Sealed classes make Java an even more powerful and expressive language and set the stage for even more sophisticated techniques such as pattern matching, which we'll explore in a subsequent article. A ...

A factory interface replaces the abstract factory class (Optional), Every factory method is responsible for creating an object and injecting its dependencies. Consider a simple example below: ...

With connection pooling, the JMS factory classes typically have proxies (configured by an administrator) so the open() and close() requests actually go to the proxies that manage a connection pool.