A newcomer to a software project must typically come up-to-speed on a large, varied amount of information about the project before becoming productive. Assimilating this information in the open-source context is difficult because a newcomer cannot rely on the mentoring approach that is commonly used in traditional software developments. To help a newcomer to an open-source project become productive faster, we propose Hipikat, a tool that forms an implicit group memory from the information stored in a project’s archives, and that recommends artifacts from the archives that are relevant to a task that a newcomer is trying to perform. To investigate this approach, we have instantiated the Hipikat tool for the Eclipse open-source project. In this paper, we describe the Hipikat tool, we report on a qualitative study conducted with a Hipikat mock-up on a mediumsized in-house project, and we report on a case study in which Hipikat recommendations were evaluated for a task on Eclipse. 1.

Making effective use of the available display space has long been a fundamental issue in user interface design. We live in a time of rapid advances in available CPU power and memory. However, the common sizes of our computational display spaces have only minimally increased or in some cases, such as hand held devices, actually decreased. In addition, the size and scope of the information spaces we wish to explore are also expanding. Representing vast amounts of information on our relatively small screens has become increasingly problematic and has been associated with problems in navigation, interpretation and recognition. User interface research has proposed several differing presentation approaches to address these problems. These methods create displays that vary considerably, visually and algorithmically. We present a unified framework that provides a way of relating seemingly distinct methods, facilitating the inclusion of more than one presentation method in a single interface. Furthermore, it supports extrapolation between the presentation methods it describes. Of particular interest are the presentation possibilities that exist in the ranges between various distortion presentations, magnified insets and detail-in-context presentations, and between detail-incontext presentations and a full-zooming environment. This unified framework offers a geometric presentation library in which presentation variations are available independently of the mode of graphic representation. The intention is to promote the ease of exploration and experimentation into the use of varied presentation combinations.

This paper describes the SHriMP visualization technique for seamlessly exploring software structure and browsing source code, with a focus on effectively assisting hybrid program comprehension strategies. The technique integrates both pan+zoom and fisheye-view visualization approaches for exploring a nested graph view of software structure. The fisheye-view approach handles multiple focal points, which are necessary when examining several subsystems and their mutual interconnections. Source code is presented by embedding code fragments within the nodes of the nested graph. Finer connections among these fragments are represented by a network that is navigated using a hypertext link-following metaphor. SHriMP combines this hypertext metaphor with animated panning and zooming motions over the nested graph to provide continuous orientation and contextual cues for the user. The SHriMP tool is currently being evaluated in several user studies. Observations of users performing program understanding tasks with the tool are discussed.

Well-designed object-oriented programs typically consist of a few key classes that work tightly together to provide the bulk of the functionality. As such, these key classes are excellent starting points for the program comprehension process. We propose a technique that uses webmining principles on execution traces to discover these important and tightly interacting classes. Based on two medium-scale case studies – Apache Ant and Jakarta JMeter – and detailed architectural information from its developers, we show that our heuristic does in fact find a sizeable number of the classes deemed important by the developers.

In this paper, we present NavTracks, a tool that supports browsing through software. NavTracks keeps track of the navigation history of software developers, forming associations between related files. These associations are then used as the basis for recommending potentially related files as a developer navigates the software system. We present the reasoning behind NavTracks, its basic algorithm, a case study, and propose some future work. 1.

The maintenance, reengineering, and evolution of object-oriented software systems has become a vital matter in today’s software industry. Although most systems start off in a clean and well-designed state, with time they tend to gradually decay in quality, unless the systems are reengineered and adapted to the evolving requirements. However, before such legacy software systems can be reengineered and evolved, they must be reverse engineered, i.e., their structure and inner working must be understood. This is difficult because of several factors, such as the sheer size of the systems, their complexity, their domain specificity, and in general the bad state legacy software systems are in. In this thesis we propose a visual approach to the reverse engineering of object-oriented software systems by means of polymetric views, lightweight visualizations of software enriched with metrics and other types of semantic information about the software, e.g., its age, version, abstractness, location, structure, function, etc. We present and discuss several polymetric views which allow us to understand three different aspects of object-oriented software, namely 1. coarse-grained aspects which allow for the understanding of very large systems.

This paper describes a multi-perspective software visualization environment, SHriMP, which combines single view and multi-view techniques to support software exploration at both the architectural and source code levels. SHriMP provides three different views: a primary nested view and two subsidiary views. The primary nested view employs fisheye views of nested graphs, provides contextual cues, and supports general exploration activities. In SHriMP, subsidiary views exist as a searching tool and a relation tracer. These views complement each other and allow programmers to examine a software system from multiple perspectives.

Recently, many software visualization (SV) techniques and tools have become available. There is ample anecdotal evidence that appropriate visualization can significantly reduce the effort spent on system comprehension and maintenance, yet we are not aware of any quantitative investigation and survey of SV tools. This paper reports on a survey on SV tools which was conducted in spring 2000 with more than 100 participants. It addresses various functional, practical, cognitive as well as code analysis aspects that users may be looking for in SV tools. The participants of the survey rated the usefulness and importance of these aspects, and came up with aspects of their own. The participants were in general quite pleased with the SV tool they were using and mentioned various benefits. Nevertheless, a big gap between desired aspects and the features of current SV tools was identified. In addition, a list of improvements that should be done to current tools was assembled. Finally, the collected data tends to suggest that in general, code analysis aspects were not highly supported by the tools.

This paper describes a structured tool demonstration, a hybrid evaluation technique that combines elements from experiments, case studies, and technology demonstrations. Developers of program understanding tools were invited to bring their tools to a common location to participate in a scenario with a common subject system. Working simultaneously, the tool teams were given reverse engineering tasks and maintenance tasks to complete on an unfamiliar subject system. Observers were assigned to each team to find out how useful the observed program comprehension tool would be in an industrial setting. The demonstration was followed by a workshop panel where the development teams and the observers presented their results and findings from this experience.

Despite significant existing empirical work, little is known about the specific kinds of questions programmers ask when evolving a code base. Understanding precisely what information a programmer needs about the code base as they work is key to determining how to better support the activity of programming. The goal of this research is to provide an empirical foundation for tool design based on an exploration of what programmers need to understand about a code base and of how they use tools to discover that information. To this end, we undertook two qualitative studies of programmers performing change tasks to medium to large sized programs. One study involved newcomers working on assigned change tasks to a mediumsized code base. The other study involved industrial programmers working on their own change tasks to code with which they had experience. The focus of our analysis has been on what information a programmer needs to know about a code base while performing a change task and also on how they go about discovering that information. Based on a systematic analysis of the data from these user studies as well as an analysis of the support that current programming tools provide for these activities, this research makes four key contributions: (1) a catalog of 44 types of questions programmers ask, (2) a categorization of those questions into four categories based on the kind and scope of information needed to answer a question, (3) a description of important context for the process of answering questions, and (4) a description of support that is missing from current programming tools.