NoSQL Geographic Databases: An Overview - Geographical Information Systems: Trends and Technologies - page 95

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GraphDatabaseService database = new
EmbeddedGraphDatabase(storeDir);

try {

ShapefileImporter importer = new
ShapefileImporter(database);

importer.importFile("shp/br_municip.shp",
"MUNICIPALITIES",
Charset.forName("UTF-8"));
importer.importFile("shp/pois.shp", "POIS");
importer.importFile("shp/highways.shp", "HIGHWAYS");

} finally {
database.shutdown();

}
...

Fig. 15. Converting shapefi les into Neo4j Spatial.

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try {

SpatialDatabaseService spatialService = new
SpatialDatabaseService(database);

Layer layer1 = spatialService.getLayer("MUNICIPALITIES");
SpatialIndexReader spatialIndex1 = layer1.getIndex();

Search searchQuery1 = new SearchCQL(layer1,
"name = 'New York'");
spatialIndex1.executeSearch(searchQuery1);
List<SpatialDatabaseRecord> newYork =
searchQuery1.getResults();

Envelope nyBBOX =
newYork.get(0).getGeometry().getEnvelopeInternal
();

Layer layer2 = spatialService.getLayer("POIS");
SpatialIndexReader spatialIndex2 = layer2.getIndex();
Search searchQuery2 = new SearchCQL(layer2, "type =
'restaurant' AND
bbox(nyBBOX.getMinX(),nyBBOX.getMaxX(),
nyBBOX.getMinY(), nyBBOX.getMaxY())");

spatialIndex2.executeSearch(searchQuery2);
List<SpatialDatabaseRecord> rests =
searchQuery2.getResults();

for (SpatialDatabaseRecord rest : rests ) {
Search searchQuery3 = new
SearchIntersect (rest.getGeometry(),newYork.ge
t(0).getGeometry());

...

}
...
} finally {
database.shutdown();

}

...

Fig. 16. An excerpt of the algorithm that answers Q1 in Neo4j Spatial.