/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

//$Id: DatatypeFactory.java 884950 2009-11-27 18:46:18Z mrglavas $

package javax.xml.datatype;

import java.math.BigInteger;
import java.math.BigDecimal;
import java.util.GregorianCalendar;

/**
 * <p>Factory that creates new <code>javax.xml.datatype</code> <code>Object</code>s that map XML to/from Java <code>Object</code>s.</p>
 * 
 * <p id="DatatypeFactory.newInstance">{@link #newInstance()} is used to create a new <code>DatatypeFactory</code>.
 * The following implementation resolution mechanisms are used in the following order:</p>
 * <ol>
 *    <li>
 *      If the system property specified by {@link #DATATYPEFACTORY_PROPERTY}, "<code>javax.xml.datatype.DatatypeFactory</code>",
 *      exists, a class with the name of the property's value is instantiated.
 *      Any Exception thrown during the instantiation process is wrapped as a {@link DatatypeConfigurationException}.
 *    </li>
 *    <li>
 *      If the file ${JAVA_HOME}/lib/jaxp.properties exists, it is loaded in a {@link java.util.Properties} <code>Object</code>.
 *      The <code>Properties</code> <code>Object </code> is then queried for the property as documented in the prior step
 *      and processed as documented in the prior step.
 *    </li>
 *    <li>
 *      The services resolution mechanism is used, e.g. <code>META-INF/services/java.xml.datatype.DatatypeFactory</code>.
 *      Any Exception thrown during the instantiation process is wrapped as a {@link DatatypeConfigurationException}.
 *    </li>
 *    <li>
 *      The final mechanism is to attempt to instantiate the <code>Class</code> specified by
 *      {@link #DATATYPEFACTORY_IMPLEMENTATION_CLASS}, "<code>javax.xml.datatype.DatatypeFactoryImpl</code>".
 *      Any Exception thrown during the instantiation process is wrapped as a {@link DatatypeConfigurationException}.
 *    </li>
 * </ol> 
 * 
 * @author <a href="mailto:Joseph.Fialli@Sun.COM">Joseph Fialli</a>
 * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
 * @version $Revision: 884950 $, $Date: 2009-11-27 19:46:18 +0100 (Fri, 27 Nov 2009) $
 * @since 1.5
 */
public abstract class DatatypeFactory {

    /**
     * <p>Default property name as defined in JSR 206: Java(TM) API for XML Processing (JAXP) 1.3.</p>
     * 
     * <p>Default value is <code>javax.xml.datatype.DatatypeFactory</code>.</p>
     */
    public static final String DATATYPEFACTORY_PROPERTY = "javax.xml.datatype.DatatypeFactory";

    /**
     * <p>Default implementation class name as defined in JSR 206: Java(TM) API for XML Processing (JAXP) 1.3.</p>
     * 
     * <p>Default value is <code>org.apache.xerces.jaxp.datatype.DatatypeFactoryImpl</code>.</p>
     */
    public static final String DATATYPEFACTORY_IMPLEMENTATION_CLASS = new String("org.apache.xerces.jaxp.datatype.DatatypeFactoryImpl");

    /**
     * <p>Protected constructor to prevent instantiation outside of package.</p>
     * 
     * <p>Use {@link #newInstance()} to create a <code>DatatypeFactory</code>.</p>
     */
    protected DatatypeFactory() {}

    /**
     * <p>Obtain a new instance of a <code>DatatypeFactory</code>.</p>
     * 
     * <p>The implementation resolution mechanisms are <a href="#DatatypeFactory.newInstance">defined</a> in this
     * <code>Class</code>'s documentation.</p>
     * 
     * @return New instance of a <code>DocumentBuilderFactory</code>
     *
     * @throws DatatypeConfigurationException If the implementation is not
     *   available or cannot be instantiated.
     */
    public static DatatypeFactory newInstance()
        throws DatatypeConfigurationException {
        try {
            return (DatatypeFactory) FactoryFinder.find(
                    /* The default property name according to the JAXP spec */
                    DATATYPEFACTORY_PROPERTY,
                    /* The fallback implementation class name */
                    DATATYPEFACTORY_IMPLEMENTATION_CLASS);
        } 
        catch (FactoryFinder.ConfigurationError e) {
            throw new DatatypeConfigurationException(e.getMessage(), e.getException());
        }
    }
    
    /**
     * @return New instance of a <code>DocumentBuilderFactory</code>
     *
     * @throws DatatypeConfigurationException If the implementation is not
     *   available or cannot be instantiated.
     */
    public static DatatypeFactory newInstance(String factoryClassName,
            ClassLoader classLoader) throws DatatypeConfigurationException {
        if (factoryClassName == null) {
            throw new DatatypeConfigurationException("factoryClassName cannot be null.");
        }
        if (classLoader == null) {
            classLoader = SecuritySupport.getContextClassLoader();
        }
        try {
            return (DatatypeFactory) FactoryFinder.newInstance(factoryClassName, classLoader);
        }
        catch (FactoryFinder.ConfigurationError e) {
            throw new DatatypeConfigurationException(e.getMessage(), e.getException());
        }
    }

