I found something
about this in JGuru forums:



" In your JSP file containing



onsubmit="return validateFindAppForm(this);"



add this to the bottom just before you close your html body.







Adding the above will add in Client side (Java Script) Validation.

If you want to have Server Side Validation, try this.

In your FindAppAction
Class (Your Action Class) try putting in this method.

public ActionForward
perform(ActionMapping mapping, ActionForm form, HttpServletRequest request,
HttpServletResponse response)

throws IOException, ServletException {

RegistrationForm
info = (RegistrationForm)form;

ActionErrors errors = info.validate(mapping, request);

saveErrors(request, errors);

return mapping.findForward("success");

}"

May be useful.

$kala.

Hi!

I found out that
there is a attempt to provide some tutorial about validation by jakarta. But
nothing there yet.
http://jakarta.apache.org/struts/userGuide/dev_validator.html

$kala

I'm looking for
the same answer as you (probably). If you wanna use client side JavaScript validation,
this may help you.

Validation

Validation is already
a part of Struts.. it used to have a seat at when it was not: http://home.earthlink.net/~dwinterfeldt/.
Now it is also at: http://cvs.apache.org/viewcvs/jakarta-commons/validator/.

• files necessary
  to setup the validator:
  
  
  
  • validator-rules.xml
    (if you don't want to define own validator you don't need to toch it)
    
    
    
    
    • defines
      validation rules (+their Javascript) defined in org.apache.struts.validator.util.StrutsValidator
      such as:
      
      · field is required
      
      · specified length
      
      · matches a regular expression
      
      · email
      
      · credit card
      
      · server side type checking
      
      · date validation
      
      · other.. plus
      you may define your own validation rules as validation plugins
      
      
    
    
    
    
  
  
  • validation.xml
    (here you have to define validations for your specific formbeans)
    
    
    
    • defines
      global constants used by validation plugins
    
    
    • different
      validation rules can be defined for different locales by seting a
      formset
    
    
    • each
      formset defines group of properties specific for the form and their
      "limitations" with specific values e.g. :
      
      
      
      • form
        bean name
        
        
        
        • field
          name
          
          
          
          • required
            (true/false)
          
          
          • 
            mask (regular expresion)
          
          
          • minlenght
            (size)
          
          
          
          
        
        
        • field
          name
          
          
          
          • required
            (true/false)
          
          
          • email
          
          
          
          
        
        
        • etc.
        
        
        
        
      
      
      
      
    
    
    
    
  
  
  • web.xml
    
    
    
    
    • locates
      validator taglibs (probably)
    
    
    
    
  
  
  • struts-config.xml
    - this has to be added
    
    
    
    • Message
      Resources Definition - "
    
    
    • Plug
      Ins Configuration -
      
      
      
      
    
    
    • ApplicationResources.properties
      (+language versions) - define error messages such as errors.required,
      errors.minlength etc. (errors.maxlength={0} can not be greater than
      {1} characters) + header and footer
    
    
    
    
  
  
  
  


• custom validation
  routines can be created and added to the framework


• different validation
  rules can be defined for different locales


• support for
  user defined constants which can be used in some field attributes


• JavascriptValidatorTag
  - used to generate javascript validations on client side, based on the validation
  rules loaded by the Validator



• Usage
  
  
  
  • use as:
    
    
    
    • extend
      org.apache.struts.validator.action.ValidatorForm instead of org.apache.struts.action.ActionForm
    
    
    • form
      element's name attribute in the validation.xml should match action
      element's name attribute.
    
    
    
    
  
  
  • or as:
  
  
  
  
  • extend
    the ValidatorActionForm
  
  
  • action
    element's 'path' attribute from the struts-config.xml which should match
    the form element's name attribute in the validation.xml
  
  
  
  
  
  

Internationalization

• Validation rules
  for forms can be grouped under a FormSet in the validation.xml file.


• FormSet has
  language, country, and variant attributes that correspond with the java.util.Locale
  class

Pluggable Validators

There are predefined validators as shown above, but you may define your own
validator. Then you define it as:

Example Validator Configuration from validation.xml.

classname="org.apache.struts.validator.util.StrutsValidatorUtil"

method="validateRequired"

msg="errors.required"/>

Have a Submit
Button in a Form not Perform Validation

If you want to turn off the validation for a specific submit button like the
html:cancel tag, you can set the bCancel variable to true for the JavaScript
validation not to execute and bCancel to false for it to execute.

onclick="bCancel=false;">

Client
side validation

I'm still not
sure about how to get JS validation work at client side.. if it is only in presence
of "onsubmit="return validateRegistrationForm(this);" in the
form tag of jsp... will see. I have downloaded older Validator from http://home.earthlink.net/~dwinterfeldt/archive/
and there is working example but with no extra comment and without source codes..
But I have already seen validation window appear at client, telling me what
should be and is not valid :)) So, it works :))

Now
I'm waiting for these questions to be answered from David Winterfeldt:

• Where can I
  find some working example (+source code of Actions etc!) to see how it (the
  validation) works?


• Is there any
  serious tutorial about "validation in struts" ?


• Where can I
  find more obout validation at jakarta home page ? (I found only: http://cvs.apache.org/viewcvs/jakarta-commons/validator/)
  
  

When answered,
I'll publish.

Hope helped a bit.
Digging around :))

$kala.

Hi Heema,

Struts has so-called ActionForm objects which acts like a filter before a form gets POSTed. You can do validation by overiding the validate() method and providing your own code. Just tell Struts that this form has a corresponding ActionForm object (this is done in struts-config.xml), and Struts will do the binding automatically for you.

Hope that helps.

-- Val