Visualize GeoPackage data on a GXY map

//First create the model
ILcdModelDecoder decoder =
    new TLcdCompositeModelDecoder(TLcdServiceLoader.getInstance(ILcdModelDecoder.class));
ILcdModel model = decoder.decode("Data/GeoPackage/states.gpkg");

//Create a layer for the model with default styling
ILcdGXYLayer layer = createGXYGeoPackageLayer(model);
//Wrap the layer with an async layer wrapper to ensure
//that the view remains responsive while data is being painted
layer = ILcdGXYAsynchronousLayerWrapper.create(layer);

//Add the async layer to the GXY view (an ILcdGXYView)
view.addGXYLayer(layer);

/**
 * A GeoPackage file can contain:
 * <ul>
 *   <li>one or more vector data sets</li>
 *   <li>one or more raster data sets</li>
 *   <li>one or more elevation data sets</li>
 *   <li>a mix of the above</li>
 * </ul>
 * This method can deal with all those scenarios
 */
static ILcdGXYLayer createGXYGeoPackageLayer(ILcdModel model) {
  //The model decoder returns a model tree node when the file contains multiple data sets
  //The node itself is just an empty container. We create an empty layer node for that container.
  //Then we loop over the child models (=the actual data), and create layers for those as well
  if (model instanceof ILcdModelContainer) {
    TLcdGXYLayerTreeNode node = new TLcdGXYLayerTreeNode(model);
    for (int i = 0; i < ((ILcdModelContainer) model).modelCount(); i++) {
      ILcdModel childModel = ((ILcdModelContainer) model).getModel(i);
      //Use recursion to create layers for the child models
      node.addLayer(createGXYGeoPackageLayer(childModel));
    }
    return node;
  } else if (model.getModelDescriptor() instanceof TLcdGeoPackageModelDescriptor) {
    //The TLcdGXYLayer.create method can deal with both raster and vector data,
    //so no need to check what the model contains
    //The class javadoc of TLcdGeoPackageModelDescriptor describes how to
    //discover whether the model contains vector or raster data

    return TLcdGXYLayer.create(model);
  }
  throw new IllegalArgumentException("Cannot create layer for model " + model);
}