    /**
     * <p>Obtain a new instance of a <code>Duration</code>
     * specifying the <code>Duration</code> as its string representation, "PnYnMnDTnHnMnS",
     * as defined in XML Schema 1.0 section 3.2.6.1.</p>
     * 
     * <p>XML Schema Part 2: Datatypes, 3.2.6 duration, defines <code>duration</code> as:</p>
     * <blockquote>
     * duration represents a duration of time.
     * The value space of duration is a six-dimensional space where the coordinates designate the
     * Gregorian year, month, day, hour, minute, and second components defined in Section 5.5.3.2 of [ISO 8601], respectively.
     * These components are ordered in their significance by their order of appearance i.e. as
     * year, month, day, hour, minute, and second. 
     * </blockquote>
     * <p>All six values are set and available from the created {@link Duration}</p>
     * 
     * <p>The XML Schema specification states that values can be of an arbitrary size.
     * Implementations may chose not to or be incapable of supporting arbitrarily large and/or small values.
     * An {@link UnsupportedOperationException} will be thrown with a message indicating implementation limits
     * if implementation capacities are exceeded.</p>
     * 
     * @param lexicalRepresentation <code>String</code> representation of a <code>Duration</code>.
     * 
     * @return New <code>Duration</code> created from parsing the <code>lexicalRepresentation</code>.
     * 
     * @throws IllegalArgumentException If <code>lexicalRepresentation</code> is not a valid representation of a <code>Duration</code>.
     * @throws UnsupportedOperationException If implementation cannot support requested values.
     * @throws NullPointerException if <code>lexicalRepresentation</code> is <code>null</code>.
     */
    public abstract Duration newDuration(final String lexicalRepresentation);

    /**
     * <p>Obtain a new instance of a <code>Duration</code>
     * specifying the <code>Duration</code> as milliseconds.</p>
     * 
     * <p>XML Schema Part 2: Datatypes, 3.2.6 duration, defines <code>duration</code> as:</p>
     * <blockquote>
     * duration represents a duration of time.
     * The value space of duration is a six-dimensional space where the coordinates designate the
     * Gregorian year, month, day, hour, minute, and second components defined in Section 5.5.3.2 of [ISO 8601], respectively.
     * These components are ordered in their significance by their order of appearance i.e. as
     * year, month, day, hour, minute, and second. 
     * </blockquote>
     * <p>All six values are set by computing their values from the specified milliseconds
     * and are available using the <code>get</code> methods of  the created {@link Duration}.
     * The values conform to and are defined by:</p>
     * <ul>
     *   <li>ISO 8601:2000(E) Section 5.5.3.2 Alternative format</li>
     *   <li><a href="http://www.w3.org/TR/xmlschema-2/#isoformats">
     *     W3C XML Schema 1.0 Part 2, Appendix D, ISO 8601 Date and Time Formats</a>
     *   </li>
     *   <li>{@link XMLGregorianCalendar}  Date/Time Datatype Field Mapping Between XML Schema 1.0 and Java Representation</li>
     * </ul>
     * 
     * <p>The default start instance is defined by {@link GregorianCalendar}'s use of the start of the epoch: i.e.,
     * {@link java.util.Calendar#YEAR} = 1970,
     * {@link java.util.Calendar#MONTH} = {@link java.util.Calendar#JANUARY},
     * {@link java.util.Calendar#DATE} = 1, etc.
     * This is important as there are variations in the Gregorian Calendar,
     * e.g. leap years have different days in the month = {@link java.util.Calendar#FEBRUARY}
     * so the result of {@link Duration#getMonths()} and {@link Duration#getDays()} can be influenced.</p> 
     * 
     * @param durationInMilliSeconds Duration in milliseconds to create.
     * 
     * @return New <code>Duration</code> representing <code>durationInMilliSeconds</code>.
     */
    public abstract Duration newDuration(final long durationInMilliSeconds);

    /**
     * <p>Obtain a new instance of a <code>Duration</code>
     * specifying the <code>Duration</code> as isPositive, years, months, days, hours, minutes, seconds.</p>
     * 
     * <p>The XML Schema specification states that values can be of an arbitrary size.
     * Implementations may chose not to or be incapable of supporting arbitrarily large and/or small values.
     * An {@link UnsupportedOperationException} will be thrown with a message indicating implementation limits
     * if implementation capacities are exceeded.</p>
     * 
     * <p>A <code>null</code> value indicates that field is not set.</p>
     * 
     * @param isPositive Set to <code>false</code> to create a negative duration. When the length
     *   of the duration is zero, this parameter will be ignored.
     * @param years of this <code>Duration</code>
     * @param months of this <code>Duration</code>
     * @param days of this <code>Duration</code>
     * @param hours of this <code>Duration</code>
     * @param minutes of this <code>Duration</code>
     * @param seconds of this <code>Duration</code>
     * 
     * @return New <code>Duration</code> created from the specified values.
     * 
     * @throws IllegalArgumentException If values are not a valid representation of a <code>Duration</code>.
     * @throws UnsupportedOperationException If implementation cannot support requested values.
     */
    public abstract Duration newDuration(
            final boolean isPositive,
            final BigInteger years,
            final BigInteger months,
            final BigInteger days,
            final BigInteger hours,
            final BigInteger minutes,
            final BigDecimal seconds);

    /**
     * <p>Obtain a new instance of a <code>Duration</code>
     * specifying the <code>Duration</code> as isPositive, years, months, days, hours, minutes, seconds.</p>
     * 
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param isPositive Set to <code>false</code> to create a negative duration. When the length
     *   of the duration is zero, this parameter will be ignored.
     * @param years of this <code>Duration</code>
     * @param months of this <code>Duration</code>
     * @param days of this <code>Duration</code>
     * @param hours of this <code>Duration</code>
     * @param minutes of this <code>Duration</code>
     * @param seconds of this <code>Duration</code>
     * 
     * @return New <code>Duration</code> created from the specified values.
     * 
     * @throws IllegalArgumentException If values are not a valid representation of a <code>Duration</code>.
     * 
     * @see #newDuration(
     *   boolean isPositive,
     *   BigInteger years,
     *   BigInteger months,
     *   BigInteger days,
     *   BigInteger hours,
     *   BigInteger minutes,
     *   BigDecimal seconds)
     */
    public Duration newDuration(
            final boolean isPositive,
            final int years,
            final int months,
            final int days,
            final int hours,
            final int minutes,
            final int seconds) {

