    001    /* ===========================================================
    002     * JFreeChart : a free chart library for the Java(tm) platform
    003     * ===========================================================
    004     *
    005     * (C) Copyright 2000-2007, 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     * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
    025     * in the United States and other countries.]
    026     *
    027     * ---------------------
    028     * EntityCollection.java
    029     * ---------------------
    030     * (C) Copyright 2002-2007, 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
    048    package org.jfree.chart.entity;
    049
    050    import java.util.Collection;
    051    import java.util.Iterator;
    052
    053    /**
    054     * This interface defines the methods used to access an ordered list of
    055     * {@link ChartEntity} objects.
    056     */
    057    public 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    }