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I have a class NodeA, annotated with @NodeEntity. It has many fields, including:

@Indexed
public Double lat;

@Indexed
public Double lon;

Note that NodeA is already capable of storing enough location information via lat and lon fields. I want to add nodes of type NodeA into a spatial layer, so that I can run spatial queries using GeoPipeline.

  1. How can I add NodeA objects directly into a spatial layer? Currently, I can only add Points such as new Coordinate(13.766, 55.566) into a spatial layer. (If there is no solution, how can I associate a NodeA node with its corresponding Coordinate node?)
  2. Do I need to add the nodes into a spatial Index separately?

I am using:

  • Java in Play!Framework 2.2.2 (Can be updated)
  • Embedded Neo4j-Spatial 0.13-neo4j-2.0.1 (Can be updated)

Edit: When I connect an already existing node of type NodeA to the RTREE_ROOT, GeoPipeline complains about missing bbox property of the NodeA node. (Sure enough, there is no bbox property in NodeA, but it is present in other nodes of type Coordinate).

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2 Answers2

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I found the solution here:
http://www.markhneedham.com/blog/2013/03/10/neo4jcypher-finding-football-stadiums-near-a-city-using-spatial/

We just need to add the nodes to a spatial index. The nodes should have a wkt property which contains the coordinate information. All the nodes added to this index will be automatically added to a spatial layer as well.

IndexProviderTest.java provides an updated implementation:
https://github.com/mneedham/spatial/blob/master/src/test/java/org/neo4j/gis/spatial/IndexProviderTest.java#L251

@Test
public void testWithinDistanceIndex() {
Map<String, String> config = SpatialIndexProvider.SIMPLE_WKT_CONFIG;
IndexManager indexMan = db.index();
Index<Node> index = indexMan.forNodes("layer2", config);
Transaction tx = db.beginTx();
Node batman = db.createNode();
String wktPoint = "POINT(41.14 37.88 )";
batman.setProperty("wkt", wktPoint);
String batman1 = "batman";
batman.setProperty("name", batman1);
index.add(batman, "dummy", "value");
Map<String, Object> params = new HashMap<String, Object>();
Double[] point = {37.87, 41.13};
params.put(LayerNodeIndex.POINT_PARAMETER,
        point);
params.put(LayerNodeIndex.DISTANCE_IN_KM_PARAMETER, 2.0);
IndexHits<Node> hits = index.query(
        LayerNodeIndex.WITHIN_DISTANCE_QUERY, params);
tx.success();
tx.finish();
Node node = hits.getSingle();
assertTrue(node.getId() == batman.getId());
assertTrue(node.getProperty("name").equals(batman1));
}
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0

The blog Find Van Gogh’s artworks next to you, with Neo4j Spatial and Spring Data Neo4j 3.0.1

http://inserpio.wordpress.com/2014/04/03/artworks-spatial-search/

does exactly what I was looking for. @NodeEntity contains a wkt property, and Nodes are added to a SpatialRepository.

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