        // years may not be set
        BigInteger realYears = (years != DatatypeConstants.FIELD_UNDEFINED) ? BigInteger.valueOf((long) years) : null;

        // months may not be set
        BigInteger realMonths = (months != DatatypeConstants.FIELD_UNDEFINED) ? BigInteger.valueOf((long) months) : null;

        // days may not be set
        BigInteger realDays = (days != DatatypeConstants.FIELD_UNDEFINED) ? BigInteger.valueOf((long) days) : null;

        // hours may not be set
        BigInteger realHours = (hours != DatatypeConstants.FIELD_UNDEFINED) ? BigInteger.valueOf((long) hours) : null;

        // minutes may not be set
        BigInteger realMinutes = (minutes != DatatypeConstants.FIELD_UNDEFINED) ? BigInteger.valueOf((long) minutes) : null;

        // seconds may not be set
        BigDecimal realSeconds = (seconds != DatatypeConstants.FIELD_UNDEFINED) ? BigDecimal.valueOf((long) seconds) : null;

        return newDuration(
                isPositive,
                realYears,
                realMonths,
                realDays,
                realHours,
                realMinutes,
                realSeconds
        );
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:dayTimeDuration</code> by parsing its <code>String</code> representation,
     * "<em>PnDTnHnMnS</em>", <a href="http://www.w3.org/TR/xpath-datamodel#dt-dayTimeDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:dayTimeDuration</a>.</p>
     * 
     * <p>The datatype <code>xdt:dayTimeDuration</code> is a subtype of <code>xs:duration</code>
     * whose lexical representation contains only day, hour, minute, and second components.
     * This datatype resides in the namespace <code>http://www.w3.org/2003/11/xpath-datatypes</code>.</p>
     * 
     * <p>All four values are set and available from the created {@link Duration}</p>
     * 
     * <p>The XML Schema specification states that values can be of an arbitrary size.
     * Implementations may chose not to or be incapable of supporting arbitrarily large and/or small values.
     * An {@link UnsupportedOperationException} will be thrown with a message indicating implementation limits
     * if implementation capacities are exceeded.</p>
     * 
     * @param lexicalRepresentation Lexical representation of a duration.
     * 
     * @return New <code>Duration</code> created using the specified <code>lexicalRepresentation</code>.
     * 
     * @throws IllegalArgumentException If the given string does not conform to the aforementioned specification.
     * @throws UnsupportedOperationException If implementation cannot support requested values.
     * @throws NullPointerException If <code>lexicalRepresentation</code> is <code>null</code>.
     */
    public Duration newDurationDayTime(final String lexicalRepresentation) {
        if (lexicalRepresentation == null) {
            throw new NullPointerException("The lexical representation cannot be null.");
        }
        // The lexical representation must match the pattern [^YM]*(T.*)?
        int pos = lexicalRepresentation.indexOf('T');
        int length = (pos >= 0) ? pos : lexicalRepresentation.length();
        for (int i = 0; i < length; ++i) {
            char c = lexicalRepresentation.charAt(i);
            if (c == 'Y' || c == 'M') {
                throw new IllegalArgumentException("Invalid dayTimeDuration value: " + lexicalRepresentation);
            }
        }
        return newDuration(lexicalRepresentation);
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:dayTimeDuration</code> using the specified milliseconds as defined in
     * <a href="http://www.w3.org/TR/xpath-datamodel#dt-dayTimeDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:dayTimeDuration</a>.</p>
     * 
     * <p>The datatype <code>xdt:dayTimeDuration</code> is a subtype of <code>xs:duration</code>
     * whose lexical representation contains only day, hour, minute, and second components.
     * This datatype resides in the namespace <code>http://www.w3.org/2003/11/xpath-datatypes</code>.</p>
     * 
     * <p>All four values are set by computing their values from the specified milliseconds
     * and are available using the <code>get</code> methods of  the created {@link Duration}.
     * The values conform to and are defined by:</p>
     * <ul>
     *   <li>ISO 8601:2000(E) Section 5.5.3.2 Alternative format</li>
     *   <li><a href="http://www.w3.org/TR/xmlschema-2/#isoformats">
     *     W3C XML Schema 1.0 Part 2, Appendix D, ISO 8601 Date and Time Formats</a>
     *   </li>
     *   <li>{@link XMLGregorianCalendar}  Date/Time Datatype Field Mapping Between XML Schema 1.0 and Java Representation</li>
     * </ul>
     * 
     * <p>The default start instance is defined by {@link GregorianCalendar}'s use of the start of the epoch: i.e.,
     * {@link java.util.Calendar#YEAR} = 1970,
     * {@link java.util.Calendar#MONTH} = {@link java.util.Calendar#JANUARY},
     * {@link java.util.Calendar#DATE} = 1, etc.
     * This is important as there are variations in the Gregorian Calendar,
     * e.g. leap years have different days in the month = {@link java.util.Calendar#FEBRUARY}
     * so the result of {@link Duration#getDays()} can be influenced.</p>
     * 
     * <p>Any remaining milliseconds after determining the day, hour, minute and second are discarded.</p>
     * 
     * @param durationInMilliseconds Milliseconds of <code>Duration</code> to create.
     * 
     * @return New <code>Duration</code> created with the specified <code>durationInMilliseconds</code>.
     * 
     * @see <a href="http://www.w3.org/TR/xpath-datamodel#dt-dayTimeDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:dayTimeDuration</a>
     */
    public Duration newDurationDayTime(final long durationInMilliseconds) {
        long _durationInMilliseconds = durationInMilliseconds;
        if (_durationInMilliseconds == 0) {
            return newDuration(true, DatatypeConstants.FIELD_UNDEFINED, 
                    DatatypeConstants.FIELD_UNDEFINED, 0, 0, 0, 0);
        }
        boolean tooLong = false;
        final boolean isPositive;
        if (_durationInMilliseconds < 0) {
            isPositive = false;
            if (_durationInMilliseconds == Long.MIN_VALUE) {
                _durationInMilliseconds++;
                tooLong = true;
            }
            _durationInMilliseconds *= -1;
        }
        else {
            isPositive = true;
        }
        
