Servlets :: Front End JSP Conforming To SQL

A data entry form is on the front end. This allows one to enter say emails, addresses, etc. It utilizes a jsp, jstl, servlets, and beans. The backend sql has say a size of 50 for email. If more than 50 char are entered on the form, w/o any intervention, a truncation error is thrown. A static class was set up to hold the input element names and max sizes. It seems to work well keeping all in check, names and sizes on form, names in servlets, size of sql.

servlet
req.setAttribute(elementname, elementobject)
jsp
maxlength="${date.maxLength}"
name="${date.inputName}" //setattribute objects

servlet
.getInputElement("date").getInputName() //static map...shared with above objects

Is there any other system of keeping everything in sync. I am building it all, but I was wondering how this is parsed out if there are separate sql, middle-tier, and front-end developer? It seems better just to have good documentation that would be shared between the different implementers.