I received a dump of Java codebase which had multiple modules and I needed to analyse it’s structure. The following tool did quite a good job:

https://github.com/gdela/socomo

Basically the idea is to run it inside a Java project using a maven command and it creates HTML file which denotes the high level structure of the code.

Note: Stan4J is also a very good tool which does similar job but allows deeper analysis (upto 500 classes only)