Package org.joda.time

Class DateTime

java.lang.Object
org.joda.time.base.AbstractInstant
org.joda.time.base.AbstractDateTime
org.joda.time.base.BaseDateTime
org.joda.time.DateTime
All Implemented Interfaces:
Serializable, Comparable<ReadableInstant>, ReadableDateTime, ReadableInstant
public final class DateTime extends BaseDateTime implements ReadableDateTime, Serializable
DateTime is the standard implementation of an unmodifiable datetime class.

DateTime is the most widely used implementation of ReadableInstant. As with all instants, it represents an exact point on the time-line, but limited to the precision of milliseconds. A DateTime calculates its fields with respect to a time zone.

Internally, the class holds two pieces of data. Firstly, it holds the datetime as milliseconds from the Java epoch of 1970-01-01T00:00:00Z. Secondly, it holds a Chronology which determines how the millisecond instant value is converted into the date time fields. The default Chronology is ISOChronology which is the agreed international standard and compatible with the modern Gregorian calendar.

Each individual field can be queried in two ways:

  • getHourOfDay()
  • hourOfDay().get()
The second technique also provides access to other useful methods on the field:
  • numeric value
  • text value
  • short text value
  • maximum/minimum values
  • add/subtract
  • set
  • rounding

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

Since:
1.0
See Also:

  • Constructor Details

    • DateTime

      public DateTime()
      Constructs an instance set to the current system millisecond time using ISOChronology in the default time zone.
      See Also:

    • DateTime

      public DateTime(DateTimeZone zone)
      Constructs an instance set to the current system millisecond time using ISOChronology in the specified time zone.

      If the specified time zone is null, the default zone is used.

      Parameters:
      zone - the time zone, null means default zone
      See Also:

    • DateTime

      public DateTime(Chronology chronology)
      Constructs an instance set to the current system millisecond time using the specified chronology.

      If the chronology is null, ISOChronology in the default time zone is used.

      Parameters:
      chronology - the chronology, null means ISOChronology in default zone
      See Also:

    • DateTime

      public DateTime(long instant)
      Constructs an instance set to the milliseconds from 1970-01-01T00:00:00Z using ISOChronology in the default time zone.
      Parameters:
      instant - the milliseconds from 1970-01-01T00:00:00Z

    • DateTime

      public DateTime(long instant, DateTimeZone zone)
      Constructs an instance set to the milliseconds from 1970-01-01T00:00:00Z using ISOChronology in the specified time zone.

      If the specified time zone is null, the default zone is used.

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

    • DateTime

      public DateTime(long instant, Chronology chronology)
      Constructs an instance set to the milliseconds from 1970-01-01T00:00:00Z using the specified chronology.

      If the chronology is null, ISOChronology in the default time zone is used.

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

    • DateTime

      public DateTime(Object instant)
      Constructs an instance from an Object that represents a datetime.

      If the object implies a chronology (such as GregorianCalendar does), then that chronology will be used. Otherwise, ISO default is used. Thus if a GregorianCalendar is passed in, the chronology used will be GJ, but if a Date is passed in the chronology will be ISO.

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

      Parameters:
      instant - the datetime object, null means now
      Throws:
      IllegalArgumentException - if the instant is invalid

    • DateTime

      public DateTime(Object instant, DateTimeZone zone)
      Constructs an instance from an Object that represents a datetime, forcing the time zone to that specified.

      If the object implies a chronology (such as GregorianCalendar does), then that chronology will be used, but with the time zone adjusted. Otherwise, ISO is used in the specified time zone. If the specified time zone is null, the default zone is used. Thus if a GregorianCalendar is passed in, the chronology used will be GJ, but if a Date is passed in the chronology will be ISO.

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

      Parameters:
      instant - the datetime object, null means now
      zone - the time zone, null means default time zone
      Throws:
      IllegalArgumentException - if the instant is invalid

    • DateTime

      public DateTime(Object instant, Chronology chronology)
      Constructs an instance from an Object that represents a datetime, using the specified chronology.

      If the chronology is null, ISO in the default time zone is used. Any chronology implied by the object (such as GregorianCalendar does) is ignored.

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

      Parameters:
      instant - the datetime object, null means now
      chronology - the chronology, null means ISO in default zone
      Throws:
      IllegalArgumentException - if the instant is invalid

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour)
      Constructs an instance from datetime field values using ISOChronology in the default time zone.
      Parameters:
      year - the year
      monthOfYear - the month of the year, from 1 to 12
      dayOfMonth - the day of the month, from 1 to 31
      hourOfDay - the hour of the day, from 0 to 23
      minuteOfHour - the minute of the hour, from 0 to 59
      Since:
      2.0

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, DateTimeZone zone)
      Constructs an instance from datetime field values using ISOChronology in the specified time zone.

      If the specified time zone is null, the default zone is used.

      Parameters:
      year - the year
      monthOfYear - the month of the year, from 1 to 12
      dayOfMonth - the day of the month, from 1 to 31
      hourOfDay - the hour of the day, from 0 to 23
      minuteOfHour - the minute of the hour, from 0 to 59
      zone - the time zone, null means default time zone
      Since:
      2.0

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, Chronology chronology)
      Constructs an instance from datetime field values using the specified chronology.

