Common Contracts
1 similar Cooperation Contracts contracts
Cooperation ContractsCooperation Contracts • November 8th, 2007
In this paper we introduce the concept of cooperative message handling, in which several objects act together in answering a message they have received jointly. Co- operative message handling extends the traditional message passing paradigm which requires the receiver of a message to be a single object only. Cooperative messages are de ned with cooperation contracts which are established between several object types. A cooperative message is sent to a tuple of instances, one for each object type in the cooperation contract. We show that cooperation contracts o er new bene ts for behavior modeling in object-oriented database design. Behavior which is provided by several object types in concert needs not be dispersed and can be de ned in a sin- gle place. Furthermore, behavior designs become symmetric, better maintainable and better extensible.
