All Classes and Interfaces

Class	Description
AbstractAnimal	Abstract base class combining shared state, a concrete default method, and an abstract method subclasses must implement.
Animal	Base class exposing an overridable speak() method.
Cat	Animal subclass that overrides speak() to meow.
Dog	Animal subclass that overrides speak() to bark.
DogWithDefault	Concrete AbstractAnimal that implements the required speak() method.
InterfaceCat	ISpeaker implementation that meows.
InterfaceDog	ISpeaker implementation that barks.
ISingleSpeaker	Interface contract for a single, non-substitutable speaker.
ISpeaker	Interface contract for anything that can speak.
Part1_InheritancePolymorphism	Demonstrates inheritance-based polymorphism resolved via the JVM's per-class virtual method table (vtable).
Part2_InheritanceWithDefaults	Demonstrates inheritance-based polymorphism where a concrete default method is inherited unchanged alongside an abstract method that must be overridden.
Part3_InterfacePolymorphism	Demonstrates interface-based polymorphism resolved via the JVM's itable (interface method table) rather than a class vtable.
Part4_InterfaceMonomorphism	Demonstrates monomorphic dispatch: because PureBreedDog is final, the JIT can devirtualize the call and invoke speak() directly, without an itable/vtable lookup.
PureBreedDog	Sealed 'final' class ensures NO other subclass can modify this method path.