Java Program Verification via a Hoare Logic with Abrupt Termination

The version of the following full text has not yet been defined or was untraceable and may differ from the publisher's version. Java P ro g ra m V erificatio n v ia a H oare Logie w ith A b r u p t T erm in ation A b s tr a c t. This paper formalises a semantics for statem ents and expres­ sions (in sequential imperative languages) which includes non-termina­ tion, normal term ination and abrupt term ination (e.g. because of an exception, break, return or continue). This extends the traditional se­ mantics underlying e.g. Hoare logic, which only distinguishes termination and non-termination. An extension of Hoare logic is elaborated th a t in­ cludes means for reasoning about abrupt term ination (and side-effects). It prominently involves rules for reasoning about while loops, which may contain exceptions, breaks, continues and returns. This extension applies in particular to Java. As an example, a standard pattern search algorithm in Java (involving a while loop with returns) is proven correct using the proof-tool PVS.