java.lang.Object
- javax.time.calendar.MonthDay

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<MonthDay>, Calendrical, CalendricalMatcher, DateAdjuster
```
public final class MonthDay
extends java.lang.Object
implements Calendrical, CalendricalMatcher, DateAdjuster, java.lang.Comparable<MonthDay>, java.io.Serializable
```
A month-day in the ISO-8601 calendar system, such as --12-03.
MonthDay is an immutable calendrical that represents the combination of a year and month. Any field that can be derived from a month and day, such as quarter-of-year, can be obtained.
This class does not store or represent a year, time or time-zone. Thus, for example, the value "3rd December" can be stored in a MonthDay.
Since a MonthDay does not possess a year, the leap day of 29th of February is considered valid.
The ISO-8601 calendar system is the modern civil calendar system used today in most of the world. It is equivalent to the proleptic Gregorian calendar system, in which todays's rules for leap years are applied for all time. For most applications written today, the ISO-8601 rules are entirely suitable. Any application that uses historical dates should consider using HistoricDate.
MonthDay is immutable and thread-safe.

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class Description

(package private) static class MonthDay.Rule
Rule implementation.

Field Summary

Fields
Modifier and Type	Field	Description
`private int`	`day`	The day-of-month.
`private MonthOfYear`	`month`	The month-of-year, not null.
`private static DateTimeFormatter`	`PARSER`	Parser.
`private static long`	`serialVersionUID`	A serialization identifier for this class.

Constructor Summary

Constructors
Modifier Constructor Description

private MonthDay(MonthOfYear monthOfYear, int dayOfMonth)
Constructor, previously validated.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`LocalDate`	`adjustDate(LocalDate date)`	Adjusts a date to have the value of this month-day, returning a new date.
`LocalDate`	`adjustDate(LocalDate date, DateResolver resolver)`	Adjusts a date to have the value of this month-day, using a resolver to handle the case when the day-of-month becomes invalid.
`LocalDate`	`atYear(int year)`	Returns a date formed from this month-day at the specified year.
`int`	`compareTo(MonthDay other)`	Compares this month-day to another month-day.
`boolean`	`equals(java.lang.Object other)`	Is this month-day equal to the specified month-day.
`<T> T`	`get(CalendricalRule<T> rule)`	Gets the value of the specified calendrical rule.
`ISOChronology`	`getChronology()`	Gets the chronology that this month-day uses, which is the ISO calendar system.
`int`	`getDayOfMonth()`	Gets the day-of-month field.
`MonthOfYear`	`getMonthOfYear()`	Gets the month-of-year field, which is an enum `MonthOfYear`.
`int`	`hashCode()`	A hash code for this month-day.
`boolean`	`isAfter(MonthDay other)`	Is this month-day after the specified month-day.
`boolean`	`isBefore(MonthDay other)`	Is this month-day before the specified month-day.
`boolean`	`isValidYear(int year)`	Checks if the year is valid for this month-day.
`boolean`	`matchesCalendrical(Calendrical calendrical)`	Checks if the month-day extracted from the calendrical matches this.
`static MonthDay`	`now()`	Obtains the current month-day from the system clock in the default time-zone.
`static MonthDay`	`now(Clock clock)`	Obtains the current month-day from the specified clock.
`static MonthDay`	`of(int monthOfYear, int dayOfMonth)`	Obtains an instance of `MonthDay`.
`static MonthDay`	`of(Calendrical calendrical)`	Obtains an instance of `MonthDay` from a Calendrical.
`static MonthDay`	`of(MonthOfYear monthOfYear, int dayOfMonth)`	Obtains an instance of `MonthDay`.
`static MonthDay`	`parse(java.lang.String text)`	Obtains an instance of `MonthDay` from a text string such as `--12-03`.
`static MonthDay`	`parse(java.lang.String text, DateTimeFormatter formatter)`	Obtains an instance of `MonthDay` from a text string using a specific formatter.
`MonthDay`	`rollDayOfMonth(int days)`	Rolls the day-of-month, adding the specified number of days to a copy of this `MonthDay`.
`MonthDay`	`rollMonthOfYear(int months)`	Rolls the month-of-year, adding the specified number of months to a copy of this `MonthDay`.
`static CalendricalRule<MonthDay>`	`rule()`	Gets the rule for the month-day.
`java.lang.String`	`toString()`	Outputs this month-day as a `String`, such as `--12-03`.
`java.lang.String`	`toString(DateTimeFormatter formatter)`	Outputs this month-day as a `String` using the formatter.
`MonthDay`	`with(MonthOfYear monthOfYear)`	Returns a copy of this `MonthDay` with the month-of-year altered.
`private MonthDay`	`with(MonthOfYear newMonth, int newDay)`	Returns a copy of this month-day with the new month and day, checking to see if a new object is in fact required.
`MonthDay`	`withDayOfMonth(int dayOfMonth)`	Returns a copy of this `MonthDay` with the day-of-month altered.
`MonthDay`	`withMonthOfYear(int monthOfYear)`	Returns a copy of this `MonthDay` with the month-of-year altered.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - serialVersionUID
```
private static final long serialVersionUID
```
    A serialization identifier for this class.
    
