Event-Based Input Validation Using Design-by-Contract Patterns

This paper proposes an approach for validation of numerical inputs based on graphical user interfaces (GUI) that are modeled and specified by event sequence graphs (ESG). For considering complex structures of input data, ESGs are augmented by decision tables and patterns of design by contract (DbC). The approach is evaluated by experiments on boundary overflows, which occur when input values violate the range of specified values. Furthermore, a tool is presented that implements our approach enabling a semi-automatically detection of boundary overflow errors and suggesting correction steps based on DbC.