用JAVA开发WebGIS小应用程序

Developing WebGIS Applet with JAVA

该研究旨在开发 Web GIS软件平台 ,研究系采用 JAVA来开发 Web GIS小应用程序 .该文介绍了所开发的被称之为“地学之窗”Web1.0 Web GIS软件的技术特点 ,包括软件界面、主要功能、数据组织方式、数据调度策略、显示控制机制等 .根据实际应用与测试 ,该软件在高速网环境下效果良好 ,在低速网环境下效果不佳 ,即“浏览器 /小应用程序”两层架构的 Web GIS可应用于高速网环境 ,在低速网环境应改进系统的体系架构和调度策略 .最后提出了几点经验与思考 ;总结了 JAVA语言在不同浏览器上的功能差别 ,并给出了解决途径 ,另外 ,还分析了地学之窗 Web1.0运行效率的瓶颈 ,并指出了改进途径 .

The research target is developing WebGIS. JAVA applet is used in “Browser/Applet” Two Tier Architecture. Next is the work theory of “Browser/Applet” Architecture Web GIS applet. A WebGIS software——GeoWindos Web1 0 is formed in the research. Technique features of GeoWindows Web1 0, including interface, function, data managing strategy, display controlling mechanism and so on, are introduced in the paper. The running test result of GeoWindows Web1 0 is reported.By testing,GeoWindows Web1 0 works very well in high speed Intranet, too slowly in dial up way. Some experience and thinking of author about WebGIS are given. Some differences of JAVA working in different Browsers are discussed, and the solving methods are given. The author thinks that the running speed bottleneck of GeoWindow Web1 0 is data loading speed. The importance of integrating with HTML, JAVA, JavaScript predominance in WebGIS is emphasized in the paper.