Package org.joda.time

Class MonthDay

  • All Implemented Interfaces:
    java.io.Serializable, java.lang.Comparable<ReadablePartial>, ReadablePartial
    public final class MonthDay
extends BasePartial
implements ReadablePartial, java.io.Serializable
    MonthDay is an immutable partial supporting the monthOfYear and dayOfMonth fields.

    NOTE: This class only supports the two fields listed above. It is impossible to query any other fields, such as dayOfWeek or centuryOfEra.

    Calculations on MonthDay are performed using a Chronology. This chronology is set to be in the UTC time zone for all calculations.

    One use case for this class is to store a birthday without the year (to avoid storing the age of the person). This class can be used as the gMonthDay type in XML Schema.

    Each individual field can be queried in two ways:

    • getMonthOfYear()
    • monthOfYear().get()
    The second technique also provides access to other useful methods on the field:
    • numeric value - monthOfYear().get()
    • text value - monthOfYear().getAsText()
    • short text value - monthOfYear().getAsShortText()
    • maximum/minimum values - monthOfYear().getMaximumValue()
    • add/subtract - monthOfYear().addToCopy()
    • set - monthOfYear().setCopy()

    MonthDay is thread-safe and immutable, provided that the Chronology is as well. All standard Chronology classes supplied are thread-safe and immutable.

    Since:
    2.0
    See Also:
    Serialized Form

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  MonthDay.Property
      The property class for MonthDay.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int DAY_OF_MONTH
      The index of the day field in the field array
      static int MONTH_OF_YEAR
      The index of the monthOfYear field in the field array

    • Constructor Summary

      Constructors 
      Constructor Description
      MonthDay()
      Constructs a MonthDay with the current monthOfYear, using ISOChronology in the default zone to extract the fields.
      MonthDay​(int monthOfYear, int dayOfMonth)
      Constructs a MonthDay with specified year and month using ISOChronology.
      MonthDay​(int monthOfYear, int dayOfMonth, Chronology chronology)
      Constructs an instance set to the specified monthOfYear and dayOfMonth using the specified chronology, whose zone is ignored.
      MonthDay​(long instant)
      Constructs a MonthDay extracting the partial fields from the specified milliseconds using the ISOChronology in the default zone.
      MonthDay​(long instant, Chronology chronology)
      Constructs a MonthDay extracting the partial fields from the specified milliseconds using the chronology provided.
      MonthDay​(java.lang.Object instant)
      Constructs a MonthDay from an Object that represents some form of time.
      MonthDay​(java.lang.Object instant, Chronology chronology)
      Constructs a MonthDay from an Object that represents some form of time, using the specified chronology.
      MonthDay​(Chronology chronology)
      Constructs a MonthDay with the current month-day, using the specified chronology and zone to extract the fields.
      MonthDay​(DateTimeZone zone)
      Constructs a MonthDay with the current month-day, using ISOChronology in the specified zone to extract the fields.

    • Field Detail

      • MONTH_OF_YEAR

        public static final int MONTH_OF_YEAR
        The index of the monthOfYear field in the field array
        See Also:
        Constant Field Values

      • DAY_OF_MONTH

        public static final int DAY_OF_MONTH
        The index of the day field in the field array
        See Also:
        Constant Field Values

    • Constructor Detail

      • MonthDay

        public MonthDay()
        Constructs a MonthDay with the current monthOfYear, using ISOChronology in the default zone to extract the fields.

        The constructor uses the default time zone, resulting in the local time being initialised. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        See Also:
        now()

      • MonthDay

        public MonthDay​(DateTimeZone zone)
        Constructs a MonthDay with the current month-day, using ISOChronology in the specified zone to extract the fields.

        The constructor uses the specified time zone to obtain the current month-day. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        Parameters:
        zone - the zone to use, null means default zone
        See Also:
        now(DateTimeZone)

      • MonthDay

        public MonthDay​(Chronology chronology)
        Constructs a MonthDay with the current month-day, using the specified chronology and zone to extract the fields.

