/*

  * 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;

 import java.util.Map;

 /**

  * <p>

  * Definition of an interface for declaring a bean in a configuration file.

  * </p>

  * <p>

  * Commons Configurations allows to define beans (i.e. simple Java objects) in

  * configuration files, which can be created at runtime. This is especially

  * useful if you program against interfaces and want to define the concrete

  * implementation class is a configuration file.

  * </p>

  * <p>

  * This interface defines methods for retrieving all information about a bean

  * that should be created from a configuration file, e.g. the bean's properties

  * or the factory to use for creating the instance. With different

  * implementations different "layouts" of bean declarations can be

  * supported. For instance if an XML configuration file is used, all features of

  * XML (e.g. attributes, nested elements) can be used to define the bean. In a

  * properties file the declaration format is more limited. The purpose of this

  * interface is to abstract from the concrete declaration format.

  * </p>

  *

  * @since 1.3

  * @author Oliver Heger

  * @version $Id: BeanDeclaration.java 439648 2006-09-02 20:42:10Z oheger $

  */

 public interface BeanDeclaration

 {

     /**

      * Returns the name of the <code>BeanFactory</code> that should be used

      * for creating the bean instance. This can be <b>null</b>, then a default

      * factory will be used.

      *

      * @return the name of the bean factory

      */

     String getBeanFactoryName();

     /**

      * Here an arbitrary object can be returned that will be passed to the bean

      * factory. Its meaning is not further specified. The purpose of this

      * additional parameter is to support a further configuration of the bean

      * factory that can be placed directly at the bean declaration.

      *

      * @return a parameter for the bean factory

      */

     Object getBeanFactoryParameter();

     /**

      * Returns the name of the bean class, from which an instance is to be

      * created. This value must be defined unless a default class is provided

      * for the bean creation operation.

      *

      * @return the name of the bean class

      */

     String getBeanClassName();

     /**

      * Returns a map with properties that should be initialized on the newly

      * created bean. The map's keys are the names of the properties; the

      * corresponding values are the properties' values. The return value can be

      * <b>null</b> if no properties should be set.

      *

      * @return a map with properties to be initialized

      */

     Map getBeanProperties();

     /**

      * Returns a map with declarations for beans that should be set as

      * properties of the newly created bean. This allows for complex

      * initialization szenarios: a bean for a bean that contains complex

      * properties (e.g. other beans) can have nested declarations for defining

      * these complex properties. The returned map's key are the names of the

      * properties to initialze. The values are <code>BeanDeclaration</code>

      * implementations. They will be treated like this declaration (in a

      * recursive manner), and the resulting beans are assigned to the

      * corresponding properties.

      *

      * @return a map with nested bean declarations

      */

     Map getNestedBeanDeclarations();

 }