code: private void setMapTypeInMap() {
          if (getInitialized()) {
              final String mapTypeName = getMapType().toString();
              if (logger.isDebugEnabled()) {
                  logger.debug("setting map type in OpenLayers map: {}", mapTypeName);
              }
              bingMapsApiKey.ifPresent(apiKey -> jsMapView.call("setBingMapsApiKey", apiKey));
              wmsParam.ifPresent(wmsParam -> {
                  jsMapView.call("newWMSParams");
                  jsMapView.call("setWMSParamsUrl", wmsParam.getUrl());
                  wmsParam.getParams().forEach((key, value) -> jsMapView.call("addWMSParamsParams", key, value));
              });
              xyzParam.ifPresent(xyzParam -> {
                  jsMapView.call("setXYZParams", xyzParam.toJSON());
              });
              jsMapView.call("setMapType", mapTypeName);
          }
      }
docs: sets the value of the mapType property in the OL map.