SCHEMA TRANSLATIONS BY XSLT FOR GML-ENCODED GEOSPATIAL DATA IN HETEROGENEOUS WEB-SERVICE ENVIRONMENT

摘要

The paper discusses online integration of XML-encoded datasets in the current Web services environment, especially concentrating on the required schema transformations. The approach is based on the use of a generic XML transformation technology, called Extensible Stylesheet Language Transformations (XSLT). The role of the data integration process in a layered service architecture framework is described. The basics of the applied XML technology are introduced. A case implementation, built as the prototype service of the GiMoDig project, demonstrates the benefits yielded by the approach. The required schema translations can be carried out as a single process, together with the needed coordinate transformations. The same base methodology can be applied both to query and data transformations. The declarative nature of the transformation definition, represented as templates stored in an XMLencoded text file, makes the transformation process easy to debug and fine-tune. As the final result, cross-border map visualization is presented.