Thanks for your advice.

Basically, I don't like multiple `if | else if` too. But like L176 (`t.getMode() == Node.Mode.NORMAL`) and L180 (`t.getMode() == Node.Mode.EXCLUSIVE`) in new code, sometimes I use multiple conditions when the conditions are parallel. It is easier to find structure.

But I also understand what you want to say. So I try to think and refactor to find this PR more easily.