MapGIS-based Map Service System Designing And Implementation

21 century is a time of information technoledge and a time of Internet.With the development of computer tech,network communication tech and earth spatial tech,especailly the Internet and Web as an important developing trend of the future computer tech,traditional GIS has been developed in the trend of information sharing network GIS.With the increasing spatial information resource of the internet,more and more Web site,such as Google,MapBar,E-city, have provided map service to the civilians.GIS are becoming the civilian-oriented information tools.Comparing to the other information system,the map service system model has its own features.First its data sources are much richer.including not only the massive property information of geographical points and their location information.Second the data to be processed is huge compares to the thounds of MISsystem records.A small city may contain several GB data.Finally the business logic is more complex.It provides not only the geographical information searcg but also the spatial seach,multiple civilian utility services.Map information library may also be required to be integrated with exsiting information system. Because it provides civilian services.in order to attract more users,Internet will be the main media.Thus B/S structure will be preferable.All these determines a well formed system architecture is required for the map service system..With modern software design theory and new software tech.this paper uses design patterns and enterprise patterns to provide reasonable design schma and applied these techniques to the practical project.This paper describes how to build map service system application framework based on mapgis map showing tech.Based on practial project,it analyzes the requirements details and provide the USE CASE graphics.The map service system decided its complex system structure,thus system extensiablity and health should be considerd carefully.Basic on these,the paper discusses the hardware and software structure of the system,dividing the system into presentation layer,logical layer and data layer. Data layer is designed for database-based,network-based and file-system-based implementation, providing an available data access strategy.Logical layer uses techs such as Lazy Load,data cache etc.It alo provides ways for distribution system and the interaction patterns with presentation layer.Presentation layer mainly describes the basic theory of web-based map presentation.Using Ajax,it provides a no-refreshing interaction method with client browsers. And again it discusses the strategy of system integration and distribution application of the map service system designing to fulfill practical requirements.Finally it describes the system performance and designing shortcomings and generalizes the design keys.This paper contains seven chapters:Chapter 1 describes the goal and meaning of the paper.Also it provides the main research work contents.Chapter 2 discusses the map service system requirements.It provides the hardware and software structures of system designing.And it also discusses the designing issues of distribution and system integration.Chapter 3,4 and 5 are the center of the paper and they discuss the data layer.logical layer and presentation layer models in detail.Chapter 3 describes the data layer designing issues,According to the feature of GIS system it introduces the process ways of data source and provides a database-based data model.Chapter 4 discusses in detail the implementation and designing issues of logical layers.First it introduces the server side and client side framework designing schemas of logical layer.Then it discusses logical-presentation layer,logical-data layers and inner logical layers implementation solutions.Chapter 5 introduces the presentation designing issues and discusses the MapGIS-IMS map view theory.client-server interaction means and the basic map function implementations.Chapter 6 describes the performance issues of the system and discusses the defect of the system designing.Chapter 7 is the summary chapter.It generalizes the system design issues and provides the author's own opinions.