This paper promotes the use of a mathematical concept lattice based upon the binary relation of accesses between methods and fields as a novel visualization of individual JAVA classes. We demonstrate in a detailed real-life case study that such a lattice is valuable for reverse-engineering purposes, in that it helps reason about the interface and structure of the class and find errors in the absence of source code. Our technique can also serve as a heuristic for automatic feature categorization, enabling it to assist efforts of re-documentation.