Automatic Extraction of Structural Model from Semi Structured Software Requirement Specification

The software requirement specifications are usually documented either in unstructured, semi structured or structured format. The requirements specified in unstructured format are written in simple continuous paragraph and the structured format specifies requirements by means of diagrams. The semi-structured format represents requirements with the help of some keywords. Literature suggests that the rule based work has been the common choice for unstructured format of documenting. However, these rule based works do not yield satisfactory results for semi-structured format. Consequently, these rules need to re-framed in order to apply them for the semi-structured formatted documents. In this paper, we present an improvement on the existing rules considering the keywords present in the text. The technique involves automatic extraction of the class diagrams using NLP tools and techniques. Along with existing rules, the newly formulated rules have been tested for different case studies and suitable metrics have been devised to evaluate the obtained results. Results show that the automatically generated class diagram have 82% average precision value and 94% average recall value when compared to the class diagrams generated by the human experts.