2
votes

I'm running Neo4j 2.0.1. together with the spatial plugin for 2.0.1. together with the JDBC driver for 2.0.1. I created a simple point layer and an index for doing a spacial query. If I type in the following query in the browser, the respective nodes are returned:

START n=node:geom('withinDistance:[15.0,60.0, 200.0]') RETURN n

I wrote a method in my servlet to send this query:

   //connect to database
   try {
            if(connection == null || connection.isClosed())
            {

                Class.forName("org.neo4j.jdbc.Driver"); // load jdbc driver
                connection = DriverManager.getConnection("jdbc:neo4j://localhost:7474"); 

            }
        } catch (SQLException e) {
            System.out.println("could not connect do DB: <br>" + e.getCause()
                    + "<br>" + e.getMessage());

        } catch (ClassNotFoundException e) {
            System.out.println("Could not load JDBC DRIVER");
            e.printStackTrace();
        }

Then, I'm trying to send a request to the server:

    @Path("findRange")
    @GET
    @Produces(MediaType.TEXT_HTML)
    public String findRange(@QueryParam("lat") double lat,
             @QueryParam("lon") double lon,
             @QueryParam("d") double distance)
    {
        connectToDbIfNecessary();
        try(PreparedStatement p = connection.prepareStatement(FIND_WITHIN_RANGE))
        {
            p.setObject(1, lat); 
            p.setObject(2, lon); 
            p.setObject(3, distance);
            ResultSet rs = p.executeQuery();
            return getServerResponse(rs);


        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            return "failure during geospatial query:\n"+e.getErrorCode()+"<br>\n"+e.getMessage()+"<br>"+e.getCause();
        }

    }

The prepared statement I'm sending is:

private static final String FIND_WITHIN_RANGE = "START n=node:geom('withinDistance:[{1},{2}, {3}]') RETURN n";

When I execute this on my Tomcat 7.0.53, I get the following exception:

failure during geospatial query: 0 Error executing query START n=node:geom('withinDistance:[{1},{2}, {3}]') RETURN n with params {3=1.0E8, 2=60.5, 1=14.9} java.lang.RuntimeException: Error executing cypher statement(s) [{code=Neo.DatabaseError.Statement.ExecutionFailure, message=null, stackTrace=java.lang.NullPointerException at org.neo4j.gis.spatial.indexprovider.LayerNodeIndex.query(LayerNodeIndex.java:249) at org.neo4j.gis.spatial.indexprovider.LayerNodeIndex.query(LayerNodeIndex.java:293) at org.neo4j.cypher.internal.spi.v2_0.TransactionBoundExecutionContext$NodeOperations.indexQuery(TransactionBoundExecutionContext.scala:166) at org.neo4j.cypher.internal.compiler.v2_0.spi.DelegatingOperations.indexQuery(DelegatingQueryContext.scala:113) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations.org$neo4j$cypher$internal$compiler$v2_0$spi$ExceptionTranslatingQueryContext$ExceptionTranslatingOperations$$super$indexQuery(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations$$anonfun$indexQuery$1.apply(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations$$anonfun$indexQuery$1.apply(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext.org$neo4j$cypher$internal$compiler$v2_0$spi$ExceptionTranslatingQueryContext$$translateException(ExceptionTranslatingQueryContext.scala:149) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations.indexQuery(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.DelegatingOperations.indexQuery(DelegatingQueryContext.scala:113) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anonfun$2$$anonfun$applyOrElse$2.apply(EntityProducerFactory.scala:66) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anonfun$2$$anonfun$applyOrElse$2.apply(EntityProducerFactory.scala:64) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anon$1.apply(EntityProducerFactory.scala:35) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anon$1.apply(EntityProducerFactory.scala:34) at