Evaluation criteria of software visualization systems used for program comprehension

The program understanding task is usually very time and effort consuming. In a traditional way the code is inspected line by line by the user without any kind of help. But this becomes impossible for larger systems. Some software systems were created in order to generate automatically explanations, metrics, statistics and visualizations to describe the syntax and the semantics of programs. This kind of tools are called Program Comprehension Systems. One of the most important feature used in this kind of tool is the software visualization. We feel that it would be very useful to define criteria for evaluating visualization systems that are used for program comprehension. The main objective of this paper is to present a set of parameters to characterize Program Comprehension-Oriented Software Visualization Systems. We also propose new parameters to improve the current taxonomies in order to cover the visualization of the Problem Domain.FC

Algorithm-Program Visualization Model : An Intergrated Software Visualzation To Support Novices' Programming Comprehension

Computer programming is the essential foundation for the other basic skills in Information Technology knowledge areas. Success in this field requires complex knowledge and skill. Mostly, conventional programming courses have been delivered based on the programming textbooks with professional developer tools which focus on the syntax or semantic through the coding task. The role of Software Visualization (SV) has been involved to overcome the complexity and problems in the learning programming. It represents the abstractness of the program in graphical views or illustrations of its entities. Nevertheless, the outcome of the learning still remains poor. Through multi-methodological approach, this research aimed to improve the effectiveness of the visualization as the program comprehension tool. It is found that the interrelated tasks in the programming process, with its various abstractions, and timing in delivering the feedback, need to be addressed with the equal attention in learning to program. Taking into account from those main issues, this study introduces the new model of integrated algorithm-program visualization (ALPROV) for developing program comprehension tool. This model is then to be used in the prototype tool development that is called 3De-ALPROV (Design Development Debug – Algorithm Program Visualization). The efficacy evaluation of the prototype is based on pre- and post- test of the students’ programming performance. The programming performances from the treatment and control group are compared to analyze the effect of using the proposed tool in learning programming. Respondents are first-year bachelor students who lack of programming knowledge and experience.Analysis proved that using the program comprehension tool, which has been developed using integrated ALPROV model significantly improved the treatment group’s programming performance. Conducting other experiments as the extended study, such as seek for a larger group of respondents, conduct the experiments throughout the necessary period, and use various methods for programming assessment and analysis may improve the findings of this research

Simplificando la comprensión de programas a través de la interconnexión de dominios

The program understanding task is usually time and effort consuming. In a traditional way the code is inspected line by line by the user without any kind of help. But this becomes impossible for large systems. Some software systems were created in order to generate automatically explanations, metrics, statistics and visualizations to describe the syntax and the semantic of programs. These kind of tools are Program Comprehension systems. One of the most important feature used in this kind of tool is the software visualization. We feel that would be very useful to define criterion to evaluate visualization systems that are used for program comprehension. The main objective of this paper is to describe and discuss a set of evaluation parameters for this kind of systems.FC

Strategies for program inspection and visualization

The aim of this paper is to show the strategies involved in the implementation of two tools of PCVIA project that can be used for Program Comprehension. Both tools use known compiler techniques to inspect code in order to visualize and understand programs’ execution. On one hand we convert the source program into an internal decorated (or attributed) abstract syntax tree and then we visualize the structure traversing it, and applying visualization rules at each node according to a pre-defined rule-base. No changes are made in the source code, and the execution is simulated. On the other hand, we traverse the source program and instrument it with inspection functions. Those inspectors provide information about the function-call flow and data usage at runtime (during the actual program execution). This information is collected and gathered in an information repository that is then displayed in a suitable form for navigation. These two different approaches are used respectively by Alma (generic program animation system) and Cear (C Rooting Algorithm Visualization tool). For each tool several examples of visualization are shown in order to discuss the information that is included in the visualizations, visualization types and the use of Program Animation for Program Comprehension.FC

Metaviz : issues in software visualizing beyond 3D

Software visualization can play a significant role in program comprehension. A large number of visualization tools have been developed to support program comprehension. Traditionally, these tools are 2D representations. In recent years, 3D software visualization techniques have been introduced to support program comprehension. These techniques provide new approaches to visualizing and comprehending software system structures and their internal relationships. At the same time, they introduce new research challenges. The software metaphors, layout algorithms, and readability criteria generally applicable in 2D software visualization cannot directly be applied in 3D visualizations. In this thesis, we present our research on the use of a new metaphor based on energy fields using the Metaballs 3D modeling and visualization technique. We also present grouping and layout algorithms, specially designed for 3D Metaballs based software visualization. These are built into Metaviz, a software visualization tool, which we have designed and implemented as part of our larger program comprehension environment, CONCEPT. Using Metaviz, we also show examples that illustrate how these visualization techniques, when combined with program slicing and metric based analysis, provide guidance during software comprehension during the testing and maintenance phrase

