SFDL: MVC Applied to Workflow Design

Process management based on workflow systems is a growing trend in collaborative environments. One of the most notorious areas of improvement is that of user interfaces, especially since business process definition languages do not address efficiently the point of contact between workflow engines and human interactions. With that in focus, we propose the MVC pattern design to workflow systems. To accomplish this, we have designed a new dynamic view definition language called SFDL, oriented towards the easy interoperability with the different workflow definition languages, while maintaining enough flexibility to be represented in different formats and being adaptable to several environments. To validate our approach, we have carried out an implementation in a real banking scenario, which has provided continuous feedback and enabled us to refine the proposal. The work is fully based on widely accepted and used web standards (XML, YAML, JSON, Atom and REST). Some guidelines are given to facilitate the adoption of our solution

The pros and cons of using SDL for creation of distributed services

In a competitive market for the creation of complex distributed services, time to market, development cost, maintenance and flexibility are key issues. Optimizing the development process is very much a matter of optimizing the technologies used during service creation. This paper reports on the experience gained in the Service Creation projects SCREEN and TOSCA on use of the language SDL for efficient service creation

Experiments towards model-based testing using Plan 9: Labelled transition file systems, stacking file systems, on-the-fly coverage measuring

We report on experiments that we did on Plan 9/Inferno to gain more experience with the file-system-as-tool-interface approach. We reimplemented functionality that we earlier worked on in Unix, trying to use Plan 9 file system interfaces. The application domain for those experiments was model-based testing.\ud \ud The idea we wanted to experiment with consists of building small, reusable pieces of functionality which are then composed to achieve the intended functionality. In particular we want to experiment with the idea of 'stacking' file servers (fs) on top of each other, where the upper fs acts as a 'filter' on the data and structure provided by the lower fs.\ud \ud For this experiment we designed a file system interface (ltsfs) that gives fine-grained access to a labelled transition system, and made two implementations of it.\ud We developed a small fs that, when 'stacked' on top of the ltsfs, extends it with additional files, and an application that uses the resulting file system.\ud \ud The hope was that an interface like the one offered by ltsfs could be used as a general interface between (specification language specific) programs that give access to state spaces and (specification language independent) programs that use (walk) those state spaces like simulators, model checkers, or test derivation programs.\ud \ud Initial results (obtained on a less-than-modern machine) suggest that, although the approach by itself is definitely feasible in principle, in practice the fine-grained access offered by ltsfs may involve many file (9p) transactions which may seriously affect performance. In Unix we used a more conservative approach where the access was less fine-grained which likely explains why there we did not suffer from this problem.\ud \ud In addition we report on experiments to use acid to obtain coverage information that is updated on-the-fly while the program is running. This worked quite well. The main observation from those experiments is that the basic block notion of this approach, which has a more 'semantical' nature, differs from the more 'syntactical' nature of the basic block notion in Unix coverage measurement tools\ud like tcov or gcov

Initial thoughts on rapid prototyping techniques

This paper sets some context, raises issues, and provides our initial thinking on the characteristics of effective rapid prototyping techniques.After discussing the role rapid prototyping techniques can play in the software lifecycle, the paper looks at possible technical approaches including: heavily parameterized models, reusable software, rapid prototyping languages, prefabrication techniques for system generation, and reconfigurable test harnesses.The paper concludes that a multi-faceted approach to rapid prototyping techniques is needed if we are to address a broad range of applications successfully -- no single technical approach suffices for all potentially desirable applications

An overview of very high level software design methods

Very High Level design methods emphasize automatic transfer of requirements to formal design specifications, and/or may concentrate on automatic transformation of formal design specifications that include some semantic information of the system into machine executable form. Very high level design methods range from general domain independent methods to approaches implementable for specific applications or domains. Applying AI techniques, abstract programming methods, domain heuristics, software engineering tools, library-based programming and other methods different approaches for higher level software design are being developed. Though one finds that a given approach does not always fall exactly in any specific class, this paper provides a classification for very high level design methods including examples for each class. These methods are analyzed and compared based on their basic approaches, strengths and feasibility for future expansion toward automatic development of software systems

Working Notes from the 1992 AAAI Workshop on Automating Software Design. Theme: Domain Specific Software Design

The goal of this workshop is to identify different architectural approaches to building domain-specific software design systems and to explore issues unique to domain-specific (vs. general-purpose) software design. Some general issues that cut across the particular software design domain include: (1) knowledge representation, acquisition, and maintenance; (2) specialized software design techniques; and (3) user interaction and user interface