Is it possible for an anonymous inner class to extend a class and
implement an interface, or for it to implement two or more interfaces?
The only way an anonymous inner class can both extend a class and
implement an interface is when it implicitly extends the Object class
and is instantiated as an interface, or when it extends a class that already
implements an interface.
The only way an anonymous inner class can implement two or more interfaces is if it is extending a class that already implements those interfaces. In other words, when you instantiate an anonymous class, only one interface or class name may follow the new keyword. Therefore, an anonymous inner class may only explicitly extend a single class or implement a single interface.