    See Also:
    
    Constant Field Values
  - PARSER
```
private static final DateTimeFormatter PARSER
```
    Parser.
  - month
```
private final MonthOfYear month
```
    The month-of-year, not null.
  - day
```
private final int day
```
    The day-of-month.
- Constructor Detail
  - MonthDay
```
private MonthDay(MonthOfYear monthOfYear,
                 int dayOfMonth)
```
    Constructor, previously validated.
    
    Parameters:
    
    monthOfYear - the month-of-year to represent, validated not null
    
    dayOfMonth - the day-of-month to represent, validated from 1 to 29-31
- Method Detail
  - now
```
public static MonthDay now()
```
    Obtains the current month-day from the system clock in the default time-zone.
    This will query the system clock in the default time-zone to obtain the current month-day.
    Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.
    
    Returns:
    
    the current month-day using the system clock, never null
  - now
```
public static MonthDay now(Clock clock)
```
    Obtains the current month-day from the specified clock.
    This will query the specified clock to obtain the current month-day. Using this method allows the use of an alternate clock for testing. The alternate clock may be introduced using dependency injection.
    
    Parameters:
    
    clock - the clock to use, not null
    
    Returns:
    
    the current month-day, never null
  - of
```
public static MonthDay of(MonthOfYear monthOfYear,
                          int dayOfMonth)
```
    Obtains an instance of MonthDay.
    The day-of-month must be valid for the month within a leap year. Hence, for February, day 29 is valid.
    For example, passing in April and day 31 will throw an exception, as there can never be a 31st April in any year. Alternately, passing in 29th February is valid, as that month-day can be valid.
    
    Parameters:
    
    monthOfYear - the month-of-year to represent, not null
    
    dayOfMonth - the day-of-month to represent, from 1 to 31
    
    Returns:
    
    the month-day, never null
    
    Throws:
    
    IllegalCalendarFieldValueException - if the value of any field is out of range
    
    InvalidCalendarFieldException - if the day-of-month is invalid for the month
  - of
```
public static MonthDay of(int monthOfYear,
                          int dayOfMonth)
```
    Obtains an instance of MonthDay.
    The day-of-month must be valid for the month within a leap year. Hence, for month 2 (February), day 29 is valid.
    For example, passing in month 4 (April) and day 31 will throw an exception, as there can never be a 31st April in any year. Alternately, passing in 29th February is valid, as that month-day can be valid.
    
