Live visualization of GUI application code coverage with GUITracer

The present paper introduces the initial implementation of a software exploration tool targeting graphical user interface (GUI) driven applications. GUITracer facilitates the comprehension of GUI-driven applications by starting from their most conspicuous artefact - the user interface itself. The current implementation of the tool can be used with any Java-based target application that employs one of the AWT, Swing or SWT toolkits. The tool transparently instruments the target application and provides real time information about the GUI events fired. For each event, call relations within the application are displayed at method, class or package level, together with detailed coverage information. The tool facilitates feature location, program comprehension as well as GUI test creation by revealing the link between the application's GUI and its underlying code. As such, GUITracer is intended for software practitioners developing or maintaining GUI-driven applications. We believe our tool to be especially useful for entry-level practitioners as well as students seeking to understand complex GUI-driven software systems. The present paper details the rationale as well as the technical implementation of the tool. As a proof-of-concept implementation, we also discuss further development that can lead to our tool's integration into a software development workflow.