Separating Concerns with Hyper/JTM: An Experience Report

In earlier work, we conducted an exploratory investiga- tion of concerns in two existing Java TM packages: jFTPd and gnu.regexp. Two separate developers marked con- cerns in the source for each package: these concerns were then compared and analyzed. In this paper, we describe the next step of our investigations: the use of the IBM Hyper/J TM tool to separate and configure the identified con- cerns. We describe the various kinds of hyperspaces, hy- permodules, hyperslices, and concern mappings we used to describe our previously identified concerns. We also discuss code restructurings we used to enable the captur- ing and composition of concerns.