org.neo4j.cypher.internal.compiler.v2_0.pipes.StartPipe$$anonfun$internalCreateResults$1.apply(StartPipe.scala:34) at org.neo4j.cypher.internal.compiler.v2_0.pipes.StartPipe$$anonfun$internalCreateResults$1.apply(StartPipe.scala:33) at scala.collection.Iterator$$anon$13.hasNext(Iterator.scala:371) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator$$anonfun$hasNext$1.apply$mcZ$sp(ClosingIterator.scala:38) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator$$anonfun$hasNext$1.apply(ClosingIterator.scala:37) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator$$anonfun$hasNext$1.apply(ClosingIterator.scala:37) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator.failIfThrows(ClosingIterator.scala:91) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator.hasNext(ClosingIterator.scala:37) at org.neo4j.cypher.internal.compiler.v2_0.PipeExecutionResult.hasNext(PipeExecutionResult.scala:166) at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:327) at scala.collection.convert.Wrappers$IteratorWrapper.hasNext(Wrappers.scala:29) at org.neo4j.cypher.internal.compiler.v2_0.PipeExecutionResult$$anon$1.hasNext(PipeExecutionResult.scala:74) at org.neo4j.server.rest.transactional.ExecutionResultSerializer.writeRows(ExecutionResultSerializer.java:291) at org.neo4j.server.rest.transactional.ExecutionResultSerializer.statementResult(ExecutionResultSerializer.java:103) at org.neo4j.server.rest.transactional.TransactionHandle.executeStatements(TransactionHandle.java:251) at org.neo4j.server.rest.transactional.TransactionHandle.commit(TransactionHandle.java:189) at org.neo4j.server.rest.transactional.TransactionHandle.commit(TransactionHandle.java:109) at org.neo4j.server.rest.web.TransactionalService$2.write(TransactionalService.java:198) at com.sun.jersey.core.impl.provider.entity.StreamingOutputProvider.writeTo(StreamingOutputProvider.java:71) at com.sun.jersey.core.impl.provider.entity.StreamingOutputProvider.writeTo(StreamingOutputProvider.java:57) at com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:306) at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1437) at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349) at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339) at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416) at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537) at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:699) at javax.servlet.http.HttpServlet.service(HttpServlet.java:848) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:698) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1506) at org.neo4j.server.rest.security.SecurityFilter.doFilter(SecurityFilter.java:112) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1477) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:503) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:211) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1096) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:432) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:175) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1030) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:136) at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at org.eclipse.jetty.server.Server.handle(Server.java:445) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:268) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:229) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.run(AbstractConnection.java:358) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:601) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:532) at java.lang.Thread.run(Thread.java:722) }]

