Carl Cook

An extensible framework for collaborative software engineering

The size, complexity and duration of typical software engineering projects means that teams of developers will work on them. However, with the exception of version control systems, the editors, diagrammers and other tools used will generally support only a single user. We present an architecture for bringing to software engineering development environments the advantages of awareness of the presence, intentions, and actions of others. Thus far, the applications of such facilities have been primarily in simple computer supported cooperative work (CSCW) tools, such as shared whiteboards, where the corresponding artifacts, unlike those of software engineering, are typically both simple and transient. We describe our implementation of the architecture and prototype tools and illustrate the benefits of providing support for real-time collaboration between developers located anywhere on the Internet. We also describe how our architecture, which is based on a parse tree representation of artifacts, may be extended readily to include new tools, languages, and notations or be customised to provide new awareness mechanisms.

A user evaluation of synchronous collaborative software engineering tools

Collaborative software engineering (CSE) is a rapidly growing field. Tools such as IDEs are now beginning to incorporate new collaborative features. We have developed several real-time CSE tools which support fine-grained collaboration. In this paper we present an empirical evaluation to investigate the potential benefits of our tools for collaborative source code development. Our results show that for the two typical types of collaborative programming scenarios studied, users of CSE tools achieve task completion rates at least twice as fast as those obtained from their single-user counterparts. Additionally, participants indicated strong support for the concept of CSE tools. These results encourage us to continue developing our CSE tools, and to investigate their use in other software engineering contexts.

Parsing and semantic modelling for software engineering applications

The ability to parse source code, in order to extract information from it, is an essential element of software engineering research and practice. However, serious practical difficulties often arise from factors such as ambiguities in standard grammars and inflexible parsing tools. For example, substantial changes to standard grammars may be needed in order to meet the limitations of parsing engines; this threatens the accuracy, completeness and consistency of the information available. Good parsing on its own is not enough: an inadequate semantic model limits the information available to tool builders. In our work, we have developed an approach to parsing and semantic modelling which addresses issues such as these. Our approach is based on a more flexible LR parser generator which includes the use of generalised LR (GLR) parsing to accommodate ambiguous grammars. This allows us to decouple syntactic and semantic analysis. In this paper, we present our parser generator, yakyacc, and our semantic model for Java, JST, and discuss the benefits of their use in software engineering research. The resulting parsers may be used in a variety of contexts, either as the basis for integrated applications or as components in an application pipeline containing a number of other tools. We illustrate the benefits of our approach with representative examples from two of our current software engineering research projects.

COMAN: a multiple-language active network architecture enabled via middleware

In conventional data communication networks, the basic network components are passive, where routing decisions are made solely on the basis of packet header information. In contrast, active networks allow added computation within the network through user-defined routing and processing instructions, providing the on-demand installation of powerful software-based network services. As an adaptation of previous active networks, this paper introduces an architecture based entirely in middleware. By utilizing middleware services, the architecture resolves authentication, memory-management, and interconnectivity issues otherwise assumed as inherent, and enables a highly functional multiple-language interface for the deployment of dynamic protocols. After describing the architectural design, an empirical system evaluation is presented with comparisons to both conventional network protocols, and a wellknown existing active network architecture. Results indicate performance improvements over the existing architecture, and demonstrate the feasibility of a multiple-language active network infrastructure implemented entirely in middleware.