Software maintenance: redocumentation of existing Cobol systems using hypertext technology

One of the major problems associated with the maintenance of existing software systems is their lack of documentation. This can make very large, poorly structured programs very difficult to maintain. Nearly all traditional documentation tools are either designed for use in the development stage of the software lifecycle or are report generators such as cross reference generators. The problems of lack of documentation are compounded when applied to third party software maintenance as the staffs are often initially unfamiliar with the code they are maintaining. This thesis describes these problems in detail and evaluates the feasibility of a tool to help with redocumentation based on current hypertext technology

Measurement for the management of software maintenance

This thesis addresses the problem of bringing maintenance, in a commercial environment, under management control, and also increasing the profile of maintenance in a corporate picture, bringing it onto a par with other components of the business. This management control will help reduce costs and also the time scales inherent in maintenance activity. This objective is achieved by showing how the measurement of the products and processes involved in maintenance activity, at a team level, increases the visibility of the tasks being tackled. This increase in visibility provides the ability to impose control on the products and processes and provides the basis for prediction and estimation of future states of a project and the future requirements of the team. This is the foundation of good management. Measurement also provides an increase in visibility for higher management of the company, forming a basis for communication within the corporate strategy, allowing maintenance to be seen as it is, and furnished with the resources it requires. A method for the introduction of a measurement strategy, and collection system, is presented, supported by the examination of a database of maintenance information collected by a British Telecom research team, during a commercial software maintenance exercise. A prototype system for the collection of software change information is also presented, demonstrating the application of the method, along with the results of its development and the implications for both software maintenance management and the technical tasks of implementing change

End-user documentation

The first and most basic problem with documentation is that the consumer of software applications does not want to use the documentation included with a software product for one or more reasons. Studies, and papers, have been done on the effect that documentation has on a user's satisfaction with a software application; its ease of use, how quickly a user can learn to use the application, and on how documentation should be standardized. The premise of this thesis is that an improvement to the software maintenance processes can be achieved by limiting maintenance requests to "actual” problems with software, versus "perceived" problems caused by inadequate end-user documentation. After analyzing the literature within the computer science communities on the software maintenance process, and the literature within the educational and psychological communities on learning, retention, and the effect of software documentation on the end-user, a modification to the Foster Model was conceived. This model incorporates the concept of an Interactive Documentation Program (IDP), which allows for the end-user to utilize end-user directed and task-based documentation to improve their skills with the operation of commercially available off-the-shelf "office application" software as well as in-house developed software of a similar nature. To ascertain the viability of this concept, a world-wide survey of end-users is concerning their needs, desires, expectations, and complaints concerning end-user documentation was conducted. Combining the statistical results of the analysis of this survey with the concept of the IDP resulted in a new visuaUy-based and task oriented documentation paradigm called hypervideo

Virtual software in reality

Software visualisation is an important weapon in the program comprehension armoury. It is a technique that can, when designed and used effectively, aid in understanding existing program code. It can achieve this by displaying information in new and different forms, which may make obvious something missed in reading the code. It can also be used to present many aspects of the data at once. Software, despite many software engineering advances in requirements, design and implementation techniques, continues to be complex and large and if anything seems to be growing in these respects. This means that techniques that failed to aid comprehension and maintenance are certainly not going to be able to deal with the current software. Therefore this area requires research to be able to suggest solutions to deal with the information overload that is sure to occur. There are several issues that this thesis addresses; all of them related to the creation of software visualisation systems that are capable of being used and useful well into the next generation of software systems. The scale and complexity of software are pressing issues, as is the associated information overload problem that this brings. In an attempt to address this problem the following are considered to be important: abstractions, representations, mappings, metaphors, and visualisations. These areas are interrelated and the first four enable the final one, visualisations. These problems are not the only ones that face software visualisation systems. There are many that are based on the general theory of the applicability of the technique to such tasks as program comprehension, rather than the detail of how a particular code fragment is shown. These problems are also related to the enabling technology of three- dimensional visualisations; virtual reality. In summary the areas of interest are: automation, evolution, scalability, navigation and interaction, correlation, and visual complexity. This thesis provides an exploration of these identified areas in the context of software visualisation. Relationships that describe, and distinguish between, existing and future software visualisations are presented, with examples based on recent software visualisation research. Two real world metaphors (and their associated mappings and representations) are defined for the purpose of visualising software as an aid to program comprehension. These metaphors also provide a vehicle for the exploration of the areas identified above. Finally, an evaluation of the visualisations is presented using a framework developed for the comparative evaluation of three-dimensional, comprehension oriented, software visualisations. This thesis has shown the viability of using three-dimensional software visualisations. The important issues of automation, evolution, scalability, and navigation have been presented and discussed, and their relationship to real world metaphors examined. This has been done in conjunction with an investigation into the use of such real world metaphors for software visualisation. The thesis as a whole has provided an important examination of many of the issues related to these types of visualisation in the context of software and is therefore a valuable basis for future work in this area

Inverse software configuration management

Software systems are playing an increasingly important role in almost every aspect of today’s society such that they impact on our businesses, industry, leisure, health and safety. Many of these systems are extremely large and complex and depend upon the correct interaction of many hundreds or even thousands of heterogeneous components. Commensurate with this increased reliance on software is the need for high quality products that meet customer expectations, perform reliably and which can be cost-effectively and safely maintained. Techniques such as software configuration management have proved to be invaluable during the development process to ensure that this is the case. However, there are a very large number of legacy systems which were not developed under controlled conditions, but which still, need to be maintained due to the heavy investment incorporated within them. Such systems are characterised by extremely high program comprehension overheads and the probability that new errors will be introduced during the maintenance process often with serious consequences. To address the issues concerning maintenance of legacy systems this thesis has defined and developed a new process and associated maintenance model, Inverse Software Configuration Management (ISCM). This model centres on a layered approach to the program comprehension process through the definition of a number of software configuration abstractions. This information together with the set of rules for reclaiming the information is stored within an Extensible System Information Base (ESIB) via, die definition of a Programming-in-the- Environment (PITE) language, the Inverse Configuration Description Language (ICDL). In order to assist the application of the ISCM process across a wide range of software applications and system architectures, die PISCES (Proforma Identification Scheme for Configurations of Existing Systems) method has been developed as a series of defined procedures and guidelines. To underpin the method and to offer a user-friendly interface to the process a series of templates, the Proforma Increasing Complexity Series (PICS) has been developed. To enable the useful employment of these techniques on large-scale systems, the subject of automation has been addressed through the development of a flexible meta-CASE environment, the PISCES M4 (MultiMedia Maintenance Manager) system. Of particular interest within this environment is the provision of a multimedia user interface (MUI) to die maintenance process. As a means of evaluating the PISCES method and to provide feedback into die ISCM process a number of practical applications have been modelled. In summary, this research has considered a number of concepts some of which are innovative in themselves, others of which are used in an innovative manner. In combination these concepts may be considered to considerably advance the knowledge and understanding of die comprehension process during the maintenance of legacy software systems. A number of publications have already resulted from the research and several more are in preparation. Additionally a number of areas for further study have been identified some of which are already underway as funded research and development projects