Larry A. Barowski

An extensible framework for providing dynamic data structure visualizations in a lightweight IDE

A framework for producing dynamic data structure visualizations within the context of a lightweight IDE is described. Multiple synchronized visualizations of a data structure can be created with minimal coding through the use of an external viewer model. The framework supplies a customizable viewer template as well as high-level APIs to a graph drawing library and the Java Debugger Interface. Initial classroom use has demonstrated the frameworks ease of use as well as its potential to as an aid to student learning.

Experimental evaluation of animated-verifying object viewers for Java

Although many visualization techniques have been shown to be pedagogically effective, they are still not widely adopted. The reasons include: lack of suitable methods of automatic-generation of visualizations, lack of integration among visualizations, and lack of integration with basic integrated development environment (IDE) support. To effectively use visualizations when developing code, it is useful to automatically generate multiple synchronized views without leaving the IDE. The jGRASP IDE provides object viewers that automatically generate dynamic, state-based visualizations of objects and primitive variables in Java. Such seamless integration of a lightweight IDE with a set of pedagogically effective software visualizations is unique and is currently unavailable in any other environment. Multiple instructors have reported positive anecdotal evidence of their usefulness. We conducted formal, repeatable experiments to investigate the effect of these viewers for singly linked lists on student performance and we found a statistically significant improvement over traditional methods of visual debugging that use break-points.

Extraction and use of class dependency information for Java

In this paper, a method for extracting class dependency information from Java class files is described. Advantages and disadvantages of using this method are discussed The problems of virtual dependence and synthetic methods are explained, and solutions offered. A convenient user interface is presented for making use of the dependency information in the form of an interactive UML class diagram, which is automatically generated from Java class files. This interface is a component of the jGRASP integrated development environment.

Using the debugger as an integral part of teaching CS1

Traditionally, using a debugger has had the connotation of finding and removing defects. In this paper and presentation, we explore the use of a modern integrated debugger as a program understanding tool for novice programming students in CS1. With the move to Java in the first course, instructors and students are faced with either ignoring the details of object-oriented concept or with explaining the concepts in a way that novices can understand. We show how the debugger can be used to depict the initial construction of an object, the objects inherited members, and polymorphic calls to the objects methods. Although each of these concepts can be difficult for beginning programmers, using the debugger to explicitly illustrate these concepts provides students with an opportunity for a much deeper understanding of their programs.

Robust Generation of Dynamic Data Structure Visualizations with Multiple Interaction Approaches

jGRASP has three integrated approaches for interacting with its dynamic viewers for data structures: debugger, workbench, and text-based interactions that allow individual Java statements and expressions to be executed/evaluated. These approaches can be used together to provide a complementary set of interactions with the dynamic viewers. Data structure identification and rendering were tested by examining examples from 20 data structure textbooks. Controlled experiments with CS2 students indicate that the viewers can have a significant positive impact on student performance. The overall result is a flexible environment for interacting with effective dynamic data structure visualizations generated by a robust structure identifier.

The role of software measures and metrics in studies of program comprehension

Many studies have been conducted into how programmers comprehend software. Models based on these studies have pointed to top-down, bottom-up, and mixed models for describing the comprehension process. In most of these studies, however, a key element of the experiment is largely ignored: the underlying nature of the software being examined by the programmers. This paper discusses software measurements and metrics that must be considered as factors when conducting comprehension

Scalable visualizations to support reverse engineering: a framework for evaluation

Visualizations of software can be utilized in varying degrees throughout the software development cycle as aids to comprehension, analysis, and measurement. This research focuses on the experimental evaluation and refinement of a set of scalable visualizations that show promise for improving the overall software process. The roles which visualizations may play during reverse engineering and maintenance are of particular interest. This research also investigates the manner in which software visualizations are used in practice by software professionals. Partners from government and industry have agreed to participate by providing access to appropriate production software. This paper will describe a framework for evaluating visual techniques and investigating their practical use and application.

Bringing J2ME industry practice into the classroom

This paper describes efforts to use industry wireless software development practices in the classroom. Nokias OK Java 2 Platform Micro Edition (J2ME) application certification program was chosen for use in a core set of wireless software engineering courses. The adaptation process included 1) modifying Nokia OK application standards for classroom use as examples of what is expected of industry-quality software; 2) incorporating Nokia OK software development tools into a student-friendly software development environment; and 3) implementing in-house Nokia OK certification procedures as a basis for assessing student projects and providing feedback.

Tool support for reverse engineering multi-lingual software

Multi-lingual software systems are those in which the component modules are implemented in multiple languages. Reverse engineering such systems raises several issues, particularly with regard to providing automated tool support for the process. GRASP is a prototype software engineering tool designed to provide visualization of software control structure, complexity, and architecture. The paper describes GRASP and its use in reverse engineering multi-lingual software systems.

Visual support for incremental abstraction and refinement in Ada 95

1. ABSTRACT GRASP is a software engineering tool which uniquely combines a source code diagramming technique, the control structure diagram (CSD), with other comprehension aids such as complexity visualization, syntax coloring and source code folding. The synergistic combination of these features in GRASP has the potential to be a powerful aid in any activity where source code is expected to be read. The primary focus of GRASP is to improve the comprehension efficiency of software and, as a result, improve reliability and reduce costs during design, implementation, testing, maintenance and reengineering.