Application And Research Of J2EE Design Pattern For B2B E-Business System

The Java 2 Platform, Enterprise Edition (J2EE) defines the standard for developing multitier enterprise applications. The J2EE platform simplifies enterprise applications by basing them on standardized, modular components, by providing a complete set of services to those components, and by handling many details of application behavior automatically, without complex programming. The J2EE is recognized as particularly applicable to develop large enterprise applications.J2EE is certainly an important platform,enabling teams to build some very powerful systems.However,reality is,there is still awild semantic gap between the abstractions and services that J2EE provides and the final application that a team must build.Patterns represent solutions that appear again and again in filling that gap[1]. The J2EE patterns describe typical problems in software design for the J2EE platform,and provide solutions for these problems . The design of system can be improved remarkably by J2EE patterns, therefore it can enhance numerous aspects of the system, including maintainability, extensibility,and reusability. This paper first introduces the essential conceptions of J2EE patterns, and then chooses a B2B online ordering system for textile vocation as our concrete application to discuss how to link patterns together in best practices to design robust,efficient B2B electronic business system.While J2EE patterns offer flexible solutions to construct high-quality, reusable, evolvable components for the J2EE platform, the patterns also have introduced code tangling and code scattering within the core functionality of the J2EE components. A number of J2EE patterns involve crosscutting structures in the relationship between the roles in the pattern and classes in each instance of the pattern. Therefore, it is necessary to eliminate crosscutting structures in these patterns. Finally, a concrete application was chosen to analyze the problem of crosscutting within the implementation of Business Delegate pattern with OOP. A method to implement Business Delegate pattern using Aspect - Oriented Programming (AOP) was present, and the result shows that this method helps improving the performance of J2EE Applications, including better code locality, maintainability, extensibility, and reusability.