    Parameters:
    
    monthOfYear - the month-of-year to represent, from 1 (January) to 12 (December)
    
    dayOfMonth - the day-of-month to represent, from 1 to 31
    
    Returns:
    
    the month-day, never null
    
    Throws:
    
    IllegalCalendarFieldValueException - if the value of any field is out of range
    
    InvalidCalendarFieldException - if the day-of-month is invalid for the month
  - of
```
public static MonthDay of(Calendrical calendrical)
```
    Obtains an instance of MonthDay from a Calendrical.
    This method will create a MonthDay from the Calendrical by extracting the month-of-year and day-of-month fields.
    
    Parameters:
    
    calendrical - the calendrical to use, not null
    
    Returns:
    
    the month-day, never null
    
    Throws:
    
    UnsupportedRuleException - if either field cannot be found
    
    InvalidCalendarFieldException - if the value for either field is invalid
  - parse
```
public static MonthDay parse(java.lang.String text)
```
    Obtains an instance of MonthDay from a text string such as --12-03.
    The following formats are accepted in ASCII:
    
    --{monthOfYear}-{dayOfMonth}
    The month-of-year has 2 digits and has values from 1 to 12.
    The day-of-month has 2 digits with values from 1 to 31 appropriate to the month.
    Parameters:
    
    text - the text to parse such as '--12-03', not null
    
    Returns:
    
    the parsed month-day, never null
    
    Throws:
    
    CalendricalException - if the text cannot be parsed
  - parse
```
public static MonthDay parse(java.lang.String text,
                             DateTimeFormatter formatter)
```
    Obtains an instance of MonthDay from a text string using a specific formatter.
    The text is parsed using the formatter, returning a month-day.
    
    Parameters:
    
    text - the text to parse, not null
    
    formatter - the formatter to use, not null
    
    Returns:
    
    the parsed month-day, never null
    
    Throws:
    
    java.lang.UnsupportedOperationException - if the formatter cannot parse
    
    CalendricalException - if the text cannot be parsed
  - with
```
private MonthDay with(MonthOfYear newMonth,
                      int newDay)
```
    Returns a copy of this month-day with the new month and day, checking to see if a new object is in fact required.
    
    Parameters:
    
    newMonth - the month-of-year to represent, validated not null
    
    newDay - the day-of-month to represent, validated from 1 to 31
    
    Returns:
    
    the month-day, never null
  - getChronology
```
public ISOChronology getChronology()
```
    Gets the chronology that this month-day uses, which is the ISO calendar system.
    
    Returns:
    
    the ISO chronology, never null
  - get
```
public <T> T get(CalendricalRule<T> rule)
```
    Gets the value of the specified calendrical rule.
    This method queries the value of the specified calendrical rule. If the value cannot be returned for the rule from this month-day then null will be returned.
    
    Specified by:
    
    get in interface Calendrical
    
    Parameters:
    
    rule - the rule to use, not null
    
    Returns:
    
    the value for the rule, null if the value cannot be returned
  - getMonthOfYear
```
public MonthOfYear getMonthOfYear()
```
    Gets the month-of-year field, which is an enum MonthOfYear.
    This method returns the enum MonthOfYear for the month. This avoids confusion as to what int values mean. If you need access to the primitive int value then the enum provides the int value.
    Additional information can be obtained from the MonthOfYear. This includes month lengths, textual names and access to the quarter-of-year and month-of-quarter values.
    
    Returns:
    
    the month-of-year, never null
  - getDayOfMonth
```
public int getDayOfMonth()
```
    Gets the day-of-month field.
    This method returns the primitive int value for the day-of-month.
    
    Returns:
    
    the day-of-month, from 1 to 31
  - with
```
public MonthDay with(MonthOfYear monthOfYear)
```
    Returns a copy of this MonthDay with the month-of-year altered.
    If the day-of-month is invalid for the specified month, the day will be adjusted to the last valid day-of-month.
    This instance is immutable and unaffected by this method call.
    
