ClassNotFoundException: com.thinkaurelius.titan.diskstorage.es.ElasticSearchIndex

[jordi-chacon]

Hi,

I am trying to configure DynamoDB Local as backend for my Titan database. Up until now I have been using BerkeleyDB.

My build.gradle file looks like this:

plugins {
  id 'groovy'
  id 'com.github.johnrengelman.shadow' version '1.2.1'
  id 'net.saliman.cobertura' version '2.2.7'
}

archivesBaseName = '....'
apply plugin: 'groovy'

repositories {
    mavenCentral()
    jcenter()
    flatDir {
        dirs 'lib'
    }
    maven {
        url "https://jitpack.io"
    }
    maven {
        url "http://dynamodb-local.s3-website-us-west-2.amazonaws.com/release"
    }
}

dependencies {
    compile 'org.codehaus.groovy:groovy-all:2.4.5'
    compile 'commons-configuration:commons-configuration:1.10'
    compile 'com.thinkaurelius.titan:titan-core:1.0.0'
    compile 'com.thinkaurelius.titan:titan-berkeleyje:1.0.0'
    compile 'com.amazonaws:dynamodb-titan100-storage-backend:1.0.0'
    compile 'com.amazonaws:aws-java-sdk-dynamodb:1.10.45'
    compile 'com.amazonaws:DynamoDBLocal:1.10.20'
    compile fileTree(dir: 'lib', include: ['*.jar'])
    testCompile "org.spockframework:spock-core:1.0-groovy-2.4"
    testRuntime 'org.objenesis:objenesis:2.2'
    testRuntime "com.github.cglib.cglib:cglib-nodep:5503bcca74"
}

I configure my Graph instance like this: TitanFactory.open("dynamodblocal.properties") where that properties file is basically this file (https://github.com/awslabs/dynamodb-titan-storage-backend/blob/1.0.0/src/test/resources/dynamodb-local.properties) except that I have removed the last 5 lines related to index search.

I do not want to perform any index search and thus I do not want ElasticSearch, that is why I have removed the last 5 lines of the properties file.

When I run my application, an exception is thrown when opening the properties file:

java.lang.IllegalArgumentException: Could not find implementation class: com.thinkaurelius.titan.diskstorage.es.ElasticSearchIndex
        at com.thinkaurelius.titan.util.system.ConfigurationUtil.instantiate(ConfigurationUtil.java:47)
        at com.thinkaurelius.titan.diskstorage.Backend.getImplementationClass(Backend.java:473)
        at com.thinkaurelius.titan.diskstorage.Backend.getIndexes(Backend.java:460)
        at com.thinkaurelius.titan.diskstorage.Backend.<init>(Backend.java:147)
        at com.thinkaurelius.titan.graphdb.configuration.GraphDatabaseConfiguration.getBackend(GraphDatabaseConfiguration.java:1805)
        at com.thinkaurelius.titan.graphdb.database.StandardTitanGraph.<init>(StandardTitanGraph.java:123)
        at com.thinkaurelius.titan.core.TitanFactory.open(TitanFactory.java:94)
        at com.thinkaurelius.titan.core.TitanFactory.open(TitanFactory.java:62)
        at com.....Titan.getInstance(Titan.groovy:63)
        at com.....node.Control.<init>(Control.groovy:25)
        at com.....node.ControlSpec.$spock_initializeFields(ControlSpec.groovy:34)

        Caused by:
        java.lang.ClassNotFoundException: com.thinkaurelius.titan.diskstorage.es.ElasticSearchIndex
            at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
            at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
            at java.lang.Class.forName(Class.java:264)
            at com.thinkaurelius.titan.util.system.ConfigurationUtil.instantiate(ConfigurationUtil.java:42)

I do not understand why the ElasticSearchIndex class is fetched, since I have not specified it anywhere.

Just to verify that this doesn't have to do with my code, I have changed the properties file to the following:

storage.backend=berkeleyje
storage.directory=/tmp/foo

And this works just fine.

I can avoid the exception by adding titan-es to my build.gradle file, but I would like to avoid that as I am not using ElasticSearch.

Any ideas how I can avoid including titan-es in my project?
Thanks!

[amcp]

Is it possible you opened the graph once with the es properties included, and then deleted them afterwards? Or, Is it enough to just open a fresh new graph without the Es lines to get this error?

[jordi-chacon]

You are correct Alexander!
Restarting DynamoDBLocal did the trick. Now I can run my project without the titan-es dependency.
Thank you!