        long val = _durationInMilliseconds;
        int milliseconds = (int) (val % 60000L); // 60000 milliseconds per minute
        if (tooLong) {
            ++milliseconds;
        }
        if (milliseconds % 1000 == 0) {
            int seconds = milliseconds / 1000;
            val = val / 60000L;
            int minutes = (int) (val % 60L); // 60 minutes per hour
            val = val / 60L;
            int hours = (int) (val % 24L); // 24 hours per day
            long days = val / 24L;
            if (days <= ((long) Integer.MAX_VALUE)) {
                return newDuration(isPositive, DatatypeConstants.FIELD_UNDEFINED,
                        DatatypeConstants.FIELD_UNDEFINED, (int) days, hours, minutes, seconds);
            }
            else {
                return newDuration(isPositive, null, null,
                        BigInteger.valueOf(days), BigInteger.valueOf(hours), 
                        BigInteger.valueOf(minutes), BigDecimal.valueOf(milliseconds, 3));
            }   
        }
        
        BigDecimal seconds = BigDecimal.valueOf(milliseconds, 3);
        val = val / 60000L;
        BigInteger minutes = BigInteger.valueOf(val % 60L); // 60 minutes per hour
        val = val / 60L;
        BigInteger hours = BigInteger.valueOf(val % 24L); // 24 hours per day
        val = val / 24L;
        BigInteger days = BigInteger.valueOf(val);
        return newDuration(isPositive, null, null, days, hours, minutes, seconds);
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:dayTimeDuration</code> using the specified
     * <code>day</code>, <code>hour</code>, <code>minute</code> and <code>second</code> as defined in
     * <a href="http://www.w3.org/TR/xpath-datamodel#dt-dayTimeDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:dayTimeDuration</a>.</p>
     * 
     * <p>The datatype <code>xdt:dayTimeDuration</code> is a subtype of <code>xs:duration</code>
     * whose lexical representation contains only day, hour, minute, and second components.
     * This datatype resides in the namespace <code>http://www.w3.org/2003/11/xpath-datatypes</code>.</p>
     * 
     * <p>The XML Schema specification states that values can be of an arbitrary size.
     * Implementations may chose not to or be incapable of supporting arbitrarily large and/or small values.
     * An {@link UnsupportedOperationException} will be thrown with a message indicating implementation limits
     * if implementation capacities are exceeded.</p>
     * 
     * <p>A <code>null</code> value indicates that field is not set.</p>
     * 
     * @param isPositive Set to <code>false</code> to create a negative duration. When the length
     *   of the duration is zero, this parameter will be ignored.
     * @param day Day of <code>Duration</code>.
     * @param hour Hour of <code>Duration</code>.
     * @param minute Minute of <code>Duration</code>.
     * @param second Second of <code>Duration</code>.
     * 
     * @return New <code>Duration</code> created with the specified <code>day</code>, <code>hour</code>, <code>minute</code>
     * and <code>second</code>.
     * 
     * @throws IllegalArgumentException If any values would create an invalid <code>Duration</code>. 
     * @throws UnsupportedOperationException If implementation cannot support requested values.
     */	
    public Duration newDurationDayTime(
            final boolean isPositive,
            final BigInteger day,
            final BigInteger hour,
            final BigInteger minute,
            final BigInteger second) {

