The Code Contracts project [3] at Microsoft Research enables programmers on the .NET platform to author specifications in existing languages such as C# and VisualBasic. To take advantage of these specifications, we provide tools for documentation generation, runtime contract checking, and static contract verification. This talk details the overall approach of the static contract checker and exa...

In this paper we describe a methodology and experience of simulation-based verification of microprocessor units based on cycle-accurate contract specifications. Such specifications describe behavior of a unit in the form of preconditions and postconditions of microoperations. We have successfully applied the methodology to several units of the industrial microprocessor. The experience shows tha...

jContractor is a purely library based approach to support Design By Contract specifications such as preconditions, postconditions, class invariants, and recovery and exception handling in Java. jContractor uses an intuitive naming convention, and standard Java syntax to instrument Java classes and enforce Design By Contract constructs. The designer of a class specifies a contract by providing c...

We study the relation between specifications of component behaviors and contracts providing means to specify assumptions on environments as well as component guarantees. We show how a contract framework can be built in a generic way on top of any specification theory which supports composition and specification refinement. Our contract framework lifts refinement to the level of contracts and pr...

In this cand.scient. thesis we propose a strategy for testing validity of decomposition of contract oriented specifications. The strategy is based on Abadi and Lamport’s Composition Theorem for the Temporal Logic of Actions and test case generation from executable specifications. A composition rule, inspired by the Compositon Theorem, is formulated in a semantics based on timed streams. A subse...

We describe a new approach to employing specifications for software reliability. Rather than only using specifications to validate implementations, we additionally employ specifications as a reliable alternative to those implementations. Our approach, which we call Plan B, performs dynamic contract checking of methods. However, instead of halting the program upon a contract violation, we employ...

Manifest contracts combine the rich specifications and runtime checking of higher-order contracts [11] with a static type discipline. Conventional type systems prevent simple errors, like calling a boolean as a function, but manifest contracts can prevent more complex errors. For example, we could give the sqrt function the very precise type {x:Float | x ≥ 0} → {y:Float | |x − y| < }, where sub...

Design by contract approach prescribes that developer should define formal and verifiable interface specifications for software components and makes it possible to automate process of software testing. We propose to adapt this approach for Extended Finite State Machines (EFSMs), which are often used in model-based development and for modeling VHDL specifications. This paper proposes an approach...

For distributed object or component systems based on CORBA or DCOM, a suitable software architecture and a strong separation of modules is necessary. Our object coordination net approach (OCoN) allows mixed event and state based true concurrent modeling. It describes contracts, object scheduling, resource handling and the abstract data and control flow of services. A seam-data and control flow ...

The article discusses problems of model based test construction and ways of their solution using different kinds of models (operational, contract, axiomatic, and historybased specifications). The main idea is that the integration of model based techniques having different underlying formalisms can give valuable practical results in test construction. The idea is illustrated by successful applic...