Distribution Map

Understanding large software systems is a challenging task, and to support it many approaches have been developed. Often, the result of these approaches categorize existing entities into new groups or associates them with mutually exclusive properties. In this paper we present the distribution map as a generic technique to visualize and analyze this type of result. Our technique is based on the notion of focus, which shows whether a property is well-encapsulated or cross-cutting, and the notion of spread, which shows whether the property is present in several parts of the system. We present a basic visualization and complement it with measurements that quantify focus and spread. To validate our technique we show evidence of applying it on the result sets of different analysis approaches. As a conclusion we propose that the distribution map technique should belong to any reverse engineering toolkit

1 Introduction

Understanding large and complex software is a challenging task. To address this issue, various approaches have been proposed such as software visualization [21], [11], metrics [17], or clustering [2], [13]. Often, the result of these analyses categorizes existing entities into new groups or clusters, or associates them with mutually exclusive prop-erties. Understanding these results can be tedious as we have to understand how they are distributed over the sys-tem. Indeed, while these analyses are powerful to identify or characterize aspects of a large application, they often lack the support to understand the results they produce.