http://www.joda.org/joda-time/: Date and time library to replace JDK date handling (Joda.org) 
/*
 *  Copyright 2001-2005 Stephen Colebourne
 *
 *  Licensed 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.
 */
package org.joda.time;

import java.io.Serializable;


Identifies a field, such as year or minuteOfHour, in a chronology-neutral way.

 A field type defines the type of the field, such as hourOfDay. If does not directly enable any calculations, however it does provide a getField(Chronology) method that returns the actual calculation engine for a particular chronology. It also provides access to the related DurationFieldTypes. 

Instances of DateTimeFieldType are singletons.
They can be compared using ==.


If required, you can create your own field, for example a quarterOfYear.
You must create a subclass of DateTimeFieldType that defines the field type. This class returns the actual calculation engine from getField(Chronology). The subclass should implement equals and hashCode. 
Author:Stephen Colebourne, Brian S O'Neill
Since:1.0
/**
 * Identifies a field, such as year or minuteOfHour, in a chronology-neutral way.
 * <p>
 * A field type defines the type of the field, such as hourOfDay.
 * If does not directly enable any calculations, however it does provide a
 * {@link #getField(Chronology)} method that returns the actual calculation engine
 * for a particular chronology.
 * It also provides access to the related {@link DurationFieldType}s.
 * <p>
 * Instances of <code>DateTimeFieldType</code> are singletons.
 * They can be compared using <code>==</code>.
 * <p>
 * If required, you can create your own field, for example a quarterOfYear.
 * You must create a subclass of <code>DateTimeFieldType</code> that defines the field type.
 * This class returns the actual calculation engine from {@link #getField(Chronology)}.
 * The subclass should implement equals and hashCode.
 *
 * @author Stephen Colebourne
 * @author Brian S O'Neill
 * @since 1.0
 */
public abstract class DateTimeFieldType implements Serializable {

    
Serialization version 
/** Serialization version */
    private static final long serialVersionUID = -42615285973990L;

    
Ordinal values for standard field types. 
/** Ordinal values for standard field types. */
    static final byte
        ERA = 1,
        YEAR_OF_ERA = 2,
        CENTURY_OF_ERA = 3,
        YEAR_OF_CENTURY = 4,
        YEAR = 5,
        DAY_OF_YEAR = 6,
        MONTH_OF_YEAR = 7,
        DAY_OF_MONTH = 8,
        WEEKYEAR_OF_CENTURY = 9,
        WEEKYEAR = 10,
        WEEK_OF_WEEKYEAR = 11,
        DAY_OF_WEEK = 12,
        HALFDAY_OF_DAY = 13,
        HOUR_OF_HALFDAY = 14,
        CLOCKHOUR_OF_HALFDAY = 15,
        CLOCKHOUR_OF_DAY = 16,
        HOUR_OF_DAY = 17,
        MINUTE_OF_DAY = 18,
        MINUTE_OF_HOUR = 19,
        SECOND_OF_DAY = 20,
        SECOND_OF_MINUTE = 21,
        MILLIS_OF_DAY = 22,
        MILLIS_OF_SECOND = 23;

    
The era field type. 
/** The era field type. */
    private static final DateTimeFieldType ERA_TYPE = new StandardDateTimeFieldType(
        "era", ERA, DurationFieldType.eras(), null);
    
The yearOfEra field type. 
/** The yearOfEra field type. */
    private static final DateTimeFieldType YEAR_OF_ERA_TYPE = new StandardDateTimeFieldType(
        "yearOfEra", YEAR_OF_ERA, DurationFieldType.years(), DurationFieldType.eras());
    
The centuryOfEra field type. 
/** The centuryOfEra field type. */
    private static final DateTimeFieldType CENTURY_OF_ERA_TYPE = new StandardDateTimeFieldType(
        "centuryOfEra", CENTURY_OF_ERA, DurationFieldType.centuries(), DurationFieldType.eras());
    
The yearOfCentury field type. 
/** The yearOfCentury field type. */
    private static final DateTimeFieldType YEAR_OF_CENTURY_TYPE = new StandardDateTimeFieldType(
        "yearOfCentury", YEAR_OF_CENTURY, DurationFieldType.years(), DurationFieldType.centuries());
    
