Module java.base
Package java.time

Class Year

java.lang.Object
java.time.Year
All Implemented Interfaces:
Serializable, Comparable<Year>, Temporal, TemporalAccessor, TemporalAdjuster
public final class Year extends Object implements Temporal, TemporalAdjuster, Comparable<Year>, Serializable
A year in the ISO-8601 calendar system, such as 2007.

Year is an immutable date-time object that represents a year. Any field that can be derived from a year can be obtained.

Note that years in the ISO chronology only align with years in the Gregorian-Julian system for modern years. Parts of Russia did not switch to the modern Gregorian/ISO rules until 1920. As such, historical years must be treated with caution.

This class does not store or represent a month, day, time or time-zone. For example, the value "2007" can be stored in a Year.

Years represented by this class follow the ISO-8601 standard and use the proleptic numbering system. Year 1 is preceded by year 0, then by year -1.

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 today's rules for leap years are applied for all time. For most applications written today, the ISO-8601 rules are entirely suitable. However, any application that makes use of historical dates, and requires them to be accurate will find the ISO-8601 approach unsuitable.

This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail. The equals method should be used for comparisons.

Implementation Requirements:
This class is immutable and thread-safe.
Since:
1.8
See Also:
Serialized Form

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static int
    MAX_VALUE
    The maximum supported year, '+999,999,999'.
    static int
    MIN_VALUE
    The minimum supported year, '-999,999,999'.

  • Method Summary

    Modifier and Type
    Method
    Description
    Temporal
    adjustInto​(Temporal temporal)
    Adjusts the specified temporal object to have this year.
    LocalDate
    atDay​(int dayOfYear)
    Combines this year with a day-of-year to create a LocalDate.
    YearMonth
    atMonth​(int month)
    Combines this year with a month to create a YearMonth.
    YearMonth
    atMonth​(Month month)
    Combines this year with a month to create a YearMonth.
    LocalDate
    atMonthDay​(MonthDay monthDay)
    Combines this year with a month-day to create a LocalDate.
    int
    compareTo​(Year other)
    Compares this year to another year.
    boolean
    equals​(Object obj)
    Checks if this year is equal to another year.
    String
    format​(DateTimeFormatter formatter)
    Formats this year using the specified formatter.
    static Year
    from​(TemporalAccessor temporal)
    Obtains an instance of Year from a temporal object.
    int
    get​(TemporalField field)
    Gets the value of the specified field from this year as an int.
    long
    getLong​(TemporalField field)
    Gets the value of the specified field from this year as a long.
    int
    getValue()
    Gets the year value.
    int
    hashCode()
    A hash code for this year.
    boolean
    isAfter​(Year other)
    Checks if this year is after the specified year.
    boolean
    isBefore​(Year other)
    Checks if this year is before the specified year.
    boolean
    isLeap()
    Checks if the year is a leap year, according to the ISO proleptic calendar system rules.
    static boolean
    isLeap​(long year)
    Checks if the year is a leap year, according to the ISO proleptic calendar system rules.
    boolean
    isSupported​(TemporalField field)
    Checks if the specified field is supported.
    boolean
    isSupported​(TemporalUnit unit)
    Checks if the specified unit is supported.
    boolean
    isValidMonthDay​(MonthDay monthDay)
    Checks if the month-day is valid for this year.
    int
    length()
    Gets the length of this year in days.
    Year
    minus​(long amountToSubtract, TemporalUnit unit)
    Returns a copy of this year with the specified amount subtracted.
    Year
    minus​(TemporalAmount amountToSubtract)
    Returns a copy of this year with the specified amount subtracted.
    Year
    minusYears​(long yearsToSubtract)
    Returns a copy of this Year with the specified number of years subtracted.
    static Year
    now()
    Obtains the current year from the system clock in the default time-zone.
    static Year
    now​(Clock clock)
    Obtains the current year from the specified clock.
    static Year
    now​(ZoneId zone)
    Obtains the current year from the system clock in the specified time-zone.
    static Year
    of​(int isoYear)
    Obtains an instance of Year.
    static Year
    parse​(CharSequence text)
    Obtains an instance of Year from a text string such as 2007.
    static Year
    parse​(CharSequence text, DateTimeFormatter formatter)
    Obtains an instance of Year from a text string using a specific formatter.
    Year
    plus​(long amountToAdd, TemporalUnit unit)
    Returns a copy of this year with the specified amount added.
    Year
    plus​(TemporalAmount amountToAdd)
    Returns a copy of this year with the specified amount added.
    Year
    plusYears​(long yearsToAdd)
    Returns a copy of this Year with the specified number of years added.
    <R> R
    query​(TemporalQuery<R> query)
    Queries this year using the specified query.
    ValueRange
    range​(TemporalField field)
    Gets the range of valid values for the specified field.
    String
    toString()
    Outputs this year as a String.
    long
    until​(Temporal endExclusive, TemporalUnit unit)
    Calculates the amount of time until another year in terms of the specified unit.
    Year
    with​(TemporalAdjuster adjuster)
    Returns an adjusted copy of this year.
    Year
    with​(TemporalField field, long newValue)
    Returns a copy of this year with the specified field set to a new value.

