Params:
bean – the newly created bean instance
data – the bean declaration object
Throws:
Exception – if an error occurs/**
     * Initializes the newly created bean instance. This method is called by
     * {@code createBean()}. It calls the
     * {@link BeanHelper#initBean(Object, BeanDeclaration) initBean()}
     * of {@link BeanHelper} 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);
    }
}