05_encapsulation_inheritance_polymorphism.md

05 — Encapsulation, Access modifiers, Inheritance, Polymorphism

Encapsulation

• Keep fields private and expose behavior via getters/setters.
• Access modifiers: public, private, protected.

Inheritance

• extends creates an "is-a" relationship. Use super() to call parent constructors.
• Overriding: subclass provides its own implementation of a superclass method.

Polymorphism

• Use a reference of the base class type to refer to subclass instances. Method calls use the runtime type (dynamic dispatch).

Example: OOPExample.java shows encapsulation, a base class Animal, a subclass Dog, overriding, and polymorphism.