Since you are using Struts 2.3.x, you should update the doctype of your Struts.xml as well:
The typical problem I have with validation is matching the action name, action class and method in the validation file name.
I would take the following steps:
1. rename the action name in struts.xml to something other than the action class name (i.e. register).
2. change the validation file name to match the action class name and the action name (i.e. EmployeeAction-register-validation.xml)
3. place a debug statement in the action.execute method (if this is printed out, we know that validation didn't work. It rules out having a bad mapping for the input result in struts.xml)
4. reduce the validation to a single field and a single, simple validator (like "required"). This should rule out any other errors in the validation file.
Do that and check your server log files to see if there's any errors processing the files.
I have been able to resolve the issue.It was a problem regarding the location of the validation.xml file. It should go under src/main/resources/<my package>. Here goes the correct structure. However, Thanks a ton for spending your time.
Oh, are you using Maven to build? The "best practice" for Maven is to put non-source files to be in the "resources" directory. I always use Ant and the "best practice" for it is to have the source and validation files in the same directory, since that is where they will be in the WAR.