Design And Research Of Components For Interactive Mobile GIS Based On J2ME

The mobile GIS which could be applied to various fields is a complementarity to the traditional GIS. For the rapid development of the hardware and software on mobile devices, mobile GIS has break through the technical bottleneck and be used in wide area of the mobile devices. By far, however, vast majority of the mobile GIS work locally, which means the GIS data such as electronic map are usually stored in local device and processed by professional software to do some operation of locating or navigating. This makes the GIS data could not be shared or updated among different devices as well as the GIS application software could not be transplanted to other hardware for the software were developed in different platform. Thus constructing a mobile GIS framework which could be easily transplanted and has the ability of data interaction is of very necessary.The J2ME platform, as known as the Java 2 Micro Edition, is a micro edition of Java platform developed by Sun Corporation and mainly used in mobile devices. Compared with other develop platform, J2ME has strong ability of transplant which is known as "programmed once, run anywhere". The mobile devices could load and run the J2ME application as long as they support the needed CLDC and MIDP profiles. Thanks to these characters, J2ME has been widely taken into the development of the mobile GIS.This article dose research works on the design of the components in J2ME platform and introduces a set of mobile GIS client components using the concept of block and framework after the limitation of the current mobile GIS and its technology have been analyzed. The core of these components is a framework extended from the MVC model on which the other function blocks are based. By implementing and extending the components, programmers could develop more location based services easily. Further more, J2EE and MapXtreme For Java are used in this article to establish a GIS server to receive and response the requests of the mobile client, as well as share data between them. In the end of the article, a simple mobile GIS application is realized based on the components designed above.