      If the chronology is null, ISOChronology in the default time zone is used.

      Parameters:
      year - the year, valid values defined by the chronology
      monthOfYear - the month of the year, valid values defined by the chronology
      dayOfMonth - the day of the month, valid values defined by the chronology
      hourOfDay - the hour of the day, valid values defined by the chronology
      minuteOfHour - the minute of the hour, valid values defined by the chronology
      chronology - the chronology, null means ISOChronology in default zone
      Since:
      2.0

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, int secondOfMinute)
      Constructs an instance from datetime field values using ISOChronology in the default time zone.
      Parameters:
      year - the year
      monthOfYear - the month of the year, from 1 to 12
      dayOfMonth - the day of the month, from 1 to 31
      hourOfDay - the hour of the day, from 0 to 23
      minuteOfHour - the minute of the hour, from 0 to 59
      secondOfMinute - the second of the minute, from 0 to 59
      Since:
      2.0

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, int secondOfMinute, DateTimeZone zone)
      Constructs an instance from datetime field values using ISOChronology in the specified time zone.

      If the specified time zone is null, the default zone is used.

      Parameters:
      year - the year
      monthOfYear - the month of the year, from 1 to 12
      dayOfMonth - the day of the month, from 1 to 31
      hourOfDay - the hour of the day, from 0 to 23
      minuteOfHour - the minute of the hour, from 0 to 59
      secondOfMinute - the second of the minute, from 0 to 59
      zone - the time zone, null means default time zone
      Since:
      2.0

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, int secondOfMinute, Chronology chronology)
      Constructs an instance from datetime field values using the specified chronology.

      If the chronology is null, ISOChronology in the default time zone is used.

      Parameters:
      year - the year, valid values defined by the chronology
      monthOfYear - the month of the year, valid values defined by the chronology
      dayOfMonth - the day of the month, valid values defined by the chronology
      hourOfDay - the hour of the day, valid values defined by the chronology
      minuteOfHour - the minute of the hour, valid values defined by the chronology
      secondOfMinute - the second of the minute, valid values defined by the chronology
      chronology - the chronology, null means ISOChronology in default zone
      Since:
      2.0

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, int secondOfMinute, int millisOfSecond)
      Constructs an instance from datetime field values using ISOChronology in the default time zone.
      Parameters:
      year - the year
      monthOfYear - the month of the year, from 1 to 12
      dayOfMonth - the day of the month, from 1 to 31
      hourOfDay - the hour of the day, from 0 to 23
      minuteOfHour - the minute of the hour, from 0 to 59
      secondOfMinute - the second of the minute, from 0 to 59
      millisOfSecond - the millisecond of the second, from 0 to 999

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, int secondOfMinute, int millisOfSecond, DateTimeZone zone)
      Constructs an instance from datetime field values using ISOChronology in the specified time zone.

      If the specified time zone is null, the default zone is used.

      Parameters:
      year - the year
      monthOfYear - the month of the year, from 1 to 12
      dayOfMonth - the day of the month, from 1 to 31
      hourOfDay - the hour of the day, from 0 to 23
      minuteOfHour - the minute of the hour, from 0 to 59
      secondOfMinute - the second of the minute, from 0 to 59
      millisOfSecond - the millisecond of the second, from 0 to 999
      zone - the time zone, null means default time zone

    • DateTime

      public DateTime(int year, int monthOfYear, int dayOfMonth, int hourOfDay, int minuteOfHour, int secondOfMinute, int millisOfSecond, Chronology chronology)
      Constructs an instance from datetime field values using the specified chronology.

      If the chronology is null, ISOChronology in the default time zone is used.

      Parameters:
      year - the year, valid values defined by the chronology
      monthOfYear - the month of the year, valid values defined by the chronology
      dayOfMonth - the day of the month, valid values defined by the chronology
      hourOfDay - the hour of the day, valid values defined by the chronology
      minuteOfHour - the minute of the hour, valid values defined by the chronology
      secondOfMinute - the second of the minute, valid values defined by the chronology
      millisOfSecond - the millisecond of the second, valid values defined by the chronology
      chronology - the chronology, null means ISOChronology in default zone

  • Method Details

    • now

      public static DateTime now()
      Obtains a DateTime set to the current system millisecond time using ISOChronology in the default time zone.
      Returns:
      the current date-time, not null
      Since:
      2.0

    • now

      public static DateTime now(DateTimeZone zone)
      Obtains a DateTime set to the current system millisecond time using ISOChronology in the specified time zone.
      Parameters:
      zone - the time zone, not null
      Returns:
      the current date-time, not null
      Since:
      2.0

    • now

      public static DateTime now(Chronology chronology)
      Obtains a DateTime set to the current system millisecond time using the specified chronology.
      Parameters:
      chronology - the chronology, not null
      Returns:
      the current date-time, not null
      Since:
      2.0

    • parse

      public static DateTime parse(String str)
      Parses a DateTime from the specified string.

