When using Struts, you can easily validate datas before excute. So many way to validate the form with Struts, you can use JavaScripts, XML validator…many, many way to validate them…This article is not a new way for this, but it’s simple to use if you’re not sure about use javascript or other way.
Before use validating, you must sure that you can create the Struts form. If not, read following article, it’s a tutorial how to Create Basic Struts Form.