addedRelations = new SimpleBufferAddedRelations();
concurrencyLevel = 1;
typeCache = new HashMap<String, Long>();
newVertexIndexEntries = new SimpleIndexCache();
} else {
addedRelations = new ConcurrentBufferAddedRelations();
concurrencyLevel = 1; //TODO: should we increase this?
typeCache = new NonBlockingHashMap<String, Long>();
newVertexIndexEntries = new ConcurrentIndexCache();
}