    Parameters:
    
    monthOfYear - the month-of-year to set in the returned month-day, not null
    
    Returns:
    
    a MonthDay based on this month-day with the requested month, never null
  - withMonthOfYear
```
public MonthDay withMonthOfYear(int monthOfYear)
```
    Returns a copy of this MonthDay with the month-of-year altered.
    If the day-of-month is invalid for the specified month, the day will be adjusted to the last valid day-of-month.
    This instance is immutable and unaffected by this method call.
    
    Parameters:
    
    monthOfYear - the month-of-year to set in the returned month-day, from 1 (January) to 12 (December)
    
    Returns:
    
    a MonthDay based on this month-day with the requested month, never null
    
    Throws:
    
    IllegalCalendarFieldValueException - if the month-of-year value is invalid
  - withDayOfMonth
```
public MonthDay withDayOfMonth(int dayOfMonth)
```
    Returns a copy of this MonthDay with the day-of-month altered.
    If the day-of-month is invalid for the current month, an exception will be thrown.
    This instance is immutable and unaffected by this method call.
    
    Parameters:
    
    dayOfMonth - the day-of-month to set in the return month-day, from 1 to 31
    
    Returns:
    
    a MonthDay based on this month-day with the requested day, never null
    
    Throws:
    
    IllegalCalendarFieldValueException - if the day-of-month value is invalid
    
    InvalidCalendarFieldException - if the day-of-month is invalid for the month
  - rollMonthOfYear
```
public MonthDay rollMonthOfYear(int months)
```
    Rolls the month-of-year, adding the specified number of months to a copy of this MonthDay.
    This method will add the specified number of months to the month-day, rolling from December back to January if necessary.
    If the day-of-month is invalid for the specified month in the result, the day will be adjusted to the last valid day-of-month.
    This instance is immutable and unaffected by this method call.
    
    Parameters:
    
    months - the months to roll by, positive or negative
    
    Returns:
    
    a MonthDay based on this month-day with the month rolled, never null
  - rollDayOfMonth
```
public MonthDay rollDayOfMonth(int days)
```
    Rolls the day-of-month, adding the specified number of days to a copy of this MonthDay.
    This method will add the specified number of days to the month-day, rolling from last day-of-month to the first if necessary.
    This instance is immutable and unaffected by this method call.
    
    Parameters:
    
    days - the days to roll by, positive or negative
    
    Returns:
    
    a MonthDay based on this month-day with the day rolled, never null
  - matchesCalendrical
```
public boolean matchesCalendrical(Calendrical calendrical)
```
    Checks if the month-day extracted from the calendrical matches this.
    This method implements the CalendricalMatcher interface. It is intended that applications use LocalDate.matches(javax.time.calendar.CalendricalMatcher) rather than this method.
    
    Specified by:
    
    matchesCalendrical in interface CalendricalMatcher
    
    Parameters:
    
    calendrical - the calendrical to match, not null
    
    Returns:
    
    true if the calendrical matches, false otherwise
  - adjustDate
```
public LocalDate adjustDate(LocalDate date)
```
    Adjusts a date to have the value of this month-day, returning a new date.
    This method implements the DateAdjuster interface. It is intended that, instead of calling this method directly, it is used from an instance of LocalDate:
    date = date.with(monthDay);
    
    This implementation handles the case where this represents February 29 and the year is not a leap year by throwing an exception.
    This instance is immutable and unaffected by this method call.
    Specified by:
    
    adjustDate in interface DateAdjuster
    
    Parameters:
    
    date - the date to be adjusted, not null
    
    Returns:
    
    the adjusted date, never null
    
    Throws:
    
    InvalidCalendarFieldException - if the day-of-month is invalid for the year
  - adjustDate
```
public LocalDate adjustDate(LocalDate date,
                            DateResolver resolver)
```
    Adjusts a date to have the value of this month-day, using a resolver to handle the case when the day-of-month becomes invalid.
    This instance is immutable and unaffected by this method call.
    