      This uses ISODateTimeFormat.dateTimeParser().withOffsetParsed() which is different to passing a String to the constructor.

      Sometimes this method and new DateTime(str) return different results. This can be confusing as the difference is not visible in AbstractDateTime.toString().

      When passed a date-time string without an offset, such as '2010-06-30T01:20', both the constructor and this method use the default time-zone. As such, DateTime.parse("2010-06-30T01:20") and new DateTime("2010-06-30T01:20")) are equal.

      However, when this method is passed a date-time string with an offset, the offset is directly parsed and stored. As such, DateTime.parse("2010-06-30T01:20+02:00") and new DateTime("2010-06-30T01:20+02:00")) are NOT equal. The object produced via this method has a zone of DateTimeZone.forOffsetHours(2). The object produced via the constructor has a zone of DateTimeZone.getDefault().

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

    • parse

      public static DateTime parse(String str, DateTimeFormatter formatter)
      Parses a DateTime 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

    • toDateTime

      public DateTime toDateTime()
      Get this object as a DateTime by returning this.
      Specified by:
      toDateTime in interface ReadableDateTime
      Overrides:
      toDateTime in class AbstractInstant
      Returns:
      this

    • toDateTimeISO

      public DateTime toDateTimeISO()
      Get this object as a DateTime using ISOChronology in the default zone, returning this if possible.
      Overrides:
      toDateTimeISO in class AbstractInstant
      Returns:
      a DateTime using the same millis

    • toDateTime

      public DateTime toDateTime(DateTimeZone zone)
      Get this object as a DateTime, returning this if possible.
      Overrides:
      toDateTime in class AbstractInstant
      Parameters:
      zone - time zone to apply, or default if null
      Returns:
      a DateTime using the same millis

    • toDateTime

      public DateTime toDateTime(Chronology chronology)
      Get this object as a DateTime, returning this if possible.
      Overrides:
      toDateTime in class AbstractInstant
      Parameters:
      chronology - chronology to apply, or ISOChronology if null
      Returns:
      a DateTime using the same millis

    • withMillis

      public DateTime withMillis(long newMillis)
      Returns a copy of this datetime with different millis.

      The returned object will be either be a new instance or this. Only the millis will change, the chronology and time zone are kept.

      Parameters:
      newMillis - the new millis, from 1970-01-01T00:00:00Z
      Returns:
      a copy of this datetime with different millis

    • withChronology

      public DateTime withChronology(Chronology newChronology)
      Returns a copy of this datetime with a different chronology.

      The returned object will be either be a new instance or this. Only the chronology will change, the millis are kept.

      Parameters:
      newChronology - the new chronology, null means ISO default
      Returns:
      a copy of this datetime with a different chronology

    • withZone

      public DateTime withZone(DateTimeZone newZone)
      Returns a copy of this datetime with a different time zone, preserving the millisecond instant.

      This method is useful for finding the local time in another timezone. For example, if this instant holds 12:30 in Europe/London, the result from this method with Europe/Paris would be 13:30.

      The returned object will be a new instance of the same implementation type. This method changes the time zone, and does not change the millisecond instant, with the effect that the field values usually change. The returned object will be either be a new instance or this.

      Parameters:
      newZone - the new time zone
      Returns:
      a copy of this datetime with a different time zone
      See Also:

    • withZoneRetainFields

      public DateTime withZoneRetainFields(DateTimeZone newZone)
      Returns a copy of this datetime with a different time zone, preserving the field values.

      This method is useful for finding the millisecond time in another timezone. For example, if this instant holds 12:30 in Europe/London (ie. 12:30Z), the result from this method with Europe/Paris would be 12:30 (ie. 11:30Z).

      The returned object will be a new instance of the same implementation type. This method changes the time zone and the millisecond instant to keep the field values the same. The returned object will be either be a new instance or this.

      Parameters:
      newZone - the new time zone, null means default
      Returns:
      a copy of this datetime with a different time zone
      See Also:

    • withEarlierOffsetAtOverlap

      public DateTime withEarlierOffsetAtOverlap()
      Returns a copy of this ZonedDateTime changing the zone offset to the earlier of the two valid offsets at a local time-line overlap.

      This method only has any effect when the local time-line overlaps, such as at an autumn daylight savings cutover. In this scenario, there are two valid offsets for the local date-time. Calling this method will return a date-time with the earlier of the two selected.

      If this method is called when it is not an overlap, this is returned.

      This instance is immutable and unaffected by this method call.

      Returns:
      a copy of this datetime with the earliest valid offset for the local datetime

    • withLaterOffsetAtOverlap

      public DateTime withLaterOffsetAtOverlap()
      Returns a copy of this ZonedDateTime changing the zone offset to the later of the two valid offsets at a local time-line overlap.

      This method only has any effect when the local time-line overlaps, such as at an autumn daylight savings cutover. In this scenario, there are two valid offsets for the local date-time. Calling this method will return a date-time with the later of the two selected.

      If this method is called when it is not an overlap, this is returned.

      This instance is immutable and unaffected by this method call.

