public Interface DateTimePropertyValidators

       Format Definition:  This property is defined by the following
      notation:

       completed  = "COMPLETED" compparam ":" date-time CRLF

       compparam  = *(";" other-param)

       Format Definition:  This property is defined by the following
      notation:

       dtend      = "DTEND" dtendparam ":" dtendval CRLF

       dtendparam = *(
                  ;
                  ; The following are OPTIONAL,
                  ; but MUST NOT occur more than once.
                  ;
                  (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
                  (";" tzidparam) /
                  ;
                  ; The following is OPTIONAL,
                  ; and MAY occur more than once.
                  ;
                  (";" other-param)
                  ;
                  )

       dtendval   = date-time / date
       ;Value MUST match value type

       Format Definition:  This property is defined by the following
      notation:

       dtstart    = "DTSTART" dtstparam ":" dtstval CRLF

       dtstparam  = *(
                  ;
                  ; The following are OPTIONAL,
                  ; but MUST NOT occur more than once.
                  ;
                  (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
                  (";" tzidparam) /
                  ;
                  ; The following is OPTIONAL,
                  ; and MAY occur more than once.
                  ;
                  (";" other-param)
                  ;
                  )

       dtstval    = date-time / date
       ;Value MUST match value type

      Format Definition:  This property is defined by the following
      notation:

       due        = "DUE" dueparam ":" dueval CRLF

       dueparam   = *(
                  ;
                  ; The following are OPTIONAL,
                  ; but MUST NOT occur more than once.
                  ;
                  (";" "VALUE" "=" ("DATE-TIME" / "DATE")) /
                  (";" tzidparam) /
                  ;
                  ; The following is OPTIONAL,
                  ; and MAY occur more than once.
                  ;
                  (";" other-param)
                  ;
                  )

       dueval     = date-time / date
       ;Value MUST match value type

       Format Definition:  This property is defined by the following
      notation:

       duration   = "DURATION" durparam ":" dur-value CRLF
                    ;consisting of a positive duration of time.

       durparam   = *(";" other-param)

       Format Definition:  This property is defined by the following
      notation:

       freebusy   = "FREEBUSY" fbparam ":" fbvalue CRLF

       fbparam    = *(
                  ;
                  ; The following is OPTIONAL,
                  ; but MUST NOT occur more than once.
                  ;
                  (";" fbtypeparam) /
                  ;
                  ; The following is OPTIONAL,
                  ; and MAY occur more than once.
                  ;
                  (";" other-param)
                  ;
                  )

       fbvalue    = period *("," period)
       ;Time value MUST be in the UTC time format.

      Format Definition:  This property is defined by the following
      notation:

       transp     = "TRANSP" transparam ":" transvalue CRLF

       transparam = *(";" other-param)

       transvalue = "OPAQUE"
                   ;Blocks or opaque on busy time searches.
                   / "TRANSPARENT"
                   ;Transparent on busy time searches.
       ;Default value is OPAQUE