private static ClasspathEntryModel readClasspathEntry(IonReader reader) {
    if (reader.next() == null) return null;
    reader.stepIn();
    ClasspathEntryModel entryModel = new ClasspathEntryModelImpl(
      readFileSet(reader, null),
      readFileSet(reader, null),
      readFileSet(reader, null)
    );
    reader.stepOut();
    return entryModel;
  }
private static ClasspathEntryModel readClasspathEntry(IonReader reader)