Author(s): Piriquito, Maria Margarida Lameira da Cunha
Date: 2009
Persistent ID: http://hdl.handle.net/10362/2015
Origin: Repositório Institucional da UNL
Subject(s): Component orientation; Type systems; Dynamic reconfiguration; Subtyping; Type inference
Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para a obtenção do grau de Mestre em Engenharia Informática.
With the constant evolution of software systems need arises for more structured implementations, where processes like software updates and changes in systems can be easily made, with no need to change what had previously been implemented. One possible solution to this problem is the use of component-based programming languages. This kind of programming languages tries to promote not only code reuse but also a black-box discipline where it is not needed how a service is implemented, but only its interface so that it can be used. The ComponentJ programming language seeks to provide a simple way to perform component creation and composition, making this new programming paradigm somewhat easy to use. Because ComponentJ is meant to be an extension to the Java programming language it becomes possible to implement components using the whole expressiveness of this language. It is also possible, in ComponentJ, to dynamically change components and the object structure based on runtime decisions. This dynamic reconfiguration process allows, for instance, to perform changes/updates to a certain software system without having to stop its execution. The goal for this project is to implement a type system for the ComponentJ programming language, based on the work presented in [32, 28]. Type verification is syntax driven, and uses structural equivalence of types. Advanced techniques such as subtyping and type inference are also included in order to make the language more flexible. Besides the static type checker, a dynamic checker is also included, allowing the type safe application of runtime changes to the system (dynamic reconfiguration of objects) before their application.
