Compilation of Cross package classes

[Aditya Patro]

How does Java compiler do the compilation of two interdependent java classes in two different packages?

[Stan James]

Even within a package a pair of classes that reference each other must be tricky. I'd have to guess the compiler works part way through each class, just enough to understand the public interfaces, then goes back to work through every line of code.

Circular references are usually a warning sign about your design. They are unavoidable in some situations, so they aren't a fatal sign. (It's much worse in C, I guess.) But circular dependencies between packages are a "pretty bad" sign. Robert Martin has written extensively on dependency management. This paper talks about it; Google for more articles by the same author.

[Nicholas Jordan]

RE:

OO Design Quality Metrics
An Analysis of Dependencies
By Robert Martin

Good piece, professionally done. I saved it.

[Stan James]

The book we recommend at least once a week: Agile Software Development, Patterns Principles and Practices is largely about dependency management. The metrics in that article are closely related to the last half of the book. A free tool called JDepends examines compiled code and reports all the metrics. A commercial tool called Lattix does even more with neat graphics and "what if" analysis for fixing dependency problems.
[ September 04, 2007: Message edited by: Stan James ]