Feature level metrics based on size and similarity in software product line adoption

Introducing software product lines is a natural way to cope with a large number of software variants and hard maintenance. This task can become more complicated with a fourth generation language, namely Magic in our case. Feature extraction is an important task of product line adoption, and the extracted features can amount to large proportions of the code and can be hard to contemplate, thus appropriate methods become necessary to ease the handling of the information gained. In this work we present some feature level metrics aiming to highlight valuable information on both the results attained through extraction and the features themselves which can be used in furthering the process of product line adoption. We present some metrics based on size and pairwise similarity of the features of four different variants of the same system. The knowledge of these metrics, properly measured and used can be vital in aiding product line adoption

A Syntactical Reverse Engineering Approach to Fourth Generation Programming Languages Using Formal Methods

Fourth-generation programming languages (4GLs) feature rapid development with minimum configuration required by developers. However, 4GLs can suffer from limitations such as high maintenance cost and legacy software practices. Reverse engineering an existing large legacy 4GL system into a currently maintainable programming language can be a cheaper and more effective solution than rewriting from scratch. Tools do not exist so far, for reverse engineering proprietary XML-like and model-driven 4GLs where the full language specification is not in the public domain. This research has developed a novel method of reverse engineering some of the syntax of such 4GLs (with Uniface as an exemplar) derived from a particular system, with a view to providing a reliable method to translate/transpile that system's code and data structures into a modern object-oriented language (such as C\#). The method was also applied, although only to a limited extent, to some other 4GLs, Informix and Apex, to show that it was in principle more broadly applicable. A novel testing method that the syntax had been successfully translated was provided using 'abstract syntax trees'. The novel method took manually crafted grammar rules, together with Encapsulated Document Object Model based data from the source language and then used parsers to produce syntactically valid and equivalent code in the target/output language. This proof of concept research has provided a methodology plus sample code to automate part of the process. The methodology comprised a set of manual or semi-automated steps. Further automation is left for future research. In principle, the author's method could be extended to allow the reverse engineering recovery of the syntax of systems developed in other proprietary 4GLs. This would reduce time and cost for the ongoing maintenance of such systems by enabling their software engineers to work using modern object-oriented languages, methodologies, tools and techniques

Automated Reverse Engineering of Legacy 4GL Information System Applications using the ITOC Workbench

. Most contemporary fourth-generation languages (4GLs) are tightly coupled with the relational database and other subsystems provided by the vendor. As a result, organisations wishing to change database vendors are typically forced to rewrite their applications using the new vendor's 4GL. The anticipated cost of this redevelopment can deter an organisation from changing vendors, hence denying it the benefits that would otherwise result, for example, the exploitation of more sophisticated database technology. If tools existed that could reduce the rewriting effort, the option of changing database vendors would become more economically feasible. The ITOC project is a large collaborative research initiative between the Centre for Software Maintenance at the University of Queensland and Oracle Corporation. The primary goal of the project is to develop tools to assist in the migration of 4GL information system applications. A tool resulting from the project has been utilised to recover des..