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Month

public final enum Month
extends Enum<Month> implements TemporalAccessor, TemporalAdjuster

java.lang.Object
   ↳ java.lang.Enum<java.time.Month>
     ↳ java.time.Month


A month-of-year, such as 'July'.

Month is an enum representing the 12 months of the year - January, February, March, April, May, June, July, August, September, October, November and December.

In addition to the textual enum name, each month-of-year has an int value. The int value follows normal usage and the ISO-8601 standard, from 1 (January) to 12 (December). It is recommended that applications use the enum rather than the int value to ensure code clarity.

Do not use ordinal() to obtain the numeric representation of Month. Use getValue() instead.

This enum represents a common concept that is found in many calendar systems. As such, this enum may be used by any calendar system that has the month-of-year concept defined exactly equivalent to the ISO-8601 calendar system.

Summary

Enum values

Month  APRIL

The singleton instance for the month of April with 30 days. 

Month  AUGUST

The singleton instance for the month of August with 31 days. 

Month  DECEMBER

The singleton instance for the month of December with 31 days. 

Month  FEBRUARY

The singleton instance for the month of February with 28 days, or 29 in a leap year. 

Month  JANUARY

The singleton instance for the month of January with 31 days. 

Month  JULY

The singleton instance for the month of July with 31 days. 

Month  JUNE

The singleton instance for the month of June with 30 days. 

Month  MARCH

The singleton instance for the month of March with 31 days. 

Month  MAY

The singleton instance for the month of May with 31 days. 

Month  NOVEMBER

The singleton instance for the month of November with 30 days. 

Month  OCTOBER

The singleton instance for the month of October with 31 days. 

Month  SEPTEMBER

The singleton instance for the month of September with 30 days. 

Public methods

Temporal adjustInto(Temporal temporal)

Adjusts the specified temporal object to have this month-of-year.

int firstDayOfYear(boolean leapYear)

Gets the day-of-year corresponding to the first day of this month.

Month firstMonthOfQuarter()

Gets the month corresponding to the first month of this quarter.

static Month from(TemporalAccessor temporal)

Obtains an instance of Month from a temporal object.

int get(TemporalField field)

Gets the value of the specified field from this month-of-year as an int.

String getDisplayName(TextStyle style, Locale locale)

Gets the textual representation, such as 'Jan' or 'December'.

long getLong(TemporalField field)

Gets the value of the specified field from this month-of-year as a long.

int getValue()

Gets the month-of-year int value.

boolean isSupported(TemporalField field)

Checks if the specified field is supported.

int length(boolean leapYear)

Gets the length of this month in days.

int maxLength()

Gets the maximum length of this month in days.

int minLength()

Gets the minimum length of this month in days.

Month minus(long months)

Returns the month-of-year that is the specified number of months before this one.

static Month of(int month)

Obtains an instance of Month from an int value.

Month plus(long months)

Returns the month-of-year that is the specified number of quarters after this one.

<R> R query(TemporalQuery<R> query)

Queries this month-of-year using the specified query.

ValueRange range(TemporalField field)

Gets the range of valid values for the specified field.

static Month valueOf(String name)
static final Month[] values()

Inherited methods

Enum values

APRIL

added in API level 26
public static final Month APRIL

The singleton instance for the month of April with 30 days. This has the numeric value of 4.

AUGUST

added in API level 26
public static final Month AUGUST

The singleton instance for the month of August with 31 days. This has the numeric value of 8.

DECEMBER

added in API level 26
public static final Month DECEMBER

The singleton instance for the month of December with 31 days. This has the numeric value of 12.

FEBRUARY

added in API level 26
public static final Month FEBRUARY

The singleton instance for the month of February with 28 days, or 29 in a leap year. This has the numeric value of 2.

JANUARY

added in API level 26
public static final Month JANUARY

The singleton instance for the month of January with 31 days. This has the numeric value of 1.

JULY

added in API level 26
public static final Month JULY

The singleton instance for the month of July with 31 days. This has the numeric value of 7.

JUNE

added in API level 26
public static final Month JUNE

The singleton instance for the month of June with 30 days. This has the numeric value of 6.

MARCH

added in API level 26
public static final Month MARCH

The singleton instance for the month of March with 31 days. This has the numeric value of 3.

MAY

added in API level 26
public static final Month MAY

The singleton instance for the month of May with 31 days. This has the numeric value of 5.

NOVEMBER

added in API level 26
public static final Month NOVEMBER

The singleton instance for the month of November with 30 days. This has the numeric value of 11.

OCTOBER

added in API level 26
public static final Month OCTOBER

The singleton instance for the month of October with 31 days. This has the numeric value of 10.

