/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the "License").  You may not use this file except
 * in compliance with the License.
 *
 * You can obtain a copy of the license at
 * https://jaxp.dev.java.net/CDDLv1.0.html.
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * https://jaxp.dev.java.net/CDDLv1.0.html
 * If applicable add the following below this CDDL HEADER
 * with the fields enclosed by brackets "[]" replaced with
 * your own identifying information: Portions Copyright
 * [year] [name of copyright owner]
 */

/*
 * $Id: XMLGregorianCalendar.java,v 1.7 2006/01/12 18:53:55 ndw Exp $
 * @(#)XMLGregorianCalendar.java	1.28 06/03/23
 *
 * Copyright 2005 Sun Microsystems, Inc. All Rights Reserved.
 */

package javax.xml.datatype;

import javax.xml.namespace.QName;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.TimeZone;
import java.util.GregorianCalendar;

/** 
 * <p>Representation for W3C XML Schema 1.0 date/time datatypes.
 * Specifically, these date/time datatypes are 
 * {@link DatatypeConstants#DATETIME},
 * {@link DatatypeConstants#TIME},
 * {@link DatatypeConstants#DATE},
 * {@link DatatypeConstants#GYEARMONTH},
 * {@link DatatypeConstants#GMONTHDAY},
 * {@link DatatypeConstants#GYEAR},
 * {@link DatatypeConstants#GMONTH}, and
 * {@link DatatypeConstants#GDAY}
 * defined in the XML Namespace
 * <code>"http://www.w3.org/2001/XMLSchema"</code>.
 * These datatypes are normatively defined in 
 * <a href="http://www.w3.org/TR/xmlschema-2/#dateTime">W3C XML Schema 1.0 Part 2, Section 3.2.7-14</a>.</p>
 *
 * <p>The table below defines the mapping between XML Schema 1.0
 * date/time datatype fields and this class' fields. It also summarizes
 * the value constraints for the date and time fields defined in
 * <a href="http://www.w3.org/TR/xmlschema-2/#isoformats">W3C XML Schema 1.0 Part 2, Appendix D,
 * <i>ISO 8601 Date and Time Formats</i></a>.</p>
 *
 * <a name="datetimefieldmapping"/>
 * <table border="2" rules="all" cellpadding="2">
 *   <thead>
 *     <tr>
 *       <th align="center" colspan="3">
 *         Date/Time Datatype Field Mapping Between XML Schema 1.0 and Java Representation
 *       </th>
 *     </tr>
 *   </thead>
 *   <tbody>
 *     <tr>
 *       <th>XML Schema 1.0<br/>
 *           datatype<br/> 
 *            field</th>
 *       <th>Related<br/>XMLGregorianCalendar<br/>Accessor(s)</th>
 *       <th>Value Range</th>
 *     </tr>
 *     <tr>
 *       <td><a name="datetimefield-year"/>year</td>
 *       <td> {@link #getYear()} + {@link #getEon()} or<br/>
 *            {@link #getEonAndYear}
 *       </td>
 *       <td> <code>getYear()</code> is a value between -(10^9-1) to (10^9)-1 
 *            or {@link DatatypeConstants#FIELD_UNDEFINED}.<br/>
 *            {@link #getEon()} is high order year value in billion of years.<br/>
 *            <code>getEon()</code> has values greater than or equal to (10^9) or less than or equal to -(10^9).

 *            A value of null indicates field is undefined.</br>
 *            Given that <a href="http://www.w3.org/2001/05/xmlschema-errata#e2-63">XML Schema 1.0 errata</a> states that the 
year zero
 *            will be a valid lexical value in a future version of XML Schema, 
 *            this class allows the year field to be set to zero. Otherwise,
 *            the year field value is handled exactly as described
 *            in the errata and [ISO-8601-1988]. Note that W3C XML Schema 1.0
 *            validation does not allow for the year field to have a value of zero.
 *            </td>
 *     </tr>
 *     <tr>
 *       <td><a name="datetimefield-month"/>month</td>
 *       <td> {@link #getMonth()} </td>
 *       <td> 1 to 12 or {@link DatatypeConstants#FIELD_UNDEFINED} </td>
 *     </tr>
 *     <tr>
 *       <td><a name="datetimefield-day"/>day</td>
 *       <td> {@link #getDay()} </td>