Research On The Technology Of Component For Web Application Based On OSGi

With the development of science, technology, culture and economy, especially the great development of computer network and communication technology, more and more software functions appear, and change of demand becomes more and more frequent in the Web applications. At the same time, complexity and difficulty of developing the Web applications is also growing at an alarming rate. Therefore, the concept of components has more and more attention in software area. In the current, many Java projects have some frameworks for components, but they do not have coincident standard. However, OSGi offers a coincident and standard solution, and it is good at deployment and management of systems. The OSGi is a lightweight, loosely coupled and service-oriented development framework for application. It is originally applied to embedded area, because of its modularity, dynamic performance, high reusability and efficiency and other advantages, gradually adopted by desktop and Web applications.Thus, the thesis studys and implements component-based development of Web applications based on the OSGi. UMS (United Management System) is as a research platform to build component through relevant mechanisms of OSGi to form a new deployment scheme to improve the performance of UMS platform, as well as to improve the efficiency of development and maintenance. The main work is as follows:1.This thesis discusses ways of integrating the Web and OSGi, analyzes several kinds of the OSGi framework and selects the frameworks which are used in the thesis. At the same time, the thesis designs an application-level microkernel architecture, and analyses the component-based principles and process.2.Based on the above schemes, this thesis designs and implements the components for the UMS, and in details, shows the formation of specific components in the UMS from four aspects which are analysis and classification of components, building of common components, building of functional components and deployment of components according to the above process. At the same time, the thesis explains how to solve the sharing of resources and decoupling of dependency in the process.3.The results of implement are analyzed and discussed from modular, dynamic, scalable and running performance. Original system and component-based system are compared, and differences between them are researched.The results show that the modular and dynamic performance of new systems are met, stability has been strengthened, efficiency of development and maintenance has been greatly improved.