J2ee-based Distributed Network Of Geographic Information Services To Explore

The development of Internet provides the WebGIS with technical support for its development and application, and the conception of "digital earth" establishes the direction of WebGIS's development. "digital earth"emphaise multi-scale, network, visualization and integration of global information. These require that the independent and closed WebGIS should turn to the open WebGIService, and the geographic information and GIS functions will be the sharable resource on the Internet truly. So the key questions of WebGIService are managing massive geographic information and taking advantage of Internet resource to improve the efficiency and quality of its service.The Distributed WebGIService based on J2EE is a technical system, which is built on the Internet, manages massive, multi-source geographic information and GIS functions distributedly and expresses the geographic information with multi-dimensions. It studies and practices some contents of the WebGIService:Building a Distributed WebGIService based on J2EE, it is independent of operation and easy to integrate on the Internet;Building a O-O data model of GIS, it is easy to expand, access and manage;Building a spatial data accessing engine, it can finish majority works of spatial data and manage big range and multi-scale geographic information. With the help of agent server, spatial data server will be managed, so the spatial data can be stored and managed distributedly.Building a function agent server, it can manage the geographic information query services based on attribute and spatial, this validate that the GIS functions can be distributed on the Internet;Realizing the 2D and 3D expression of geographic information and browsing the geographic information with multi-scale and immensely.