No matter what UI platform you use, complex EL is more trouble than it is worth. If at all possible,
you should construct the URL in the UI Model bean, not on the web page template or in JavaScript. That way the template can be much simpler (for example 'href="#{hotel.bookingURL}"' and if you do have problems, you can set a breakpoing on the "getBookingURL method in
Java to more easily determine what went wrong and why.