      Returns:
      a copy of this datetime with the latest valid offset for the local datetime

    • withDate

      public DateTime withDate(int year, int monthOfYear, int dayOfMonth)
      Returns a copy of this datetime with the specified date, retaining the time fields.

      If the date is already the date passed in, then this is returned.

      To set a single field use the properties, for example: 

       DateTime set = monthOfYear().setCopy(6);

      If the time is invalid on the new date due to the time-zone, the time will be adjusted.

      This instance is immutable and unaffected by this method call.

      Parameters:
      year - the new year value
      monthOfYear - the new monthOfYear value
      dayOfMonth - the new dayOfMonth value
      Returns:
      a copy of this datetime with a different date
      Throws:
      IllegalArgumentException - if any value if invalid

    • withDate

      public DateTime withDate(LocalDate date)
      Returns a copy of this datetime with the specified date, retaining the time fields.

      If the time is invalid on the new date due to the time-zone, the time will be adjusted.

      This instance is immutable and unaffected by this method call.

      Parameters:
      date - the local date
      Returns:
      a copy of this datetime with a different date
      Throws:
      IllegalArgumentException - if the time-of-day is invalid for the date
      NullPointerException - if the date is null

    • withTime

      public DateTime withTime(int hourOfDay, int minuteOfHour, int secondOfMinute, int millisOfSecond)
      Returns a copy of this datetime with the specified time, retaining the date fields.

      If the time is already the time passed in, then this is returned.

      To set a single field use the properties, for example: 

       DateTime set = dt.hourOfDay().setCopy(6);

      If the new time is invalid due to the time-zone, the time will be adjusted.

      This instance is immutable and unaffected by this method call.

      Parameters:
      hourOfDay - the hour of the day
      minuteOfHour - the minute of the hour
      secondOfMinute - the second of the minute
      millisOfSecond - the millisecond of the second
      Returns:
      a copy of this datetime with a different time
      Throws:
      IllegalArgumentException - if any value if invalid

    • withTime

      public DateTime withTime(LocalTime time)
      Returns a copy of this datetime with the specified time, retaining the date fields.

      If the new time is invalid due to the time-zone, the time will be adjusted.

      This instance is immutable and unaffected by this method call.

      Parameters:
      time - the local time
      Returns:
      a copy of this datetime with a different time
      Throws:
      IllegalArgumentException - if the time-of-day is invalid for the date
      NullPointerException - if the time is null

    • withTimeAtStartOfDay

      public DateTime withTimeAtStartOfDay()
      Returns a copy of this datetime with the time set to the start of the day.

      The time will normally be midnight, as that is the earliest time on any given day. However, in some time zones when Daylight Savings Time starts, there is no midnight because time jumps from 11:59 to 01:00. This method handles that situation by returning 01:00 on that date.

      This instance is immutable and unaffected by this method call.

      Returns:
      a copy of this datetime with the time set to the start of the day, not null

    • withFields

      public DateTime withFields(ReadablePartial partial)
      Returns a copy of this datetime with the partial set of fields replacing those from this instance.

      For example, if the partial is a TimeOfDay then the time fields would be changed in the returned instance. If the partial is null, then this is returned.

      Parameters:
      partial - the partial set of fields to apply to this datetime, null ignored
      Returns:
      a copy of this datetime with a different set of fields
      Throws:
      IllegalArgumentException - if any value is invalid

    • withField

      public DateTime withField(DateTimeFieldType fieldType, int value)
      Returns a copy of this datetime with the specified field set to a new value.

      For example, if the field type is hourOfDay then the hour of day field would be changed in the returned instance. If the field type is null, then this is returned.

      These three lines are equivalent: 

       DateTime updated = dt.withField(DateTimeFieldType.dayOfMonth(), 6);
 DateTime updated = dt.dayOfMonth().setCopy(6);
 DateTime updated = dt.property(DateTimeFieldType.dayOfMonth()).setCopy(6);
      Parameters:
      fieldType - the field type to set, not null
      value - the value to set
      Returns:
      a copy of this datetime with the field set
      Throws:
      IllegalArgumentException - if the value is null or invalid

    • withFieldAdded

      public DateTime withFieldAdded(DurationFieldType fieldType, int amount)
      Returns a copy of this datetime with the value of the specified field increased.

      If the addition is zero or the field is null, then this is returned.

      These three lines are equivalent: 

       DateTime added = dt.withFieldAdded(DurationFieldType.years(), 6);
 DateTime added = dt.plusYears(6);
 DateTime added = dt.plus(Period.years(6));
      Parameters:
      fieldType - the field type to add to, not null
      amount - the amount to add
      Returns:
      a copy of this datetime with the field updated
      Throws:
      IllegalArgumentException - if the value is null or invalid
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • withDurationAdded

      public DateTime withDurationAdded(long durationToAdd, int scalar)
      Returns a copy of this datetime with the specified duration added.

      If the addition is zero, then this is returned.

      Parameters:
      durationToAdd - the duration to add to this one
      scalar - the amount of times to add, such as -1 to subtract once
      Returns:
      a copy of this datetime with the duration added
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • withDurationAdded

      public DateTime withDurationAdded(ReadableDuration durationToAdd, int scalar)
      Returns a copy of this datetime with the specified duration added.

