Porting OMTTs to CORBA

The Common Object Request Broker Architecture standardizes a platform- and programming-language-independent distributed object computing environment. It also provides a standard for several distributed services. The Object Transaction Service provides an object-oriented framework for distributed transaction processing, especially for Online Transaction Processing in business applications. The current CORBA OTS allows multi-threading inside a transaction, leaving, however, thread coordination to the application programmer, which can be dangerous. Based on the Open Multithreaded Transaction model, we present in this paper the design of a Thread Synchronization Coordinator, ThreadSyncCoordinator, which provides the desired thread control inside a multithreaded transaction. A blocking commit protocol ensures that once in a transaction, a thread cannot leave before the outcome of the transaction has been determined, guaranteeing the ACID properties for multi-threaded transactions. We also show how the ThreadSyncCoordinator can be used to design and implement complex applications, e.g., an Online Auction System, in an elegant way.