AspectMaps: Extending Moose to visualize AOP software

International audienceWhen using aspect-oriented programming the application implicitly invokes the functionality contained in the aspects. Consequently program comprehension of such a software is more intricate. To alleviate this difficulty we developed the AspectMaps visualization and tool. AspectMaps extends the Moose program comprehension and reverse engineering platform with support for aspects, and is implemented using facilities provided by Moose. In this paper we present the AspectMaps tool, and show how it can be used by performing an exploration of a fairly large aspect-oriented application. We then show how we extended the FAMIX meta-model family that underpins Moose to also provide support for aspects. This extension is called ASPIX, and thanks to this enhancement Moose can now also treat aspect-oriented software. Finally, we report on our experiences using some of the tools in Moose; Mondrian to implement the visualization, and Glamour to build the user interface. We discuss how we were able to implement a sizable visualization tool using them and how we were able to deal with some of their limitations. Note: This paper uses colors extensively. Please use a color version to better understand the ideas presented here

Code inspection approaches for program visualization

The aim of this paper is to show the approaches involved in the implementation of two tools of PCVIA project that can be used for Program Comprehension. Both tools use known compiler techniques to inspect code in order to visualize and understand programs’ execution but one of them modifies the source code and the other not. In the non-invasive approach, we convert the source program into an internal decorated (or attributed) abstract syntax tree and then we visualize the structure traversing it, and applying visualization rules at each node according to a pre-defined rule-base. No changes are made in the source code, and the execution is simulated. In the invasive approach, we traverse the source program and instrument it with inspection functions. Those functions, also known as inspectors, provide information about the function-call flow and data usage at runtime (during the actual program execution). This information is collected and gathered in an information repository that is then displayed in a suitable form for navigation. These two different approaches are used respectively by Alma (generic program animation system) and CEAR (C Rooting Algorithm Visualization tool). For each tool several examples of visualization are shown in order to discuss the information that is included in the visualizations, visualization types and the use of Program Animation for Program Comprehension.FC

A document-like software visualization method for effective cognition of c-based software systems

It is clear that maintenance is a crucial and very costly process in a software life cycle. Nowadays there are a lot of software systems particularly legacy systems that are always maintained from time to time as new requirements arise. One important source to understand a software system before it is being maintained is through the documentation, particularly system documentation. Unfortunately, not all software systems developed or maintained are accompanied with their reliable and updated documents. In this case, source codes will be the only reliable source for programmers. A number of studies have been carried out in order to assist cognition based on source codes. One way is through tool automation via reverse engineering technique in which source codes will be parsed and the information extracted will be visualized using certain visualization methods. Most software visualization methods use graph as the main element to represent extracted software artifacts. Nevertheless, current methods tend to produce more complicated graphs and do not grant an explicit, document-like re-documentation environment. Hence, this thesis proposes a document-like software visualization method called DocLike Modularized Graph (DMG). The method is realized in a prototype tool named DocLike Viewer that targets on C-based software systems. The main contribution of the DMG method is to provide an explicit structural re-document mechanism in the software visualization tool. Besides, the DMG method provides more level of information abstractions via less complex graph that include inter-module dependencies, inter-program dependencies, procedural abstraction and also parameter passing. The DMG method was empirically evaluated based on the Goal/Question/Metric (GQM) paradigm and the findings depict that the method can improve productivity and quality in the aspect of cognition or program comprehension. A usability study was also conducted and DocLike Viewer had the most positive responses from the software practitioners

Program Visualization: An exploration of graph based visualizations to assist in student learning and programmatic evaluation

As computer science students develop more complex programs at the end of their first year of course work, comprehending the complex and varied interactions of program execution, potential control flow and data relationships become more and more difficult. Additionally, for instructors when evaluating student\u27s programs, a simplified view of more complex (longer) programs is desirable. This thesis explores algorithms to create a tool for students that provides a simplified view of these concepts via visualization. The tool created for this thesis provides interactive visual representations of student programs. This allows for a simplified representation of the entire program along with depth exploration options to examine potential control flow and data access/mutations. The following is an exploration of program visualization, with a focus on usability in an educational setting. Two main approaches will be discussed. The first attempts to visualize the call graph of a running program by showing what methods call what other methods, and the frequency in which they are invoked. The second shows all potential paths through a non-running program, by viewing the program on a per-method level. This approach also includes information about how methods interact with data. As a test case this thesis focuses on a spell check program which builds a binary search tree dictionary then searches it for input strings and provides correction suggestions if the input is not found in the dictionary. We present an evaluation of our tool via creating visualizations of four different student implementations of this program. These visualizations are then analyzed by computer science faculty to identify common threads throughout all submissions, as well as areas where individual students struggled or excelled. Additionally visualizations are used as a tool in a lecture instructing students about binary search trees. The students provide feedback as to the effectiveness of the visualizations and their comprehension of the material. We conclude that program visualization is a difficult task, especially when students are unused to visualizing control flow. Results indicate potential for use as both a student and instructor tool, though further research is required to identify optimal usage