How to update 1.x addons to openHAB2?

I want to update some 1.x addons to the openHAB2/ESH API, so that they are fully integrated into openHAB2 (Paper UI, discovery, bridges…).
What’s the official way to do this?
Just create a new binding in openHAB2 and copy/paste the reusable code?
Thank you for the information