code: protected GeometryEnvelope getEnvelope(GeoPackageGeometryData data) {
  		GeometryEnvelope envelope = null;
  		if (data != null) {
  			envelope = data.getOrBuildEnvelope();
  		}
  		return envelope;
  	}
docs: Get or build a geometry envelope from the Geometry Data
  
  @param data
  geometry data
  @return geometry envelope