      If the addition is zero, then this is returned.

      Parameters:
      durationToAdd - the duration 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 datetime with the duration added
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • withPeriodAdded

      public DateTime withPeriodAdded(ReadablePeriod period, int scalar)
      Returns a copy of this datetime with the specified period added.

      If the addition is zero, then this is returned.

      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 plusYears(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 datetime with the period added
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • plus

      public DateTime plus(long duration)
      Returns a copy of this datetime with the specified duration added.

      If the amount is zero or null, then this is returned. This datetime instance is immutable and unaffected by this method call.

      Parameters:
      duration - the duration, in millis, to add to this one
      Returns:
      a copy of this datetime with the duration added
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • plus

      public DateTime plus(ReadableDuration duration)
      Returns a copy of this datetime with the specified duration added.

      If the amount is zero or null, then this is returned. This datetime instance is immutable and unaffected by this method call.

      Parameters:
      duration - the duration to add to this one, null means zero
      Returns:
      a copy of this datetime with the duration added
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • plus

      public DateTime plus(ReadablePeriod period)
      Returns a copy of this datetime with the specified period added.

      This method will add each element of the period one by one, from largest to smallest, adjusting the datetime to be accurate between each.

      Thus, adding a period of one month and one day to 2007-03-31 will work as follows: First add one month and adjust, resulting in 2007-04-30 Then add one day and adjust, resulting in 2007-05-01.

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

      If the amount is zero or null, then this is returned. This datetime instance is immutable and unaffected by this method call.

      Parameters:
      period - the duration to add to this one, null means zero
      Returns:
      a copy of this datetime with the period added
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • plusYears

      public DateTime plusYears(int years)
      Returns a copy of this datetime plus the specified number of years.

      The calculation will do its best to only change the year field retaining the same month of year. However, in certain circumstances, it may be necessary to alter smaller fields. For example, 2008-02-29 plus one year cannot result in 2009-02-29, so the day of month is adjusted to 2009-02-28.

      The following three lines are identical in effect: 

       DateTime added = dt.plusYears(6);
 DateTime added = dt.plus(Period.years(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.years(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      years - the amount of years to add, may be negative
      Returns:
      the new datetime plus the increased years
      Since:
      1.1

    • plusMonths

      public DateTime plusMonths(int months)
      Returns a copy of this datetime plus the specified number of months.

      The calculation will do its best to only change the month field retaining the same day of month. However, in certain circumstances, it may be necessary to alter smaller fields. For example, 2007-03-31 plus one month cannot result in 2007-04-31, so the day of month is adjusted to 2007-04-30.

      The following three lines are identical in effect: 

       DateTime added = dt.plusMonths(6);
 DateTime added = dt.plus(Period.months(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.months(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      months - the amount of months to add, may be negative
      Returns:
      the new datetime plus the increased months
      Since:
      1.1

    • plusWeeks

      public DateTime plusWeeks(int weeks)
      Returns a copy of this datetime plus the specified number of weeks.

      The calculation operates as if it were adding the equivalent in days.

      The following three lines are identical in effect: 

       DateTime added = dt.plusWeeks(6);
 DateTime added = dt.plus(Period.weeks(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.weeks(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      weeks - the amount of weeks to add, may be negative
      Returns:
      the new datetime plus the increased weeks
      Since:
      1.1

    • plusDays

      public DateTime plusDays(int days)
      Returns a copy of this datetime plus the specified number of days.

      The calculation will do its best to only change the day field retaining the same time of day. However, in certain circumstances, typically daylight savings cutover, it may be necessary to alter the time fields.

      In spring an hour is typically removed. If adding one day results in the time being within the cutover then the time is adjusted to be within summer time. For example, if the cutover is from 01:59 to 03:00 and the result of this method would have been 02:30, then the result will be adjusted to 03:30.

      The following three lines are identical in effect: 

       DateTime added = dt.plusDays(6);
 DateTime added = dt.plus(Period.days(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.days(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      days - the amount of days to add, may be negative
      Returns:
      the new datetime plus the increased days
      Since:
      1.1

    • plusHours

      public DateTime plusHours(int hours)
      Returns a copy of this datetime plus the specified number of hours.

      The calculation will add a duration equivalent to the number of hours expressed in milliseconds.

      For example, if a spring daylight savings cutover is from 01:59 to 03:00 then adding one hour to 01:30 will result in 03:30. This is a duration of one hour later, even though the hour field value changed from 1 to 3.

      The following three lines are identical in effect: 

       DateTime added = dt.plusHours(6);
 DateTime added = dt.plus(Period.hours(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.hours(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      hours - the amount of hours to add, may be negative
      Returns:
      the new datetime plus the increased hours
      Since:
      1.1

    • plusMinutes

      public DateTime plusMinutes(int minutes)
      Returns a copy of this datetime plus the specified number of minutes.

      The calculation will add a duration equivalent to the number of minutes expressed in milliseconds.

