001 /* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2008, 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 * 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
043 package org.jfree.data.general;
044
045 import java.io.Serializable;
046
047 /**
048 * A class that is used to group datasets (currently not used for any specific
049 * purpose).
050 */
051 public 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 }