In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Computer Science

In this paper we evaluate logic code analysis and transformation frameworks for their suitability as basic infrastructures for fast detection and extraction of (crosscutting) concerns. Using design patterns as example concerns, we identify desirable properties that an infrastructure should fulfill. We then report our initial results of evaluating candidate systems with respect to these properties. We show how high precision design pattern detectors can be easily formulated as predicates that are evaluated in mere seconds even on the sources of large software systems, such as the Eclipse IDE. Although details still remain to be analyzed further, our current results suggest that the pair JTransformer & CTC is a good candidate for a general infrastructure, combining very good querying performance, scalability and short turnaround times with a seamless integration of querying and transformation capabilities.

Abstract. The Web Service Modelling Ontology (WSMO) provides a unique, highly innovative perspective onto the Semantic Web Services domain. Robust and easy-to-use tools play crucial role for the adoption of any technological innovation and indeed the overall value of the innovation can be severely undermined by the lack of proper tools supporting it. In this paper we present a prototype of an integrated modelling environment that supports and elaborates the innovative WSMO perspective. 1

Abstract—This paper describes work in progress to initiate the collaborative development of a new software platform for discrete-event simulation studies, the Open Simulation Architecture (OSA). OSA is primarily intended to be a federating platform for the simulation community: it is designed to favour the integration of new or existing contributions at every level of its architecture. The platform core supports discrete-event simulation engine(s) built on top of the ObjectWeb Consortium’s Fractal component model. In OSA, the systems to be simulated are modeled and instrumented using Fractal components. Fractal components offer many advanced and original features, such as multi-programming language support and the ability to share sub-components. In OSA, the event handling is mostly hidden in the controller part of the components, which alleviates noticeably the modeling process, but also ease the replacement of any part of the simulation engine. Apart the simulation engine, OSA aims at integrating useful tools for modeling, developing, experimenting and analysing simulations. For this purpose it relies on the Eclipse development platform and its ability to be extended. I.

Abstract. The Web Services Modelling Framework (WSMF) and the Web Services Modelling Ontology (WSMO) provide a unique, highly innovative perspective onto the Semantic Web and Web Services technologies. This paper introduces the WSMO Studio – a prototype that supports and elaborates this innovative perspective, making the technology easy to use and transparent for the end user. Our previous work on SWWS Studio has provided us with important experience and feedback, which we will reuse in our present work on WSMO Studio in order to provide a high quality integrated service environment for the Semantic Web Services domain. 1

This paper presents a new extension of the DEVS formalism that allows multiple occurrences of a given instance of a DEVS component. This paper is a follow-up to a previous short paper in which the issue of supporting a new construction called a shared component was raised, in the case of a DEVS model. In this paper, we first demonstrate, formally, that the multi-occurrence extended definition, that includes the case of shared components, is valid because any model that is built using this extended definition accepts an equivalent model built using standard DEVS. Then we recall the benefits of sharing components for modeling, and further extend this analysis to the simulation area, by investigating how shared components can help to design better simulation engines. Finally, we describe an existing implementation of a simulation software that fully supports this shared component feature, both at the modeling and simulation levels.

Humans have been observed to become disoriented when using menu or hypertext systems. Similar phenomena have been reported by software developers, often manifesting as a feeling of lostness while exploring a software system. To investigate this phenomena in the context of software development, we undertook a field study, observing eight developers of the open-source Eclipse project for two hours each as they conducted their normal development work. We also interviewed two other developers using the same tools but who were working on a closed-source system. The developers did report some instances of disorientation, but it was a rare occurrence; rather we observed strategies the developers used to remain oriented. Based on the study results, we hypothesize factors that contribute to disorientation during programming tasks as well as factors that contribute to remaining oriented. Our results can help encode best practices for code navigation, can help inform the development of tools, and can help in the further study of orientation and disorientation in software development. 1

The Web Services Modelling Framework (WSMF) and the Web Services Modelling Ontology (WSMO) provide a unique, highly innovative perspective onto the Semantic Web and Web Service technologies.

Over the past decade, since Java was first introduced and integrated into the Netscape web browser, several intermediate representations have been developed that might be potentially used for mobile code applications. This paper examines the requirements for a mobile code representation, presents several examples of stack-based, tree-oriented, and proof-annotating mobile code representations, and evaluates each of these representations according to the requirements. Povzetek: Članek podaja pregled mobilnih kod. 1

Omniscient debuggers make it possible to navigate backwards in time within a program execution trace, drastically improving the task of debugging complex applications. Still, they are mostly ignored in practice due to the challenges raised by the potentially huge size of the execution traces. This paper shows that omniscient debugging can be realistically realized through the use of different techniques addressing efficiency, scalability and usability. We present TOD, a portable Trace-Oriented Debugger for Java, which combines an efficient instrumentation for event generation, a specialized distributed database for scalable storage and efficient querying, support for partial traces in order to reduce the trace volume to relevant events, and innovative interface components for interactive trace navigation and analysis in the development environment. Provided a reasonable infrastructure, the performance of TOD allows a responsive debugging experience in the face of large programs.