      The following three lines are identical in effect: 

       DateTime added = dt.plusMinutes(6);
 DateTime added = dt.plus(Period.minutes(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.minutes(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      minutes - the amount of minutes to add, may be negative
      Returns:
      the new datetime plus the increased minutes
      Since:
      1.1

    • plusSeconds

      public DateTime plusSeconds(int seconds)
      Returns a copy of this datetime plus the specified number of seconds.

      The calculation will add a duration equivalent to the number of seconds expressed in milliseconds.

      The following three lines are identical in effect: 

       DateTime added = dt.plusSeconds(6);
 DateTime added = dt.plus(Period.seconds(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.seconds(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      seconds - the amount of seconds to add, may be negative
      Returns:
      the new datetime plus the increased seconds
      Since:
      1.1

    • plusMillis

      public DateTime plusMillis(int millis)
      Returns a copy of this datetime plus the specified number of millis.

      The calculation will add a duration equivalent to the number of milliseconds.

      The following three lines are identical in effect: 

       DateTime added = dt.plusMillis(6);
 DateTime added = dt.plus(Period.millis(6));
 DateTime added = dt.withFieldAdded(DurationFieldType.millis(), 6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      millis - the amount of millis to add, may be negative
      Returns:
      the new datetime plus the increased millis
      Since:
      1.1

    • minus

      public DateTime minus(long duration)
      Returns a copy of this datetime with the specified duration taken away.

      If the amount is zero or null, then this is returned. This datetime instance is immutable and unaffected by this method call.

      Parameters:
      duration - the duration, in millis, to reduce this instant by
      Returns:
      a copy of this datetime with the duration taken away
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • minus

      public DateTime minus(ReadableDuration duration)
      Returns a copy of this datetime with the specified duration taken away.

      If the amount is zero or null, then this is returned. This datetime instance is immutable and unaffected by this method call.

      Parameters:
      duration - the duration to reduce this instant by
      Returns:
      a copy of this datetime with the duration taken away
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • minus

      public DateTime minus(ReadablePeriod period)
      Returns a copy of this datetime with the specified period taken away.

      This method will subtract each element of the period one by one, from largest to smallest, adjusting the datetime to be accurate between each.

      Thus, subtracting a period of one month and one day from 2007-05-31 will work as follows: First subtract one month and adjust, resulting in 2007-04-30 Then subtract one day and adjust, resulting in 2007-04-29. Note that the day has been adjusted by two.

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

      If the amount is zero or null, then this is returned. This datetime instance is immutable and unaffected by this method call.

      Parameters:
      period - the period to reduce this instant by
      Returns:
      a copy of this datetime with the period taken away
      Throws:
      ArithmeticException - if the new datetime exceeds the capacity of a long

    • minusYears

      public DateTime minusYears(int years)
      Returns a copy of this datetime minus the specified number of years.

      The calculation will do its best to only change the year field retaining the same month of year. However, in certain circumstances, it may be necessary to alter smaller fields. For example, 2008-02-29 minus one year cannot result in 2007-02-29, so the day of month is adjusted to 2007-02-28.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusYears(6);
 DateTime subtracted = dt.minus(Period.years(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.years(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      years - the amount of years to subtract, may be negative
      Returns:
      the new datetime minus the increased years
      Since:
      1.1

    • minusMonths

      public DateTime minusMonths(int months)
      Returns a copy of this datetime minus the specified number of months.

      The calculation will do its best to only change the month field retaining the same day of month. However, in certain circumstances, it may be necessary to alter smaller fields. For example, 2007-05-31 minus one month cannot result in 2007-04-31, so the day of month is adjusted to 2007-04-30.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusMonths(6);
 DateTime subtracted = dt.minus(Period.months(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.months(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      months - the amount of months to subtract, may be negative
      Returns:
      the new datetime minus the increased months
      Since:
      1.1

    • minusWeeks

      public DateTime minusWeeks(int weeks)
      Returns a copy of this datetime minus the specified number of weeks.

      The calculation operates as if it were subtracting the equivalent in days.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusWeeks(6);
 DateTime subtracted = dt.minus(Period.weeks(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.weeks(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      weeks - the amount of weeks to subtract, may be negative
      Returns:
      the new datetime minus the increased weeks
      Since:
      1.1

    • minusDays

      public DateTime minusDays(int days)
      Returns a copy of this datetime minus the specified number of days.

      The calculation will do its best to only change the day field retaining the same time of day. However, in certain circumstances, typically daylight savings cutover, it may be necessary to alter the time fields.

      In spring an hour is typically removed. If subtracting one day results in the time being within the cutover then the time is adjusted to be within summer time. For example, if the cutover is from 01:59 to 03:00 and the result of this method would have been 02:30, then the result will be adjusted to 03:30.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusDays(6);
 DateTime subtracted = dt.minus(Period.days(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.days(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      days - the amount of days to subtract, may be negative
      Returns:
      the new datetime minus the increased days
      Since:
      1.1

    • minusHours

      public DateTime minusHours(int hours)
      Returns a copy of this datetime minus the specified number of hours.

