1. Fix 1 bug: Throw null pointer exception when reading data after the reader reaches the end of file, so should return directly when `_do_lazy_read` read no data. 2. Optimize code: Remove unused parameters. 3. Fix regression test
1. Fix 1 bug: Throw null pointer exception when reading data after the reader reaches the end of file, so should return directly when `_do_lazy_read` read no data. 2. Optimize code: Remove unused parameters. 3. Fix regression test