Spring Data Neo4j - Getting an exception when running a cypher query - spring

Question

I'm getting a strange exception when trying to run a simple cypher query. First i'll introduce my code, and then i'll show what cause the exception. So i have the following classes:
A simple class to represent a user profile:
public abstract class Profile extends AbstractEntity {
#Indexed
ProfileType profileType;
#Indexed(indexType = IndexType.FULLTEXT, indexName = "name")
String firstName;
#Indexed(indexType = IndexType.FULLTEXT, indexName = "name")
String lastName;
#Indexed
EyeColor eyeColor;
#Indexed
HairColor hairColor;
#Indexed
Nationality nationality;
#Indexed
int height;
public Profile() {
setProfileType();
}
public Profile(String firstName, String lastName, Nationality nationality, EyeColor eyeColor, HairColor hairColor, int height) {
this();
this.setFirstName(firstName);
this.setLastName(lastName);
this.setNationality(nationality);
this.setHairColor(hairColor);
this.setEyeColor(eyeColor);
this.setHeight(height);
}
/* Getters and Setters */
}
And a simple class, which inherit from Profile, and represents a civilian:
#NodeEntity
public class Civilian extends Profile {
#GraphProperty(propertyType = Long.class)
DateTime dateOfBirth;
#Indexed
boolean missing;
#RelatedTo
#Fetch
Set<Casualty> casualties = new HashSet<Casualty>(); //TODO: design
public Civilian() {
this.profileType = ProfileType.CIVILIAN;
}
public Civilian(String firstName, String lastName, Nationality nationality, EyeColor eyeColor, HairColor hairColor, int height, DateTime dateOfBirth, boolean missing) {
super(firstName, lastName, nationality, eyeColor, hairColor, height);
this.setDateOfBirth(dateOfBirth);
this.setMissing(missing);
}
/* Getters and Setters */
}
So i created the following repository for the Civilian class:
public interface CivilianRepository extends GraphRepository<Civilian> {
#Query("start n=node(*) where n.firstName=~{0} return n")
Page<Civilian> findCiviliansProperties(String firstName, Pageable page);
}
Ok. So i created few Civilian nodes, and populated the graph with them. There are no other nodes in the graph, except for the Civilian nodes. When i run the findCiviliansProperties method, i get the following exception:
Exception in thread "main" org.springframework.dao.InvalidDataAccessResourceUsageException: Error executing statement start n=node(*) where n.firstName=~{0} return n skip 0 limit 10; nested exception is org.springframework.dao.InvalidDataAccessResourceUsageException: Error executing statement start n=node(*) where n.firstName=~{0} return n skip 0 limit 10; nested exception is org.neo4j.cypher.EntityNotFoundException: The property 'firstName' does not exist on Node[0]
at org.springframework.data.neo4j.support.query.CypherQueryEngine.query(CypherQueryEngine.java:52)
at org.springframework.data.neo4j.repository.query.GraphRepositoryQuery.dispatchQuery(GraphRepositoryQuery.java:98)
at org.springframework.data.neo4j.repository.query.GraphRepositoryQuery.execute(GraphRepositoryQuery.java:81)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:312)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:96)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:260)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:94)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:155)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy33.findCiviliansProperties(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:198)
at com.sun.proxy.$Proxy36.findCiviliansProperties(Unknown Source)
at org.technion.socialrescue.playground.Playground.main(Playground.java:38)
Caused by: org.springframework.dao.InvalidDataAccessResourceUsageException: Error executing statement start n=node(*) where n.firstName=~{0} return n skip 0 limit 10; nested exception is org.neo4j.cypher.EntityNotFoundException: The property 'firstName' does not exist on Node[0]
at org.springframework.data.neo4j.support.query.CypherQueryEngine.parseAndExecuteQuery(CypherQueryEngine.java:63)
at org.springframework.data.neo4j.support.query.CypherQueryEngine.query(CypherQueryEngine.java:49)
... 20 more
Caused by: org.neo4j.cypher.EntityNotFoundException: The property 'firstName' does not exist on Node[0]
at org.neo4j.cypher.internal.commands.expressions.Property.apply(Property.scala:35)
at org.neo4j.cypher.internal.commands.expressions.Property.apply(Property.scala:29)
at org.neo4j.cypher.internal.commands.RegularExpression.isMatch(Predicate.scala:259)
at org.neo4j.cypher.internal.pipes.FilterPipe$$anonfun$createResults$1.apply(FilterPipe.scala:29)
at org.neo4j.cypher.internal.pipes.FilterPipe$$anonfun$createResults$1.apply(FilterPipe.scala:29)
at scala.collection.Iterator$$anon$22.hasNext(Iterator.scala:390)
at scala.collection.Iterator$$anon$19.hasNext(Iterator.scala:334)
at scala.collection.Iterator$class.isEmpty(Iterator.scala:272)
at scala.collection.Iterator$$anon$19.isEmpty(Iterator.scala:333)
at org.neo4j.cypher.internal.pipes.SlicePipe.createResults(SlicePipe.scala:32)
at org.neo4j.cypher.internal.pipes.ColumnFilterPipe.createResults(ColumnFilterPipe.scala:37)
at org.neo4j.cypher.internal.executionplan.ExecutionPlanImpl$$anonfun$6.apply(ExecutionPlanImpl.scala:127)
at org.neo4j.cypher.internal.executionplan.ExecutionPlanImpl$$anonfun$6.apply(ExecutionPlanImpl.scala:125)
at org.neo4j.cypher.internal.executionplan.ExecutionPlanImpl.execute(ExecutionPlanImpl.scala:33)
at org.neo4j.cypher.ExecutionEngine.execute(ExecutionEngine.scala:59)
at org.neo4j.cypher.ExecutionEngine.execute(ExecutionEngine.scala:63)
at org.neo4j.cypher.javacompat.ExecutionEngine.execute(ExecutionEngine.java:79)
at org.springframework.data.neo4j.support.query.CypherQueryEngine.parseAndExecuteQuery(CypherQueryEngine.java:61)
... 21 more
Caused by: org.neo4j.graphdb.NotFoundException: 'firstName' property not found for NodeImpl#0.
at org.neo4j.kernel.impl.core.Primitive.newPropertyNotFoundException(Primitive.java:184)
at org.neo4j.kernel.impl.core.Primitive.getProperty(Primitive.java:179)
at org.neo4j.kernel.impl.core.NodeImpl.getProperty(NodeImpl.java:52)
at org.neo4j.kernel.impl.core.NodeProxy.getProperty(NodeProxy.java:155)
at org.neo4j.cypher.internal.commands.expressions.Property.apply(Property.scala:33)
... 38 more
So the most important thing about this exception is the following line - The property 'firstName' does not exist on Node[0].. But how can it be? there are only Civilian nodes in the graph, and they all have the firstName property. Can it be that the neo4j framework adds some more hidden nodes to my graph which i'm not aware of? Because when i change my query into this:
start n=node(*) where has(n.firstName) AND n.firstName=~{0} return n
Everything works fine...
What is wrong?
Thanks!!

Answer 1

neo4j automatically comes with 1 node when you create a new instance, and that's the reference node. You should delete this.
graphDatabaseService.getNodeById(0).delete()