/*
 * 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.tree;



A specialized node implementation to be used in view configurations.


Some configurations provide a logical view on the nodes of other
configurations. These configurations construct their own hierarchy of nodes
based on the node trees of their source configurations. This special node
class can be used for this purpose. It allows child nodes and attributes to
be added without changing their parent node. So a node can belong to a
hierarchy of nodes of a source configuration, but be also contained in a view
configuration.

Author:
Commons
Configuration team
Version:
$Id: ViewNode.java 1206488 2011-11-26 16:42:41Z oheger $
Since:
1.3/**
 * <p>
 * A specialized node implementation to be used in view configurations.
 * </p>
 * <p>
 * Some configurations provide a logical view on the nodes of other
 * configurations. These configurations construct their own hierarchy of nodes
 * based on the node trees of their source configurations. This special node
 * class can be used for this purpose. It allows child nodes and attributes to
 * be added without changing their parent node. So a node can belong to a
 * hierarchy of nodes of a source configuration, but be also contained in a view
 * configuration.
 * </p>
 *
 * @author <a
 * href="http://commons.apache.org/configuration/team-list.html">Commons
 * Configuration team</a>
 * @version $Id: ViewNode.java 1206488 2011-11-26 16:42:41Z oheger $
 * @since 1.3
 */
public class ViewNode extends DefaultConfigurationNode
{
    
Adds an attribute to this view node. The new attribute's parent node will
be saved.
Params:
attr – the attribute node to be added/**
     * Adds an attribute to this view node. The new attribute's parent node will
     * be saved.
     *
     * @param attr the attribute node to be added
     */
    @Override
    public void addAttribute(ConfigurationNode attr)
    {
        ConfigurationNode parent = null;

        if (attr != null)
        {
            parent = attr.getParentNode();
            super.addAttribute(attr);
            attr.setParentNode(parent);
        }
        else
        {
            throw new IllegalArgumentException("Attribute node must not be null!");
        }
    }

    
Adds a child node to this view node. The new child's parent node will be
saved.
Params:
child – the child node to be added/**
     * Adds a child node to this view node. The new child's parent node will be
     * saved.
     *
     * @param child the child node to be added
     */
    @Override
    public void addChild(ConfigurationNode child)
    {
        ConfigurationNode parent = null;

        if (child != null)
        {
            parent = child.getParentNode();
            super.addChild(child);
            child.setParentNode(parent);
        }
        else
        {
            throw new IllegalArgumentException("Child node must not be null!");
        }
    }

    
Adds all attribute nodes of the given source node to this view node.
Params:
source – the source node/**
     * Adds all attribute nodes of the given source node to this view node.
     *
     * @param source the source node
     */
    public void appendAttributes(ConfigurationNode source)
    {
        if (source != null)
        {
            for (ConfigurationNode attr : source.getAttributes())
            {
                addAttribute(attr);
            }
        }
    }

    
Adds all child nodes of the given source node to this view node.
Params:
source – the source node/**
     * Adds all child nodes of the given source node to this view node.
     *
     * @param source the source node
     */
    public void appendChildren(ConfigurationNode source)
    {
        if (source != null)
        {
            for (ConfigurationNode child : source.getChildren())
            {
                addChild(child);
            }
        }
    }
}