        The constructor uses the time zone of the chronology specified. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        Parameters:
        chronology - the chronology, null means ISOChronology in the default zone
        See Also:
        now(Chronology)

      • MonthDay

        public MonthDay​(long instant)
        Constructs a MonthDay extracting the partial fields from the specified milliseconds using the ISOChronology in the default zone.

        The constructor uses the default time zone, resulting in the local time being initialised. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        Parameters:
        instant - the milliseconds from 1970-01-01T00:00:00Z

      • MonthDay

        public MonthDay​(long instant,
                Chronology chronology)
        Constructs a MonthDay extracting the partial fields from the specified milliseconds using the chronology provided.

        The constructor uses the time zone of the chronology specified. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        Parameters:
        instant - the milliseconds from 1970-01-01T00:00:00Z
        chronology - the chronology, null means ISOChronology in the default zone

      • MonthDay

        public MonthDay​(java.lang.Object instant)
        Constructs a MonthDay from an Object that represents some form of time.

        The recognised object types are defined in ConverterManager and include ReadableInstant, String, Calendar and Date. The String formats are described by ISODateTimeFormat.localDateParser().

        The chronology used will be derived from the object, defaulting to ISO.

        Parameters:
        instant - the date-time object, null means now
        Throws:
        java.lang.IllegalArgumentException - if the instant is invalid

      • MonthDay

        public MonthDay​(java.lang.Object instant,
                Chronology chronology)
        Constructs a MonthDay from an Object that represents some form of time, using the specified chronology.

        The recognised object types are defined in ConverterManager and include ReadableInstant, String, Calendar and Date. The String formats are described by ISODateTimeFormat.localDateParser().

        The constructor uses the time zone of the chronology specified. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC). The specified chronology overrides that of the object.

        Parameters:
        instant - the date-time object, null means now
        chronology - the chronology, null means ISO default
        Throws:
        java.lang.IllegalArgumentException - if the instant is invalid

      • MonthDay

        public MonthDay​(int monthOfYear,
                int dayOfMonth)
        Constructs a MonthDay with specified year and month using ISOChronology.

        The constructor uses the no time zone initialising the fields as provided. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        Parameters:
        monthOfYear - the month of the year
        dayOfMonth - the day of the month

      • MonthDay

        public MonthDay​(int monthOfYear,
                int dayOfMonth,
                Chronology chronology)
        Constructs an instance set to the specified monthOfYear and dayOfMonth using the specified chronology, whose zone is ignored.

        If the chronology is null, ISOChronology is used.

        The constructor uses the time zone of the chronology specified. Once the constructor is complete, all further calculations are performed without reference to a time-zone (by switching to UTC).

        Parameters:
        monthOfYear - the month of the year
        dayOfMonth - the day of the month
        chronology - the chronology, null means ISOChronology in the default zone

    • Method Detail

      • now

        public static MonthDay now()
        Obtains a MonthDay set to the current system millisecond time using ISOChronology in the default time zone. The resulting object does not use the zone.
        Returns:
        the current month-day, not null
        Since:
        2.0

      • now

        public static MonthDay now​(DateTimeZone zone)
        Obtains a MonthDay set to the current system millisecond time using ISOChronology in the specified time zone. The resulting object does not use the zone.
        Parameters:
        zone - the time zone, not null
        Returns:
        the current month-day, not null
        Since:
        2.0

      • now

        public static MonthDay now​(Chronology chronology)
        Obtains a MonthDay set to the current system millisecond time using the specified chronology. The resulting object does not use the zone.
        Parameters:
        chronology - the chronology, not null
        Returns:
        the current month-day, not null
        Since:
        2.0

      • parse

        public static MonthDay parse​(java.lang.String str)
        Parses a MonthDay from the specified string.

        This uses ISODateTimeFormat.localDateParser() or the format --MM-dd.

