Design And Implementation Of Project Management System Based On J2EE

Three-tier/multi-tier architecture is the main structure of today's large scale enterprise application. In the development of distributing enterprise application, the main architecture are given by Sun Microsystem Company, Microsoft Company and OMG To build a robust, multi-tier, reuseable and open-architecture distributing enterprise application is the frontier subject of system development.The development application based on component technology is a significant topic of object-oriented development. As an important development platform of component technology, J2EE supplies a set of simple and uniform criteria for the distributed application which designed on component-based patterns. EJB, which is the core technology of J2EE, supplies a set of standard component APIs for the rapid development of middle-tier components in large scale enterprise applications, and at the same time, it supplies flexible compatibility and characteristics of mutil-platform & mutil-producer.The thesis referenced and absorbed the frontier thinkings and technologies of the object-oriented field. In this project, the actual three-tier architecture as realized and the business logic was encapsulated in EJB components, which acted as an agent between presentation tier and resource tier;the separation between business logic and system service was realized, which enabled developers to devote their mind to the realization of business logic and improved the software quality and efficiency;the stretchable enterprise application was realized through tier-dispatched pattern, which has relax coupling relationship between tiers and each tier has its own role and the methods inside the tier will be changed without affection to the call-up relationship between tiers. The changes of customer's requirements will be adapted rapidly in this pattern.The thesis refers to the UML, and gives the analysis and modeling to the ystem through using the methods of UML, which set up solid foundation for design of the system.The thesis analyzes the all kinds of factors which can affected the system'sperformance in J2EE architecture and introduces how to improving it.At the same time, it puts forward the measures for improving the system's capability.The thesis, which analyzes security service architecture of the system, gives design of the security service to the application server based on J2EE. In the course of designing, this thesis adopts efficient methods to overcome the defects of the architecture and realized the targets introduced. In the end, two practical examples have been used to prove the measures.