        return newDuration(
                isPositive,
                null,  // years
                null, // months
                day,
                hour,
                minute,
                (second != null)? new BigDecimal(second):null
        );
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:dayTimeDuration</code> using the specified
     * <code>day</code>, <code>hour</code>, <code>minute</code> and <code>second</code> as defined in
     * <a href="http://www.w3.org/TR/xpath-datamodel#dt-dayTimeDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:dayTimeDuration</a>.</p>
     * 
     * <p>The datatype <code>xdt:dayTimeDuration</code> is a subtype of <code>xs:duration</code>
     * whose lexical representation contains only day, hour, minute, and second components.
     * This datatype resides in the namespace <code>http://www.w3.org/2003/11/xpath-datatypes</code>.</p>
     * 
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param isPositive Set to <code>false</code> to create a negative duration. When the length
     *   of the duration is zero, this parameter will be ignored.
     * @param day Day of <code>Duration</code>.
     * @param hour Hour of <code>Duration</code>.
     * @param minute Minute of <code>Duration</code>.
     * @param second Second of <code>Duration</code>.
     * 
     * @return New <code>Duration</code> created with the specified <code>day</code>, <code>hour</code>, <code>minute</code>
     * and <code>second</code>.
     * 
     * @throws IllegalArgumentException If any values would create an invalid <code>Duration</code>. 
     */	
    public Duration newDurationDayTime(
            final boolean isPositive,
            final int day,
            final int hour,
            final int minute,
            final int second) {
        return newDuration(isPositive, 
                DatatypeConstants.FIELD_UNDEFINED, DatatypeConstants.FIELD_UNDEFINED,
                day, hour, minute, second);
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:yearMonthDuration</code> by parsing its <code>String</code> representation,
     * "<em>PnYnM</em>", <a href="http://www.w3.org/TR/xpath-datamodel#dt-yearMonthDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:yearMonthDuration</a>.</p>
     * 
     * <p>The datatype <code>xdt:yearMonthDuration</code> is a subtype of <code>xs:duration</code>
     * whose lexical representation contains only year and month components.
     * This datatype resides in the namespace {@link javax.xml.XMLConstants#W3C_XPATH_DATATYPE_NS_URI}.</p>
     * 
     * <p>Both values are set and available from the created {@link Duration}</p>
     * 
     * <p>The XML Schema specification states that values can be of an arbitrary size.
     * Implementations may chose not to or be incapable of supporting arbitrarily large and/or small values.
     * An {@link UnsupportedOperationException} will be thrown with a message indicating implementation limits
     * if implementation capacities are exceeded.</p>
     * 
     * @param lexicalRepresentation Lexical representation of a duration.
     * 
     * @return New <code>Duration</code> created using the specified <code>lexicalRepresentation</code>.
     * 
     * @throws IllegalArgumentException If the <code>lexicalRepresentation</code> does not conform to the specification.
     * @throws UnsupportedOperationException If implementation cannot support requested values.
     * @throws NullPointerException If <code>lexicalRepresentation</code> is <code>null</code>.
     */
    public Duration newDurationYearMonth(final String lexicalRepresentation) {
        if (lexicalRepresentation == null) {
            throw new NullPointerException("The lexical representation cannot be null.");
        }
        // The lexical representation must match the pattern [^DT]*.
        int length = lexicalRepresentation.length();
        for (int i = 0; i < length; ++i) {
            char c = lexicalRepresentation.charAt(i);
            if (c == 'D' || c == 'T') {
                throw new IllegalArgumentException("Invalid yearMonthDuration value: " + lexicalRepresentation);
            }
        }
        return newDuration(lexicalRepresentation);
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:yearMonthDuration</code> using the specified milliseconds as defined in
     * <a href="http://www.w3.org/TR/xpath-datamodel#dt-yearMonthDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:yearMonthDuration</a>.</p>
     * 
     * <p>The datatype <code>xdt:yearMonthDuration</code> is a subtype of <code>xs:duration</code>
     * whose lexical representation contains only year and month components.
     * This datatype resides in the namespace {@link javax.xml.XMLConstants#W3C_XPATH_DATATYPE_NS_URI}.</p>
     * 
     * <p>Both values are set by computing their values from the specified milliseconds
     * and are available using the <code>get</code> methods of  the created {@link Duration}.
     * The values conform to and are defined by:</p>
     * <ul>
     *   <li>ISO 8601:2000(E) Section 5.5.3.2 Alternative format</li>
     *   <li><a href="http://www.w3.org/TR/xmlschema-2/#isoformats">
     *     W3C XML Schema 1.0 Part 2, Appendix D, ISO 8601 Date and Time Formats</a>
     *   </li>
     *   <li>{@link XMLGregorianCalendar}  Date/Time Datatype Field Mapping Between XML Schema 1.0 and Java Representation</li>
     * </ul>
     * 
     * <p>The default start instance is defined by {@link GregorianCalendar}'s use of the start of the epoch: i.e.,
     * {@link java.util.Calendar#YEAR} = 1970,
     * {@link java.util.Calendar#MONTH} = {@link java.util.Calendar#JANUARY},
     * {@link java.util.Calendar#DATE} = 1, etc.
     * This is important as there are variations in the Gregorian Calendar,
     * e.g. leap years have different days in the month = {@link java.util.Calendar#FEBRUARY}
     * so the result of {@link Duration#getMonths()} can be influenced.</p>
     * 
     * <p>Any remaining milliseconds after determining the year and month are discarded.</p>
     * 
     * @param durationInMilliseconds Milliseconds of <code>Duration</code> to create.
     * 
     * @return New <code>Duration</code> created using the specified <code>durationInMilliseconds</code>.
     */
    public Duration newDurationYearMonth(final long durationInMilliseconds) {

        return newDuration(durationInMilliseconds);
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:yearMonthDuration</code> using the specified
     * <code>year</code> and <code>month</code> as defined in
     * <a href="http://www.w3.org/TR/xpath-datamodel#dt-yearMonthyDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:yearMonthDuration</a>.</p>
     * 
     * <p>The XML Schema specification states that values can be of an arbitrary size.
     * Implementations may chose not to or be incapable of supporting arbitrarily large and/or small values.
     * An {@link UnsupportedOperationException} will be thrown with a message indicating implementation limits
     * if implementation capacities are exceeded.</p>
     * 
     * <p>A <code>null</code> value indicates that field is not set.</p>
     * 
     * @param isPositive Set to <code>false</code> to create a negative duration. When the length
     *   of the duration is zero, this parameter will be ignored.
     * @param year Year of <code>Duration</code>.
     * @param month Month of <code>Duration</code>.
     * 
     * @return New <code>Duration</code> created using the specified <code>year</code> and <code>month</code>.
     * 
     * @throws IllegalArgumentException If any values would create an invalid <code>Duration</code>. 
     * @throws UnsupportedOperationException If implementation cannot support requested values.
     */	
    public Duration newDurationYearMonth(
            final boolean isPositive,
            final BigInteger year,
            final BigInteger month) {

        return newDuration(
                isPositive,
                year,
                month,
                null, // days
                null, // hours
                null, // minutes
                null  // seconds
        );
    }

