title: nioNeoDbPersistence turned null
body: <p>I am using neo4j as a backend, I started to have a weird error (see below). After looking up on neo4j@googlegouprs.com I figured out that may be I'm trying to use a DB that has been shutdown. Since I'm pretty sure that my code is not executing any shutdown() instruction I just disabled the shutdownHook(), yet, nothing happens. Someone please has an idea about what is happening or (and) a clue how to solve it.  </p>
  
  <p>Thank you in advance </p>
  
  <pre><code>java.lang.NullPointerException 
  at org.neo4j.kernel.impl.nioneo.xa.NioNeoDbPersistenceSource.createReadOnlyResourceConnection(NioNeoDbPersistenceSource.java:96) 
  at org.neo4j.kernel.impl.persistence.PersistenceManager.getReadOnlyResource(PersistenceManager.java:222) 
  at org.neo4j.kernel.impl.persistence.PersistenceManager.getReadOnlyResourceIfPossible(PersistenceManager.java:245) 
  at org.neo4j.kernel.impl.persistence.PersistenceManager.loadLightNode(PersistenceManager.java:73) 
  at org.neo4j.kernel.impl.core.NodeManager.getNodeByIdOrNull(NodeManager.java:308)
  at org.neo4j.kernel.impl.core.NodeManager.getNodeById(NodeManager.java:325) 
  at org.neo4j.kernel.InternalAbstractGraphDatabase.getNodeById(InternalAbstractGraphDatabase.java:912)
  </code></pre>