Annotation Interface DateTimeFormat


Declares that a field or method parameter should be formatted as a date or time.

Formatting applies to parsing a date/time object from a string as well as printing a date/time object to a string.

Supports formatting by style pattern, ISO date time pattern, or custom format pattern string. Can be applied to Date, Calendar, Long (for millisecond timestamps) as well as JSR-310 java.time value types.

For style-based formatting, set the style() attribute to the desired style pattern code. The first character of the code is the date style, and the second character is the time style. Specify a character of 'S' for short style, 'M' for medium, 'L' for long, and 'F' for full. The date or time may be omitted by specifying the style character '-' — for example, 'M-' specifies a medium format for the date with no time. The supported style pattern codes correlate to the enum constants defined in FormatStyle.

For ISO-based formatting, set the iso() attribute to the desired DateTimeFormat.ISO format, such as DateTimeFormat.ISO.DATE.

For custom formatting, set the pattern() attribute to a date time pattern, such as "yyyy/MM/dd hh:mm:ss a".

Each attribute is mutually exclusive, so only set one attribute per annotation instance (the one most convenient for your formatting needs).

  • When the pattern attribute is specified, it takes precedence over both the style and ISO attribute.
  • When the iso() attribute is specified, it takes precedence over the style attribute.
  • When no annotation attributes are specified, the default format applied is style-based with a style code of 'SS' (short date, short time).

Time Zones

Whenever the style() or pattern() attribute is used, the default time zone of the JVM will be used when formatting Date values. Whenever the iso() attribute is used when formatting Date values, UTC will be used as the time zone. The same time zone will be applied to any fallback patterns as well. In order to enforce consistent use of UTC as the time zone, you can bootstrap the JVM with -Duser.timezone=UTC.

Since:
3.0
Author:
Keith Donald, Juergen Hoeller, Sam Brannen
See Also:
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static enum 
    Common ISO date time format patterns.
  • Optional Element Summary

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    The set of custom patterns to use as a fallback in case parsing fails for the primary pattern(), iso(), or style() attribute.
    The ISO pattern to use to format the field or method parameter.
    The custom pattern to use to format the field or method parameter.
    The style pattern to use to format the field or method parameter.
  • Element Details

    • style

      String style
      The style pattern to use to format the field or method parameter.

      Defaults to 'SS' for short date, short time. Set this attribute when you wish to format your field or method parameter in accordance with a common style other than the default style.

      See the class-level documentation for further details.

      See Also:
      Default:
      "SS"
    • iso

      The ISO pattern to use to format the field or method parameter.

      Supported ISO patterns are defined in the DateTimeFormat.ISO enum.

      Defaults to DateTimeFormat.ISO.NONE, indicating this attribute should be ignored. Set this attribute when you wish to format your field or method parameter in accordance with an ISO format.

      See Also:
      Default:
      NONE
    • pattern

      String pattern
      The custom pattern to use to format the field or method parameter.

      Defaults to empty String, indicating no custom pattern String has been specified. Set this attribute when you wish to format your field or method parameter in accordance with a custom date time pattern not represented by a style or ISO format.

      Note: This pattern follows the original SimpleDateFormat style, as also supported by Joda-Time, with strict parsing semantics towards overflows (for example, rejecting a Feb 29 value for a non-leap-year). As a consequence, 'yy' characters indicate a year in the traditional style, not a "year-of-era" as in the DateTimeFormatter specification (i.e. 'yy' turns into 'uu' when going through a DateTimeFormatter with strict resolution mode).

      See Also:
      Default:
      ""
    • fallbackPatterns

      String[] fallbackPatterns
      The set of custom patterns to use as a fallback in case parsing fails for the primary pattern(), iso(), or style() attribute.

      For example, if you wish to use the ISO date format for parsing and printing but allow for lenient parsing of user input for various date formats, you could configure something similar to the following.

       @DateTimeFormat(iso = ISO.DATE, fallbackPatterns = { "M/d/yy", "dd.MM.yyyy" })
       

      Fallback patterns are only used for parsing. They are not used for printing the value as a String. The primary pattern(), iso(), or style() attribute is always used for printing. For details on which time zone is used for fallback patterns, see the class-level documentation.

      Fallback patterns are not supported for Joda-Time value types.

      Since:
      5.3.5
      Default:
      {}