Research And Application Of Software Patterns

Due to the degree in which computer software is constantly increasing, software development is facing an unprecedented challenge. Developing reusable software has been seen as a feasible solution to solving this software crisis, and as a way to improving both productivity and quality of software. We use design patterns to record design knowledge. When comparing the different technologies, design patterns are more abstract, more reusable and more flexible than component technology and framework technology.Set in motion by the Internet/Intranet technologies, enterprise applications software are based on the distributed N-tier network architecture of the client/server model. They have become very complex, involving a variety of technologies, and therefore demanding highly-experienced staff. Under these conditions, it is essential to use design patterns in the construction of software. This paper discusses the contexts and consequences of applying patterns in developing ISMP (Integrated Services Management Platform) by J2EE architecture for the telecommunication enterprise.This paper researches the following:1. Design patterns provide strong support to reusable software.2. Architecture for the ISMP (Integrated Service Management Platform) management centre is separate-layered, including: a presentation layer, a business logic layer and a database layer. This kind of architecture is low-maintenance, as changes in one layer don't influence other layers. This results in the application system being more stable, flexible, extensible and reusable.3. The contexts and the consequences of applying design patterns in ISMP. J2EE architecture is very complex because it involves many differing standards and technologies. To develop feasible, reusable and extensible application software, design patterns are involved in the application of J2EE architecture.4. In Web Layers, it discusses suggestions for handling requests, controlling access, and verifying input. Firstly handling requests is designed and realized by the Intercepting Filter Pattern. Secondly, controlling access is designed and realized by the Front Controller Pattern. Thirdly, verifying input is realized by the View Helper Pattern.5. In business layers, it discusses the contexts of applying the Business View Pattern and the Service Locator Pattern for improving the construction and the performance. It designed by the Business View Pattern to reducing the coupling between the presentation layer and the business layer and to buffer the results. It is designed by the Service Locator Pattern to provide unified access services interface to the client.