    Methods declared in class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Field Details

    • MIN_VALUE

      public static final int MIN_VALUE
      The minimum supported year, '-999,999,999'.
      See Also:
      Constant Field Values

    • MAX_VALUE

      public static final int MAX_VALUE
      The maximum supported year, '+999,999,999'.
      See Also:
      Constant Field Values

  • Method Details

    • now

      public static Year now()
      Obtains the current year from the system clock in the default time-zone.

      This will query the system clock in the default time-zone to obtain the current year.

      Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.

      Returns:
      the current year using the system clock and default time-zone, not null

    • now

      public static Year now​(ZoneId zone)
      Obtains the current year from the system clock in the specified time-zone.

      This will query the system clock to obtain the current year. Specifying the time-zone avoids dependence on the default time-zone.

      Using this method will prevent the ability to use an alternate clock for testing because the clock is hard-coded.

      Parameters:
      zone - the zone ID to use, not null
      Returns:
      the current year using the system clock, not null

    • now

      public static Year now​(Clock clock)
      Obtains the current year from the specified clock.

      This will query the specified clock to obtain the current year. 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 year, not null

    • of

      public static Year of​(int isoYear)
      Obtains an instance of Year.

      This method accepts a year value from the proleptic ISO calendar system.

      The year 2AD/CE is represented by 2.
      The year 1AD/CE is represented by 1.
      The year 1BC/BCE is represented by 0.
      The year 2BC/BCE is represented by -1.

      Parameters:
      isoYear - the ISO proleptic year to represent, from MIN_VALUE to MAX_VALUE
      Returns:
      the year, not null
      Throws:
      DateTimeException - if the field is invalid

    • from

      public static Year from​(TemporalAccessor temporal)
      Obtains an instance of Year from a temporal object.

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

      The conversion extracts the 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, Year::from.

      Parameters:
      temporal - the temporal object to convert, not null
      Returns:
      the year, not null
      Throws:
      DateTimeException - if unable to convert to a Year

    • parse

      public static Year parse​(CharSequence text)
      Obtains an instance of Year from a text string such as 2007.

      The string must represent a valid year.

      Parameters:
      text - the text to parse such as "2007", not null
      Returns:
      the parsed year, not null
      Throws:
      DateTimeParseException - if the text cannot be parsed

    • parse

      public static Year parse​(CharSequence text, DateTimeFormatter formatter)
      Obtains an instance of Year from a text string using a specific formatter.

      The text is parsed using the formatter, returning a year.

      Parameters:
      text - the text to parse, not null
      formatter - the formatter to use, not null
      Returns:
      the parsed year, not null
      Throws:
      DateTimeParseException - if the text cannot be parsed

    • isLeap

      public static boolean isLeap​(long year)
      Checks if the year is a leap year, according to the ISO proleptic calendar system rules.

      This method applies the current rules for leap years across the whole time-line. In general, a year is a leap year if it is divisible by four without remainder. However, years divisible by 100, are not leap years, with the exception of years divisible by 400 which are.

      For example, 1904 is a leap year it is divisible by 4. 1900 was not a leap year as it is divisible by 100, however 2000 was a leap year as it is divisible by 400.

      The calculation is proleptic - applying the same rules into the far future and far past. This is historically inaccurate, but is correct for the ISO-8601 standard.