      The calculation will subtract a duration equivalent to the number of hours expressed in milliseconds.

      For example, if a spring daylight savings cutover is from 01:59 to 03:00 then subtracting one hour from 03:30 will result in 01:30. This is a duration of one hour earlier, even though the hour field value changed from 3 to 1.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusHours(6);
 DateTime subtracted = dt.minus(Period.hours(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.hours(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      hours - the amount of hours to subtract, may be negative
      Returns:
      the new datetime minus the increased hours
      Since:
      1.1

    • minusMinutes

      public DateTime minusMinutes(int minutes)
      Returns a copy of this datetime minus the specified number of minutes.

      The calculation will subtract a duration equivalent to the number of minutes expressed in milliseconds.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusMinutes(6);
 DateTime subtracted = dt.minus(Period.minutes(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.minutes(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      minutes - the amount of minutes to subtract, may be negative
      Returns:
      the new datetime minus the increased minutes
      Since:
      1.1

    • minusSeconds

      public DateTime minusSeconds(int seconds)
      Returns a copy of this datetime minus the specified number of seconds.

      The calculation will subtract a duration equivalent to the number of seconds expressed in milliseconds.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusSeconds(6);
 DateTime subtracted = dt.minus(Period.seconds(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.seconds(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      seconds - the amount of seconds to subtract, may be negative
      Returns:
      the new datetime minus the increased seconds
      Since:
      1.1

    • minusMillis

      public DateTime minusMillis(int millis)
      Returns a copy of this datetime minus the specified number of millis.

      The calculation will subtract a duration equivalent to the number of milliseconds.

      The following three lines are identical in effect: 

       DateTime subtracted = dt.minusMillis(6);
 DateTime subtracted = dt.minus(Period.millis(6));
 DateTime subtracted = dt.withFieldAdded(DurationFieldType.millis(), -6);

      This datetime instance is immutable and unaffected by this method call.

      Parameters:
      millis - the amount of millis to subtract, may be negative
      Returns:
      the new datetime minus the increased millis
      Since:
      1.1

    • property

      public DateTime.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 chronology for
      Returns:
      the property object
      Throws:
      IllegalArgumentException - if the field is null or unsupported

    • toDateMidnight

      @Deprecated public DateMidnight toDateMidnight()
      Deprecated.
      DateMidnight is deprecated
      Converts this object to a DateMidnight using the same millis and chronology.
      Returns:
      a DateMidnight using the same millis and chronology

    • toYearMonthDay

      @Deprecated public YearMonthDay toYearMonthDay()
      Deprecated.
      Use LocalDate instead of YearMonthDay
      Converts this object to a YearMonthDay using the same millis and chronology.
      Returns:
      a YearMonthDay using the same millis and chronology

    • toTimeOfDay

      @Deprecated public TimeOfDay toTimeOfDay()
      Deprecated.
      Use LocalTime instead of TimeOfDay
      Converts this object to a TimeOfDay using the same millis and chronology.
      Returns:
      a TimeOfDay using the same millis and chronology

    • toLocalDateTime

      public LocalDateTime toLocalDateTime()
      Converts this object to a LocalDateTime with the same datetime and chronology.
      Returns:
      a LocalDateTime with the same datetime and chronology
      Since:
      1.3

    • toLocalDate

      public LocalDate toLocalDate()
      Converts this object to a LocalDate with the same date and chronology.
      Returns:
      a LocalDate with the same date and chronology
      Since:
      1.3

    • toLocalTime

      public LocalTime toLocalTime()
      Converts this object to a LocalTime with the same time and chronology.
      Returns:
      a LocalTime with the same time and chronology
      Since:
      1.3

    • withEra

      public DateTime withEra(int era)
      Returns a copy of this datetime with the era field updated.

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

      Parameters:
      era - the era to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withCenturyOfEra

      public DateTime withCenturyOfEra(int centuryOfEra)
      Returns a copy of this datetime with the century of era field updated.

      DateTime is immutable, so there are no set methods. Instead, this method returns a new instance with the value of century of era changed.

      Parameters:
      centuryOfEra - the century of era to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withYearOfEra

      public DateTime withYearOfEra(int yearOfEra)
      Returns a copy of this datetime with the year of era field updated.

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

      Parameters:
      yearOfEra - the year of era to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withYearOfCentury

      public DateTime withYearOfCentury(int yearOfCentury)
      Returns a copy of this datetime with the year of century field updated.

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

      Parameters:
      yearOfCentury - the year of century to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withYear

      public DateTime withYear(int year)
      Returns a copy of this datetime with the year field updated.

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

      Parameters:
      year - the year to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withWeekyear

      public DateTime withWeekyear(int weekyear)
      Returns a copy of this datetime with the weekyear field updated.

      The weekyear is the year that matches with the weekOfWeekyear field. In the standard ISO8601 week algorithm, the first week of the year is that in which at least 4 days are in the year. As a result of this definition, day 1 of the first week may be in the previous year. The weekyear allows you to query the effective year for that day.

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

      Parameters:
      weekyear - the weekyear to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withMonthOfYear

      public DateTime withMonthOfYear(int monthOfYear)
      Returns a copy of this datetime with the month of year field updated.

