converting to the same class while comparing (equals(Obj)) & Adding a final class

1.) Converted 'success' and 'error' to String class while comparing it with another string while applying equals(Obj).

2.) Added a final class instead of implementing a constant interface.
Hi !

I have tried cloning the repository to use it locally and apply squash to merge these commits into one. But it has been failing consistently.
Can I just use github via browser for editing files and pushing them ?