Struts and validation question ?

Question

hi,
i am using the struts framework for my application, i have a simple jsp logon page (username, password)
i have defined a validtion.xml file
<?xml version="1.0" encoding="ISO-8859-1" ?>
<!DOCTYPE form-validation PUBLIC
          "-//Apache Software Foundation//DTD Commons Validator Rules Configuration 1.0//EN"
          "http://jakarta.apache.org/commons/dtds/validator_1_0.dtd">
<!--
    Validation Rules for the Struts Example Web Application
    $Id: validation.xml,v 1.8 2003/05/25 22:51:20 dgraham Exp $
-->
<form-validation>
    <!-- ========== Default Language Form Definitions ===================== -->
    <formset>
        <form name="logonForm">
            <field property="username"
                    depends="required, minlength,maxlength">
                <arg0   key="prompt.username"/>
                <arg1   key="${var:minlength}" name="minlength"
                   resource="false"/>
                <arg2   key="${var:maxlength}" name="maxlength"
                   resource="false"/>
                <var>
                    <var-name>maxlength</var-name>
                    <var-value>16</var-value>
                </var>
                <var>
                    <var-name>minlength</var-name>
                    <var-value>3</var-value>
                </var>
            </field>
            <field property="password"
                    depends="required, minlength,maxlength">
                <arg0   key="prompt.password"/>
                <arg1   key="${var:minlength}" name="minlength"
                   resource="false"/>
                <arg2   key="${var:maxlength}" name="maxlength"
                   resource="false"/>
                <var>
                    <var-name>maxlength</var-name>
                    <var-value>16</var-value>
                </var>
                <var>
                    <var-name>minlength</var-name>
                    <var-value>3</var-value>
                </var>
            </field>
        </form>
        <form name="registrationForm">
            <field property="fromAddress"
                    depends="required,email">
                <arg0   key="prompt.fromAddress"/>
            </field>
            <field property="fullName"
                    depends="required">
              <arg0     key="prompt.fullName"/>
            </field>
            <field property="replyToAddress"
                    depends="email">
                <arg0   key="prompt.replyToAddress"/>
            </field>
            <field property="username"
                    depends="required">
              <arg0     key="prompt.username"/>
            </field>
        </form>
    </formset>
</form-validation>i have also the validation-rules.xml file provided by the struts lib.
i would like to force the content of 'username' property to be alphabetic.
i guess i have to create my own element
<validator name="alphabeticString"...> inside the validation-rules.xml file, but i am newbie in javascript programming.
i have tree question.
1) why the validation code inside the validator element is written in javascript since it's not going to be executed at client side???
2)can i use java instead ? (to code teh validation ...)
3)has anyone got a code to solve this problem ?
thanks for your help

Answer 1

i would like to force the content of 'username' property to be alphabetic.
i guess i have to create my own element
<validator name="alphabeticString"...> inside the validation-rules.xml file,
but i am newbie in javascript programming.Not for something that simple... there's a validator rule called mask, which takes a regular expression as an argument, so if you want only a-z: "[a-zA-Z]*" should work.
1) why the validation code inside the validator element is written in javascript since it's not going to be executed at client side???It is validated on the client, or can be. You have to include the javascript with the html:javascript tag library tag and specify the form name. Then you need to put the onsubmit="return validateFormName();" attribute in the form tag. If JS isn't supported, it'll still default back to the server side validation.
2)can i use java instead ? (to code teh validation ...)Don't include the JS stuff.