The year field type. 
/** The year field type. */
    private static final DateTimeFieldType YEAR_TYPE = new StandardDateTimeFieldType(
        "year", YEAR, DurationFieldType.years(), null);
    
The dayOfYear field type. 
/** The dayOfYear field type. */
    private static final DateTimeFieldType DAY_OF_YEAR_TYPE = new StandardDateTimeFieldType(
        "dayOfYear", DAY_OF_YEAR, DurationFieldType.days(), DurationFieldType.years());
    
The monthOfYear field type. 
/** The monthOfYear field type. */
    private static final DateTimeFieldType MONTH_OF_YEAR_TYPE = new StandardDateTimeFieldType(
        "monthOfYear", MONTH_OF_YEAR, DurationFieldType.months(), DurationFieldType.years());
    
The dayOfMonth field type. 
/** The dayOfMonth field type. */
    private static final DateTimeFieldType DAY_OF_MONTH_TYPE = new StandardDateTimeFieldType(
        "dayOfMonth", DAY_OF_MONTH, DurationFieldType.days(), DurationFieldType.months());
    
The weekyearOfCentury field type. 
/** The weekyearOfCentury field type. */
    private static final DateTimeFieldType WEEKYEAR_OF_CENTURY_TYPE = new StandardDateTimeFieldType(
        "weekyearOfCentury", WEEKYEAR_OF_CENTURY, DurationFieldType.weekyears(), DurationFieldType.centuries());
    
The weekyear field type. 
/** The weekyear field type. */
    private static final DateTimeFieldType WEEKYEAR_TYPE = new StandardDateTimeFieldType(
        "weekyear", WEEKYEAR, DurationFieldType.weekyears(), null);
    
The weekOfWeekyear field type. 
/** The weekOfWeekyear field type. */
    private static final DateTimeFieldType WEEK_OF_WEEKYEAR_TYPE = new StandardDateTimeFieldType(
        "weekOfWeekyear", WEEK_OF_WEEKYEAR, DurationFieldType.weeks(), DurationFieldType.weekyears());
    
The dayOfWeek field type. 
/** The dayOfWeek field type. */
    private static final DateTimeFieldType DAY_OF_WEEK_TYPE = new StandardDateTimeFieldType(
        "dayOfWeek", DAY_OF_WEEK, DurationFieldType.days(), DurationFieldType.weeks());

    
The halfday field type. 
/** The halfday field type. */
    private static final DateTimeFieldType HALFDAY_OF_DAY_TYPE = new StandardDateTimeFieldType(
        "halfdayOfDay", HALFDAY_OF_DAY, DurationFieldType.halfdays(), DurationFieldType.days());
    
The hourOfHalfday field type. 
/** The hourOfHalfday field type. */
    private static final DateTimeFieldType HOUR_OF_HALFDAY_TYPE = new StandardDateTimeFieldType(
        "hourOfHalfday", HOUR_OF_HALFDAY, DurationFieldType.hours(), DurationFieldType.halfdays());
    
The clockhourOfHalfday field type. 
/** The clockhourOfHalfday field type. */
    private static final DateTimeFieldType CLOCKHOUR_OF_HALFDAY_TYPE = new StandardDateTimeFieldType(
        "clockhourOfHalfday", CLOCKHOUR_OF_HALFDAY, DurationFieldType.hours(), DurationFieldType.halfdays());
    
The clockhourOfDay field type. 
/** The clockhourOfDay field type. */
    private static final DateTimeFieldType CLOCKHOUR_OF_DAY_TYPE = new StandardDateTimeFieldType(
        "clockhourOfDay", CLOCKHOUR_OF_DAY, DurationFieldType.hours(), DurationFieldType.days());
    
The hourOfDay field type. 
/** The hourOfDay field type. */
    private static final DateTimeFieldType HOUR_OF_DAY_TYPE = new StandardDateTimeFieldType(
        "hourOfDay", HOUR_OF_DAY, DurationFieldType.hours(), DurationFieldType.days());
    
