An Ontology Based Test Case Generation Framework

Abstract

Abstract Software testing is a crucial part of the software development life cycle which ensures that the developed product meets the user requirements. Currently, test cases which come under the test design phase are written almost manually based on user requirements in the companies who follow Agile methodology. This tedious manual process requires 40-70% of the software test life cycle which has affected on cost, time and effort factors due to the frequent changes in requirements and having different terminologies. Companies that follow Agile practices along with Behaviour Driven Development approach capture requirements through user stories written in natural language. Representation of requirements in a formalized way affect the high effectiveness of requirement management by reducing the time and cost factors. Ontology is such an approach where it leads to knowledge reuse for sharing common terminologies and concepts by modelling the requirement domain knowledge constructed with the reasoning behaviour. To achieve automated test case generation, an Ontology-based system has been developed with the purpose of maximising semantic technology representation for the requirement domain. Instead of writing test cases manually, this thesis investigates a practical solution for automatically generating test cases within an Agile software development using natural language-based user stories with an Ontology-based approach for requirement representation. To establish the feasibility, a framework has been developed that uses NLP techniques which can auto-generate functional positive test cases from the requirements provided through user stories, based on that developed Ontology. The use of an Ontology knowledge base for the software requirement domain has given a better manageability of the requirement domain while the framework reduces the effort required to create the test cases. Also the thesis has introduced a new concept as an Ontologist role into the software development process for the evolvement of the Ontology model. Results from the system evaluation and user evaluation are presented in this thesis. Comparing these results with the test cases taken from the industry which are manually written, the system provides a considerable amount of test coverage for the positive test cases.