Which Java based web ui framework to use? [closed]

Question

• Wicket
• Click
• GWT
• Vaadin

As I understand them, these frameworks all enable gui components to be created using java (with all its benefits) without having to do lots of html/javascript.

As well as considering the technical factors, I am also interested to hear if any are gaining popularity fast. Is a particular framework is becoming the leader of the pack, this will also effect the decision.