Test data generation for web application using a UML class diagram with OCL constraints

In this paper, we report on our current work toward efficient and effective verification of web application's basic design. We use a UML class diagram with Object Constraint Language (OCL) to describe the application behaviors and data constraints. Then we generate test data from the formally represented specifications. We make the observation that key web application behaviors can be captured through table size constraints as well as data constraints like foreign key constraints. Based on the observation, we translate the OCL specification into the equivalent constraints using table size expressions. We present a scheme to generate test data from the translated constraints using a Satisfiability Modulo Theories solver. We employ two techniques to reduce constraints. The first is string handling and the other is decomposition of table structures. We also report on an experimental result of test data generation. The result indicates a potential that our scheme works well for real applications in reasonable times.