The Simple Concurrent Object-Oriented Programming (SCOOP) mechanism introduces inter-object concurrency to the Eiffel language, via addition of one new keyword, separate. We describe a general tool that takes a Eiffel program that makes use of SCOOP and separate, and translates it into an Eiffel

Reliability is even more important in object-oriented programming than elsewhere. This article shows how to reduce bugs by building software components on the basis of carefully designed contracts. 40 s object-oriented techniques steadily gain ground in the world of software development. users and prospective users of these techniques are clam-oring more and more loudly for a “methodology ” of object-oriented software construction- or at least for some methodological guidelines. This article presents such guidelines, whose main goal is to help improve the reliability

Pfam is a comprehensive collection of protein domains and families, represented as multiple sequence alignments and as profile hidden Markov models. The current release of Pfam (22.0) contains 9318 protein families. Pfam is now based not only on the UniProtKB sequence database, but also on NCBI GenPept and on sequences from selected metage-nomics projects. Pfam is available on the web from the consortium members using a new, consistent and improved website design in the UK

Object-oriented languages were invented to provide an intuitive view of data and computation, by drawing an analogy between software and the physical world of objects. The detailed explanation of this intuition, however, turned out to be quite complex; there are still no standard definitions of such fundamental notions as objects, classes, and inheritance. Much progress was made by investigating the notion of subtyping within procedural languages and their theoretical models (lambda calculi). These studies clarified the role of subtyping in object-oriented languages, but still relied on complex encodings to model object-oriented features. Recently, in joint work with Martin Abadi, I have studied more direct models of object-oriented features: object calculi. Object calculi embody, in a minimal setting, the object-oriented model of computation, as opposed to the imperative, functional, and process models. Object calculi are based exclusively on objects and methods, not on functions or data structures. They help in classifying and explaining the features of object-oriented languages, and in designing new, more regular languages. They directly inspired my design of Obliq, an object-oriented language for network programming.

The C programming language was devised in the early 1970s as a system implementation language for the nascent Unix operating system. Derived from the typeless language BCPL, it evolved a type structure; created on a tiny machine as a tool to improve a meager programming environment, it has become one of the dominant languages of today. This paper studies its evolution.

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A federated database system (FDBS) is a collection of cooperating database systems that are autonomous and possibly heterogeneous. In this paper, we define a reference architecture for distributed database management systems from system and schema viewpoints and show how various FDBS architectures can be developed. We then define a methodology for developing one of the popular architectures of an FDBS. Finally, we discuss critical issues related to developing and operating an FDBS.

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This thesis defines a set of program restructuring operations (refactorings) that support the design, evolution and reuse of object-oriented application frameworks. The focus of the thesis is on automating the refactorings in a way that preserves the behavior of a program. The refactorings are defined to be behavior preserving, provided that their preconditions are met. Most of the refactorings are simple to implement and it is almost trivial to show that they are behavior preserving. However, for a few refactorings, one or more of their preconditions are in general undecidable. Fortunately, for some cases it can be determined whether these refactorings can be applied safely. Three of the most complex refactorings are defined in detail: generalizing the inheritance hierarchy, specializing the inheritance hierarchy and using aggregations to model the relationships among classes. These operations are decomposed into more primitive parts, and the power of these operations is discussed from the perspectives of automatability and usefulness in supporting design. Two design constraints needed in refactoring are class invariants and exclusive components. These constraints are needed to ensure that behavior is preserved across some refactorings. This thesis gives some conservative algorithms for determining whether a program satisfies these constraints, and describes how to use this design information to refactor a program.