001/* ========================================================================
002 * JCommon : a free general purpose class library for the Java(tm) platform
003 * ========================================================================
004 *
005 * (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
006 * 
007 * Project Info:  http://www.jfree.org/jcommon/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 * AnnualDateRule.java
029 * -------------------
030 * (C) Copyright 2000-2003, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * $Id: AnnualDateRule.java,v 1.4 2005/11/16 15:58:40 taqua Exp $
036 *
037 * Changes (from 26-Oct-2001)
038 * --------------------------
039 * 26-Oct-2001 : Changed package to com.jrefinery.date.* (DG);
040 * 12-Nov-2001 : Javadoc comments updated (DG);
041 * 03-Oct-2002 : Fixed errors reported by Checkstyle (DG);
042 *
043 */
044
045package org.jfree.date;
046
047/**
048 * The base class for all 'annual' date rules: that is, rules for generating
049 * one date for any given year.
050 * <P>
051 * One example is Easter Sunday (which can be calculated using published algorithms).
052 *
053 * @author David Gilbert
054 */
055public abstract class AnnualDateRule implements Cloneable {
056
057    /**
058     * Default constructor.
059     */
060    protected AnnualDateRule() {
061    }
062
063    /**
064     * Returns the date for this rule, given the year.
065     *
066     * @param year  the year (1900 &lt;= year &lt;= 9999).
067     *
068     * @return the date for this rule, given the year.
069     */
070    public abstract SerialDate getDate(int year);
071
072    /**
073     * Returns a clone of the rule.
074     * <P>
075     * You should refer to the documentation of the clone() method in each
076     * subclass for exact details.
077     *
078     * @return a clone of the rule.
079     *
080     * @throws CloneNotSupportedException if the rule is not clonable.
081     */
082    public Object clone() throws CloneNotSupportedException {
083        return super.clone();
084    }
085
086}