code: public static <E> ReadableSource<E> asSource(URI uri, Class<E> type) {
      return new DatasetSourceTarget<E>(uri, type);
    }
docs: Expose the {@link View} or {@link Dataset} represented by the URI
  as a Crunch {@link ReadableSource}.
  
  @param uri the URI of the view or dataset to read from
  @param type    the Java type of the entities in the dataset
  @param <E>     the type of entity produced by the source
  @return a {@link ReadableSource} for the view
  
  @since 0.15.0