在 CORBA 環境上的物件異動與多重存取控制服務

Abstract

隨著物件導向的技術的日趨成熟，其應用的領域也越來越寬廣。如何將 物件導向的技術 應用在分散式計算環境 (Distributed Computing) 的 領域也成了熱門的研究方向。在 這方面，OMG (Object Management Group) 扮演著標準推動者的角色。OMG 於 1990 年 提出了一套分散式 物件環境的標準 CORBA (Common Object Request Broker Architecture)，並不斷地繼續改良，目前是受業界重視的開放式物件環 境的標準。 本篇論文即在 CORBA 所提供的物件聯結的環境下，建立 分散式的物件異動服務 (Object Transaction Service) 與多重存取控制 服務 (Concurrency Control System)，以使得 在分散式物件環境下開 發資料異動或特殊需求的軟體時，能更迅速有效。 CORBA, the emerging standard of distributed object technology, providesthe interconnection bus between distributed objects. Base on CORBA, we provide two add-on objects -- object transaction service and concurrency control service. The concept of transaction is useful not only in database but also in building robust mission-critical applications. On the other hand, concurrency control is key to coordinate concurrent processes that have some resources in common. With these two components in hand, one can build the distributed, reliable software in a much easier way. This thesis presents the implementation and integration of the object transaction service and concurrency control service based on CORBA. In transaction service, We provide not only the basic flat transaction model but also the nested transaction model. Nested transaction provides isolation of failures and enhances the concurrency of long-lived transaction. On the other hand, concurrency control service allows the flexibility that one can arrange the lock granularity and duration on his own.