    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 * TimePeriod.java
    029 * ---------------
    030 * (C) Copyright 2003-2008, by Object Refinery Limited and Contributors.
    031 *
    032 * Original Author:  David Gilbert (for Object Refinery Limited);
    033 * Contributor(s):   -;
    034 *
    035 * Changes
    036 * -------
    037 * 10-Jan-2003 : Version 1 (DG);
    038 * 13-Mar-2003 : Moved to com.jrefinery.data.time package (DG);
    039 * 27-Jan-2005 : Implemented Comparable (DG);
    040 *
    041 */
    042
    043package org.jfree.data.time;
    044
    045import java.util.Date;
    046
    047/**
    048 * A period of time measured to millisecond precision using two instances of
    049 * <code>java.util.Date</code>.
    050 */
    051public interface TimePeriod extends Comparable {
    052
    053    /**
    054     * Returns the start date/time.  This will always be on or before the
    055     * end date.
    056     *
    057     * @return The start date/time (never <code>null</code>).
    058     */
    059    public Date getStart();
    060
    061    /**
    062     * Returns the end date/time.  This will always be on or after the
    063     * start date.
    064     *
    065     * @return The end date/time (never <code>null</code>).
    066     */
    067    public Date getEnd();
    068
    069}