The minuteOfDay field type. 
/** The minuteOfDay field type. */
    private static final DateTimeFieldType MINUTE_OF_DAY_TYPE = new StandardDateTimeFieldType(
        "minuteOfDay", MINUTE_OF_DAY, DurationFieldType.minutes(), DurationFieldType.days());
    
The minuteOfHour field type. 
/** The minuteOfHour field type. */
    private static final DateTimeFieldType MINUTE_OF_HOUR_TYPE = new StandardDateTimeFieldType(
        "minuteOfHour", MINUTE_OF_HOUR, DurationFieldType.minutes(), DurationFieldType.hours());
    
The secondOfDay field type. 
/** The secondOfDay field type. */
    private static final DateTimeFieldType SECOND_OF_DAY_TYPE = new StandardDateTimeFieldType(
        "secondOfDay", SECOND_OF_DAY, DurationFieldType.seconds(), DurationFieldType.days());
    
The secondOfMinute field type. 
/** The secondOfMinute field type. */
    private static final DateTimeFieldType SECOND_OF_MINUTE_TYPE = new StandardDateTimeFieldType(
        "secondOfMinute", SECOND_OF_MINUTE, DurationFieldType.seconds(), DurationFieldType.minutes());
    
The millisOfDay field type. 
/** The millisOfDay field type. */
    private static final DateTimeFieldType MILLIS_OF_DAY_TYPE = new StandardDateTimeFieldType(
        "millisOfDay", MILLIS_OF_DAY, DurationFieldType.millis(), DurationFieldType.days());
    
The millisOfSecond field type. 
/** The millisOfSecond field type. */
    private static final DateTimeFieldType MILLIS_OF_SECOND_TYPE = new StandardDateTimeFieldType(
        "millisOfSecond", MILLIS_OF_SECOND, DurationFieldType.millis(), DurationFieldType.seconds());

    
The name of the field. 
/** The name of the field. */
    private final String iName;

    //-----------------------------------------------------------------------
    
Constructor.

Params:
  • name –  the name to use
/**
     * Constructor.
     * 
     * @param name  the name to use
     */
    protected DateTimeFieldType(String name) {
        super();
        iName = name;
    }

    //-----------------------------------------------------------------------
    
Get the millis of second field type.

Returns:the DateTimeFieldType constant
/**
     * Get the millis of second field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType millisOfSecond() {
        return MILLIS_OF_SECOND_TYPE;
    }

    
Get the millis of day field type.


This measures the milliseconds from the start of the day on the local time-line.
On a daylight saving date, this means that some values will be missed (in spring)
or duplicated (in autumn/fall).

Returns:the DateTimeFieldType constant
/**
     * Get the millis of day field type.
     * <p>
     * This measures the milliseconds from the start of the day on the <b>local</b> time-line.
     * On a daylight saving date, this means that some values will be missed (in spring)
     * or duplicated (in autumn/fall).
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType millisOfDay() {
        return MILLIS_OF_DAY_TYPE;
    }

    
Get the second of minute field type.

Returns:the DateTimeFieldType constant
/**
     * Get the second of minute field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType secondOfMinute() {
        return SECOND_OF_MINUTE_TYPE;
    }

    
Get the second of day field type.


This measures the seconds from the start of the day on the local time-line.
On a daylight saving date, this means that some values will be missed (in spring)
or duplicated (in autumn/fall).

Returns:the DateTimeFieldType constant
/**
     * Get the second of day field type.
     * <p>
     * This measures the seconds from the start of the day on the <b>local</b> time-line.
     * On a daylight saving date, this means that some values will be missed (in spring)
     * or duplicated (in autumn/fall).
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType secondOfDay() {
        return SECOND_OF_DAY_TYPE;
    }

    
Get the minute of hour field type.

Returns:the DateTimeFieldType constant
/**
     * Get the minute of hour field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType minuteOfHour() {
        return MINUTE_OF_HOUR_TYPE;
    }

    
Get the minute of day field type.


This measures the minutes from the start of the day on the local time-line.
On a daylight saving date, this means that some values will be missed (in spring)
or duplicated (in autumn/fall).

