1. Mikael Johansson Lars Harrie National Land Survey of Sweden Using Java Topology Suite for Real-time Data Generalisation and Integration

2. DISPOSITION 1)Background 2)Technical environments for real-time generalisation 3)JGML 4)Outlook

3. Technical environments for real-time generalisation of GML-data 1)All generalisation performed in the database environment (i.e., before GML-data is created) 2)Solutions based on commercial products 3)XSLT-transformation 4)Task oriented API

4. All generalisation performed in the database environment + fast access methods + support for topological and geometrical queries + easy to tailor for specific data - integration is not supported - dependent on type of database system

5. Solutions based on commercial products + already implemented generalisation routines + support for topological and geometrical queries + easy to tailor for specific data - slow convertion from and to GML - dependent on type of software

6. XSLT-transformation (with java extension) + relatively fast + completely based on free standard solutions - difficult to create generalisation routines for group of objects - little support for method implementations

7. Generalisation using XSLT (Tiina Sarjakoski, Lassi Lehto) GML-file SVG-file XSLT- transformation

8. Task oriented API + developed specifically for the current problem + completely based on free standard solutions - requires much own development - tends to be data dependent (difficult with generic solutions)

9. JGML: a task oriented API for real-time generalisation and integration JGML GML-file Spatial database 1 Spatial database 2 GML XSLT transformation SVG-file User

10. JGML packages Java Topology Suite (Vivid Solutions) GML reader classes (using Xerces from Apache) Basic data classes according to OGC- standards Object type classes Generalisation classes Viewer (only for developing purposes)

11. Java Topology Suite JTS conforms to the Simple Features Specifications for SQL published by the OGC JTS provides a complete, consistent, robust implementation of fundamental 2D spatial algorithms JTS is fast enough for production use JTS is written in 100% pure Java JTS is open source

12. JGML- basic and object type classes

13. JGML- first test of generalisation

14. JGML - summary Solely based on free products Conforms to OGC-standards Good geometry and topology handling (as good as “any” commercial GIS API) Developing time: 2 persons, 1.5 months work per person.