      Parameters:
      year - the year to check
      Returns:
      true if the year is leap, false otherwise

    • getValue

      public int getValue()
      Gets the year value.

      The year returned by this method is proleptic as per get(YEAR).

      Returns:
      the year, MIN_VALUE to MAX_VALUE

    • isSupported

      public boolean isSupported​(TemporalField field)
      Checks if the specified field is supported.

      This checks if this year can be queried for the specified field. If false, then calling the range, get and with(TemporalField, long) methods will throw an exception.

      If the field is a ChronoField then the query is implemented here. The supported fields are:

      • YEAR_OF_ERA
      • YEAR
      • ERA
      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.

      Specified by:
      isSupported in interface TemporalAccessor
      Parameters:
      field - the field to check, null returns false
      Returns:
      true if the field is supported on this year, false if not

    • isSupported

      public boolean isSupported​(TemporalUnit unit)
      Checks if the specified unit is supported.

      This checks if the specified unit can be added to, or subtracted from, this year. If false, then calling the plus(long, TemporalUnit) and minus methods will throw an exception.

      If the unit is a ChronoUnit then the query is implemented here. The supported units are:

      • YEARS
      • DECADES
      • CENTURIES
      • MILLENNIA
      • ERAS
      All other ChronoUnit instances will return false.

      If the unit is not a ChronoUnit, then the result of this method is obtained by invoking TemporalUnit.isSupportedBy(Temporal) passing this as the argument. Whether the unit is supported is determined by the unit.

      Specified by:
      isSupported in interface Temporal
      Parameters:
      unit - the unit to check, null returns false
      Returns:
      true if the unit can be added/subtracted, false if not

    • range

      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 year 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 a ChronoField then the query is implemented here. The supported fields will return appropriate range instances. 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.

      Specified by:
      range in interface TemporalAccessor
      Parameters:
      field - the field to query the range for, not null
      Returns:
      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

    • get

      public int get​(TemporalField field)
      Gets the value of the specified field from this year as an int.

      This queries this year 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 a ChronoField then the query is implemented here. The supported fields will return valid values based on this year. 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.

      Specified by:
      get in interface TemporalAccessor
      Parameters:
      field - the field to get, not null
      Returns:
      the value for the field
      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

    • getLong

      public long getLong​(TemporalField field)
      Gets the value of the specified field from this year as a long.

      This queries this year 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 a ChronoField then the query is implemented here. The supported fields will return valid values based on this year. 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.

      Specified by:
      getLong in interface TemporalAccessor
      Parameters:
      field - the field to get, not null
      Returns:
      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

    • isLeap

      public boolean isLeap()
      Checks if the year is a leap year, according to the ISO proleptic calendar system rules.

      This method applies the current rules for leap years across the whole time-line. In general, a year is a leap year if it is divisible by four without remainder. However, years divisible by 100, are not leap years, with the exception of years divisible by 400 which are.

      For example, 1904 is a leap year it is divisible by 4. 1900 was not a leap year as it is divisible by 100, however 2000 was a leap year as it is divisible by 400.

      The calculation is proleptic - applying the same rules into the far future and far past. This is historically inaccurate, but is correct for the ISO-8601 standard.

      Returns:
      true if the year is leap, false otherwise

    • isValidMonthDay

      public boolean isValidMonthDay​(MonthDay monthDay)
      Checks if the month-day is valid for this year.

      This method checks whether this year and the input month and day form a valid date.

      Parameters:
      monthDay - the month-day to validate, null returns false
      Returns:
      true if the month and day are valid for this year

    • length

      public int length()
      Gets the length of this year in days.
      Returns:
      the length of this year in days, 365 or 366

    • with

      public Year with​(TemporalAdjuster adjuster)
      Returns an adjusted copy of this year.

      This returns a Year, based on this one, with the year adjusted. The adjustment takes place using the specified adjuster strategy object. Read the documentation of the adjuster to understand what adjustment will be made.

      The result of this method is obtained by invoking the TemporalAdjuster.adjustInto(Temporal) method on the specified adjuster passing this as the argument.

      This instance is immutable and unaffected by this method call.

