The Research & Realization Of WebGIS's System Frame & Service Engine

The latest development of the computer network technology is promoting the upgrading and fast developing of GIS technology, so the realization of GIS on internet arouses the attention from people. In recent years, WebGIS is a hot issue and an important developing direction in the research of GIS.There are two main applications the field of WebGIS in china: Internet and Intranet. The main application on internet is map info issuing, browsing and searching; the main application on intranet is map info issuing between departments. WebGIS is a prototype of "digital earth" or "digital city".On the basis of GIS and network frame, this paper brings up the WebGIS service frame, and describes map issue and bus interchange from requirement analysis to specification in detail. In the analysis and research, this paper incorporates OOP and design pattern in the process of development; and process unit test and performance test use map issues module, find the factors affect the system also.The paper uses scientific developing flow, reasonable project management and developing process is the basic of successful project development. The paper use the following skills in the whole process: system cascade; modular; requirement drive the process of development; modeling using UML; the link of Ant, JUnit and JCoverage to daily build.The design focuses on the optimizing and upgrading performance as well as insuring the system stabilization. Pretreatment and pre-download of map data and the arithmetic in bus interchange get good result in practical application.