    001/* ===========================================================
    002 * JFreeChart : a free chart library for the Java(tm) platform
    003 * ===========================================================
    004 *
    005 * (C) Copyright 2000-2011, by Object Refinery Limited and Contributors.
    006 *
    007 * Project Info:  http://www.jfree.org/jfreechart/index.html
    008 *
    009 * This library is free software; you can redistribute it and/or modify it
    010 * under the terms of the GNU Lesser General Public License as published by
    011 * the Free Software Foundation; either version 2.1 of the License, or
    012 * (at your option) any later version.
    013 *
    014 * This library is distributed in the hope that it will be useful, but
    015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
    017 * License for more details.
    018 *
    019 * You should have received a copy of the GNU Lesser General Public
    020 * License along with this library; if not, write to the Free Software
    021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
    022 * USA.
    023 *
    024 * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
    025 * Other names may be trademarks of their respective owners.]
    026 *
    027 * ---------------------
    028 * EntityCollection.java
    029 * ---------------------
    030 * (C) Copyright 2002-2008, by Object Refinery Limited.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   -;
    034 *
    035 * Changes
    036 * -------
    037 * 23-May-2002 : Version 1 (DG);
    038 * 25-Jun-2002 : Removed unnecessary import (DG);
    039 * 26-Jun-2002 : Added iterator() method (DG);
    040 * 03-Oct-2002 : Fixed errors reported by Checkstyle (DG);
    041 * 30-Jan-2004 : Added a method to add a collection of entities.
    042 * 11-Jan-2005 : Removed deprecated code in preparation for the 1.0.0
    043 *               release (DG);
    044 * 18-Jan-2005 : Added getEntity() and getEntityCount() methods (DG);
    045 *
    046 */
    047
    048package org.jfree.chart.entity;
    049
    050import java.util.Collection;
    051import java.util.Iterator;
    052
    053/**
    054 * This interface defines the methods used to access an ordered list of
    055 * {@link ChartEntity} objects.
    056 */
    057public interface EntityCollection {
    058
    059    /**
    060     * Clears all entities.
    061     */
    062    public void clear();
    063
    064    /**
    065     * Adds an entity to the collection.
    066     *
    067     * @param entity  the entity (<code>null</code> not permitted).
    068     */
    069    public void add(ChartEntity entity);
    070
    071    /**
    072     * Adds the entities from another collection to this collection.
    073     *
    074     * @param collection  the other collection.
    075     */
    076    public void addAll(EntityCollection collection);
    077
    078    /**
    079     * Returns an entity whose area contains the specified point.
    080     *
    081     * @param x  the x coordinate.
    082     * @param y  the y coordinate.
    083     *
    084     * @return The entity.
    085     */
    086    public ChartEntity getEntity(double x, double y);
    087
    088    /**
    089     * Returns an entity from the collection.
    090     *
    091     * @param index  the index (zero-based).
    092     *
    093     * @return An entity.
    094     */
    095    public ChartEntity getEntity(int index);
    096
    097    /**
    098     * Returns the entity count.
    099     *
    100     * @return The entity count.
    101     */
    102    public int getEntityCount();
    103
    104    /**
    105     * Returns the entities in an unmodifiable collection.
    106     *
    107     * @return The entities.
    108     */
    109    public Collection getEntities();
    110
    111    /**
    112     * Returns an iterator for the entities in the collection.
    113     *
    114     * @return An iterator.
    115     */
    116    public Iterator iterator();
    117
    118}