It would be a little more cumbersome to write, but the same effect can be achieved easily:

  A a = new A();
  try {
      B(a);
      return C(a);
  } finally {
      a.cleanup();
  }
 

Transforms into:

  Either<Exception, Result> ret;
  
  A a = new A();

  ret = B(a);
  if (ret.isRight()) ret = C(a);
  
  a.cleanup();
  return ret;

Maybe someone can rewrite this even more cleanly. I can think of an easy-to-generate improvement containing a GOTO.