Invited Talk: JML framed!

Abstract

This talk will try to frame JML in two senses. The first is the sense of placing JML in the context of other specification languages and tools. This context will be provided by giving a brief introduction to JML, with small examples. The different tools that work with JML also help provide context for the language design in a different way. Another aspect of this context is provided by comparing JML with other design by contract languages, such as Eiffel.The second sense of framing in JML is the more technical one of frame axioms, also known as "modifies clauses". Such frame axioms are critical for reasoning, and are difficult to check at runtime; hence static analysis is a crucial need. We will discuss the semantics of JML's frame axioms, including datagroups, both in a naive sense and with the experimental Universe type system. Both problems in the semantics and checking, as well as some recent work will be presented. Note that some of the recent work on frame axioms in JML, especially extensions with the Universe type system, is joint work with Peter Müller (of ETH Zürich) and Arnd Poetzsch-Heffter of (U. Kaiserslautern). At Iowa State, the development of JML was partially funded by the (US) National Science Foundation under grants CCR-9503168, CCR-9803843, CCR-0097907, and CCR-0113181.