Type-safe trading proxies using TORBA

Nowadays, autonomous distributed systems, such as large-scale telecom and manufacturing applications, rely on the use of middleware. In order to find back resources and to interconnect applications, the middleware has to provide a trading function. Unfortunately, standard traders such as the ODP/OMG CosTrading service, are error-prone due to the lack of type checking at compilation time, but only performed at runtime. In order to address this problem, we have defined the Trader Oriented Request Broker Architecture (TORBA) to provide a trading framework and its associated tools, which tend to offer type-safe trading operations that are simple to use from applications and checked at compilation time. Based on the concept of Trading Contracts, a resource is described using the TORBA Definition Language, and then compiled to generate trading proxies offering simple interfaces to applications. The example used in this paper clearly states the benefits brought by the TDL trading contracts: type checking at compilation time, simple to use, and providing a powerful and reliable framework for CORBA object trading.