Geek2Geek NoSQL

Join the next Geek2Geek in Berlin this Friday night. We will talk about NoSQL databases and have talks to Neo4J, CouchDB and ArangoDB.


The MeetUp will happen at CO.UP in Kreuzberg. Which is a pretty cool coworking space.

Locafox, a young StartUp from Berlin, will sponsor pizza & beer. They are currently hiring in all areas. Check out their job listings here: And many thanks for the pizza. We really appreciate that.

JRuby + Neo4J Problems

I have JRuby on Rails app, which is using an ueber JAR to access Neo4J. The Neo4J database is in the rails root directory unter “data/”. By starting the HTTP Server I got today this Exception:

IllegalArgumentException: No index provider 'lucene' found. Maybe the intended provider (or one more of its dependencies) aren't on the classpath or it failed to load.

The problem was in the “data/”. In some way it was corrupt. I am not sure. After I exchanged the “data/” directory with an older version, the HTTP Server started without any problems.

JRuby + Spring + AspectJ + Neo4J

I am playing around with JRuby and Neo4j as Graph Engine. My set up on the backend side contains a Java Application with Spring Annotations, AspectJ and Neo4J. In the frontend I have a Rails App with JRuby.

Any time I try to access a class that have an annotation like “@NodeEntity”, I get an Exception. It seems that Spring and AspectJ is to much in this chain. I should get rid of Spring and AspectJ.