Package org.joda.time

Class Days

All Implemented Interfaces:
Serializable, Comparable<BaseSingleFieldPeriod>, ReadablePeriod

public final class Days extends BaseSingleFieldPeriod
An immutable time period representing a number of days.

Days is an immutable period that can only store days. It does not store years, months or hours for example. As such it is a type-safe way of representing a number of days in an application.

The number of days is set in the constructor, and may be queried using getDays(). Basic mathematical operations are provided - plus(), minus(), multipliedBy() and dividedBy().

Days is thread-safe and immutable.

Since:
1.4
Author:
Stephen Colebourne
See Also:
  • Field Details

    • ZERO

      public static final Days ZERO
      Constant representing zero days.
    • ONE

      public static final Days ONE
      Constant representing one day.
    • TWO

      public static final Days TWO
      Constant representing two days.
    • THREE

      public static final Days THREE
      Constant representing three days.
    • FOUR

      public static final Days FOUR
      Constant representing four days.
    • FIVE

      public static final Days FIVE
      Constant representing five days.
    • SIX

      public static final Days SIX
      Constant representing six days.
    • SEVEN

      public static final Days SEVEN
      Constant representing seven days.
    • MAX_VALUE

      public static final Days MAX_VALUE
      Constant representing the maximum number of days that can be stored in this object.
    • MIN_VALUE

      public static final Days MIN_VALUE
      Constant representing the minimum number of days that can be stored in this object.
  • Method Details

    • days

      public static Days days(int days)
      Obtains an instance of Days that may be cached. Days is immutable, so instances can be cached and shared. This factory method provides access to shared instances.
      Parameters:
      days - the number of days to obtain an instance for
      Returns:
      the instance of Days
    • daysBetween

      public static Days daysBetween(ReadableInstant start, ReadableInstant end)
      Creates a Days representing the number of whole days between the two specified datetimes. This method correctly handles any daylight savings time changes that may occur during the interval.
      Parameters:
      start - the start instant, must not be null
      end - the end instant, must not be null
      Returns:
      the period in days
      Throws:
      IllegalArgumentException - if the instants are null or invalid
    • daysBetween

      public static Days daysBetween(ReadablePartial start, ReadablePartial end)
      Creates a Days representing the number of whole days between the two specified partial datetimes.

      The two partials must contain the same fields, for example you can specify two LocalDate objects.

      Parameters:
      start - the start partial date, must not be null
      end - the end partial date, must not be null
      Returns:
      the period in days
      Throws:
      IllegalArgumentException - if the partials are null or invalid
    • daysIn

      public static Days daysIn(ReadableInterval interval)
      Creates a Days representing the number of whole days in the specified interval. This method correctly handles any daylight savings time changes that may occur during the interval.
      Parameters:
      interval - the interval to extract days from, null returns zero
      Returns:
      the period in days
      Throws:
      IllegalArgumentException - if the partials are null or invalid
    • standardDaysIn

      public static Days standardDaysIn(ReadablePeriod period)
      Creates a new Days representing the number of complete standard length days in the specified period.

      This factory method converts all fields from the period to hours using standardised durations for each field. Only those fields which have a precise duration in the ISO UTC chronology can be converted.

      • One week consists of 7 days.
      • One day consists of 24 hours.
      • One hour consists of 60 minutes.
      • One minute consists of 60 seconds.
      • One second consists of 1000 milliseconds.
      Months and Years are imprecise and periods containing these values cannot be converted.
      Parameters:
      period - the period to get the number of hours from, null returns zero
      Returns:
      the period in days
      Throws:
      IllegalArgumentException - if the period contains imprecise duration values
    • parseDays

      public static Days parseDays(String periodStr)
      Creates a new Days by parsing a string in the ISO8601 format 'PnD'.

      The parse will accept the full ISO syntax of PnYnMnWnDTnHnMnS however only the days component may be non-zero. If any other component is non-zero, an exception will be thrown.

      Parameters:
      periodStr - the period string, null returns zero
      Returns:
      the period in days
      Throws:
      IllegalArgumentException - if the string format is invalid
    • getFieldType

      public DurationFieldType getFieldType()
      Gets the duration field type, which is days.
      Specified by:
      getFieldType in class BaseSingleFieldPeriod
      Returns:
      the period type
    • getPeriodType

      public PeriodType getPeriodType()
      Gets the period type, which is days.
      Specified by:
      getPeriodType in interface ReadablePeriod
      Specified by:
      getPeriodType in class BaseSingleFieldPeriod
      Returns:
      the period type
    • toStandardWeeks

      public Weeks toStandardWeeks()
      Converts this period in days to a period in weeks assuming a 7 day week.

      This method allows you to convert between different types of period. However to achieve this it makes the assumption that all weeks are 7 days long. This may not be true for some unusual chronologies. However, it is included as it is a useful operation for many applications and business rules.

      Returns:
      a period representing the number of weeks for this number of days
    • toStandardHours

      public Hours toStandardHours()
      Converts this period in days to a period in hours assuming a 24 hour day.

