UnsupportedOperationException while executing Cypher Query in Java to Neo4j Server

Question

I'm query a Neo4j Server with the following Cypher nad it works fine:

GraphDatabaseService neo4j = new RestGraphDatabase("http://my.ip:7474/db/data");
ExecutionEngine engine = new ExecutionEngine(
String myCypher = "START n = node(1234) RETURN n LIMIT 10;"
ExecutionResult result = engine.execute(myCypher);
System.out.println(result);

If I change the first line of the query to START n = node(*) RETURN n LIMIT 10; I get this ugly exception when I try to print the result:

Exception in thread "main" java.lang.UnsupportedOperationException at org.neo4j.rest.graphdb.AbstractRemoteDatabase.getNodeManager(AbstractRemoteDatabase.java:144) at org.neo4j.rest.graphdb.RestGraphDatabase.getNodeManager(RestGraphDatabase.java:33) at org.neo4j.tooling.GlobalGraphOperations.(GlobalGraphOperations.java:39) at org.neo4j.tooling.GlobalGraphOperations.at(GlobalGraphOperations.java:51) at org.neo4j.cypher.internal.executionplan.builders.GraphGlobalStartBuilder$$anonfun$createStartPipe$1.apply(GraphGlobalStartBuilder.scala:51) at org.neo4j.cypher.internal.executionplan.builders.GraphGlobalStartBuilder$$anonfun$createStartPipe$1.apply(GraphGlobalStartBuilder.scala:51) at org.neo4j.cypher.internal.pipes.StartPipe$$anonfun$1.apply(StartPipe.scala:38) at org.neo4j.cypher.internal.pipes.StartPipe$$anonfun$1.apply(StartPipe.scala:37) at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:200) at scala.collection.TraversableLike$$anonfun$flatMap$1.apply(TraversableLike.scala:200) at scala.collection.LinearSeqOptimized$class.foreach(LinearSeqOptimized.scala:59) at scala.collection.immutable.List.foreach(List.scala:45) at scala.collection.TraversableLike$class.flatMap(TraversableLike.scala:200) at scala.collection.immutable.List.flatMap(List.scala:45) at org.neo4j.cypher.internal.pipes.StartPipe.createResults(StartPipe.scala:37) at org.neo4j.cypher.internal.pipes.MatchPipe.createResults(MatchPipe.scala:31) at org.neo4j.cypher.internal.pipes.NamedPathPipe.createResults(NamedPathPipe.scala:26) at org.neo4j.cypher.internal.pipes.FilterPipe.createResults(FilterPipe.scala:28) at org.neo4j.cypher.internal.pipes.ExtractPipe.createResults(ExtractPipe.scala:37) at org.neo4j.cypher.internal.pipes.EagerAggregationPipe.createResults(EagerAggregationPipe.scala:49) at org.neo4j.cypher.internal.pipes.ExtractPipe.createResults(ExtractPipe.scala:37) at org.neo4j.cypher.internal.pipes.ColumnFilterPipe.createResults(ColumnFilterPipe.scala:39) at org.neo4j.cypher.internal.pipes.EagerAggregationPipe.createResults(EagerAggregationPipe.scala:49) at org.neo4j.cypher.internal.pipes.ExtractPipe.createResults(ExtractPipe.scala:37) at org.neo4j.cypher.internal.pipes.ColumnFilterPipe.createResults(ColumnFilterPipe.scala:39) at org.neo4j.cypher.internal.executionplan.ExecutionPlanImpl$$anonfun$4$$anonfun$apply$2.apply(ExecutionPlanImpl.scala:95) at org.neo4j.cypher.internal.executionplan.ExecutionPlanImpl$$anonfun$4$$anonfun$apply$2.apply(ExecutionPlanImpl.scala:95) at org.neo4j.cypher.PipeExecutionResult.immutableResult(PipeExecutionResult.scala:37) at org.neo4j.cypher.PipeExecutionResult.iterator(PipeExecutionResult.scala:153) at org.neo4j.cypher.PipeExecutionResult.hasNext(PipeExecutionResult.scala:155) at scala.collection.Iterator$$anon$19.hasNext(Iterator.scala:334) at scala.collection.Iterator$$anon$19.hasNext(Iterator.scala:334) at scala.collection.Iterator$class.toString(Iterator.scala:1030) at scala.collection.Iterator$$anon$19.toString(Iterator.scala:333) at java.lang.String.valueOf(String.java:2826) at scala.collection.mutable.StringBuilder.append(StringBuilder.scala:185) at scala.collection.TraversableOnce$$anonfun$addString$1.apply(TraversableOnce.scala:287) at scala.collection.Iterator$class.foreach(Iterator.scala:660) at scala.Product$$anon$1.foreach(Product.scala:38) at scala.collection.TraversableOnce$class.addString(TraversableOnce.scala:285) at scala.Product$$anon$1.addString(Product.scala:38) at scala.collection.TraversableOnce$class.mkString(TraversableOnce.scala:263) at scala.Product$$anon$1.mkString(Product.scala:38) at scala.runtime.ScalaRunTime$._toString(ScalaRunTime.scala:175) at scala.collection.JavaConversions$IteratorWrapper.toString(JavaConversions.scala:561) at java.lang.String.valueOf(String.java:2826) at java.io.PrintStream.println(PrintStream.java:771)

Also, things like System.out.println(result.columns()) work fine and I can execute everything perfectly from the console... What's going on?

EDIT:

The query seems to return too fast, is there anything that I should do 'to make java wait' for a full response?

seems to be odd. what do you get if you execute the query in pure cypher console (via weadmin for example)? — ulkas

Michael Hunger Michael Hunger · Accepted Answer · 2012-12-16T21:16:36

Don't do that!

Use new RestCypherQueryEngine(restGraphDb.getRestAPI()) instead, otherwise all your queries are run on the client and each database access goes over the network.

And make sure to use parameters in your queries.

Use:

QueryResult<Map<String, Object>> query(String statement, Map<String, Object> params)

UnsupportedOperationException while executing Cypher Query in Java to Neo4j Server

2 Answers