Tutorials -- Half Day/Tuesday PM

Even if mechanisms are provided for capturing and integrating behavioral aspects in system models, object-oriented approaches have not yet produced primitives and constructs for treating interactions as first-class citizens. Interactions between objects in a system are too often coded in the way messages are exchanged and methods are called, making it difficult to understand and evolve the discipline that governs the interaction between different components of a system without a deeper analysis of the way objects are designed. Yet many application domains, like banking, require high levels of reconfigurability of existing services, e.g. new ways for clients to interact with their bank accounts. This suggests that an explicit model of the coordination that is required between the different components in the system should be given immediately at the level of the domain model.

This tutorial puts forward the concept of contract as a mechanism for providing explicit representations of interconnections between objects. The usefulness of the concept is illustrated with examples taken from real-life projects. Finally, we show how contracts can be realised both in UML-like languages and ORBs.

Attendee Background: Familiarity with object-oriented conceptual modeling and architectural design is useful.

Luís Andrade is partner and Technical Vice-President of Oblog SA in Portugal and Oblog Technology Inc. in the USA This company has developed a sophisticated object-oriented specification language (OBLOG) and its supporting tools. He is also partner and president of a software company with extensive experience in developing banking applications and tools based on the Oblog language.

José Fiadeiro is Professor for Computing Science at the University of Lisbon. 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. He has published more than 70 papers in these areas. He has also co-authored and presented a tutorial on the formalization of object-oriented modeling techniques at OOPSLA'94.