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     * TimePeriodValue.java
029     * --------------------
030     * (C) Copyright 2003-2008, by Object Refinery Limited.
031     *
032     * Original Author:  David Gilbert (for Object Refinery Limited);
033     * Contributor(s):   -;
034     *
035     * Changes
036     * -------
037     * 22-Apr-2003 : Version 1 (DG);
038     * 03-Oct-2006 : Added null argument check to constructor (DG);
039     * 07-Apr-2008 : Added a toString() override for debugging (DG);
040     *
041     */
042    
043    package org.jfree.data.time;
044    
045    import java.io.Serializable;
046    
047    /**
048     * Represents a time period and an associated value.
049     */
050    public class TimePeriodValue implements Cloneable, Serializable {
051    
052        /** For serialization. */
053        private static final long serialVersionUID = 3390443360845711275L;
054    
055        /** The time period. */
056        private TimePeriod period;
057    
058        /** The value associated with the time period. */
059        private Number value;
060    
061        /**
062         * Constructs a new data item.
063         *
064         * @param period  the time period (<code>null</code> not permitted).
065         * @param value  the value associated with the time period.
066         *
067         * @throws IllegalArgumentException if <code>period</code> is
068         *     <code>null</code>.
069         */
070        public TimePeriodValue(TimePeriod period, Number value) {
071            if (period == null) {
072                throw new IllegalArgumentException("Null 'period' argument.");
073            }
074            this.period = period;
075            this.value = value;
076        }
077    
078        /**
079         * Constructs a new data item.
080         *
081         * @param period  the time period (<code>null</code> not permitted).
082         * @param value  the value associated with the time period.
083         *
084         * @throws IllegalArgumentException if <code>period</code> is
085         *     <code>null</code>.
086         */
087        public TimePeriodValue(TimePeriod period, double value) {
088            this(period, new Double(value));
089        }
090    
091        /**
092         * Returns the time period.
093         *
094         * @return The time period (never <code>null</code>).
095         */
096        public TimePeriod getPeriod() {
097            return this.period;
098        }
099    
100        /**
101         * Returns the value.
102         *
103         * @return The value (possibly <code>null</code>).
104         *
105         * @see #setValue(Number)
106         */
107        public Number getValue() {
108            return this.value;
109        }
110    
111        /**
112         * Sets the value for this data item.
113         *
114         * @param value  the new value (<code>null</code> permitted).
115         *
116         * @see #getValue()
117         */
118        public void setValue(Number value) {
119            this.value = value;
120        }
121    
122        /**
123         * Tests this object for equality with the target object.
124         *
125         * @param obj  the object (<code>null</code> permitted).
126         *
127         * @return A boolean.
128         */
129        public boolean equals(Object obj) {
130            if (this == obj) {
131                return true;
132            }
133            if (!(obj instanceof TimePeriodValue)) {
134                return false;
135            }
136    
137            TimePeriodValue timePeriodValue = (TimePeriodValue) obj;
138    
139            if (this.period != null ? !this.period.equals(timePeriodValue.period)
140                    : timePeriodValue.period != null) {
141                return false;
142            }
143            if (this.value != null ? !this.value.equals(timePeriodValue.value)
144                    : timePeriodValue.value != null) {
145                return false;
146            }
147    
148            return true;
149        }
150    
151        /**
152         * Returns a hash code value for the object.
153         *
154         * @return The hashcode
155         */
156        public int hashCode() {
157            int result;
158            result = (this.period != null ? this.period.hashCode() : 0);
159            result = 29 * result + (this.value != null ? this.value.hashCode() : 0);
160            return result;
161        }
162    
163        /**
164         * Clones the object.
165         * <P>
166         * Note: no need to clone the period or value since they are immutable
167         * classes.
168         *
169         * @return A clone.
170         */
171        public Object clone() {
172            Object clone = null;
173            try {
174                clone = super.clone();
175            }
176            catch (CloneNotSupportedException e) { // won't get here...
177                e.printStackTrace();
178            }
179            return clone;
180        }
181    
182        /**
183         * Returns a string representing this instance, primarily for use in
184         * debugging.
185         *
186         * @return A string.
187         */
188        public String toString() {
189            return "TimePeriodValue[" + getPeriod() + "," + getValue() + "]";
190        }
191    
192    }