Java Object-Oriented Programming
Java is an object-oriented programming (OOP) language, which means it is based on the concept of objects and classes. OOP in Java helps organize code efficiently, promotes code reuse, and makes software easier to maintain. Here’s a quick overview of the key OOP principles in Java.
Java Classes and Objects
A class is a blueprint for creating objects, which are instances of a class. Classes define the properties (variables) and behaviors (methods) that the objects will have. Objects are used to access and manipulate data within the program.
Java Inheritance
Inheritance allows one class (the child or subclass) to inherit the fields and methods of another class (the parent or superclass). This promotes code reuse and establishes a natural hierarchy between classes.
Java Polymorphism
Polymorphism means "many forms" and allows a method to perform different tasks based on the object that is invoking it. Polymorphism in Java is achieved through method overriding (runtime) and method overloading (compile-time).
Java Encapsulation
Encapsulation is the concept of wrapping data (variables) and methods together as a single unit, often achieved by marking variables as private
and providing public
getters and setters. This ensures that sensitive data is hidden and protected from external modification.
Java Abstraction
Abstraction is the process of hiding complex implementation details and showing only the essential features of an object. In Java, abstraction is achieved through abstract classes and interfaces, which allow developers to define methods that subclasses must implement.
Static and Final Keywords
- The
static
keyword allows variables and methods to belong to the class itself rather than to any specific instance of the class. - The
final
keyword is used to create constants and prevent classes from being subclassed or methods from being overridden.