- Choose bandwidth (radius).
- For each point, add kernel-weighted contribution to grid cells within bandwidth.
- Normalize by kernel sum.
9. Performance tuning and memory management
- Stream features: use FeatureIterator and FeatureWriter rather than loading whole collections.
- Use spatial indexes for in-memory operations.
- Push operations to spatial databases when possible (PostGIS is highly optimized).
- Process rasters block-by-block and avoid materializing large arrays.
- Use simpler geometries (linearring vs complex multipolygon) where possible; apply TopologyPreservingSimplifier.
- Tune JVM (heap size, GC) for large batch jobs.
- Use Profiler and heap dumps to find hotspots and memory leaks.
10. Testing, debugging, and deployment tips
- Unit test geometry operations with known fixtures; use small CRS-aware examples.
- Visualize intermediate results with GeoTools’ rendering or export GeoJSON for quick inspection in QGIS.
- Use logging at debug level for Geotools modules; capture exception stack traces for CRS and transform errors.
- For production, prefer containerized deployment with fixed GeoTools version to avoid classpath conflicts.
- When upgrading GeoTools, run regression tests—geospatial libraries can change behavior subtly between versions (CRS axis ordering, precision models).
11. Further reading and resources
- GeoTools user guide and Javadocs (project site)
- JTS Topology Suite documentation for advanced geometry ops
- PostGIS documentation for pushing spatial SQL to the database
- Example projects and workshops (GeoServer, GeoMesa) for large-scale geospatial processing
This article provided practical techniques and examples for advanced spatial analysis with GeoTools: CRS handling, geometry/topology, spatial indexing, raster-vector workflows, geoprocessing pipelines, and performance considerations. The code snippets are sketches—adapt to your GeoTools version and project needs.
Leave a Reply