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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
* limitations under the License.
*/
package org.apache.commons.configuration2.beanutils;
/**
*
* Definition of an interface for bean factories.
*
*
* Beans defined in configuration files are not directly created, but by so
* called bean factories. This additional level of indirection
* provides for high flexibility in the creation process. For instance one
* implementation of this interface could be very simple and create a new
* instance of the specified class for each invocation. A different
* implementation could cache already created beans and ensure that always the
* same bean of the given class will be returned - this would be an easy mean
* for creating singleton objects.
*
*
* The interface itself is quite simple. There is a single method for creating a
* bean of a given class. All necessary parameters are obtained from a
* passed in {@link BeanCreationContext} object. It is also possible
* (but optional) for a bean factory to declare the default class of the bean it
* creates. Then it is not necessary to specify a bean class in the bean
* declaration.
*
*
* @since 1.3
* @author Commons
* Configuration team
* @version $Id: BeanFactory.java 1624601 2014-09-12 18:04:36Z oheger $
*/
public interface BeanFactory
{
/**
* Returns a bean instance for the given context object. All information
* about the bean to be created are contained in the provided
* {@code BeanCreationContext} object. This includes a
* {@link BeanDeclaration} defining the properties of the bean. It is up to
* a concrete implementation how the bean is created and initialized.
*
* @param bcc the context object for the bean to be created
* @return the new bean instance (should not be null)
* @throws Exception if an error occurs (the helper classes for creating
* beans will catch this generic exception and wrap it in a
* configuration exception)
*/
Object createBean(BeanCreationContext bcc) throws Exception;
/**
* Returns the default bean class of this bean factory. If an implementation
* here returns a non null value, bean declarations using this
* factory do not need to provide the name of the bean class. In such a case
* an instance of the default class will be created.
*
* @return the default class of this factory or null if there is
* none
*/
Class getDefaultBeanClass();
}