Separating the specification and implementation phases in cryptology

COSINE Implementation Phase: COSINE project officer's view

The existence of mechanisms to describe and evaluate assertions in programming languages helps to reduce the conceptual gap existing between the specification and implementation phases in the software development, improving both tasks. Java, originally used as an Internet-oriented implementation language, is becoming a general-purpose language, which unfortunately does not provide this kind of mechanism. We present a proposal to include assertions into Java, which also allows including the use of quantified variables in the assertions. The paper analyzes the properties that such integration must satisfy in order to guarantee a seamless interaction with the rest of the language constructions. The proposal shows how assertions can be used to synchronize Java threads introducing the notion of synchronization object and extending the semantics of preconditions. The goal is to increase the object oriented expressiveness of the language to describe concurrency.

This paper introduces graphical user interface (GUI) modelling approach and it positions in information system (IS) development process. The overview of graphical user interface design methods and methodologies is presented. The main objective of the proposal is the consistency of IS development process, which includes requirements specification, system design and implementation phases. The GUI modelling process is based on the data flows specification. Detailed explanation of modelling steps is presented. Paper includes an illustrative example of the web based GUI development according to the proposed process.

Specifications are important in software development because a large percentage of the errors at implementation and test phases are traceable to a lack of precision of the specifications. Formal methods are studied and applied to produce clear specifications and argue about them rigorously. As formal methods may even increase the ratio of specification phase in the software life-cycle, it is necessary to be efficient in debugging, modification, and reuse of specifications to reduce cost of the whole software development process. In a large scale specification in particular, parts extracted from the specification are useful. We introduce here a specification slicing that supports debugging, modification and reuse of specifications. In this paper, we define specification slice as a part of a specification that defines or restricts values of a particular variable used in the specification. Attention is also directed to applications of specification slicing and support tools. >