code: public Connector getConnectorForSourceName( String sourceName ) {
          assert sourceName != null;
          return this.snapshot.get().getConnectorWithSourceKey(NodeKey.keyForSourceName(sourceName));
      }
docs: Returns a connector which was registered for the given source name.
  
  @param sourceName a {@code non-null} String; the name of a source
  @return either a {@link Connector} instance or {@code null}