Struts 2 validation Introduction
Struts2 Validation Framework
As the security and efficiency point of view validation of form’s input is necessary for every web application, to ensure that users enter valid information. The Apache Struts2 framework provides built-in robust validation support framework which is highly decoupled from the view and controller, thus it can be easily integrated to existing applications. In this section, we’ll learn how Struts2 validation works by creating a sample application that validates user’s input for a simple login form. Validation framework comes with set of useful routines to handle form validation automatically and it can handle both server side as well as client side form validation.
By default, the validation framework is included in Struts2 default stack and is “turned on” already so we don’t have to do anything to use it, except creating validation rules in an XML file in a correct manner and putting it into right place. We specify validation rules per action class in an XML file that follows either of these naming conventions: