code: private VectorServerLayer searchLayer(MapPresenter mapPresenter, String layerId) {
  		if (layerId != null) {
  			for (int i = 0; i < mapPresenter.getLayersModel().getLayerCount(); i++) {
  				Layer layer = mapPresenter.getLayersModel().getLayer(i);
  				if (layer instanceof VectorServerLayer) {
  					VectorServerLayer serverLayer = (VectorServerLayer) layer;
  					if (layerId.equals(serverLayer.getServerLayerId())) {
  						return (VectorServerLayer) layer;
  					}
  				}
  			}
  		}
  		return null;
  	}
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