How to check dynamic class usage in very big java project

Question

I have a pretty big Java project with very low code coverage, and want to increase the number of test cases. Is there any way to measure which classes are used the most in runtime? This way we can measure which classes we need to cover first. The project is a web app running over tomcat & websphere if it is important.

Answer 1

Yes.

There are tools that replace the standard Classloader so that they instrument classes for coverage as those classes are loaded.

I think that Clover and Emma were the best ones that I've used. Emma is free, but doesn't appear to be very active since 2005.