Access Google My Business APIs w/ simple login

I'd like a proof of concept implementation that uses ONLY simple Google account login (username + password) or SSO to access My Business APIs. (Must be a Google account with associated Google My Business) Requirements - Java or Scala implementation - Can be a console application, but must include instructions. AC: - User signs in to Google using ONLY simple Google account login (username + password) or SSO programatically. - Once user is logged in (using method from above), get listing of all reviews for businesses linked to the logged in user programatically.