/* ===========================================================

 * JFreeChart : a free chart library for the Java(tm) platform

 * ===========================================================

 *

 * (C) Copyright 2000-2004, by Object Refinery Limited and Contributors.

 *

 * Project Info:  http://www.jfree.org/jfreechart/index.html

 *

 * This library is free software; you can redistribute it and/or modify it under the terms

 * of the GNU Lesser General Public License as published by the Free Software Foundation;

 * either version 2.1 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;

 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

 * See the GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License along with this

 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,

 * Boston, MA 02111-1307, USA.

 *

 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 

 * in the United States and other countries.]

 *

 * --------------

 * DateRange.java

 * --------------

 * (C) Copyright 2002-2004, by Object Refinery Limited and Contributors.

 *

 * Original Author:  David Gilbert (for Object Refinery Limited);

 * Contributor(s):   Bill Kelemen;

 *

 * $Id: DateRange.java,v 1.1 2004/08/31 15:34:17 mungady Exp $

 *

 * Changes

 * -------

 * 22-Apr-2002 : Version 1 based on code by Bill Kelemen (DG);

 * 07-Oct-2002 : Fixed errors reported by Checkstyle (DG);

 * 23-Sep-2003 : Minor Javadoc update (DG);

 *

 */



package org.jfree.data.time;



import java.io.Serializable;

import java.text.DateFormat;

import java.util.Date;



import org.jfree.data.Range;



/**

 * A range specified in terms of two <code>java.util.Date</code> objects.  Instances of this class 

 * are immutable.

 */

public class DateRange extends Range implements Serializable {



    /** The lower bound for the range. */

    private Date lowerDate;



    /** The upper bound for the range. */

    private Date upperDate;



    /**

     * Default constructor.

     */

    public DateRange() {

        this(new Date(0), new Date(1));

    }



    /**

     * Constructs a new range.

     *

     * @param lower  the lower bound (<code>null</code> not permitted).

     * @param upper  the upper bound (<code>null</code> not permitted).

     */

    public DateRange(final Date lower, final Date upper) {



        super(lower.getTime(), upper.getTime());

        this.lowerDate = lower;

        this.upperDate = upper;



    }



    /**

     * Constructs a new range using two values that will be interpreted as "milliseconds since

     * midnight GMT, 1-Jan-1970".

     *

     * @param lower  the lower (oldest) date.

     * @param upper  the upper (most recent) date.

     */

    public DateRange(final double lower, final double upper) {



        super(lower, upper);

        this.lowerDate = new Date((long) lower);

        this.upperDate = new Date((long) upper);





    }



    /**

     * Constructs a new range that is based on another {@link Range}.

     * <P>

     * The other range does not have to be a {@link DateRange}.  If it is not, the upper

     * and lower bounds are evaluated as milliseconds since midnight GMT, 1-Jan-1970.

     *

     * @param other  the other range (<code>null</code> not permitted).

     */

    public DateRange(final Range other) {

        this(other.getLowerBound(), other.getUpperBound());

    }



    /**

     * Returns the lower (earlier) date for the range.

     *

     * @return The lower date for the range.

     */

    public Date getLowerDate() {

        return this.lowerDate;

    }



    /**

     * Returns the upper (later) date for the range.

     *

     * @return The upper date for the range.

     */

    public Date getUpperDate() {

        return this.upperDate;

    }

    

    /**

     * Returns a string representing the date range (useful for debugging).

     * 

     * @return A string representing the date range.

     */

    public String toString() {

        final DateFormat df = DateFormat.getDateTimeInstance();

        return "[" + df.format(this.lowerDate) + " --> " + df.format(this.upperDate) + "]";

    }



}

