Analyse And Application Of Design Patterns In J2EE

The increasing scale and complexity of software challenges software development dramatically. Software reuse has been seen as a feasible means to solve the software crisis and to improve both productivity and quality of the software. Design pattern is a higher level, more abstract and more effective method of software reuse. The application of design pattern is helpful to plan the system frame design and measure off functions from whole level at the beginning of system construction, this make the subsequent development more regular and guaranteed. This thesis discusses the design pattern as well as its strong support for software reuse according to practice experience in a real J2EE project.This paper discussed and summarized the character of J2EE design patterns based on GoF's design patterns. According to a J2EE project, firstly, this paper introduces a complete new, convenience and high effect method for web layer with design patterns of compose and view assistant, after analyses and compares some technologies at current time. This method expresses the attributes and format of page with XML file. The new technologic frame for web layer can make the development of web layer and logic layer independent.; secondly, this paper explains a excellence frame-Hibernate of Object-Relation Mapping and it's design patterns of single "one-to-many", dual "one-to-many" in data persistence layer. The application of Hibernate in data persistence can make the system more flexible and more easily to adapt to the change ; finally, this paper analyses the merits of packing Hibernate with design pattern of Data Access Object.