Struts Interview Questions 2

6: What is ActionForm?
A: An ActionForm is a JavaBean that extends
org.apache.struts.action.ActionForm. ActionForm maintains the session state for
web application and the ActionForm object is automatically populated on the
server side with data entered from a form on the client side.

7: What is Struts Validator Framework?
A: Struts Framework provides the functionality to validate the form data.
It can be use to validate the data on the users browser as well as on the
server side. Struts Framework emits the java scripts and it can be used
validate the form data on the client browser. Server side validation of form
can be accomplished by sub classing your From Bean with DynaValidatorForm
class.
The Validator framework was developed by David Winterfeldt as third-party
add-on to Struts. Now the Validator framework is a part of Jakarta Commons
project and it can be used with or without Struts. The Validator framework
comes integrated with the Struts Framework and can be used without doing any
extra settings.

8: Give the Details of XML files used in Validator Framework?
A: The Validator Framework uses two XML configuration files
validator-rules.xml and validation.xml. The validator-rules.xml defines the
standard validation routines, these are reusable and used in validation.xml. to
define the form specific validations. The validation.xml defines the
validations applied to a form bean.

9: How you will display validation fail errors on jsp page?
A: Following tag displays all the errors:
<html:errors/>

10: How you will enable front-end validation based on the xml in
validation.xml?
A: The <html:javascript> tag to allow front-end validation based on
the xml in validation.xml. For example the code: <html:javascript
formName=\"logonForm\" dynamicJavascript=\"true\" staticJavascript=\"true\"
/> generates the client side java script for the form \"logonForm\" as
defined in the validation.xml file. The <html:javascript> when added in
the jsp file generates the client site validation script.