基于Web的信息系统设计与实现

Abstract

随着因特网应用的迅速普及，基于Web信息系统逐渐成为当前的开发热点。信息系统的设计通常围绕着信息的采集、存储、检索、发布以及安全性控制、权限管理等问题展开。由于存在着相似之处，因此，设计信息系统常常需要解决一些共同的问题，如会话管理、信息组织、权限控制等。能否针对这些问题提出相应的解决办法对于缩短系统开发周期，提高工作效率具有重要意义。本文结合石化市场Web信息系统的设计，对基于Web的信息系统设计以及实现技术作了一些探讨。石化市场Web信息系统采用多层客户机／服务器的软件结构模式，通过“瘦客户”与应用服务器配置方案，使系统易于发布、安装、配置并具有良好的兼容性。系统功能设计采用模块化的设计思想，会话管理模块利用软件构件加以实现，该构件提供了会话创建、分配、关闭及超时处理等会话管理的相关操作。为解决信息组织的一致性问题，系统设计方案中引入了“刊物”的概念，将文件类信息与数据库记录的组织统一了起来，简化了信息查询模块的程序设计工作。权限管理的实现同样采用了软件构件技术，并提供了图形化的管理工具。此外，石化市场Web信息系统还利用HTML文档模板技术实现了Web页面动／静态内容的分离，简化了编程工作，提高了工作效率。石化市场Web信息系统作为一个有代表性的应用实例，其设计思路及实现技术为其它同类信息系统的设计提供了参考。As the Internet application grows at an amazing speed, Web-based information system became more and more popular. The design of such systems often deals with how to collect, store, search, and present information and how to protect the system security and control users' access. Here are some common problems that we usually meet when designing a web-based information system, such as session control mechanism, information organization, access control, etc. It's important to find solutions for such problems in order to shorten developing period and cut down the cost of software. The thesis uses an example of Petro-chemical product market information system and tries to illustrate the design and implementation of web-based information system. Petro-chemical product market information system uses a multi-layer Client/Server software architecture. By using thin-client and application server, the system can be distributed, installed, configured, and maintained easily. It also gains better compatibility. The design of the system is divided into modules. Session control module is implemented as a software component. This component provides the operations to create, allocate, close and time-out sessions. The system uses journals to organize information files and database records together so that information query module can be more simple. access control also takes the advantage of software component, it also provides graphic administrative tool. The system also uses HTML templates to separates the dynamic and static contents of a web page. The thesis gives an typical example of the design and implementation of web-based information system. It can be a reference to the designer of such systems