        Parameters:
        str - the string to parse, not null
        Since:
        2.0

      • parse

        public static MonthDay parse​(java.lang.String str,
                             DateTimeFormatter formatter)
        Parses a MonthDay from the specified string using a formatter.
        Parameters:
        str - the string to parse, not null
        formatter - the formatter to use, not null
        Since:
        2.0

      • fromCalendarFields

        public static MonthDay fromCalendarFields​(java.util.Calendar calendar)
        Constructs a MonthDay from a java.util.Calendar using exactly the same field values avoiding any time zone effects.

        Each field is queried from the Calendar and assigned to the MonthDay.

        This factory method ignores the type of the calendar and always creates a MonthDay with ISO chronology. It is expected that you will only pass in instances of GregorianCalendar however this is not validated.

        Parameters:
        calendar - the Calendar to extract fields from
        Returns:
        the created MonthDay, never null
        Throws:
        java.lang.IllegalArgumentException - if the calendar is null
        java.lang.IllegalArgumentException - if the monthOfYear or dayOfMonth is invalid for the ISO chronology

      • fromDateFields

        public static MonthDay fromDateFields​(java.util.Date date)
        Constructs a MonthDay from a java.util.Date using exactly the same field values avoiding any time zone effects.

        Each field is queried from the Date and assigned to the MonthDay.

        This factory method always creates a MonthDay with ISO chronology.

        Parameters:
        date - the Date to extract fields from
        Returns:
        the created MonthDay, never null
        Throws:
        java.lang.IllegalArgumentException - if the calendar is null
        java.lang.IllegalArgumentException - if the monthOfYear or dayOfMonth is invalid for the ISO chronology

      • size

        public int size()
        Gets the number of fields in this partial, which is two. The supported fields are MonthOfYear and DayOfMonth. Note that only these fields may be queried.
        Specified by:
        size in interface ReadablePartial
        Returns:
        the field count, two

      • getFieldType

        public DateTimeFieldType getFieldType​(int index)
        Gets the field type at the specified index.
        Specified by:
        getFieldType in interface ReadablePartial
        Overrides:
        getFieldType in class AbstractPartial
        Parameters:
        index - the index to retrieve
        Returns:
        the field at the specified index, never null
        Throws:
        java.lang.IndexOutOfBoundsException - if the index is invalid

      • getFieldTypes

        public DateTimeFieldType[] getFieldTypes()
        Gets an array of the field type of each of the fields that this partial supports.

        The fields are returned largest to smallest, Month, Day.

        Overrides:
        getFieldTypes in class AbstractPartial
        Returns:
        the array of field types (cloned), largest to smallest, never null

      • withChronologyRetainFields

        public MonthDay withChronologyRetainFields​(Chronology newChronology)
        Returns a copy of this month-day with the specified chronology. This instance is immutable and unaffected by this method call.

        This method retains the values of the fields, thus the result will typically refer to a different instant.

        The time zone of the specified chronology is ignored, as MonthDay operates without a time zone.

        Parameters:
        newChronology - the new chronology, null means ISO
        Returns:
        a copy of this month-day with a different chronology, never null
        Throws:
        java.lang.IllegalArgumentException - if the values are invalid for the new chronology

      • withField

        public MonthDay withField​(DateTimeFieldType fieldType,
                          int value)
        Returns a copy of this month-day with the specified field set to a new value.

        For example, if the field type is dayOfMonth then the day would be changed in the returned instance.

        These three lines are equivalent: 

         MonthDay updated = md.withField(DateTimeFieldType.dayOfMonth(), 6);
 MonthDay updated = md.dayOfMonth().setCopy(6);
 MonthDay updated = md.property(DateTimeFieldType.dayOfMonth()).setCopy(6);
        Parameters:
        fieldType - the field type to set, not null
        value - the value to set
        Returns:
        a copy of this instance with the field set, never null
        Throws:
        java.lang.IllegalArgumentException - if the value is null or invalid

      • withFieldAdded

        public MonthDay withFieldAdded​(DurationFieldType fieldType,
                               int amount)
        Returns a copy of this month-day with the value of the specified field increased.

