So here's the scenario you have a JSON Object that contains a list of objects. Each one of the objects in the primary JSON Object also contain a list of objects. So for demonstration purposes we will use a car with a list of seats and each seat has a list of buckles (Car -> Seats -> Buckles). Completely random example, yes I know.
So if you have the use case where you don't want to deserialize any seats that don't have buckles this is how you can do it using a Custom GSON Deserializer.