When I'm executing the query by sending a http request manually to the URL specified in the docs, I don't get an exception. I have no idea why this exception occurs. Could anyone point me in the right direction?

EDIT: It seems like index queries cannot be parameterized. However, if I do it as suggested by Stefan Armbruster, a new exception occurs (maybe this is a further problem in the 0.12 spatial implementation).

failure during geospatial query: 0 Error executing query START n=node:geom({1}) RETURN n with params {1='withinDistance:[14.9,60.5,1.0E8]'} java.lang.RuntimeException: Error executing cypher statement(s) [{code=Neo.DatabaseError.Statement.ExecutionFailure, message=only within, withinDistance and bbox are implemented., stackTrace=java.lang.UnsupportedOperationException: only within, withinDistance and bbox are implemented. at org.neo4j.gis.spatial.indexprovider.LayerNodeIndex.query(LayerNodeIndex.java:281) at org.neo4j.gis.spatial.indexprovider.LayerNodeIndex.query(LayerNodeIndex.java:293) at org.neo4j.cypher.internal.spi.v2_0.TransactionBoundExecutionContext$NodeOperations.indexQuery(TransactionBoundExecutionContext.scala:166) at org.neo4j.cypher.internal.compiler.v2_0.spi.DelegatingOperations.indexQuery(DelegatingQueryContext.scala:113) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations.org$neo4j$cypher$internal$compiler$v2_0$spi$ExceptionTranslatingQueryContext$ExceptionTranslatingOperations$$super$indexQuery(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations$$anonfun$indexQuery$1.apply(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations$$anonfun$indexQuery$1.apply(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext.org$neo4j$cypher$internal$compiler$v2_0$spi$ExceptionTranslatingQueryContext$$translateException(ExceptionTranslatingQueryContext.scala:149) at org.neo4j.cypher.internal.compiler.v2_0.spi.ExceptionTranslatingQueryContext$ExceptionTranslatingOperations.indexQuery(ExceptionTranslatingQueryContext.scala:142) at org.neo4j.cypher.internal.compiler.v2_0.spi.DelegatingOperations.indexQuery(DelegatingQueryContext.scala:113) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anonfun$2$$anonfun$applyOrElse$2.apply(EntityProducerFactory.scala:66) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anonfun$2$$anonfun$applyOrElse$2.apply(EntityProducerFactory.scala:64) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anon$1.apply(EntityProducerFactory.scala:35) at org.neo4j.cypher.internal.compiler.v2_0.executionplan.builders.EntityProducerFactory$$anon$1.apply(EntityProducerFactory.scala:34) at org.neo4j.cypher.internal.compiler.v2_0.pipes.StartPipe$$anonfun$internalCreateResults$1.apply(StartPipe.scala:34) at org.neo4j.cypher.internal.compiler.v2_0.pipes.StartPipe$$anonfun$internalCreateResults$1.apply(StartPipe.scala:33) at scala.collection.Iterator$$anon$13.hasNext(Iterator.scala:371) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator$$anonfun$hasNext$1.apply$mcZ$sp(ClosingIterator.scala:38) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator$$anonfun$hasNext$1.apply(ClosingIterator.scala:37) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator$$anonfun$hasNext$1.apply(ClosingIterator.scala:37) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator.failIfThrows(ClosingIterator.scala:91) at org.neo4j.cypher.internal.compiler.v2_0.ClosingIterator.hasNext(ClosingIterator.scala:37) at org.neo4j.cypher.internal.compiler.v2_0.PipeExecutionResult.hasNext(PipeExecutionResult.scala:166) at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:327) at scala.collection.convert.Wrappers$IteratorWrapper.hasNext(Wrappers.scala:29) at org.neo4j.cypher.internal.compiler.v2_0.PipeExecutionResult$$anon$1.hasNext(PipeExecutionResult.scala:74) at org.neo4j.server.rest.transactional.ExecutionResultSerializer.writeRows(ExecutionResultSerializer.java:291) at org.neo4j.server.rest.transactional.ExecutionResultSerializer.statementResult(ExecutionResultSerializer.java:103) at org.neo4j.server.rest.transactional.TransactionHandle.executeStatements(TransactionHandle.java:251) at org.neo4j.server.rest.transactional.TransactionHandle.commit(TransactionHandle.java:189) at org.neo4j.server.rest.transactional.TransactionHandle.commit(TransactionHandle.java:109) at org.neo4j.server.rest.web.TransactionalService$2.write(TransactionalService.java:198) at com.sun.jersey.core.impl.provider.entity.StreamingOutputProvider.writeTo(StreamingOutputProvider.java:71) at com.sun.jersey.core.impl.provider.entity.StreamingOutputProvider.writeTo(StreamingOutputProvider.java:57) at com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:306) at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:1437) at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1349) at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:1339) at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:416) at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:537) at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:699) at javax.servlet.http.HttpServlet.service(HttpServlet.java:848) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:698) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1506) at org.neo4j.server.rest.security.SecurityFilter.doFilter(SecurityFilter.java:112) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1477) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:503) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:211) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1096) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:432) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:175) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1030) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:136) at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97) at org.eclipse.jetty.server.Server.handle(Server.java:445) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:268) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:229) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.run(AbstractConnection.java:358) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:601) at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:532) at java.lang.Thread.run(Thread.java:722) }]

This issue seems similar to this one here from the mid of 2013.

2

2 Answers

3
votes

Not 100% sure, but I guess you cannot parameterize parts of index query. So replace your query having three parameters

START n=node:geom('withinDistance:[{1},{2}, {3}]') RETURN n

params 
1:15.0,
2:60.0, 
3:200.0

with a single parameter for the index search term:

START n=node:geom({1}) RETURN n

params 
1: 'withinDistance:[15.0, 60.0, 200.0]'
1
votes

As pointed out by Stefan Armbruster index queries don't seem to be parameterizable. Even with one parameter the query cannot be executed. So there are 2 options

1)old school Send a HTTP POST request to the url specified in the spatial docs

2)Create the String that is sent to the transactional endpoint manually:

String pay = "START n=node:geom('withinDistance:["+lat+","+lon+","+distance+"]') RETURN n";

Send the query to the endpoint without doing anything or replacing placeholders. The endpoint will then accept the query.