Create your own valiadtion rules is the powerful features in validator framework.To create your own validator rules and use it in a struts DynamicForm.Your web application may require a specific validation that is not provided by the struts validation framework. The struts validator framework provides a simple interface for creating your own custom validations that can easily be plugged into the validation framework.

 
You need to perform the following step :-

1.  Create a java class and  a new validation rule method in this class.
2.  Create an entry in the validation-rules.xml file.
3.  Applying new validation rule to form bean field inside validation.xml file.
4.  Add messages to the ApplicationResources.properties file.
5.  
Add a new <form> tag or modify an existing tag to indicate that this rule is to be applied when the form is validated.

Your own validator rules method get passed a bean ,validatorAction , Field .

Step 1.  Create a java class and  a new validation rule method in this class.

public class CustomValidatorRulesExample {  
public static boolean validatePhone(Object bean, ValidatorAction action, Field field, 
ActionMessages errors, Validator validator,	HttpServletRequest request) {	
-----------	}
} 

Step 2. Create an entry in the validation-rules.xml file.

<validator name="phone" classname="r4r.co.in.CustomValidatorRulesExample" method="validatePhone"  
 methodParams="java.lang.Object,org.apache.commons.validator.ValidatorAction,  
 org.apache.commons.validator.Field,org.apache.struts.action.ActionMessages,     
 org.apache.commons.validator.Validator,javax.servlet.http.HttpServletRequest" depends=""
 msg="errors.phone"/>

Step 3. Applying new validation rule to form bean field inside validation.xml file.

<field property="phone" depends="required,phone">    
<arg0 key="form.mobile" />
</field>


Step 4. Add messages to the ApplicationResources.properties file.

# Resources for parameter 'r4r.co.in.ApplicationResources'
# Project OwnValidatorRulesExample
# -- standard errors --errors.header=<UL>
errors.prefix=<LI>
errors.suffix=</LI>errors.footer=</UL>
# -- validator --
errors.invalid={0} is invalid.
errors.maxlength={0} can not be greater than {1} characters.
errors.minlength={0} can not be less than {1} characters.
errors.range={0} is not in the range {1} through {2}.
errors.required={0} is required.
errors.byte={0} must be an  byte.
errors.date={0} is not a date.
errors.double={0} must be an double.
errors.float={0} must be an float.
errors.integer={0} must be an integer.
errors.long={0} must be an long.
errors.short={0} must be an short.
errors.creditcard={0} is not a valid credit card number.
errors.email={0} is an invalid e-mail address.
# -- other --
errors.cancel=Operation cancelled.
errors.detail={0}errors.general=The process did not complete. Details should follow.
errors.token=Request could not be completed. Operation is not in sequence.
form.phone=Telephone no 
errors.phone='{0}' field is not a valid Phone no.
error.phoneNumber.required =Phone number is required.

Step 5.Add a new <form> tag or modify an existing tag to indicate that this rule is to be applied when the form is validated.




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