      Specified by:
      with in interface Temporal
      Parameters:
      adjuster - the adjuster to use, not null
      Returns:
      a Year based on this with the adjustment made, not null
      Throws:
      DateTimeException - if the adjustment cannot be made
      ArithmeticException - if numeric overflow occurs

    • with

      public Year with​(TemporalField field, long newValue)
      Returns a copy of this year with the specified field set to a new value.

      This returns a Year, based on this one, with the value for the specified field changed. If it is not possible to set the value, because the field is not supported or for some other reason, an exception is thrown.

      If the field is a ChronoField then the adjustment is implemented here. The supported fields behave as follows:

      • YEAR_OF_ERA - Returns a Year with the specified year-of-era The era will be unchanged.
      • YEAR - Returns a Year with the specified year. This completely replaces the date and is equivalent to of(int).
      • ERA - Returns a Year with the specified era. The year-of-era will be unchanged.

      In all cases, if the new value is outside the valid range of values for the field then a DateTimeException will be thrown.

      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.adjustInto(Temporal, long) passing this as the argument. In this case, the field determines whether and how to adjust the instant.

      This instance is immutable and unaffected by this method call.

      Specified by:
      with in interface Temporal
      Parameters:
      field - the field to set in the result, not null
      newValue - the new value of the field in the result
      Returns:
      a Year based on this with the specified field set, not null
      Throws:
      DateTimeException - if the field cannot be set
      UnsupportedTemporalTypeException - if the field is not supported
      ArithmeticException - if numeric overflow occurs

    • plus

      public Year plus​(TemporalAmount amountToAdd)
      Returns a copy of this year with the specified amount added.

      This returns a Year, based on this one, with the specified amount added. The amount is typically Period but may be any other type implementing the TemporalAmount interface.

      The calculation is delegated to the amount object by calling TemporalAmount.addTo(Temporal). The amount implementation is free to implement the addition in any way it wishes, however it typically calls back to plus(long, TemporalUnit). Consult the documentation of the amount implementation to determine if it can be successfully added.

      This instance is immutable and unaffected by this method call.

      Specified by:
      plus in interface Temporal
      Parameters:
      amountToAdd - the amount to add, not null
      Returns:
      a Year based on this year with the addition made, not null
      Throws:
      DateTimeException - if the addition cannot be made
      ArithmeticException - if numeric overflow occurs

    • plus

      public Year plus​(long amountToAdd, TemporalUnit unit)
      Returns a copy of this year with the specified amount added.

      This returns a Year, based on this one, with the amount in terms of the unit added. If it is not possible to add the amount, because the unit is not supported or for some other reason, an exception is thrown.

      If the field is a ChronoUnit then the addition is implemented here. The supported fields behave as follows:

      • YEARS - Returns a Year with the specified number of years added. This is equivalent to plusYears(long).
      • DECADES - Returns a Year with the specified number of decades added. This is equivalent to calling plusYears(long) with the amount multiplied by 10.
      • CENTURIES - Returns a Year with the specified number of centuries added. This is equivalent to calling plusYears(long) with the amount multiplied by 100.
      • MILLENNIA - Returns a Year with the specified number of millennia added. This is equivalent to calling plusYears(long) with the amount multiplied by 1,000.
      • ERAS - Returns a Year with the specified number of eras added. Only two eras are supported so the amount must be one, zero or minus one. If the amount is non-zero then the year is changed such that the year-of-era is unchanged.

      All other ChronoUnit instances will throw an UnsupportedTemporalTypeException.

      If the field is not a ChronoUnit, then the result of this method is obtained by invoking TemporalUnit.addTo(Temporal, long) passing this as the argument. In this case, the unit determines whether and how to perform the addition.

      This instance is immutable and unaffected by this method call.

      Specified by:
      plus in interface Temporal
      Parameters:
      amountToAdd - the amount of the unit to add to the result, may be negative
      unit - the unit of the amount to add, not null
      Returns:
      a Year based on this year with the specified amount added, not null
      Throws:
      DateTimeException - if the addition cannot be made
      UnsupportedTemporalTypeException - if the unit is not supported
      ArithmeticException - if numeric overflow occurs

    • plusYears

      public Year plusYears​(long yearsToAdd)
      Returns a copy of this Year with the specified number of years added.

      This instance is immutable and unaffected by this method call.