      DateTime 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
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withWeekOfWeekyear

      public DateTime withWeekOfWeekyear(int weekOfWeekyear)
      Returns a copy of this datetime with the week of weekyear field updated.

      This field is associated with the "weekyear" via withWeekyear(int). In the standard ISO8601 week algorithm, the first week of the year is that in which at least 4 days are in the year. As a result of this definition, day 1 of the first week may be in the previous year.

      DateTime is immutable, so there are no set methods. Instead, this method returns a new instance with the value of week of weekyear changed.

      Parameters:
      weekOfWeekyear - the week of weekyear to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withDayOfYear

      public DateTime withDayOfYear(int dayOfYear)
      Returns a copy of this datetime with the day of year field updated.

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

      Parameters:
      dayOfYear - the day of year to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withDayOfMonth

      public DateTime withDayOfMonth(int dayOfMonth)
      Returns a copy of this datetime with the day of month field updated.

      DateTime 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
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withDayOfWeek

      public DateTime withDayOfWeek(int dayOfWeek)
      Returns a copy of this datetime with the day of week field updated.

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

      Parameters:
      dayOfWeek - the day of week to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withHourOfDay

      public DateTime withHourOfDay(int hour)
      Returns a copy of this datetime with the hour of day field updated.

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

      Parameters:
      hour - the hour of day to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withMinuteOfHour

      public DateTime withMinuteOfHour(int minute)
      Returns a copy of this datetime with the minute of hour updated.

      DateTime is immutable, so there are no set methods. Instead, this method returns a new instance with the value of minute of hour changed.

      Parameters:
      minute - the minute of hour to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withSecondOfMinute

      public DateTime withSecondOfMinute(int second)
      Returns a copy of this datetime with the second of minute field updated.

      DateTime is immutable, so there are no set methods. Instead, this method returns a new instance with the value of second of minute changed.

      Parameters:
      second - the second of minute to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withMillisOfSecond

      public DateTime withMillisOfSecond(int millis)
      Returns a copy of this datetime with the millis of second field updated.

      DateTime is immutable, so there are no set methods. Instead, this method returns a new instance with the value of millis of second changed.

      Parameters:
      millis - the millis of second to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • withMillisOfDay

      public DateTime withMillisOfDay(int millis)
      Returns a copy of this datetime with the millis of day field updated.

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

      Parameters:
      millis - the millis of day to set
      Returns:
      a copy of this object with the field set
      Throws:
      IllegalArgumentException - if the value is invalid
      Since:
      1.3

    • era

      public DateTime.Property era()
      Get the era property which provides access to advanced functionality.
      Returns:
      the era property

    • centuryOfEra

      public DateTime.Property centuryOfEra()
      Get the century of era property which provides access to advanced functionality.
      Returns:
      the year of era property

    • yearOfCentury

      public DateTime.Property yearOfCentury()
      Get the year of century property which provides access to advanced functionality.
      Returns:
      the year of era property

    • yearOfEra

      public DateTime.Property yearOfEra()
      Get the year of era property which provides access to advanced functionality.
      Returns:
      the year of era property

    • year

      public DateTime.Property year()
      Get the year property which provides access to advanced functionality.
      Returns:
      the year property

    • weekyear

      public DateTime.Property weekyear()
      Get the year of a week based year property which provides access to advanced functionality.
      Returns:
      the year of a week based year property

    • monthOfYear

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

    • weekOfWeekyear

      public DateTime.Property weekOfWeekyear()
      Get the week of a week based year property which provides access to advanced functionality.
      Returns:
      the week of a week based year property

    • dayOfYear

      public DateTime.Property dayOfYear()
      Get the day of year property which provides access to advanced functionality.
      Returns:
      the day of year property

    • dayOfMonth

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

    • dayOfWeek

      public DateTime.Property dayOfWeek()
      Get the day of week property which provides access to advanced functionality.
      Returns:
      the day of week property

    • hourOfDay

      public DateTime.Property hourOfDay()
      Get the hour of day field property which provides access to advanced functionality.
      Returns:
      the hour of day property

    • minuteOfDay

      public DateTime.Property minuteOfDay()
      Get the minute of day property which provides access to advanced functionality.
      Returns:
      the minute of day property

    • minuteOfHour

      public DateTime.Property minuteOfHour()
      Get the minute of hour field property which provides access to advanced functionality.
      Returns:
      the minute of hour property

    • secondOfDay

      public DateTime.Property secondOfDay()
      Get the second of day property which provides access to advanced functionality.
      Returns:
      the second of day property

    • secondOfMinute

      public DateTime.Property secondOfMinute()
      Get the second of minute field property which provides access to advanced functionality.
      Returns:
      the second of minute property

    • millisOfDay

      public DateTime.Property millisOfDay()
      Get the millis of day property which provides access to advanced functionality.
      Returns:
      the millis of day property

    • millisOfSecond

      public DateTime.Property millisOfSecond()
      Get the millis of second property which provides access to advanced functionality.
      Returns:
      the millis of second property