SEPTEMBER

added in API level 26
public static final Month SEPTEMBER

The singleton instance for the month of September with 30 days. This has the numeric value of 9.

Public methods

adjustInto

added in API level 26
public Temporal adjustInto (Temporal temporal)

Adjusts the specified temporal object to have this month-of-year.

This returns a temporal object of the same observable type as the input with the month-of-year changed to be the same as this.

The adjustment is equivalent to using Temporal.with(TemporalField, long) passing ChronoField.MONTH_OF_YEAR as the field. If the specified temporal object does not use the ISO calendar system then a DateTimeException is thrown.

In most cases, it is clearer to reverse the calling pattern by using Temporal.with(TemporalAdjuster):

   // these two lines are equivalent, but the second approach is recommended
   temporal = thisMonth.adjustInto(temporal);
   temporal = temporal.with(thisMonth);
 

For example, given a date in May, the following are output:

   dateInMay.with(JANUARY);    // four months earlier
   dateInMay.with(APRIL);      // one months earlier
   dateInMay.with(MAY);        // same date
   dateInMay.with(JUNE);       // one month later
   dateInMay.with(DECEMBER);   // seven months later
 

This instance is immutable and unaffected by this method call.

Parameters
temporal Temporal: the target object to be adjusted, not null

Returns
Temporal the adjusted object, not null

Throws
DateTimeException if unable to make the adjustment
ArithmeticException if numeric overflow occurs

firstDayOfYear

added in API level 26
public int firstDayOfYear (boolean leapYear)

Gets the day-of-year corresponding to the first day of this month.

This returns the day-of-year that this month begins on, using the leap year flag to determine the length of February.

Parameters
leapYear boolean: true if the length is required for a leap year

Returns
int the day of year corresponding to the first day of this month, from 1 to 336

firstMonthOfQuarter

added in API level 26
public Month firstMonthOfQuarter ()

Gets the month corresponding to the first month of this quarter.

The year can be divided into four quarters. This method returns the first month of the quarter for the base month. January, February and March return January. April, May and June return April. July, August and September return July. October, November and December return October.

Returns
Month the first month of the quarter corresponding to this month, not null

from

added in API level 26
public static Month from (TemporalAccessor temporal)

Obtains an instance of Month from a temporal object.

This obtains a month based on the specified temporal. A TemporalAccessor represents an arbitrary set of date and time information, which this factory converts to an instance of Month.

The conversion extracts the MONTH_OF_YEAR field. The extraction is only permitted if the temporal object has an ISO chronology, or can be converted to a LocalDate.

This method matches the signature of the functional interface TemporalQuery allowing it to be used as a query via method reference, Month::from.

Parameters
temporal TemporalAccessor: the temporal object to convert, not null

Returns
Month the month-of-year, not null

Throws
DateTimeException if unable to convert to a Month

get

added in API level 26
public int get (TemporalField field)

Gets the value of the specified field from this month-of-year as an int.

This queries this month for the value of the specified field. The returned value will always be within the valid range of values for the field. If it is not possible to return the value, because the field is not supported or for some other reason, an exception is thrown.

If the field is MONTH_OF_YEAR then the value of the month-of-year, from 1 to 12, will be returned. All other ChronoField instances will throw an UnsupportedTemporalTypeException.

If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.getFrom(TemporalAccessor) passing this as the argument. Whether the value can be obtained, and what the value represents, is determined by the field.

Parameters
field TemporalField: the field to get, not null

Returns
int the value for the field, within the valid range of values

Throws
DateTimeException if a value for the field cannot be obtained or the value is outside the range of valid values for the field
UnsupportedTemporalTypeException if the field is not supported or the range of values exceeds an int
ArithmeticException if numeric overflow occurs

getDisplayName

added in API level 26
public String getDisplayName (TextStyle style, 
                Locale locale)

Gets the textual representation, such as 'Jan' or 'December'.

This returns the textual name used to identify the month-of-year, suitable for presentation to the user. The parameters control the style of the returned text and the locale.

If no textual mapping is found then the numeric value is returned.

Parameters
style TextStyle: the length of the text required, not null

locale Locale: the locale to use, not null

Returns
String the text value of the month-of-year, not null

getLong

added in API level 26
public long getLong (TemporalField field)

Gets the value of the specified field from this month-of-year as a long.

This queries this month for the value of the specified field. If it is not possible to return the value, because the field is not supported or for some other reason, an exception is thrown.

If the field is MONTH_OF_YEAR then the value of the month-of-year, from 1 to 12, will be returned. All other ChronoField instances will throw an UnsupportedTemporalTypeException.