Returns:the DateTimeFieldType constant
/**
     * Get the minute of day field type.
     * <p>
     * This measures the minutes from the start of the day on the <b>local</b> time-line.
     * On a daylight saving date, this means that some values will be missed (in spring)
     * or duplicated (in autumn/fall).
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType minuteOfDay() {
        return MINUTE_OF_DAY_TYPE;
    }

    
Get the hour of day (0-23) field type.

Returns:the DateTimeFieldType constant
/**
     * Get the hour of day (0-23) field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType hourOfDay() {
        return HOUR_OF_DAY_TYPE;
    }

    
Get the hour of day (offset to 1-24) field type.

Returns:the DateTimeFieldType constant
/**
     * Get the hour of day (offset to 1-24) field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType clockhourOfDay() {
        return CLOCKHOUR_OF_DAY_TYPE;
    }

    
Get the hour of am/pm (0-11) field type.

Returns:the DateTimeFieldType constant
/**
     * Get the hour of am/pm (0-11) field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType hourOfHalfday() {
        return HOUR_OF_HALFDAY_TYPE;
    }

    
Get the hour of am/pm (offset to 1-12) field type.

Returns:the DateTimeFieldType constant
/**
     * Get the hour of am/pm (offset to 1-12) field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType clockhourOfHalfday() {
        return CLOCKHOUR_OF_HALFDAY_TYPE;
    }

    
Get the AM(0) PM(1) field type.

Returns:the DateTimeFieldType constant
/**
     * Get the AM(0) PM(1) field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType halfdayOfDay() {
        return HALFDAY_OF_DAY_TYPE;
    }

    //-----------------------------------------------------------------------
    
Get the day of week field type.

Returns:the DateTimeFieldType constant
/**
     * Get the day of week field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType dayOfWeek() {
        return DAY_OF_WEEK_TYPE;
    }

    
Get the day of month field type.

Returns:the DateTimeFieldType constant
/**
     * Get the day of month field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType dayOfMonth() {
        return DAY_OF_MONTH_TYPE;
    }

    
Get the day of year field type.

Returns:the DateTimeFieldType constant
/**
     * Get the day of year field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType dayOfYear() {
        return DAY_OF_YEAR_TYPE;
    }

    
Get the week of a week based year field type.

Returns:the DateTimeFieldType constant
/**
     * Get the week of a week based year field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType weekOfWeekyear() {
        return WEEK_OF_WEEKYEAR_TYPE;
    }

    
Get the year of a week based year field type.

Returns:the DateTimeFieldType constant
/**
     * Get the year of a week based year field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType weekyear() {
        return WEEKYEAR_TYPE;
    }

    
Get the year of a week based year within a century field type.

Returns:the DateTimeFieldType constant
/**
     * Get the year of a week based year within a century field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType weekyearOfCentury() {
        return WEEKYEAR_OF_CENTURY_TYPE;
    }

    
Get the month of year field type.

Returns:the DateTimeFieldType constant
/**
     * Get the month of year field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType monthOfYear() {
        return MONTH_OF_YEAR_TYPE;
    }

    
Get the year field type.

Returns:the DateTimeFieldType constant
/**
     * Get the year field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType year() {
        return YEAR_TYPE;
    }

    
Get the year of era field type.

Returns:the DateTimeFieldType constant
/**
     * Get the year of era field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType yearOfEra() {
        return YEAR_OF_ERA_TYPE;
    }

    
Get the year of century field type.

Returns:the DateTimeFieldType constant
/**
     * Get the year of century field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType yearOfCentury() {
        return YEAR_OF_CENTURY_TYPE;
    }

    
Get the century of era field type.

Returns:the DateTimeFieldType constant
/**
     * Get the century of era field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType centuryOfEra() {
        return CENTURY_OF_ERA_TYPE;
    }

    
Get the era field type.

Returns:the DateTimeFieldType constant
/**
     * Get the era field type.
     * 
     * @return the DateTimeFieldType constant
     */
    public static DateTimeFieldType era() {
        return ERA_TYPE;
    }

    //-----------------------------------------------------------------------
    
Get the name of the field.


By convention, names follow a pattern of "dddOfRrr", where "ddd" represents
the (singular) duration unit field name and "Rrr" represents the (singular)
duration range field name. If the range field is not applicable, then
the name of the field is simply the (singular) duration field name.