    /**
     * <p>Create a <code>Duration</code> of type <code>xdt:yearMonthDuration</code> using the specified
     * <code>year</code> and <code>month</code> as defined in
     * <a href="http://www.w3.org/TR/xpath-datamodel#dt-yearMonthyDuration">
     *   XQuery 1.0 and XPath 2.0 Data Model, xdt:yearMonthDuration</a>.</p>
     * 
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param isPositive Set to <code>false</code> to create a negative duration. When the length
     *   of the duration is zero, this parameter will be ignored.
     * @param year Year of <code>Duration</code>.
     * @param month Month of <code>Duration</code>.
     * 
     * @return New <code>Duration</code> created using the specified <code>year</code> and <code>month</code>.
     * 
     * @throws IllegalArgumentException If any values would create an invalid <code>Duration</code>. 
     */	
    public Duration newDurationYearMonth(
            final boolean isPositive,
            final int year,
            final int month) {
        return newDuration(isPositive, year, month, 
                DatatypeConstants.FIELD_UNDEFINED, DatatypeConstants.FIELD_UNDEFINED,
                DatatypeConstants.FIELD_UNDEFINED, DatatypeConstants.FIELD_UNDEFINED);
    }

    /**
     * <p>Create a new instance of an <code>XMLGregorianCalendar</code>.</p>
     * 
     * <p>All date/time datatype fields set to {@link DatatypeConstants#FIELD_UNDEFINED} or null.</p>
     * 
     * @return New <code>XMLGregorianCalendar</code> with all date/time datatype fields set to
     *   {@link DatatypeConstants#FIELD_UNDEFINED} or null.
     */
    public abstract XMLGregorianCalendar newXMLGregorianCalendar();

    /**
     * <p>Create a new XMLGregorianCalendar by parsing the String as a lexical representation.</p>
     * 
     * <p>Parsing the lexical string representation is defined in 
     * <a href="http://www.w3.org/TR/xmlschema-2/#dateTime-order">XML Schema 1.0 Part 2, Section 3.2.[7-14].1,
     * <em>Lexical Representation</em>.</a></p>
     * 
     * <p>The string representation may not have any leading and trailing whitespaces.</p>
     * 
     * <p>The parsing is done field by field so that
     * the following holds for any lexically correct String x:</p>
     * <pre>
     * newXMLGregorianCalendar(x).toXMLFormat().equals(x)
     * </pre>
     * <p>Except for the noted lexical/canonical representation mismatches
     * listed in <a href="http://www.w3.org/2001/05/xmlschema-errata#e2-45">
     * XML Schema 1.0 errata, Section 3.2.7.2</a>.</p>
     * 
     * @param lexicalRepresentation Lexical representation of one the eight XML Schema date/time datatypes.
     * 
     * @return <code>XMLGregorianCalendar</code> created from the <code>lexicalRepresentation</code>.
     * 
     * @throws IllegalArgumentException If the <code>lexicalRepresentation</code> is not a valid <code>XMLGregorianCalendar</code>.
     * @throws NullPointerException If <code>lexicalRepresentation</code> is <code>null</code>.
     */
    public abstract XMLGregorianCalendar newXMLGregorianCalendar(final String lexicalRepresentation);

    /**
     * <p>Create an <code>XMLGregorianCalendar</code> from a {@link GregorianCalendar}.</p> 
     *
     * <table border="2" rules="all" cellpadding="2">
     *   <thead>
     *     <tr>
     *       <th align="center" colspan="2">
     *          Field by Field Conversion from
     *          {@link GregorianCalendar} to an {@link XMLGregorianCalendar} 
     *       </th>
     *     </tr>
     *     <tr>
     *        <th><code>java.util.GregorianCalendar</code> field</th>
     *        <th><code>javax.xml.datatype.XMLGregorianCalendar</code> field</th>
     *     </tr>
     *   </thead>
     *   <tbody>
     *     <tr>
     *       <td><code>ERA == GregorianCalendar.BC ? -YEAR : YEAR</code></td>
     *       <td>{@link XMLGregorianCalendar#setYear(int year)}</td>
     *     </tr>
     *     <tr>
     *       <td><code>MONTH + 1</code></td>
     *       <td>{@link XMLGregorianCalendar#setMonth(int month)}</td>
     *     </tr>
     *     <tr>
     *       <td><code>DAY_OF_MONTH</code></td>
     *       <td>{@link XMLGregorianCalendar#setDay(int day)}</td>
     *     </tr>
     *     <tr>
     *       <td><code>HOUR_OF_DAY, MINUTE, SECOND, MILLISECOND</code></td>
     *       <td>{@link XMLGregorianCalendar#setTime(int hour, int minute, int second, BigDecimal fractional)}</td>
     *     </tr>
     *     <tr>
     *       <td>
     *         <code>(ZONE_OFFSET + DST_OFFSET) / (60*1000)</code><br/>
     *         <em>(in minutes)</em>
     *       </td>
     *       <td>{@link XMLGregorianCalendar#setTimezone(int offset)}<sup><em>*</em></sup>
     *       </td>
     *     </tr>
     *   </tbody>
     * </table>
     * <p><em>*</em>conversion loss of information. It is not possible to represent 
     * a <code>java.util.GregorianCalendar</code> daylight savings timezone id in the 
     * XML Schema 1.0 date/time datatype representation.</p>
     * 
     * <p>To compute the return value's <code>TimeZone</code> field,
     * <ul>
     * <li>when <code>this.getTimezone() != FIELD_UNDEFINED</code>,
     * create a <code>java.util.TimeZone</code> with a custom timezone id 
     * using the <code>this.getTimezone()</code>.</li>
     * <li>else use the <code>GregorianCalendar</code> default timezone value 
     * for the host is defined as specified by 
     * <code>java.util.TimeZone.getDefault()</code>.</li></p>     
     *
     * @param cal <code>java.util.GregorianCalendar</code> used to create <code>XMLGregorianCalendar</code>
     * 
     * @return <code>XMLGregorianCalendar</code> created from <code>java.util.GregorianCalendar</code>
     *  
     * @throws NullPointerException If <code>cal</code> is <code>null</code>.
     */
    public abstract XMLGregorianCalendar newXMLGregorianCalendar(final GregorianCalendar cal);

