Wednesday, Afternoon
Interconnecting Objects Via Contracts
Convention Ctr – 211D
Jose Luiz Fiadeiro, University of Lisbon
Luis Andrade, Oblog Software SA

Interactions between objects are too often coded in the way messages are exchanged and methods are called, making it difficult to understand and evolve the way components are interconnected without a deeper analysis of the way objects are designed. Yet, most businesses require high levels of reconfigurability of existing services, which suggests that an explicit model of the coordination that is required between system components should be given immediately during domain modeling.
Capitalizing on work in Software Architectures and Coordination Languages, and our experience in the banking industry, this tutorial puts forward the concept of contracts for providing explicit representations of interconnections between objects.

Attendees will be exposed to a new modeling primitive (contract) that has proved to be highly effective for controlling the complexity of system design and evolution. They will learn how to use it to externalize embedded coordination directives, ending-up with systems that can evolve simply by adding, removing, or replacing interconnections without having to change the other components. Because the concept is intrinsically language-independent, and an implementation pattern is provided, attendees will be able to put it to practice immediately in their working environments.

Presentation Format: 50% lecture + 50% group exercises.

Attendee Background: Familiarity with object-oriented conceptual modeling

José Luiz Fiadeiro is Professor of Computing Science at the University of Lisbon. His research interests include software specification formalisms and methods, especially as applied to component-based, reactive systems, and their integration in the wider area of General Systems Theory. His main contributions have been in the formalization of specification and program design techniques and of their underlying modularization principles, namely in connection to Software Architectures. These research interests have been pursued in the context of several national and international projects. He has published more than 70 papers in these areas, including the foundations of object-oriented systems.

Luís Filipe Andrade is partner and Technical Vice-President of Oblog SA ( in Portugal and Oblog Technology Inc. in the USA – an Information Technology Company owned by one of the most important Portuguese financial groups (“Espírito Santo”). This company has developed, under his coordination, a sophisticated object-oriented specification language (OBLOG) and its supporting tools. He is also partner and president of a software company that develops banking applications and tools based on the OBLOG language, and has extensive experience in projects implementing transactional systems to support the front-end transactions of bank branches. Previously, he had been Information Technology Manager in the biggest Portuguese financial group - CGD - and senior researcher at INESC, an institute for System and Computer Engineering where he led a research project in specification models, compilers, and code generators that later became a commercial product.

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