Increase the regularity of the code

[Adamyuanyuan]

To increase the regularity of the code:

1. it is recommended to remove all @author and @Date at the top of the class; remove all author and date at the top of the class #759
2. clean up Unused import at the top of the class; Clean up Unused import from the top of the class #758

[wushengyeyouya]

LGTM.

[Adamyuanyuan]

Thanks

[peacewong]

LGTM.