Java EE (Java Enterprise Edition) General Discussion

As the subject say:

within the JSF-View I got one booleanCheckbox like this:

<h:selectBooleanCheckbox  value="#{backBean.valid}" />

I got some other checkboxes that are disabled on weather the first checkbox is active or not.
Because "#backBean.valid" looks like a expression, I tried out with a standard statement *( ! )* to negate the expression:

#!{backBean.valid}

And it doesnt work. I don't like to put some Java-Code <% .... %> within the JSP, because this says to me, that JSF is not very
helpful.

Any better ideas ?