Introduced with the Java 17 release, pattern matching enhances the instanceof operator so Java developers can better check and object's type and extract its components, and more efficiently deal with ...

Java SE 14 (March 2020) introduced a limited form of pattern matching as a preview feature, which becomes a permanent feature in Java SE 16 (March 2021).

The Observable design pattern is found in many Java APIs and in reactive programming. Here's an introduction to the timeless Observable pattern in Java.