Returns:field name
/**
     * Get the name of the field.
     * <p>
     * By convention, names follow a pattern of "dddOfRrr", where "ddd" represents
     * the (singular) duration unit field name and "Rrr" represents the (singular)
     * duration range field name. If the range field is not applicable, then
     * the name of the field is simply the (singular) duration field name.
     * 
     * @return field name
     */
    public String getName() {
        return iName;
    }

    
Get the duration unit of the field.

Returns:duration unit of the field, never null
/**
     * Get the duration unit of the field.
     * 
     * @return duration unit of the field, never null
     */
    public abstract DurationFieldType getDurationType();

    
Get the duration range of the field.

Returns:duration range of the field, null if unbounded
/**
     * Get the duration range of the field.
     * 
     * @return duration range of the field, null if unbounded
     */
    public abstract DurationFieldType getRangeDurationType();

    
Gets a suitable field for this type from the given Chronology.

Params:
  • chronology –  the chronology to use, null means ISOChronology in default zone
Returns:a suitable field
/**
     * Gets a suitable field for this type from the given Chronology.
     *
     * @param chronology  the chronology to use, null means ISOChronology in default zone
     * @return a suitable field
     */
    public abstract DateTimeField getField(Chronology chronology);

    
Checks whether this field supported in the given Chronology.

Params:
  • chronology –  the chronology to use, null means ISOChronology in default zone
Returns:true if supported
/**
     * Checks whether this field supported in the given Chronology.
     *
     * @param chronology  the chronology to use, null means ISOChronology in default zone
     * @return true if supported
     */
    public boolean isSupported(Chronology chronology) {
        return getField(chronology).isSupported();
    }

    
Get a suitable debug string.

Returns:debug string
/**
     * Get a suitable debug string.
     * 
     * @return debug string
     */
    public String toString() {
        return getName();
    }

    private static class StandardDateTimeFieldType extends DateTimeFieldType {
        
Serialization version 
/** Serialization version */
        private static final long serialVersionUID = -9937958251642L;

        
The ordinal of the standard field type, for switch statements 
/** The ordinal of the standard field type, for switch statements */
        private final byte iOrdinal;

        
The unit duration of the field. 
/** The unit duration of the field. */
        private final transient DurationFieldType iUnitType;
        
The range duration of the field. 
/** The range duration of the field. */
        private final transient DurationFieldType iRangeType;

        
Constructor.

Params:
  • name –  the name to use
  • ordinal –  the byte value for the ordinal index
  • unitType –  the unit duration type
  • rangeType –  the range duration type
/**
         * Constructor.
         * 
         * @param name  the name to use
         * @param ordinal  the byte value for the ordinal index
         * @param unitType  the unit duration type
         * @param rangeType  the range duration type
         */
        StandardDateTimeFieldType(String name, byte ordinal,
                                  DurationFieldType unitType, DurationFieldType rangeType) {
            super(name);
            iOrdinal = ordinal;
            iUnitType = unitType;
            iRangeType = rangeType;
        }

        
@inheritdoc
/** @inheritdoc */
        public DurationFieldType getDurationType() {
            return iUnitType;
        }

        
@inheritdoc
/** @inheritdoc */
        public DurationFieldType getRangeDurationType() {
            return iRangeType;
        }

        
@inheritdoc
/** @inheritdoc */
        @Override
        public boolean equals(Object obj) {
            if (this == obj) {
                return true;
            }
            if (obj instanceof StandardDateTimeFieldType) {
                return iOrdinal == ((StandardDateTimeFieldType) obj).iOrdinal;
            }
            return false;
        }

        
@inheritdoc
/** @inheritdoc */
        @Override
        public int hashCode() {
            return (1 << iOrdinal);
        }

