| This project focuses on the design and implementation of student grade management system using component-based middle-tier distributed applications. Object-oriented design and component technology paradigms are used to analyze and design this GRADER application. The implementation is based on the Java language Enterprise Java Bean (EJB) and J2EE application server. Three different distributed architectures: DNA, CORBA and J2EE, are introduced and compared to give an overview of the current distributing computing technologies. By partitioning three or more tiers to a Web application, each tier can be logically and may physically separated from each other to present better design patterns and improve overall Web application reliability and scalability. All application services are also distributed in each tier, including clients on the front end, data resources on the back-end, and one or more middle tiers between them where business logic of the application should stay. The middle tier implements as EJB component, and hence has good reusability and hides the client tier from the complexity of the enterprise, and takes advantage of rapidly maturing Internet technologies to minimize user administration and good portability. Transparent access allows clients to interact with remote servers regardless of physical component location. The underlying infrastructure takes care of locating any server resource. Java security mechanism is also discussed in this project. |
