Complete contracts through specification drivers
  Existing techniques of Design by Contract do not allow software developers to specify complete contracts in many cases. Incomplete contracts leave room for malicious implementations. This article complements Design by Contract with a simple yet powerful technique that removes the problem without adding syntactical mechanisms. The proposed technique makes it possible not only to derive complete contracts, but also to rigorously check and improve completeness of existing contracts without instrumenting them. 
Alexandr Naumchev, Bertrand Meyer
cs.SE