      This method allows you to convert between different types of period. However to achieve this it makes the assumption that all days are 24 hours long. This is not true when daylight savings is considered and may also not be true for some unusual chronologies. However, it is included as it is a useful operation for many applications and business rules.

      Returns:
      a period representing the number of hours for this number of days
      Throws:
      ArithmeticException - if the number of hours is too large to be represented
    • toStandardMinutes

      public Minutes toStandardMinutes()
      Converts this period in days to a period in minutes assuming a 24 hour day and 60 minute hour.

      This method allows you to convert between different types of period. However to achieve this it makes the assumption that all days are 24 hours long and all hours are 60 minutes long. This is not true when daylight savings is considered and may also not be true for some unusual chronologies. However, it is included as it is a useful operation for many applications and business rules.

      Returns:
      a period representing the number of minutes for this number of days
      Throws:
      ArithmeticException - if the number of minutes is too large to be represented
    • toStandardSeconds

      public Seconds toStandardSeconds()
      Converts this period in days to a period in seconds assuming a 24 hour day, 60 minute hour and 60 second minute.

      This method allows you to convert between different types of period. However to achieve this it makes the assumption that all days are 24 hours long, all hours are 60 minutes long and all minutes are 60 seconds long. This is not true when daylight savings is considered and may also not be true for some unusual chronologies. However, it is included as it is a useful operation for many applications and business rules.

      Returns:
      a period representing the number of seconds for this number of days
      Throws:
      ArithmeticException - if the number of seconds is too large to be represented
    • toStandardDuration

      public Duration toStandardDuration()
      Converts this period in days to a duration in milliseconds assuming a 24 hour day, 60 minute hour and 60 second minute.

      This method allows you to convert from a period to a duration. However to achieve this it makes the assumption that all days are 24 hours long, all hours are 60 minutes and all minutes are 60 seconds. This is not true when daylight savings time is considered, and may also not be true for some unusual chronologies. However, it is included as it is a useful operation for many applications and business rules.

      Returns:
      a duration equivalent to this number of days
    • getDays

      public int getDays()
      Gets the number of days that this period represents.
      Returns:
      the number of days in the period
    • plus

      public Days plus(int days)
      Returns a new instance with the specified number of days added.

      This instance is immutable and unaffected by this method call.

      Parameters:
      days - the amount of days to add, may be negative
      Returns:
      the new period plus the specified number of days
      Throws:
      ArithmeticException - if the result overflows an int
    • plus

      public Days plus(Days days)
      Returns a new instance with the specified number of days added.

      This instance is immutable and unaffected by this method call.

      Parameters:
      days - the amount of days to add, may be negative, null means zero
      Returns:
      the new period plus the specified number of days
      Throws:
      ArithmeticException - if the result overflows an int
    • minus

      public Days minus(int days)
      Returns a new instance with the specified number of days taken away.

      This instance is immutable and unaffected by this method call.

      Parameters:
      days - the amount of days to take away, may be negative
      Returns:
      the new period minus the specified number of days
      Throws:
      ArithmeticException - if the result overflows an int
    • minus

      public Days minus(Days days)
      Returns a new instance with the specified number of days taken away.

      This instance is immutable and unaffected by this method call.

      Parameters:
      days - the amount of days to take away, may be negative, null means zero
      Returns:
      the new period minus the specified number of days
      Throws:
      ArithmeticException - if the result overflows an int
    • multipliedBy

      public Days multipliedBy(int scalar)
      Returns a new instance with the days multiplied by the specified scalar.

      This instance is immutable and unaffected by this method call.

      Parameters:
      scalar - the amount to multiply by, may be negative
      Returns:
      the new period multiplied by the specified scalar
      Throws:
      ArithmeticException - if the result overflows an int
    • dividedBy

      public Days dividedBy(int divisor)
      Returns a new instance with the days divided by the specified divisor. The calculation uses integer division, thus 3 divided by 2 is 1.

      This instance is immutable and unaffected by this method call.

      Parameters:
      divisor - the amount to divide by, may be negative
      Returns:
      the new period divided by the specified divisor
      Throws:
      ArithmeticException - if the divisor is zero
    • negated

      public Days negated()
      Returns a new instance with the days value negated.
      Returns:
      the new period with a negated value
      Throws:
      ArithmeticException - if the result overflows an int
    • isGreaterThan

      public boolean isGreaterThan(Days other)
      Is this days instance greater than the specified number of days.
      Parameters:
      other - the other period, null means zero
      Returns:
      true if this days instance is greater than the specified one
    • isLessThan

      public boolean isLessThan(Days other)
      Is this days instance less than the specified number of days.
      Parameters:
      other - the other period, null means zero
      Returns:
      true if this days instance is less than the specified one
    • toString

      public String toString()
      Gets this instance as a String in the ISO8601 duration format.

      For example, "P4D" represents 4 days.

      Specified by:
      toString in interface ReadablePeriod
      Overrides:
      toString in class Object
      Returns:
      the value as an ISO8601 string