Re: Unique Validator in Foreach loop

[Paul Ferraro]

Off the top of my head, try something like this:
public class UniqueValidator implements IValidator
{
   private Set valueSet = new HashSet();
   public toObject(IFormComponent field, String input) throws 
ValidatorException
   {
      // Preliminary validation

      // Validate uniqueness
      if (valueSet.contains(input))
      {
         // Duplicate field!
         throw new ValidatorException(field.getDisplayName() + " must 
be unique.");
      }

      valueSet.add(input);
   }
// ...
}
Then make sure that your UniqueValidator bean is request scoped.
Paul
Denis Souza wrote:
Hi,

I have a Foreach loop in which I want to validate the fields inside it. For
any regular required or minimum-length validation that's fine, but I'm
trying to build a validator that checks if each field is unique. For
example, let's say the only field I have inside the foreach loop is a field
for a name. Let's say this loop iterates 5 times so that there would be 5
text fields rendered. I would like each of these "names" to be unique.

What I have done so far is, I created a validator called UniqueValidator and
I'm passing it the same list of objects to perform the validation that I use
in the foreach loop. This implementation causes two problems:

1) Tapestry is updating the list of objects with the submitted values only
after the validations run, so I'm actually checking for uniqueness in a
deprecated list. I have to be able to see the values that were just
submitted in case the user changes more than one value.

2) I can't tell where in the object list is the field that is being
validated, so I can't skip the item on the list that is being checked and I
end up returning validation errors even if a name is entered only once in
the list. I can work around this by checking if there is more than one
object in the list that is the same as the input, but I don't think it's
such an elegant solution.

Any ideas?

Thanks,
Denis

 


---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]