      Parameters:
      yearsToAdd - the years to add, may be negative
      Returns:
      a Year based on this year with the years added, not null
      Throws:
      DateTimeException - if the result exceeds the supported range

    • minus

      public Year minus​(TemporalAmount amountToSubtract)
      Returns a copy of this year with the specified amount subtracted.

      This returns a Year, based on this one, with the specified amount subtracted. The amount is typically Period but may be any other type implementing the TemporalAmount interface.

      The calculation is delegated to the amount object by calling TemporalAmount.subtractFrom(Temporal). The amount implementation is free to implement the subtraction in any way it wishes, however it typically calls back to minus(long, TemporalUnit). Consult the documentation of the amount implementation to determine if it can be successfully subtracted.

      This instance is immutable and unaffected by this method call.

      Specified by:
      minus in interface Temporal
      Parameters:
      amountToSubtract - the amount to subtract, not null
      Returns:
      a Year based on this year with the subtraction made, not null
      Throws:
      DateTimeException - if the subtraction cannot be made
      ArithmeticException - if numeric overflow occurs

    • minus

      public Year minus​(long amountToSubtract, TemporalUnit unit)
      Returns a copy of this year with the specified amount subtracted.

      This returns a Year, based on this one, with the amount in terms of the unit subtracted. If it is not possible to subtract the amount, because the unit is not supported or for some other reason, an exception is thrown.

      This method is equivalent to plus(long, TemporalUnit) with the amount negated. See that method for a full description of how addition, and thus subtraction, works.

      This instance is immutable and unaffected by this method call.

      Specified by:
      minus in interface Temporal
      Parameters:
      amountToSubtract - the amount of the unit to subtract from the result, may be negative
      unit - the unit of the amount to subtract, not null
      Returns:
      a Year based on this year with the specified amount subtracted, not null
      Throws:
      DateTimeException - if the subtraction cannot be made
      UnsupportedTemporalTypeException - if the unit is not supported
      ArithmeticException - if numeric overflow occurs

    • minusYears

      public Year minusYears​(long yearsToSubtract)
      Returns a copy of this Year with the specified number of years subtracted.

      This instance is immutable and unaffected by this method call.

      Parameters:
      yearsToSubtract - the years to subtract, may be negative
      Returns:
      a Year based on this year with the year subtracted, not null
      Throws:
      DateTimeException - if the result exceeds the supported range

    • query

      public <R> R query​(TemporalQuery<R> query)
      Queries this year using the specified query.

      This queries this 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.

      Specified by:
      query in interface TemporalAccessor
      Type Parameters:
      R - the type of the result
      Parameters:
      query - the query to invoke, not null
      Returns:
      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)

    • adjustInto

      public Temporal adjustInto​(Temporal temporal)
      Adjusts the specified temporal object to have this year.

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

      The adjustment is equivalent to using Temporal.with(TemporalField, long) passing ChronoField.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 = thisYear.adjustInto(temporal);
   temporal = temporal.with(thisYear);

      This instance is immutable and unaffected by this method call.

      Specified by:
      adjustInto in interface TemporalAdjuster
      Parameters:
      temporal - the target object to be adjusted, not null
      Returns:
      the adjusted object, not null
      Throws:
      DateTimeException - if unable to make the adjustment
      ArithmeticException - if numeric overflow occurs

    • until

      public long until​(Temporal endExclusive, TemporalUnit unit)
      Calculates the amount of time until another year in terms of the specified unit.

      This calculates the amount of time between two Year objects in terms of a single TemporalUnit. The start and end points are this and the specified year. The result will be negative if the end is before the start. The Temporal passed to this method is converted to a Year using from(TemporalAccessor). For example, the amount in decades between two year can be calculated using startYear.until(endYear, DECADES).

      The calculation returns a whole number, representing the number of complete units between the two years. For example, the amount in decades between 2012 and 2031 will only be one decade as it is one year short of two decades.

      There are two equivalent ways of using this method. The first is to invoke this method. The second is to use TemporalUnit.between(Temporal, Temporal): 

         // these two lines are equivalent
   amount = start.until(end, YEARS);
   amount = YEARS.between(start, end);
      The choice should be made based on which makes the code more readable.

      The calculation is implemented in this method for ChronoUnit. The units YEARS, DECADES, CENTURIES, MILLENNIA and ERAS are supported. Other ChronoUnit values will throw an exception.

