Use Java property change listeners when object state changes need a conventional listener model without inventing a custom observer framework.
Java’s property change support is one of the most concrete Observer-style tools in the language ecosystem.
PropertyChangeListener gives a conventional way to publish:
That is useful in UI models and other object graphs where field-level changes matter.
Use it when:
Use something stronger when you need event routing, buffering, replay, backpressure, or cross-process messaging.