FieldPosition is a simple class used by Format
and its subclasses to identify fields in formatted output. Fields can
be identified in two ways:
By an integer constant, whose names typically end with
_FIELD. The constants are defined in the various
subclasses of Format.
By a Format.Field constant, see ERA_FIELD
and its friends in DateFormat for an example.
FieldPosition keeps track of the position of the
field within the formatted output with two indices: the index
of the first character of the field and the index of the last
character of the field.
One version of the format method in the various
Format classes requires a FieldPosition
object as an argument. You use this format method
to perform partial formatting or to get information about the
formatted output (such as the position of a field).
If you are interested in the positions of all attributes in the
formatted string use the Format method
formatToCharacterIterator.
FieldPositionis a simple class used byFormatand its subclasses to identify fields in formatted output. Fields can be identified in two ways:_FIELD. The constants are defined in the various subclasses ofFormat.Format.Fieldconstant, seeERA_FIELDand its friends inDateFormatfor an example.FieldPositionkeeps track of the position of the field within the formatted output with two indices: the index of the first character of the field and the index of the last character of the field.One version of the
formatmethod in the variousFormatclasses requires aFieldPositionobject as an argument. You use thisformatmethod to perform partial formatting or to get information about the formatted output (such as the position of a field).If you are interested in the positions of all attributes in the formatted string use the
FormatmethodformatToCharacterIterator.