      If the unit is not a ChronoUnit, then the result of this method is obtained by invoking TemporalUnit.between(Temporal, Temporal) passing this as the first argument and the converted input temporal as the second argument.

      This instance is immutable and unaffected by this method call.

      Specified by:
      until in interface Temporal
      Parameters:
      endExclusive - the end date, exclusive, which is converted to a Year, not null
      unit - the unit to measure the amount in, not null
      Returns:
      the amount of time between this year and the end year
      Throws:
      DateTimeException - if the amount cannot be calculated, or the end temporal cannot be converted to a Year
      UnsupportedTemporalTypeException - if the unit is not supported
      ArithmeticException - if numeric overflow occurs

    • format

      public String format​(DateTimeFormatter formatter)
      Formats this year using the specified formatter.

      This year will be passed to the formatter to produce a string.

      Parameters:
      formatter - the formatter to use, not null
      Returns:
      the formatted year string, not null
      Throws:
      DateTimeException - if an error occurs during printing

    • atDay

      public LocalDate atDay​(int dayOfYear)
      Combines this year with a day-of-year to create a LocalDate.

      This returns a LocalDate formed from this year and the specified day-of-year.

      The day-of-year value 366 is only valid in a leap year.

      Parameters:
      dayOfYear - the day-of-year to use, from 1 to 365-366
      Returns:
      the local date formed from this year and the specified date of year, not null
      Throws:
      DateTimeException - if the day of year is zero or less, 366 or greater or equal to 366 and this is not a leap year

    • atMonth

      public YearMonth atMonth​(Month month)
      Combines this year with a month to create a YearMonth.

      This returns a YearMonth formed from this year and the specified month. All possible combinations of year and month are valid.

      This method can be used as part of a chain to produce a date: 

        LocalDate date = year.atMonth(month).atDay(day);
      Parameters:
      month - the month-of-year to use, not null
      Returns:
      the year-month formed from this year and the specified month, not null

    • atMonth

      public YearMonth atMonth​(int month)
      Combines this year with a month to create a YearMonth.

      This returns a YearMonth formed from this year and the specified month. All possible combinations of year and month are valid.

      This method can be used as part of a chain to produce a date: 

        LocalDate date = year.atMonth(month).atDay(day);
      Parameters:
      month - the month-of-year to use, from 1 (January) to 12 (December)
      Returns:
      the year-month formed from this year and the specified month, not null
      Throws:
      DateTimeException - if the month is invalid

    • atMonthDay

      public LocalDate atMonthDay​(MonthDay monthDay)
      Combines this year with a month-day to create a LocalDate.

      This returns a LocalDate formed from this year and the specified month-day.

      A month-day of February 29th will be adjusted to February 28th in the resulting date if the year is not a leap year.

      Parameters:
      monthDay - the month-day to use, not null
      Returns:
      the local date formed from this year and the specified month-day, not null

    • compareTo

      public int compareTo​(Year other)
      Compares this year to another year.

      The comparison is based on the value of the year. It is "consistent with equals", as defined by Comparable.

      Specified by:
      compareTo in interface Comparable<Year>
      Parameters:
      other - the other year to compare to, not null
      Returns:
      the comparator value, negative if less, positive if greater

    • isAfter

      public boolean isAfter​(Year other)
      Checks if this year is after the specified year.
      Parameters:
      other - the other year to compare to, not null
      Returns:
      true if this is after the specified year

    • isBefore

      public boolean isBefore​(Year other)
      Checks if this year is before the specified year.
      Parameters:
      other - the other year to compare to, not null
      Returns:
      true if this point is before the specified year

    • equals

      public boolean equals​(Object obj)
      Checks if this year is equal to another year.

      The comparison is based on the time-line position of the years.

      Overrides:
      equals in class Object
      Parameters:
      obj - the object to check, null returns false
      Returns:
      true if this is equal to the other year
      See Also:
      Object.hashCode(), HashMap

    • hashCode

      public int hashCode()
      A hash code for this year.
      Overrides:
      hashCode in class Object
      Returns:
      a suitable hash code
      See Also:
      Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

    • toString

      public String toString()
      Outputs this year as a String.
      Overrides:
      toString in class Object
      Returns:
      a string representation of this year, not null