Claire Knight

Virtual but visible software

The problem of trying to view and comprehend large amounts of data is a well-known one. A specialised version of this problem, that of visualising program code (often known as software visualisation) has suffered from the field refusing to embrace new ideas and technologies. The paper presents an application of virtual reality to this problem and highlights areas of importance from virtual reality that have been used to good effect when creating graphical abstractions of Java source code. A summary of the achievements of this approach and the relationship to the virtual reality features believed to be most beneficial is provided.

Comprehension with[in] virtual environment visualisations

For many years, basic visualisation based around simple boxes and lines, has been done in an attempt to be able to ease some of the cognitive overload caused by program comprehension. The problems with such visualisations is that they can very easily become incomprehensible by trying to force large amounts of information into a small space, relying solely on two dimensions for the representations. Three-dimensional visualisations are one approach that is being considered to combat these problems, although there are also many different issues that must be considered for these sorts of visualisations. Especially when those visualisations are of intangible software systems. A solution is to use virtual environments as a base for these three-dimensional visualisations, which allows a sense of context to be maintained and also promotes collaboration between the people trying to comprehend the code.

Visualisation for informed decision making; from code to components

The problem of trying to view and comprehend large amounts of data is a well-known one. A specialised variant of this problem is the visualisation of software code and components for the purposes of understanding, decision-making, reuse and even integration. In particular the visualisation of software components, at a much higher level than source code, has received very little research. Visualisation is a powerful tool in situations such as this. This paper presents the application of real world metaphor based visualisations that address this problem. The application of visualisation to selecting software components is especially novel. It seeks to decrease the effort required by system integrators when locating suitable components in what is an increasingly crowded marketplace. Accurate information and understanding are vital if correct and informed decisions and judgements are to be made.

Mediating diverse visualisations for comprehension

For ease of use, comprehension, and general acceptability it is important that tools that purport to aid comprehension are able to provide a variety of customisable views. The most important underlying factor is the wide differences between users in terms of their culture, experience, visual together, working preferences, and general abilities. Comprehension studies have also shown that different views, and the ability to selectively filter data are important. Combining all of these ideals into one, automated infrastructure is the focus of this paper. Component technologies provide a way of making this a reality, and also for providing visualisation creators with a general application into which they can leverage their work. Advances in this arena have allowed for component brokerage and automatic dynamic data connections to become an actuality.

Program comprehension experiences with GXL; comprehension for comprehension

Tools are vital to support the various activities that form the many tasks that are part of the program comprehension process. In order for these tools to be used and useful, it is necessary that they support the activities of the user. This support must complement the work methods and activities of the user and not hinder them. Whilst features of good tools have been identified, tool builders do not always adhere to them. It is important to consider whether needs have changed, and if those desirable properties need augmenting or revising. From experience of maintaining and enhancing an existing program comprehension tool for the purposes of participating in a re-engineering activity, many lessons on tool support have been learned. Various program comprehension strategies are introduced in this paper. The use of GXL (Graph eXchange Language) and involvement in the SORTIE project are presented with reference to the tool being adapted and used. Details of the changes made are given to illustrate the support desired. These all feed into the final section of the paper that discusses the sort of support that tools should provide, current tool deficiencies and some of the ways in which these could be addressed.

Smell the coffee! Uncovering Java analysis issues

The article sets out to address some of the issues that occur when there is a need to utilise analysis and manipulation techniques on Java source code. Unfortunately, Java has been largely ignored within academia with more interest still being expressed in COBOL, C, and C++. This is a problem because of the utilisation of Java in industry and the need to be able to analyse and comprehend systems that are already in existence. Java programs have the same problems as with those written in other languages; but there are also some that are more related to Java and the object-oriented paradigm, and also to the newer initiatives that Java is now involved with. The paper presents a survey of these issues and seeks to stimulate discussion and possible solutions for them.

Should users inhabit visualisations

The use of three-dimensions for visualisation is a lot newer than the technology required to achieve such visual representations. A further extension of this work is to add multiple users to one visualisation environment to create visualisations that go beyond individual intelligence amplification and become knowledge repositories, shared workspaces and integral parts of the management of the data which they represent. The issues surrounding such uses of visualisations are presented in this paper, with an extension of a three-dimensional visualisation to encompass these ideas.

Organisational trails through software systems

The use of three dimensional software visualisation techniques has the power to transform the way that tacit knowledge gathering and retrieval takes place during many software maintenance activities. The focus of this work is the understanding and management of software from various perspectives and therefore it is the visualisation of these software artefacts that is of greatest interest. This work moves towards providing a generic visualisation that is applicable to the management of many software systems within the bounds of the organisation, with the ability to view various artefacts over time (and thus their evolution) and also to incorporate lower level visualisations in three dimensions.

Visualisations; Functionality and Interaction

The interface to any visualisation application can essentially be split into two; the visualisation itself, and the interface that is associated with the interface. Despite the fact that the data plays a major part in any visualisation application, this is generally accessed only through either the interface or the visualisation. An important issue then arises over the location of functionality in the application. To be able to provide a usable and effective visualisation application (including data integration) where are the various selections, filters, customisations, and interrogation mechanisms located; the visualisation or the interface? The interaction mechanisms involved play a part in guiding this decision, but the amount of coupling between the visualisation and interface is also important.

Service-oriented visualizations

It is important to be able to provide a variety of ways of visualising any data set if the differences between users in terms of ability and preferences are to be successfully overcome. Human variability is a wonderful thing; except perhaps when there is a visualisation being evaluated! There is not likely to be a representation that fulfils the needs of any given group of users and still remains likeable to them all. This provided the impetus to create a visualisation framework that is able to a variety of visualisations and data through a service mechanism. This allows for matching services to be located, and utilised, as necessary, using a contain clie3nt application that acts to hold the component parts of the framework together. This provides representations each user is happiest with to be employed (of those made available), and also for a comprehensive analysis and understanding tool because of the multiple sources of data that can be integrated. In order to best exploit the possible distributed nature of visualisations and data sources, and to provide extensibility for collaboration and Grid integration the implementation make use of Jini.