JavaWiz: A Trace-Based Graphical Debugger for Software Development Education

Software development education faces challenges in teaching abstract and complex programming concepts. Since problems in comprehension can lead to decreased student engagement, we introduce JavaWiz: an educational graphical debugger that addresses these challenges by combining traditional debugging functionality with intuitive, dynamic visualizations of program state and run-time behavior. JavaWiz's key features include real-time visualization of heap, stack, and static fields; automatically generated flow charts; interactive representations of data structures; and unique time-travel debugging capabilities. Its step-by-step visual exploration of code execution, including the ability to step backward, bridges the gap between abstract concepts and concrete program understanding. We present the tool's visualization components in detail and discuss its applications in teaching. Lecturers report positive influence on their in-class demonstrations and initial student feedback reinforces the tool's usefulness for program comprehension.