001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-present, by David Gilbert 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 * DateRange.java
029 * --------------
030 * (C) Copyright 2002-present, by David Gilbert and Contributors.
031 *
032 * Original Author:  David Gilbert;
033 * Contributor(s):   Bill Kelemen;
034 *
035 */
036
037package org.jfree.data.time;
038
039import java.io.Serializable;
040import java.text.DateFormat;
041import java.util.Date;
042
043import org.jfree.data.Range;
044
045/**
046 * A range specified in terms of two {@code java.util.Date} objects.
047 * Instances of this class are immutable.
048 */
049public class DateRange extends Range implements Serializable {
050
051    /** For serialization. */
052    private static final long serialVersionUID = -4705682568375418157L;
053
054    /** The lower bound for the range. */
055    private final long lowerDate;
056
057    /** The upper bound for the range. */
058    private final long upperDate;
059
060    /**
061     * Default constructor.
062     */
063    public DateRange() {
064        this(new Date(0), new Date(1));
065    }
066
067    /**
068     * Constructs a new range.
069     *
070     * @param lower  the lower bound ({@code null} not permitted).
071     * @param upper  the upper bound ({@code null} not permitted).
072     */
073    public DateRange(Date lower, Date upper) {
074        super(lower.getTime(), upper.getTime());
075        this.lowerDate = lower.getTime();
076        this.upperDate = upper.getTime();
077    }
078
079    /**
080     * Constructs a new range using two values that will be interpreted as
081     * "milliseconds since midnight GMT, 1-Jan-1970".
082     *
083     * @param lower  the lower (oldest) date.
084     * @param upper  the upper (most recent) date.
085     */
086    public DateRange(double lower, double upper) {
087        super(lower, upper);
088        this.lowerDate = (long) lower;
089        this.upperDate = (long) upper;
090    }
091
092    /**
093     * Constructs a new range that is based on another {@link Range}.  The
094     * other range does not have to be a {@link DateRange}.  If it is not, the
095     * upper and lower bounds are evaluated as milliseconds since midnight
096     * GMT, 1-Jan-1970.
097     *
098     * @param other  the other range ({@code null} not permitted).
099     */
100    public DateRange(Range other) {
101        this(other.getLowerBound(), other.getUpperBound());
102    }
103
104    /**
105     * Returns the lower (earlier) date for the range.
106     *
107     * @return The lower date for the range.
108     *
109     * @see #getLowerMillis()
110     */
111    public Date getLowerDate() {
112        return new Date(this.lowerDate);
113    }
114
115    /**
116     * Returns the lower bound of the range in milliseconds.
117     *
118     * @return The lower bound.
119     *
120     * @see #getLowerDate()
121     */
122    public long getLowerMillis() {
123        return this.lowerDate;
124    }
125
126    /**
127     * Returns the upper (later) date for the range.
128     *
129     * @return The upper date for the range.
130     *
131     * @see #getUpperMillis()
132     */
133    public Date getUpperDate() {
134        return new Date(this.upperDate);
135    }
136
137    /**
138     * Returns the upper bound of the range in milliseconds.
139     *
140     * @return The upper bound.
141     *
142     * @see #getUpperDate()
143     */
144    public long getUpperMillis() {
145        return this.upperDate;
146    }
147
148    /**
149     * Returns a string representing the date range (useful for debugging).
150     *
151     * @return A string representing the date range.
152     */
153    @Override
154    public String toString() {
155        DateFormat df = DateFormat.getDateTimeInstance();
156        return "[" + df.format(getLowerDate()) + " --> "
157                + df.format(getUpperDate()) + "]";
158    }
159
160}