Here's an example:

  form.add(new TextField<Date>("whatever", new PropertyModel<Date>(event, "date"))
.add(DateValidator.maximum(new Date())));

While I was thinking about this, I started to wonder if a fluent interface would be able to take care of all of this through type inference. And I think it does. I quickly prototyped a fluent FormBuilder, and this is what the above example looks alike now:

addTextField("whatever")
 .forModelOfType(Date.class)
 .validatedBy(DateValidator.maximum(new Date()))
 .forProperty("date").of(event) 
 .to(form);

And all the brackets are magically gone again... Now don't be fooled by the simplicity here. The compiler and IDE will support you in exactly the same way as in the first code example. You will not be able to add an IValidator type of validator, as the screenshot below illustrates. 

Now, I have to say that the current incarnation of this fluent API is less than great. One of the things I should have done already - but haven't done yet - is to be able to drop .forModelOfType(...) in case you pass the property type in the forProperty(...) construct. So something like this: .forProperty("date").ofType(Date.class).of(event). But that's details. In general, I think this could work. What do you think?