On the coherence of component protocols

Component-based programming promises to ease the construction of large-scale applications. The construction of applications using components relies on the notion of interfaces. However, the notion of interfaces provided by current component models is restricted: In particular, it does not include behavioral information to define the protocols of the components: Sequences of service requests. The lack of behavioral information limits our trust in components: Security, reuse, and quality relate directly on this missing information. In this paper, we consider the problem of verifying if a component implementation respects the protocol specified during its design. First, we define a notion of coherence between protocols and an algorithm to verify the coherence between two protocols. Then, we describe an algorithm to extract the protocol of a component from its source code. Finally, we present a tool that enables the static verification and enforcement of the notion of coherence.