https://commons.apache.org/proper/commons-configuration/: Tools to assist in the reading of configuration/preferences files in various formats (The Apache Software Foundation)
  • Konstantin Shaposhnikov (scand.com)
  • Jamie M. Guillemette (TD Bank)
  • Jorge Ferrer ()
  • Gabriele Garuglieri (Infoblu S.p.A)
  • Nicolas De Loof (Cap Gemini)
  • Oliver Kopp
  • Dennis Kieselhorst (IRIAN Deutschland)
  • Raviteja Lokineni
  • Vincent Maurin (glispa GmbH)
  • The Alchemist
  • Pascal Essiembre (Norconex Inc.)
  • Patrick Schmidt
  • Daniel Rall (CollabNet, Inc.)
  • Jason van Zyl (Zenplex)
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  • Henning P. Schmiedehausen (INTERMETA - Gesellschaft fuer Mehrwertdienste mbH)
  • Eric Pugh (upstate.com)
  • Brian E. Dunbar (dunbarconsulting.org)
  • Emmanuel Bourg (Ariane Software)
  • Oliver Heger (Bosch Software Innovations)
  • Jörg Schaible
  • Ralph Goers (Intuit)
  • Gary Gregory (Rocket Software)
  • Claude Warren
  • Rob Tompkins 
/*
 * 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.tree;

import java.util.List;


 An extension of the NodeHandler interface which allows access to so-called references stored for a node.




Some specialized configuration implementations needs to store additional data
for the nodes representing configuration properties. This interface provides
methods for querying this data. For instance, it is possible to query a
reference object stored for a specific node.



 InMemoryNodeModel supports references. It can be queried for a ReferenceNodeHandler which can then be used for dealing with references. 


Since:2.0
/**
 * <p>
 * An extension of the {@link NodeHandler} interface which allows access to
 * so-called <em>references</em> stored for a node.
 * </p>
 * <p>
 * Some specialized configuration implementations needs to store additional data
 * for the nodes representing configuration properties. This interface provides
 * methods for querying this data. For instance, it is possible to query a
 * reference object stored for a specific node.
 * </p>
 * <p>
 * {@link InMemoryNodeModel} supports references. It can be queried for a
 * {@code ReferenceNodeHandler} which can then be used for dealing with
 * references.
 * </p>
 *
 * @since 2.0
 */
public interface ReferenceNodeHandler extends NodeHandler<ImmutableNode>
{
    
Returns the reference object associated with the specified node. If no
reference data is associated with this node, result is null.

Params:
  • node – the node in question
Returns:the reference object for this node or null
/**
     * Returns the reference object associated with the specified node. If no
     * reference data is associated with this node, result is <b>null</b>.
     *
     * @param node the node in question
     * @return the reference object for this node or <b>null</b>
     */
    Object getReference(ImmutableNode node);

    
Returns a list with the reference objects for nodes which have been
removed. Whenever a node associated with a reference object is removed
from the nodes structure managed by the owning model, the reference
object is recorded. This is necessary for instance to free some
resources. With this method all recorded reference objects can be
queried. They are typically returned in the order in which they have been
removed.

Returns:a list with reference objects for nodes removed from the model
/**
     * Returns a list with the reference objects for nodes which have been
     * removed. Whenever a node associated with a reference object is removed
     * from the nodes structure managed by the owning model, the reference
     * object is recorded. This is necessary for instance to free some
     * resources. With this method all recorded reference objects can be
     * queried. They are typically returned in the order in which they have been
     * removed.
     *
     * @return a list with reference objects for nodes removed from the model
     */
    List<Object> removedReferences();
}