Analysis and Interactive Visualization of Software Bug Reports

A software Bug report contains information about the bug in the form of problem description and comments using natural language texts. Managing reported bugs is a significant challenge for a project manager when the number of bugs for a software project is large. Prior to the assignment of a newly reported bug to an appropriate developer, the triager (e.g., manager) attempts to categorize it into existing categories and looks for duplicate bugs. The goal is to reuse existing knowledge to fix or resolve the new bug, and she often spends a lot of time in reading a number of bug reports. When fixing or resolving a bug, a developer also consults with a series of relevant bug reports from the repository in order to maximize the knowledge required for the fixation. It is also preferable that developers new to a project first familiarize themselves with the project along with the reported bugs before actually working on the project. Because of the sheer numbers and size of the bug reports, manually analyzing a collection of bug reports is time-consuming and ineffective. One of the ways to mitigate the problem is to analyze summaries of the bug reports instead of analyzing full bug reports, and there have been a number of summarization techniques proposed in the literature. Most of these techniques generate extractive summaries of bug reports. However, it is not clear how useful those generated extractive summaries are, in particular when the developers do not have prior knowledge of the bug reports. In order to better understand the usefulness of the bug report summaries, in this thesis, we first reimplement a state of the art unsupervised summarization technique and evaluate it with a user study with nine participants. Although in our study, 70% of the time participants marked our developed summaries as a reliable means of comprehending the software bugs, the study also reports a practical problem with extractive summaries. An extractive summary is often created by choosing a certain number of statements from the bug report. The statements are extracted out of their contexts, and thus often lose their consistency, which makes it hard for a manager or a developer to comprehend the reported bug from the extractive summary. Based on the findings from the user study and in order to further assist the managers as well as the developers, we thus propose an interactive visualization for the bug reports that visualizes not only the extractive summaries but also the topic evolution of the bug reports. Topic evolution refers to the evolution of technical topics discussed in the bug reports of a software system over a certain time period. Our visualization technique interactively visualizes such information which can help in different project management activities. Our proposed visualization also highlights the summary statements within their contexts in the original report for easier comprehension of the reported bug. In order to validate the applicability of our proposed visualization technique, we implement the technique as a standalone tool, and conduct both a case study with 3914 bug reports and a user study with six participants. The experiments in the case study show that our topic analysis can reveal useful keywords or other insightful information about the bug reports for aiding the managers or triagers in different management activities. The findings from the user study also show that our proposed visualization technique is highly promising for easier comprehension of the bug reports

Leveraging Evolutionary Changes for Software Process Quality

Real-world software applications must constantly evolve to remain relevant. This evolution occurs when developing new applications or adapting existing ones to meet new requirements, make corrections, or incorporate future functionality. Traditional methods of software quality control involve software quality models and continuous code inspection tools. These measures focus on directly assessing the quality of the software. However, there is a strong correlation and causation between the quality of the development process and the resulting software product. Therefore, improving the development process indirectly improves the software product, too. To achieve this, effective learning from past processes is necessary, often embraced through post mortem organizational learning. While qualitative evaluation of large artifacts is common, smaller quantitative changes captured by application lifecycle management are often overlooked. In addition to software metrics, these smaller changes can reveal complex phenomena related to project culture and management. Leveraging these changes can help detect and address such complex issues. Software evolution was previously measured by the size of changes, but the lack of consensus on a reliable and versatile quantification method prevents its use as a dependable metric. Different size classifications fail to reliably describe the nature of evolution. While application lifecycle management data is rich, identifying which artifacts can model detrimental managerial practices remains uncertain. Approaches such as simulation modeling, discrete events simulation, or Bayesian networks have only limited ability to exploit continuous-time process models of such phenomena. Even worse, the accessibility and mechanistic insight into such gray- or black-box models are typically very low. To address these challenges, we suggest leveraging objectively [...]Comment: Ph.D. Thesis without appended papers, 102 page

