Abstract
Object-oriented software is designed by introducing classes and their relationships. When software is being executed, however, a developer loses sight of the classes he created during the design and coding of the software. This paper describes a tool that visualizes the program behaviour during execution. For Java programs this tool, called Trace- Vis, can collect relevant program execution events, like object creation, method entries and method exits. It uses byte-code instrumentation techniques to extract this information. The resulting trace of events is visualized using a dynamic call graph and a timeline representation. These views can be customized by selecting a time range in the execution, filtering the events, and manipulating the graphic representation. Some use cases for Trace Vis are presented.