        
@inheritdoc
/** @inheritdoc */
        public DateTimeField getField(Chronology chronology) {
            chronology = DateTimeUtils.getChronology(chronology);

            switch (iOrdinal) {
                case ERA:
                    return chronology.era();
                case YEAR_OF_ERA:
                    return chronology.yearOfEra();
                case CENTURY_OF_ERA:
                    return chronology.centuryOfEra();
                case YEAR_OF_CENTURY:
                    return chronology.yearOfCentury();
                case YEAR:
                    return chronology.year();
                case DAY_OF_YEAR:
                    return chronology.dayOfYear();
                case MONTH_OF_YEAR:
                    return chronology.monthOfYear();
                case DAY_OF_MONTH:
                    return chronology.dayOfMonth();
                case WEEKYEAR_OF_CENTURY:
                    return chronology.weekyearOfCentury();
                case WEEKYEAR:
                    return chronology.weekyear();
                case WEEK_OF_WEEKYEAR:
                    return chronology.weekOfWeekyear();
                case DAY_OF_WEEK:
                    return chronology.dayOfWeek();
                case HALFDAY_OF_DAY:
                    return chronology.halfdayOfDay();
                case HOUR_OF_HALFDAY:
                    return chronology.hourOfHalfday();
                case CLOCKHOUR_OF_HALFDAY:
                    return chronology.clockhourOfHalfday();
                case CLOCKHOUR_OF_DAY:
                    return chronology.clockhourOfDay();
                case HOUR_OF_DAY:
                    return chronology.hourOfDay();
                case MINUTE_OF_DAY:
                    return chronology.minuteOfDay();
                case MINUTE_OF_HOUR:
                    return chronology.minuteOfHour();
                case SECOND_OF_DAY:
                    return chronology.secondOfDay();
                case SECOND_OF_MINUTE:
                    return chronology.secondOfMinute();
                case MILLIS_OF_DAY:
                    return chronology.millisOfDay();
                case MILLIS_OF_SECOND:
                    return chronology.millisOfSecond();
                default:
                    // Shouldn't happen.
                    throw new InternalError();
            }
        }

        
Ensure a singleton is returned.

Returns:the singleton type
/**
         * Ensure a singleton is returned.
         * 
         * @return the singleton type
         */
        private Object readResolve() {
            switch (iOrdinal) {
                case ERA:
                    return ERA_TYPE;
                case YEAR_OF_ERA:
                    return YEAR_OF_ERA_TYPE;
                case CENTURY_OF_ERA:
                    return CENTURY_OF_ERA_TYPE;
                case YEAR_OF_CENTURY:
                    return YEAR_OF_CENTURY_TYPE;
                case YEAR:
                    return YEAR_TYPE;
                case DAY_OF_YEAR:
                    return DAY_OF_YEAR_TYPE;
                case MONTH_OF_YEAR:
                    return MONTH_OF_YEAR_TYPE;
                case DAY_OF_MONTH:
                    return DAY_OF_MONTH_TYPE;
                case WEEKYEAR_OF_CENTURY:
                    return WEEKYEAR_OF_CENTURY_TYPE;
                case WEEKYEAR:
                    return WEEKYEAR_TYPE;
                case WEEK_OF_WEEKYEAR:
                    return WEEK_OF_WEEKYEAR_TYPE;
                case DAY_OF_WEEK:
                    return DAY_OF_WEEK_TYPE;
                case HALFDAY_OF_DAY:
                    return HALFDAY_OF_DAY_TYPE;
                case HOUR_OF_HALFDAY:
                    return HOUR_OF_HALFDAY_TYPE;
                case CLOCKHOUR_OF_HALFDAY:
                    return CLOCKHOUR_OF_HALFDAY_TYPE;
                case CLOCKHOUR_OF_DAY:
                    return CLOCKHOUR_OF_DAY_TYPE;
                case HOUR_OF_DAY:
                    return HOUR_OF_DAY_TYPE;
                case MINUTE_OF_DAY:
                    return MINUTE_OF_DAY_TYPE;
                case MINUTE_OF_HOUR:
                    return MINUTE_OF_HOUR_TYPE;
                case SECOND_OF_DAY:
                    return SECOND_OF_DAY_TYPE;
                case SECOND_OF_MINUTE:
                    return SECOND_OF_MINUTE_TYPE;
                case MILLIS_OF_DAY:
                    return MILLIS_OF_DAY_TYPE;
                case MILLIS_OF_SECOND:
                    return MILLIS_OF_SECOND_TYPE;
                default:
                    // Shouldn't happen.
                    return this;
            }
        }
    }

}