        If the addition is zero, then this is returned.

        These three lines are equivalent: 

         MonthDay added = md.withFieldAdded(DurationFieldType.days(), 6);
 MonthDay added = md.plusDays(6);
 MonthDay added = md.dayOfMonth().addToCopy(6);
        Parameters:
        fieldType - the field type to add to, not null
        amount - the amount to add
        Returns:
        a copy of this instance with the field updated, never null
        Throws:
        java.lang.IllegalArgumentException - if the value is null or invalid
        java.lang.ArithmeticException - if the new date-time exceeds the capacity

      • withPeriodAdded

        public MonthDay withPeriodAdded​(ReadablePeriod period,
                                int scalar)
        Returns a copy of this month-day with the specified period added.

        If the addition is zero, then this is returned. Fields in the period that aren't present in the partial are ignored.

        This method is typically used to add multiple copies of complex period instances. Adding one field is best achieved using methods like withFieldAdded(DurationFieldType, int) or plusMonths(int).

        Parameters:
        period - the period to add to this one, null means zero
        scalar - the amount of times to add, such as -1 to subtract once
        Returns:
        a copy of this instance with the period added, never null
        Throws:
        java.lang.ArithmeticException - if the new date-time exceeds the capacity

      • plus

        public MonthDay plus​(ReadablePeriod period)
        Returns a copy of this month-day with the specified period added.

        If the amount is zero or null, then this is returned.

        This method is typically used to add complex period instances. Adding one field is best achieved using methods like plusMonths(int).

        Parameters:
        period - the duration to add to this one, null means zero
        Returns:
        a copy of this instance with the period added, never null
        Throws:
        java.lang.ArithmeticException - if the new month-day exceeds the capacity

      • plusMonths

        public MonthDay plusMonths​(int months)
        Returns a copy of this month-day plus the specified number of months.

        This month-day instance is immutable and unaffected by this method call. The month will wrap at the end of the year from December to January. The day will be adjusted to the last valid value if necessary.

        The following three lines are identical in effect: 

         MonthDay added = md.plusMonths(6);
 MonthDay added = md.plus(Period.months(6));
 MonthDay added = md.withFieldAdded(DurationFieldType.months(), 6);
        Parameters:
        months - the amount of months to add, may be negative
        Returns:
        the new month-day plus the increased months, never null

      • plusDays

        public MonthDay plusDays​(int days)
        Returns a copy of this month-day plus the specified number of days.

        This month-day instance is immutable and unaffected by this method call. The month will wrap at the end of the year from December to January.

        If the number of days added requires wrapping past the end of February, the wrapping will be calculated assuming February has 29 days.

        The following three lines are identical in effect: 

         MonthDay added = md.plusDays(6);
 MonthDay added = md.plus(Period.days(6));
 MonthDay added = md.withFieldAdded(DurationFieldType.days(), 6);
        Parameters:
        days - the amount of days to add, may be negative
        Returns:
        the new month-day plus the increased days, never null

      • minus

        public MonthDay minus​(ReadablePeriod period)
        Returns a copy of this month-day with the specified period taken away.

        If the amount is zero or null, then this is returned.

        This method is typically used to subtract complex period instances. Subtracting one field is best achieved using methods like minusMonths(int).

        Parameters:
        period - the period to reduce this instant by
        Returns:
        a copy of this instance with the period taken away, never null
        Throws:
        java.lang.ArithmeticException - if the new month-day exceeds the capacity

      • minusMonths

        public MonthDay minusMonths​(int months)
        Returns a copy of this month-day minus the specified number of months.

        This MonthDay instance is immutable and unaffected by this method call. The month will wrap at the end of the year from January to December. The day will be adjusted to the last valid value if necessary.

