UML Deficiencies from the perspective of Automatic Performance Model Generation

A discussion surrounding the use of UML for distributed system design

An 00 visual language definition approach supporting multiple views

The formal approach to visual language definition is to use graph grammars and/or graph transformation techniques. These techniques focus on specifying the syntax and manipulation rules of the concrete representation. This paper presents a constraint and object-oriented approach to defining visual languages that uses UML and OCL as a definition language. Visual language definitions specify a mapping between concrete and abstract models of possible visual sentences, which carl subsequently be used to determine if instances of each model "validly" express each other. This technique supports many:many mappings between concrete and abstract model instances, and supports the implementation of functionality that requires feedback from the abstract domain to the concrete

Communications software performance prediction

Software development can be costly and it is important that confidence in a software system be established as early as possible in the design process. Where the software supports communication services, it is essential that the resultant system will operate within certain performance constraints (e.g. response time). This paper gives an overview of work in progress on a collaborative project sponsored by BT which aims to offer performance predictions at an early stage in the software design process. The Permabase architecture enables object-oriented software designs to be combined with descriptions of the network configuration and workload as a basis for the input to a simulation model which can predict aspects of the performance of the system. The prototype implementation of the architecture uses a combination of linked design and simulation tools

Validating BPEL Specifications using OCL

This report gives a UML model of the structure for a BPEL document and provides a formal version of each informal constraint using the Object Constraint Language (OCL). Given this formalisation of the constraints, it is possible, using tools developed at Kent along with IBMs Eclipse Modelling Framework (EMF) to convert the OCL constraints into Java code that forms an automatic validation tool for BPEL documents

Relations in OCL

OCL is proposed as a query language within the QVT framework. The main QVT submission bases the specification of transformations on the concept of relations. Relations are not first class entities within the OCL. By extending OCL with the concept of Relations it can better serve the needs of the QVT framework. In particular this enables OCL to be used as a semantic interpretation of a QVT transformation language and may even facilitate the use of OCL as a transformation specification language

Proposal for a Model Driven Approach to Creating a Tool to Support the RM-ODP

The potential for revising the RM-ODP standards is an excellent opportunity to move the given specifications into a form that is more amenable to the provision of tools that support the standard. Adoption of the approach advocated by the RM-ODP would be greatly increased if tools to support the approach were more readily available. This paper proposes an approach to generating such tools, directly, from a model based approach to specifying the RM-ODP viewpoint languages and correspondences. In particular this paper highlights certain requirements that the specification approach would need to meet if the production of such tools were to be achievable

MDA-Transformations from Relations

The Model Driven Architecture (MDA) is an approach to IT systems development fostered by the Object Management Group (OMG). It is based on forming a separation between the specification of a systems essential functionality as a platform independent model (PIM) and the realisation of the system using more detailed and specific platform specification (PSM). It is recognised that specifying the mappings or transformations from PIM to PSM is a key enabling aspect of the MDA approach. Currently the OMG's Request for Proposals (RFP) on techniques and facilities to enable transformations is in progress. In this position paper we discus a technique for specifying transformations that is based on the mathematical foundation of relations. Using these relation specifications we show how the additional definition of some build expressions enables the generation of a transformation engine that will map model instances from either side of the specification to the other. This approach has been proved to work on a number of small case studies, using the KMF code generation tools to build transformation engines from specifications

UML specification of distributed system environments

The specification of distributed systems is a complex task, which is made easier by the use of object-oriented design methodologies. With the advent of UML as a standard notation for object-oriented software design, the application of this notation to the design of distributed systems is appropriate. The design of distributed systems involves both software and hardware specifications, however, the UML notation is primarily directed at the design of the software within a system and the facilities directed towards the specification of the physical environment are limited. Specification of the physical environment using UML can be achieved, but by using alternative parts of the notation to the proposed implementation diagrams. Using the alternatives presented in this paper enables a satisfactory specification, which is for example, detailed enough for the automatic generation of performance models