neo4j enterprise 1.8.1 Cypher ExecuteEngine bug? - grails

Question

I am running neo4j enterprise 1.8 on grails and wanted to upgrade to 1.8.1. As I am also using the Cypher Engine extensively, after upgrade I tried to execute some queries. Unfortunately I encountered an Exception when trying to initiate the Cypher ExecutionEngine.
I've written a small Service which does the work for me:
import org.neo4j.cypher.javacompat.ExecutionEngine
import org.neo4j.kernel.impl.util.StringLogger
class CypherService {
def graphDatabaseService
static transactional = true
def executeString(String cypherString) {
log.debug "start method executeString"
ExecutionEngine executionEngine = new ExecutionEngine(graphDatabaseService, StringLogger.DEV_NULL)
if(executionEngine) {
def result = executionEngine.execute(cypherString)
return result
} else {
log.error "Could not initialize the execution engine for Cypher"
return null
}
}
}
When initiating the Execution Engine, I got the following Exception:
java.lang.NoSuchMethodError: com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap$Builder.maximumWeightedCapacity(J)Lcom/googlecode/concurrentlinkedhashmap/ConcurrentLinkedHashMap$Builder;
at org.neo4j.cypher.internal.LRUCache.<init>(LRUCache.scala:31)
at org.neo4j.cypher.ExecutionEngine$$anon$1.<init>(ExecutionEngine.scala:91)
at org.neo4j.cypher.ExecutionEngine.<init>(ExecutionEngine.scala:91)
at org.neo4j.cypher.javacompat.ExecutionEngine.<init>(ExecutionEngine.java:54)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at org.codehaus.groovy.reflection.CachedConstructor.invoke(CachedConstructor.java:77)
at org.codehaus.groovy.runtime.callsite.ConstructorSite$ConstructorSiteNoUnwrapNoCoerce.callConstructor(ConstructorSite.java:102)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallConstructor(CallSiteArray.java:52)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:190)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:202)
at com.netjay.fanorakel.CypherService.executeString(CypherService.groovy:16)
Any idea what is going wrong here, and is there a solution to avoid this?
Best
Michael

Answer 1

You could probably also just rebuild Neo4j's cypher module against the older version of the lib, or actually exclude the dependency from neo4j.

Answer 2

I had the same issue- with 1.8.1 I needed to separately include concurrentlinkedhashmap-lru.1.3.1.jar
http://code.google.com/p/concurrentlinkedhashmap/downloads/detail?name=concurrentlinkedhashmap-lru-1.3.1.jar&can=2&q=

Answer 3

The problem here is that:
Neo4j 1.8.1 introduced a new dependency to concurrentlinkedhashmap_lru version 1.3.1, AND
Grails has a dependency to concurrentlinkedhashmap_lru version 1.2_jdk5, AND
concurrentlinkedhashmap_lru's API is not backwards compatible for these two versions.
Therefore the grails codebase has been recently upgraded to move the dependency to 1.3.1, see https://github.com/SpringSource/grails-data-mapping/commit/b15e207a2a08ac16e77de399733cb9cc14eff48e and
https://github.com/grails/grails-core/commit/6dfab1a5db4da8c176351f23d65c7fc0d4aa6364.
So to use Neo4j 1.8.1 (and newer) with Grails you could either wait for a new Grails release or build a Grails snaptshot on your own.