package de.lmu.ifi.dbs.elki.result;

/*
 This file is part of ELKI:
 Environment for Developing KDD-Applications Supported by Index-Structures

 Copyright (C) 2015
 Ludwig-Maximilians-Universität München
 Lehr- und Forschungseinheit für Datenbanksysteme
 ELKI Development Team

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Affero General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.EventListener;

/**
 * Listener interface invoked when new results are added to the result tree.
 * 
 * @author Erich Schubert
 * @since 0.4.0
 * 
 * @apiviz.has Result
 */
public interface ResultListener extends EventListener {
  /**
   * A new derived result was added.
   * 
   * @param child New child result added
   * @param parent Parent result that was added to
   */
  public void resultAdded(Result child, Result parent);
  
  /**
   * Notify that the current result has changed substantially.
   * 
   * @param current Result that has changed.
   */
  public void resultChanged(Result current);
  
  /**
   * A result was removed.
   * 
   * @param child result that was removed
   * @param parent Parent result that was removed from
   */
  public void resultRemoved(Result child, Result parent);
}