code: private FeatureShape getFeatureShape(Map<Long, FeatureShape> featureIds, long featureId) {
  
          FeatureShape featureShape = featureIds.get(featureId);
          if (featureShape == null) {
              featureShape = new FeatureShape(featureId);
              featureIds.put(featureId, featureShape);
          }
          return featureShape;
      }
docs: Get the map shapes for the feature ids and feature id
  
  @param featureIds feature ids
  @param featureId  feature id
  @return feature shape