    /**
     * <p>Constructor allowing for complete value spaces allowed by 
     * W3C XML Schema 1.0 recommendation for xsd:dateTime and related 
     * builtin datatypes. Note that <code>year</code> parameter supports
     * arbitrarily large numbers and fractionalSecond has infinite 
     * precision.</p>
     * 
     * <p>A <code>null</code> value indicates that field is not set.</p>
     * 
     * @param year of <code>XMLGregorianCalendar</code> to be created.
     * @param month of <code>XMLGregorianCalendar</code> to be created.
     * @param day of <code>XMLGregorianCalendar</code> to be created.
     * @param hour of <code>XMLGregorianCalendar</code> to be created.
     * @param minute of <code>XMLGregorianCalendar</code> to be created.
     * @param second of <code>XMLGregorianCalendar</code> to be created.
     * @param fractionalSecond of <code>XMLGregorianCalendar</code> to be created.
     * @param timezone of <code>XMLGregorianCalendar</code> to be created.
     * 
     * @return <code>XMLGregorianCalendar</code> created from specified values.
     * 
     * @throws IllegalArgumentException If any individual parameter's value is outside the maximum value constraint for the field
     *   as determined by the Date/Time Data Mapping table in {@link XMLGregorianCalendar}
     *   or if the composite values constitute an invalid <code>XMLGregorianCalendar</code> instance
     *   as determined by {@link XMLGregorianCalendar#isValid()}.
     */
    public abstract XMLGregorianCalendar newXMLGregorianCalendar(
            final BigInteger year,
            final int month,
            final int day,
            final int hour,
            final int minute,
            final int second,
            final BigDecimal fractionalSecond,
            final int timezone);

    /**
     * <p>Constructor of value spaces that a
     * <code>java.util.GregorianCalendar</code> instance would need to convert to an
     * <code>XMLGregorianCalendar</code> instance.</p>
     *    
     * <p><code>XMLGregorianCalendar eon</code> and 
     * <code>fractionalSecond</code> are set to <code>null</code></p>
     *
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param year of <code>XMLGregorianCalendar</code> to be created.
     * @param month of <code>XMLGregorianCalendar</code> to be created.
     * @param day of <code>XMLGregorianCalendar</code> to be created.
     * @param hour of <code>XMLGregorianCalendar</code> to be created.
     * @param minute of <code>XMLGregorianCalendar</code> to be created.
     * @param second of <code>XMLGregorianCalendar</code> to be created.
     * @param millisecond of <code>XMLGregorianCalendar</code> to be created.
     * @param timezone of <code>XMLGregorianCalendar</code> to be created.
     * 
     * @return <code>XMLGregorianCalendar</code> created from specified values.
     * 
     * @throws IllegalArgumentException If any individual parameter's value is outside the maximum value constraint for the field
     *   as determined by the Date/Time Data Mapping table in {@link XMLGregorianCalendar}
     *   or if the composite values constitute an invalid <code>XMLGregorianCalendar</code> instance
     *   as determined by {@link XMLGregorianCalendar#isValid()}.
     */
    public XMLGregorianCalendar newXMLGregorianCalendar(
            final int year,
            final int month,
            final int day,
            final int hour,
            final int minute,
            final int second,
            final int millisecond,
            final int timezone) {

        // year may be undefined
        BigInteger realYear = (year != DatatypeConstants.FIELD_UNDEFINED) ? BigInteger.valueOf((long) year) : null;

        // millisecond may be undefined
        // millisecond must be >= 0 millisecond <= 1000
        BigDecimal realMillisecond = null; // undefined value
        if (millisecond != DatatypeConstants.FIELD_UNDEFINED) {
            if (millisecond < 0 || millisecond > 1000) {
                throw new IllegalArgumentException(
                        "javax.xml.datatype.DatatypeFactory#newXMLGregorianCalendar("
                        + "int year, int month, int day, int hour, int minute, int second, int millisecond, int timezone)"
                        + "with invalid millisecond: " + millisecond
                );
            }
            realMillisecond = BigDecimal.valueOf((long) millisecond, 3);
        }

        return newXMLGregorianCalendar(
                realYear,
                month,
                day,
                hour,
                minute,
                second,
                realMillisecond,
                timezone
        );
    }

    /**
     * <p>Create a Java representation of XML Schema builtin datatype <code>date</code> or <code>g*</code>.</p>
     * 
     * <p>For example, an instance of <code>gYear</code> can be created invoking this factory 
     * with <code>month</code> and <code>day</code> parameters set to 
     * {@link DatatypeConstants#FIELD_UNDEFINED}.</p>
     * 
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param year of <code>XMLGregorianCalendar</code> to be created.
     * @param month of <code>XMLGregorianCalendar</code> to be created.
     * @param day of <code>XMLGregorianCalendar</code> to be created.
     * @param timezone offset in minutes. {@link DatatypeConstants#FIELD_UNDEFINED} indicates optional field is not set.
     * 
     * @return <code>XMLGregorianCalendar</code> created from parameter values.
     * 
     * @see DatatypeConstants#FIELD_UNDEFINED
     *
     * @throws IllegalArgumentException If any individual parameter's value is outside the maximum value constraint for the field
     *   as determined by the Date/Time Data Mapping table in {@link XMLGregorianCalendar}
     *   or if the composite values constitute an invalid <code>XMLGregorianCalendar</code> instance
     *   as determined by {@link XMLGregorianCalendar#isValid()}.
     */
    public XMLGregorianCalendar newXMLGregorianCalendarDate(
            final int year,
            final int month,
            final int day,
            final int timezone) {

        return newXMLGregorianCalendar(
                year,
                month,
                day,
                DatatypeConstants.FIELD_UNDEFINED, // hour
                DatatypeConstants.FIELD_UNDEFINED, // minute
                DatatypeConstants.FIELD_UNDEFINED, // second
                DatatypeConstants.FIELD_UNDEFINED, // millisecond
                timezone);
    }