        The following three lines are identical in effect: 

         MonthDay subtracted = md.minusMonths(6);
 MonthDay subtracted = md.minus(Period.months(6));
 MonthDay subtracted = md.withFieldAdded(DurationFieldType.months(), -6);
        Parameters:
        months - the amount of months to subtract, may be negative
        Returns:
        the new month-day minus the increased months, never null

      • minusDays

        public MonthDay minusDays​(int days)
        Returns a copy of this month-day minus the specified number of months.

        This month-day instance is immutable and unaffected by this method call. The month will wrap at the end of the year from January to December.

        The following three lines are identical in effect: 

         MonthDay subtracted = md.minusDays(6);
 MonthDay subtracted = md.minus(Period.days(6));
 MonthDay subtracted = md.withFieldAdded(DurationFieldType.days(), -6);
        Parameters:
        days - the amount of days to subtract, may be negative
        Returns:
        the new month-day minus the increased days, never null

      • toLocalDate

        public LocalDate toLocalDate​(int year)
        Converts this object to a LocalDate with the same month-day and chronology.
        Parameters:
        year - the year to use, valid for chronology
        Returns:
        a LocalDate with the same month-day and chronology, never null

      • getMonthOfYear

        public int getMonthOfYear()
        Get the month of year field value.
        Returns:
        the month of year

      • getDayOfMonth

        public int getDayOfMonth()
        Get the day of month field value.
        Returns:
        the day of month

      • withMonthOfYear

        public MonthDay withMonthOfYear​(int monthOfYear)
        Returns a copy of this month-day with the month of year field updated.

        MonthDay is immutable, so there are no set methods. Instead, this method returns a new instance with the value of month of year changed.

        Parameters:
        monthOfYear - the month of year to set
        Returns:
        a copy of this object with the field set, never null
        Throws:
        java.lang.IllegalArgumentException - if the value is invalid

      • withDayOfMonth

        public MonthDay withDayOfMonth​(int dayOfMonth)
        Returns a copy of this month-day with the day of month field updated.

        MonthDay is immutable, so there are no set methods. Instead, this method returns a new instance with the value of day of month changed.

        Parameters:
        dayOfMonth - the day of month to set
        Returns:
        a copy of this object with the field set, never null
        Throws:
        java.lang.IllegalArgumentException - if the value is invalid

      • property

        public MonthDay.Property property​(DateTimeFieldType type)
        Gets the property object for the specified type, which contains many useful methods.
        Parameters:
        type - the field type to get the property for
        Returns:
        the property object
        Throws:
        java.lang.IllegalArgumentException - if the field is null or unsupported

      • monthOfYear

        public MonthDay.Property monthOfYear()
        Get the month of year field property which provides access to advanced functionality.
        Returns:
        the month of year property

      • dayOfMonth

        public MonthDay.Property dayOfMonth()
        Get the day of month field property which provides access to advanced functionality.
        Returns:
        the day of month property

      • toString

        public java.lang.String toString()
        Output the month-day in ISO8601 format (--MM-dd).
        Specified by:
        toString in interface ReadablePartial
        Overrides:
        toString in class java.lang.Object
        Returns:
        ISO8601 time formatted string.

      • toString

        public java.lang.String toString​(java.lang.String pattern)
        Output the month-day using the specified format pattern.
        Overrides:
        toString in class BasePartial
        Parameters:
        pattern - the pattern specification, null means use toString
        See Also:
        DateTimeFormat

      • toString

        public java.lang.String toString​(java.lang.String pattern,
                                 java.util.Locale locale)
                          throws java.lang.IllegalArgumentException
        Output the month-day using the specified format pattern.
        Overrides:
        toString in class BasePartial
        Parameters:
        pattern - the pattern specification, null means use toString
        locale - Locale to use, null means default
        Throws:
        java.lang.IllegalArgumentException
        See Also:
        DateTimeFormat