    Parameters:
    
    date - the date to be adjusted, not null
    
    resolver - the date resolver to use if the day-of-month is invalid, not null
    
    Returns:
    
    the adjusted date, never null
    
    Throws:
    
    InvalidCalendarFieldException - if the day-of-month is invalid for the year
  - isValidYear
```
public boolean isValidYear(int year)
```
    Checks if the year is valid for this month-day.
    This method checks whether this month and day and the input year form a valid date.
    
    Parameters:
    
    year - the year to validate, an out of range value returns false
    
    Returns:
    
    true if the year is valid for this month-day
    
    See Also:
    
    Year.isValidMonthDay(MonthDay)
  - atYear
```
public LocalDate atYear(int year)
```
    Returns a date formed from this month-day at the specified year.
    This method merges this and the specified year to form an instance of LocalDate.
    LocalDate date = monthDay.atYear(year);
    
    This instance is immutable and unaffected by this method call.
    Parameters:
    
    year - the year to use, from MIN_YEAR to MAX_YEAR
    
    Returns:
    
    the local date formed from this month-day and the specified year, never null
    
    See Also:
    
    Year.atMonthDay(MonthDay)
  - compareTo
```
public int compareTo(MonthDay other)
```
    Compares this month-day to another month-day.
    
    Specified by:
    
    compareTo in interface java.lang.Comparable<MonthDay>
    
    Parameters:
    
    other - the other month-day to compare to, not null
    
    Returns:
    
    the comparator value, negative if less, positive if greater
    
    Throws:
    
    java.lang.NullPointerException - if other is null
  - isAfter
```
public boolean isAfter(MonthDay other)
```
    Is this month-day after the specified month-day.
    
    Parameters:
    
    other - the other month-day to compare to, not null
    
    Returns:
    
    true if this is after the specified month-day
    
    Throws:
    
    java.lang.NullPointerException - if other is null
  - isBefore
```
public boolean isBefore(MonthDay other)
```
    Is this month-day before the specified month-day.
    
    Parameters:
    
    other - the other month-day to compare to, not null
    
    Returns:
    
    true if this point is before the specified month-day
    
    Throws:
    
    java.lang.NullPointerException - if other is null
  - equals
```
public boolean equals(java.lang.Object other)
```
    Is this month-day equal to the specified month-day.
    
    Overrides:
    
    equals in class java.lang.Object
    
    Parameters:
    
    other - the other month-day to compare to, null returns false
    
    Returns:
    
    true if this point is equal to the specified month-day
  - hashCode
```
public int hashCode()
```
    A hash code for this month-day.
    
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    
    a suitable hash code
  - toString
```
public java.lang.String toString()
```
    Outputs this month-day as a String, such as --12-03.
    The output will be in the format --MM-dd:
    
    Overrides:
    
    toString in class java.lang.Object
    
    Returns:
    
    the formatted month-day, never null
  - toString
```
public java.lang.String toString(DateTimeFormatter formatter)
```
    Outputs this month-day as a String using the formatter.
    
    Parameters:
    
    formatter - the formatter to use, not null
    
    Returns:
    
    the formatted month-day string, never null
    
    Throws:
    
    java.lang.UnsupportedOperationException - if the formatter cannot print
    
    CalendricalPrintException - if an error occurs during printing
  - rule
```
public static CalendricalRule<MonthDay> rule()
```
    Gets the rule for the month-day.
    
    Returns:
    
    the rule for the month-day, never null

Class MonthDay

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

serialVersionUID

PARSER

month

day

Constructor Detail

MonthDay

Method Detail

now

now

of

of

of

parse

parse

with

getChronology

get

getMonthOfYear

getDayOfMonth

with

withMonthOfYear

withDayOfMonth

rollMonthOfYear

rollDayOfMonth

matchesCalendrical

adjustDate

adjustDate

isValidYear

atYear

compareTo

isAfter

isBefore

equals

hashCode

toString

toString

rule