If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.getFrom(TemporalAccessor) passing this as the argument. Whether the value can be obtained, and what the value represents, is determined by the field.

Parameters
field TemporalField: the field to get, not null

Returns
long the value for the field

Throws
DateTimeException if a value for the field cannot be obtained
UnsupportedTemporalTypeException if the field is not supported
ArithmeticException if numeric overflow occurs

getValue

added in API level 26
public int getValue ()

Gets the month-of-year int value.

The values are numbered following the ISO-8601 standard, from 1 (January) to 12 (December).

Returns
int the month-of-year, from 1 (January) to 12 (December)

isSupported

added in API level 26
public boolean isSupported (TemporalField field)

Checks if the specified field is supported.

This checks if this month-of-year can be queried for the specified field. If false, then calling the range and get methods will throw an exception.

If the field is MONTH_OF_YEAR then this method returns true. All other ChronoField instances will return false.

If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.isSupportedBy(TemporalAccessor) passing this as the argument. Whether the field is supported is determined by the field.

Parameters
field TemporalField: the field to check, null returns false

Returns
boolean true if the field is supported on this month-of-year, false if not

length

added in API level 26
public int length (boolean leapYear)

Gets the length of this month in days.

This takes a flag to determine whether to return the length for a leap year or not.

February has 28 days in a standard year and 29 days in a leap year. April, June, September and November have 30 days. All other months have 31 days.

Parameters
leapYear boolean: true if the length is required for a leap year

Returns
int the length of this month in days, from 28 to 31

maxLength

added in API level 26
public int maxLength ()

Gets the maximum length of this month in days.

February has a maximum length of 29 days. April, June, September and November have 30 days. All other months have 31 days.

Returns
int the maximum length of this month in days, from 29 to 31

minLength

added in API level 26
public int minLength ()

Gets the minimum length of this month in days.

February has a minimum length of 28 days. April, June, September and November have 30 days. All other months have 31 days.

Returns
int the minimum length of this month in days, from 28 to 31

minus

added in API level 26
public Month minus (long months)

Returns the month-of-year that is the specified number of months before this one.

The calculation rolls around the start of the year from January to December. The specified period may be negative.

This instance is immutable and unaffected by this method call.

Parameters
months long: the months to subtract, positive or negative

Returns
Month the resulting month, not null

of

added in API level 26
public static Month of (int month)

Obtains an instance of Month from an int value.

Month is an enum representing the 12 months of the year. This factory allows the enum to be obtained from the int value. The int value follows the ISO-8601 standard, from 1 (January) to 12 (December).

Parameters
month int: the month-of-year to represent, from 1 (January) to 12 (December)

Returns
Month the month-of-year, not null

Throws
DateTimeException if the month-of-year is invalid

plus

added in API level 26
public Month plus (long months)

Returns the month-of-year that is the specified number of quarters after this one.

The calculation rolls around the end of the year from December to January. The specified period may be negative.

This instance is immutable and unaffected by this method call.

Parameters
months long: the months to add, positive or negative

Returns
Month the resulting month, not null

query

added in API level 26
public R query (TemporalQuery<R> query)

Queries this month-of-year using the specified query.

This queries this month-of-year using the specified query strategy object. The TemporalQuery object defines the logic to be used to obtain the result. Read the documentation of the query to understand what the result of this method will be.

The result of this method is obtained by invoking the TemporalQuery.queryFrom(TemporalAccessor) method on the specified query passing this as the argument.

Parameters
query TemporalQuery: the query to invoke, not null

Returns
R the query result, null may be returned (defined by the query)

Throws
DateTimeException if unable to query (defined by the query)
ArithmeticException if numeric overflow occurs (defined by the query)

range

added in API level 26
public ValueRange range (TemporalField field)

Gets the range of valid values for the specified field.

The range object expresses the minimum and maximum valid values for a field. This month is used to enhance the accuracy of the returned range. If it is not possible to return the range, because the field is not supported or for some other reason, an exception is thrown.

If the field is MONTH_OF_YEAR then the range of the month-of-year, from 1 to 12, will be returned. All other ChronoField instances will throw an UnsupportedTemporalTypeException.

If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessor) passing this as the argument. Whether the range can be obtained is determined by the field.

Parameters
field TemporalField: the field to query the range for, not null

Returns
ValueRange the range of valid values for the field, not null

Throws
DateTimeException if the range for the field cannot be obtained
UnsupportedTemporalTypeException if the field is not supported

valueOf

added in API level 26
public static Month valueOf (String name)

Parameters
name String

Returns
Month

values

added in API level 26
public static final Month[] values ()

Returns
Month[]