runtime error

解析app时发生了报错，而且这个app好像也没有被加壳

Traceback (most recent call last):
  File "literadar.py", line 256, in <module>
    res = lrd.compare()
  File "literadar.py", line 236, in compare
    self.analyse()
  File "literadar.py", line 231, in analyse
    self.extract_dex()
  File "literadar.py", line 209, in extract_dex
    if class_name[0] is not 'L':
IndexError: string index out of range