Research On Multi-tier Distributed Application System Based On COM+

During more than half a century after the birth of computer, the methods of software development have changed continuously. In order to adapt to increasement of the application requirement, the academic circle advances the method of Component Based Software Development(CBSD), and the industrial circle provides efficient technical support for this new method. There are three popular component models: COM/DCOM/COM+, CORBA, EJB. The technology of COM+ belongs to the products of Microsoft as well as the OS series of Windows, and both of themcouple very well. On the most popular PC-OS--Windows, among the threecomponent models, the executing efficiency of COM+ is highest, and currently many development tools support COM+. Considering the characteristics of our project, we select the technology of COM+.The method of Component Based Software Development makes it possible that software products can be constructed quickly like putting up brickes. Within this procedure we not only shorten the period of development, but also improve stability and reliability of application system. The characteristics of COM include: Object .Oriented, Client/Server, Language Independency, Process Transparency and Reusablity. These characteristics make CBSD possible. Using MTS and DCOM, we can create a multi-tier distributed application system, and by the aid of new functions of COM+( CLBJMDB etc), the application system will run better.I have taken part in the design and development of the project of DJKIMS during the Master Period. Making this project as an example, I will explain how to create a multi-tier distributed application system using COM+. In detail, I will analyse the levelled structure of components in subsystem and design their interfaces. In order to adapt application system to the changeful requirement, I will design a data-processing component based on data dictionary, and then provide the deployment and integration of the project of DJKIMS.