Image-Schematic Metaphors in Software Visualization

Software visualization (SoftVis) is widely used to facilitate the process of obtaining an in-depth understanding of complex software systems. SoftVis designers can draw on a wide pool of pre-existing conceptual metaphors that model the abstract target domain to tangible source domains. As regular user-centered design methods do not provide guidance on choosing etaphorical mappings, SoftVis designers choose conceptual metaphors primarily based on their subjective similarity to the underlying data structure. We want to include image-schematic metaphors in the SoftVis design process to provide designers with guidance on choosing visualization metaphors that are also in line with the users' mental model. This could allow SoftVis designers to make more data-driven design decisions and result in SoftVis that provides better insights

Visualization of OSGi Based Software Architectures in Virtual Reality

Classic software architecture visualizations such as UML diagrams widely used in practice but are not always the best solution, for example to get an high level overview of large component-based software systems. In this talk, we show other suitable technologies for software visualization to understand complex software architectures. Especially, we show how to visualize OSGi based software architectures in Virtual Reality (VR) using VR headsets. We address the question, how software visualizing can help during the development process and what are the resulting benefits for developers and software testers. We focus on four aspects: Development, evaluation, quality assurance, and visualization technology. We demonstrate software visualization using the software ''IslandViz'', which visualizes OSGi based software systems using an island metaphor, where islands on a virtual water level represents OSGi bundles, regions on the islands represents packages, and buildings represents classes. We describe how to get all relevant data for the visualization by repository mining on the whole source tree and data mining on source code level. We store all data in a graph database for further analysis and visualization. Through software visualization we were able to answer many important questions, which have already taken a lot of time in development and test-phases. In addition, it's very important to make the software architecture tangible, which makes it easier way to talk about technical problems in teams formed by people with different knowledge, communications skills, and backgrounds

Quality Properties of Execution Tracing, an Empirical Study

The authors are grateful to all the professionals who participated in the focus groups; moreover, they also express special thanks to the management of the companies involved for making the organisation of the focus groups possible.Data are made available in the appendix including the results of the data coding process.The quality of execution tracing impacts the time to a great extent to locate errors in software components; moreover, execution tracing is the most suitable tool, in the majority of the cases, for doing postmortem analysis of failures in the field. Nevertheless, software product quality models do not adequately consider execution tracing quality at present neither do they define the quality properties of this important entity in an acceptable manner. Defining these quality properties would be the first step towards creating a quality model for execution tracing. The current research fills this gap by identifying and defining the variables, i.e., the quality properties, on the basis of which the quality of execution tracing can be judged. The present study analyses the experiences of software professionals in focus groups at multinational companies, and also scrutinises the literature to elicit the mentioned quality properties. Moreover, the present study also contributes to knowledge with the combination of methods while computing the saturation point for determining the number of the necessary focus groups. Furthermore, to pay special attention to validity, in addition to the the indicators of qualitative research: credibility, transferability, dependability, and confirmability, the authors also considered content, construct, internal and external validity

Enhanced Version Control for Unconventional Applications

The Extensible Markup Language (XML) is widely used to store, retrieve, and share digital documents. Recently, a form of Version Control System has been applied to the language, resulting in Version-Aware XML allowing for enhanced portability and scalability. While Version Control Systems are able to keep track of changes made to documents, we think that there is untapped potential in the technology. In this dissertation, we present novel ways of using Version Control System to enhance the security and performance of existing applications. We present a framework to maintain integrity in offline XML documents and provide non-repudiation security features that are independent of central certificate repositories. In addition, we use Version Control information to enhance the performance of Automated Policy Enforcement eXchange framework (APEX), an existing document security framework developed by Hewlett-Packard (HP) Labs. Finally, we present an interactive and scalable visualization framework to represent Version-Aware-related data that helps users visualize and understand version control data, delete specific revisions of a document, and access a comprehensive overview of the entire versioning history