Java To JSP passing

Hai friends,
               I finished one project. In that i have the date field as a third field. date field has the default value java script was working... Ihave problem in serverside revalidation. (ie) consider i enter first 2 fields and click submit button. it will revalidate data and through the error in fourth field like should not enter a blank data. my problem is i need that default value in the  3rd date field while i click that save button without enter a full data.