    /**
     * <p>Create a Java instance of XML Schema builtin datatype <code>time</code>.</p>
     * 
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param hours number of hours
     * @param minutes number of minutes
     * @param seconds number of seconds
     * @param timezone offset in minutes. {@link DatatypeConstants#FIELD_UNDEFINED} indicates optional field is not set.
     * 
     * @return <code>XMLGregorianCalendar</code> created from parameter values.
     * 
     * @throws IllegalArgumentException If any individual parameter's value is outside the maximum value constraint for the field
     *   as determined by the Date/Time Data Mapping table in {@link XMLGregorianCalendar}
     *   or if the composite values constitute an invalid <code>XMLGregorianCalendar</code> instance
     *   as determined by {@link XMLGregorianCalendar#isValid()}.
     *  
     * @see DatatypeConstants#FIELD_UNDEFINED
     */
    public XMLGregorianCalendar newXMLGregorianCalendarTime(
            final int hours,
            final int minutes,
            final int seconds,
            final int timezone) {

        return newXMLGregorianCalendar(
                DatatypeConstants.FIELD_UNDEFINED, // Year
                DatatypeConstants.FIELD_UNDEFINED, // Month
                DatatypeConstants.FIELD_UNDEFINED, // Day
                hours,
                minutes,
                seconds,
                DatatypeConstants.FIELD_UNDEFINED, //Millisecond
                timezone);
    }

    /**
     * <p>Create a Java instance of XML Schema builtin datatype time.</p>
     * 
     * <p>A <code>null</code> value indicates that field is not set.</p>
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param hours number of hours
     * @param minutes number of minutes
     * @param seconds number of seconds
     * @param fractionalSecond value of <code>null</code> indicates that this optional field is not set.
     * @param timezone offset in minutes. {@link DatatypeConstants#FIELD_UNDEFINED} indicates optional field is not set.
     * 
     * @return <code>XMLGregorianCalendar</code> created from parameter values.
     * 
     * @see DatatypeConstants#FIELD_UNDEFINED
     *
     * @throws IllegalArgumentException If any individual parameter's value is outside the maximum value constraint for the field
     *   as determined by the Date/Time Data Mapping table in {@link XMLGregorianCalendar}
     *   or if the composite values constitute an invalid <code>XMLGregorianCalendar</code> instance
     *   as determined by {@link XMLGregorianCalendar#isValid()}.
     */
    public XMLGregorianCalendar newXMLGregorianCalendarTime(
            final int hours,
            final int minutes,
            final int seconds,
            final BigDecimal fractionalSecond,
            final int timezone) {

        return newXMLGregorianCalendar(
                null, // year
                DatatypeConstants.FIELD_UNDEFINED, // month
                DatatypeConstants.FIELD_UNDEFINED, // day
                hours,
                minutes,
                seconds,
                fractionalSecond,
                timezone);
    }

    /**
     * <p>Create a Java instance of XML Schema builtin datatype time.</p>
     * 
     * <p>A {@link DatatypeConstants#FIELD_UNDEFINED} value indicates that field is not set.</p>
     * 
     * @param hours number of hours
     * @param minutes number of minutes
     * @param seconds number of seconds
     * @param milliseconds number of milliseconds
     * @param timezone offset in minutes. {@link DatatypeConstants#FIELD_UNDEFINED} indicates optional field is not set.
     * 
     * @return <code>XMLGregorianCalendar</code> created from parameter values.
     * 
     * @see DatatypeConstants#FIELD_UNDEFINED
     *
     * @throws IllegalArgumentException If any individual parameter's value is outside the maximum value constraint for the field
     *   as determined by the Date/Time Data Mapping table in {@link XMLGregorianCalendar}
     *   or if the composite values constitute an invalid <code>XMLGregorianCalendar</code> instance
     *   as determined by {@link XMLGregorianCalendar#isValid()}.
     */
    public XMLGregorianCalendar newXMLGregorianCalendarTime(
            final int hours,
            final int minutes,
            final int seconds,
            final int milliseconds,
            final int timezone) {

        // millisecond may be undefined
        // millisecond must be >= 0 millisecond <= 1000
        BigDecimal realMilliseconds = null; // undefined value
        if (milliseconds != DatatypeConstants.FIELD_UNDEFINED) {
            if (milliseconds < 0 || milliseconds > 1000) {
                throw new IllegalArgumentException(
                        "javax.xml.datatype.DatatypeFactory#newXMLGregorianCalendarTime("
                        + "int hours, int minutes, int seconds, int milliseconds, int timezone)"
                        + "with invalid milliseconds: " + milliseconds
                );
            }
            realMilliseconds = BigDecimal.valueOf((long) milliseconds, 3);
        }

        return newXMLGregorianCalendarTime(
                hours,
                minutes,
                seconds,
                realMilliseconds,
                timezone
        );
    }
}
