Returns a copy of this period with the specified amount of days.
!(p)
This sets the amount of the days unit _in a copy of this period.
The years and months units are unaffected.
!(p)
This instance is immutable and unaffected by this method call.
@param days the days to represent, may be negative
@return a {@code Period} based on this period with the requested days, not null
Returns a copy of this period with the specified amount of days. !(p) This sets the amount of the days unit _in a copy of this period. The years and months units are unaffected. !(p) This instance is immutable and unaffected by this method call.
@param days the days to represent, may be negative @return a {@code Period} based on this period with the requested days, not null