    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 * DateRange.java
    029 * --------------
    030 * (C) Copyright 2002-2008, by Object Refinery Limited and Contributors.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   Bill Kelemen;
    034 *
    035 * Changes
    036 * -------
    037 * 22-Apr-2002 : Version 1 based on code by Bill Kelemen (DG);
    038 * 07-Oct-2002 : Fixed errors reported by Checkstyle (DG);
    039 * 23-Sep-2003 : Minor Javadoc update (DG);
    040 * 28-May-2008 : Fixed problem with immutability (DG);
    041 * 01-Sep-2008 : Added getLowerMillis() and getUpperMillis() (DG);
    042 *
    043 */
    044
    045package org.jfree.data.time;
    046
    047import java.io.Serializable;
    048import java.text.DateFormat;
    049import java.util.Date;
    050
    051import org.jfree.data.Range;
    052
    053/**
    054 * A range specified in terms of two <code>java.util.Date</code> objects.
    055 * Instances of this class are immutable.
    056 */
    057public class DateRange extends Range implements Serializable {
    058
    059    /** For serialization. */
    060    private static final long serialVersionUID = -4705682568375418157L;
    061
    062    /** The lower bound for the range. */
    063    private long lowerDate;
    064
    065    /** The upper bound for the range. */
    066    private long upperDate;
    067
    068    /**
    069     * Default constructor.
    070     */
    071    public DateRange() {
    072        this(new Date(0), new Date(1));
    073    }
    074
    075    /**
    076     * Constructs a new range.
    077     *
    078     * @param lower  the lower bound (<code>null</code> not permitted).
    079     * @param upper  the upper bound (<code>null</code> not permitted).
    080     */
    081    public DateRange(Date lower, Date upper) {
    082        super(lower.getTime(), upper.getTime());
    083        this.lowerDate = lower.getTime();
    084        this.upperDate = upper.getTime();
    085    }
    086
    087    /**
    088     * Constructs a new range using two values that will be interpreted as
    089     * "milliseconds since midnight GMT, 1-Jan-1970".
    090     *
    091     * @param lower  the lower (oldest) date.
    092     * @param upper  the upper (most recent) date.
    093     */
    094    public DateRange(double lower, double upper) {
    095        super(lower, upper);
    096        this.lowerDate = (long) lower;
    097        this.upperDate = (long) upper;
    098    }
    099
    100    /**
    101     * Constructs a new range that is based on another {@link Range}.  The
    102     * other range does not have to be a {@link DateRange}.  If it is not, the
    103     * upper and lower bounds are evaluated as milliseconds since midnight
    104     * GMT, 1-Jan-1970.
    105     *
    106     * @param other  the other range (<code>null</code> not permitted).
    107     */
    108    public DateRange(Range other) {
    109        this(other.getLowerBound(), other.getUpperBound());
    110    }
    111
    112    /**
    113     * Returns the lower (earlier) date for the range.
    114     *
    115     * @return The lower date for the range.
    116     *
    117     * @see #getLowerMillis()
    118     */
    119    public Date getLowerDate() {
    120        return new Date(this.lowerDate);
    121    }
    122
    123    /**
    124     * Returns the lower bound of the range in milliseconds.
    125     *
    126     * @return The lower bound.
    127     *
    128     * @see #getLowerDate()
    129     *
    130     * @since 1.0.11
    131     */
    132    public long getLowerMillis() {
    133        return this.lowerDate;
    134    }
    135
    136    /**
    137     * Returns the upper (later) date for the range.
    138     *
    139     * @return The upper date for the range.
    140     *
    141     * @see #getUpperMillis()
    142     */
    143    public Date getUpperDate() {
    144        return new Date(this.upperDate);
    145    }
    146
    147    /**
    148     * Returns the upper bound of the range in milliseconds.
    149     *
    150     * @return The upper bound.
    151     *
    152     * @see #getUpperDate()
    153     *
    154     * @since 1.0.11
    155     */
    156    public long getUpperMillis() {
    157        return this.upperDate;
    158    }
    159
    160    /**
    161     * Returns a string representing the date range (useful for debugging).
    162     *
    163     * @return A string representing the date range.
    164     */
    165    public String toString() {
    166        DateFormat df = DateFormat.getDateTimeInstance();
    167        return "[" + df.format(getLowerDate()) + " --> "
    168                + df.format(getUpperDate()) + "]";
    169    }
    170
    171}