TARA: Tool Assisted Requirements Analysis

Requirements analysis is one of the most critical and difficult tasks in software engineering. The need for tool support is easily justified. This paper describes an approach to the provision of such support for three particular aspects method support by active guidance, validation by transaction anomation, and reuse of specification fragments. Method guidance is supported by a method model used to describe the sequence of method steps that should be followed. This model is directly interpreted by the tools to provide advice and reasoning. It is used in conjunction with rules used for consistency checking to provide remedial advice. The animator provides facilities for the selection and execution of a transaction to reflect the specified behavior given a particular scenario. Actions are described in terms of input-out relations. Simple rules can be specified to control the execution of actions. Facilities are provided to replay and interact with transactions. Reuse is supported by facilities for identifying candidate transactions from a reuse database. The search strategies provided include browsing in an inheritance structure, different levels of pattern matching, casual chain matching matching of the underlying control structures, and purpose matching. Support is then provided for the allocation of the selected fragment to the target environment. The approach has been tested by implementing a prototype set of tools for the CORE method and the Analyst workstation. A major case study, the ASE Advanced Sensor Exploitation test environment, has been analyzed and specified using CORE, the Analyst, and the tools described above. The results of that work are described and evaluated.