    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 * DatasetGroup.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 * 07-Oct-2002 : Version 1 (DG);
    038 * 26-Mar-2003 : Implemented Serializable (DG);
    039 * 20-Aug-2003 : Implemented Cloneable (DG);
    040 *
    041 */
    042
    043package org.jfree.data.general;
    044
    045import java.io.Serializable;
    046
    047/**
    048 * A class that is used to group datasets (currently not used for any specific
    049 * purpose).
    050 */
    051public class DatasetGroup implements Cloneable, Serializable {
    052
    053    /** For serialization. */
    054    private static final long serialVersionUID = -3640642179674185688L;
    055
    056    /** The group id. */
    057    private String id;
    058
    059    /**
    060     * Constructs a new group.
    061     */
    062    public DatasetGroup() {
    063        super();
    064        this.id = "NOID";
    065    }
    066
    067    /**
    068     * Creates a new group with the specified id.
    069     *
    070     * @param id  the identification for the group.
    071     */
    072    public DatasetGroup(String id) {
    073        if (id == null) {
    074            throw new IllegalArgumentException("Null 'id' argument.");
    075        }
    076        this.id = id;
    077    }
    078
    079    /**
    080     * Returns the identification string for this group.
    081     *
    082     * @return The identification string.
    083     */
    084    public String getID() {
    085        return this.id;
    086    }
    087
    088    /**
    089     * Clones the group.
    090     *
    091     * @return A clone.
    092     *
    093     * @throws CloneNotSupportedException not by this class.
    094     */
    095    public Object clone() throws CloneNotSupportedException {
    096        return super.clone();
    097    }
    098
    099    /**
    100     * Tests this instance for equality with an arbitrary object.
    101     *
    102     * @param obj  the object (<code>null</code> permitted).
    103     *
    104     * @return A boolean.
    105     */
    106    public boolean equals(Object obj) {
    107        if (obj == this) {
    108            return true;
    109        }
    110        if (!(obj instanceof DatasetGroup)) {
    111            return false;
    112        }
    113        DatasetGroup that = (DatasetGroup) obj;
    114        if (!this.id.equals(that.id)) {
    115            return false;
    116        }
    117        return true;
    118    }
    119
    120}