Interface QueryRouter

  • public interface QueryRouter
    An interface used by Queries to route themselves to an appropriate QueryEngine. As of 1.2 QueryRouter only supports routing by DataMap.
    • Method Detail

      • route

        void route​(QueryEngine engine,
                   Query query,
                   Query substitutedQuery)
        A callback method that allows a query to set its preferred engine during the routing phase. It allows query to further customize its routing, e.g. it is possible to implement query chains that pass multiple queries for execution.
        engine - engine to use for query execution
        query - A query to execute.
        substitutedQuery - a query that was substituted for "query". Results must be mapped back to substituted query.
      • engineForName

        QueryEngine engineForName​(String name)
        Returns a QueryEngine for a given name. If the name is null, a default QueryEngine is returned. If there's no default engine, an exception is thrown.