code: private List<ODocument> getEdgesBetweenModels(String source, String target) {
          ODocument from = getModel(source);
          ODocument to = getModel(target);
          String query = "select from E where out = ? AND in = ?";
          return graph.query(new OSQLSynchQuery<ODocument>(query), from, to);
      }
docs: Returns all edges which start at the source model and end in the target model.