Evaluation of Global Hierarchical Object Graphs for Coding Activities: a Controlled Experiment1

Abstract

A diagram of the runtime structure shows objects and their relations and complements diagrams of the code structure. One such diagram, the Ownership Object Graph (OOG), is a global object graph that conveys architectural hierarchy based on annotations in the code. In this work, we ask the research question: do developers benefit from using OOGs, in addition to class diagrams, during their coding activities? We conducted the first controlled experiment evaluating global object graphs in relation to class diagrams. We observed 10 developers, for 3 hours each, perform coding activities on a framework application. Developers struggled with many questions about the object structure. Two developers who used OOGs completed the three tasks compared to only one developer who used only class diagrams. Developers who used OOGs performed their activities in less time by 22–60%, and browsed less irrelevant code by 10–60%, compared to those who used only class diagrams.