A Framework for Analysing the Effect of "Change" in Legacy Code

We propose a sound and practical approach, based on a formal method (known as Interval Temporal Logic), to cope with ‘change’ and analyse its effect. The approach allows us to capture a snapshot of system’s behaviour over which various interesting properties, such as liveness, timeliness and safety properties, can be validated compositionally. These properties may include invariants that are required to be valid after changes have taken place. We also present and evaluate the design and implementation of a formal tool, AnaTempura, which supports the developed approach. A case study is presented to illustrate our approach and the tool.