Facelets is a XML based view technology. The & is a special character in XML representing the start of an entity like & which ends with the ; character. You’d need to either escape it, which is ugly:
rendered="#{beanA.prompt == true && beanB.currentBase != null}"
or to use the and keyword instead, which is preferred as to readability and maintainability:
rendered="#{beanA.prompt == true and beanB.currentBase != null}"
See also:
- Java EE 6 tutorial – Operators in EL
Unrelated to the concrete problem, comparing booleans with booleans makes little sense when the expression expects a boolean outcome already. I’d get rid of == true:
rendered="#{beanA.prompt and beanB.currentBase != null}"