Splitting your class diagram often makes it confusing especially if you split it by layer and not by feature..
if i did end up splitting the class diagram (although at first attempt i would try to avoid it) , i would perhaps switch it by feature...so a bunch of jsps, controllers, services,...etc..which serve a common feature..end up in related diagrams..
splitting it by layer..would require the examiner to go through multiple diagrams to understand each feature of your solution...
But before you do something..hear from others as well..