Companies possess a history and large array of legacy information systems that consume a great part of their IT budget in operations and maintenance. These systems are mission-critical, and they cannot be fully discarded since they retain business rules and provide information that is not available anywhere else. Unfortunately, decades-old legacy systems cannot easily withstand modification. Mainframes specifically conglomerate most of these legacy systems. Although there are some white-box solutions for migrating mainframe systems, such solutions lack systematicity and do not provide mechanisms for verifying business rules preservation. Hence, this paper presents a black-box solution (ignoring the internal structure of COBOL programs) which uses a screen scraping technique for migrating mainframe systems toward JavaFX and relational databases. Together with this solution, this paper provides an automatic verification technique to check if the recreated system reflects all the embedded business logic. This proposal has been designed and developed in the context of an industrial project, in which the solution has already migrated 43,000,000 mainframe screens from four systems. The main implication for researchers and practitioners is that screen scraping has proved to be feasible for migrating mainframe systems in large-scale projects within a manageable time-frame while preserving business.

Due to their pivotal role in software engineering, considerable effort is spent on the quality assurance of software requirements specifications. As they are mainly described in natural language, relatively few means of automated quality assessment exist. However, we found that clone detection, a technique widely applied to source code, is promising to assess one important quality aspect in an automated way, namely redundancy that stems from copy&paste operations. This paper describes a large-scale case study that applied clone detection to 28 requirements specifications with a total of 8,667 pages. We report on the amount of redundancy found in real-world specifications, discuss its nature as well as its consequences and evaluate in how far existing code clone detection approaches can be applied to assess the quality of requirements specifications in practice.

Cloning in source code is a well known quality defect that negatively affects software maintenance. In contrast, little is known about cloning in requirements specifications. We present a study on cloning in 11 real-world requirements specifications comprising 2,500 pages. For specification clone detection, an existing code clone detection tool is adapted and its precision analyzed. The study shows that a considerable amount of cloning exists, although the large variation between specifications suggests that some authors manage to avoid cloning. Examples of frequent types of clones are given and the negative consequences of cloning, particularly the obliteration of commonalities and variations, are discussed.