Use ListenerHandles // nipafx

Keeping references to both a listener and its observable in order to later remove the listener is a common but problematic pattern in Java (and OOP generally). It clutters code, introduces invariants that are easy to break, invites unintended usage, causes code duplication, and can introduce race conditions. The ListenerHandle abstraction — a simple interface with attach() and detach() methods — encapsulates this complexity cleanly. LibFX provides a ready-made Java implementation covering JavaFX observable/listener combinations, a utility class, and a builder for custom combinations. Reactive programming libraries like ReactiveX and ReactFX are also mentioned as alternatives.