OOP Intro

Object-Oriented Programming (OOP) is an approach that models a program after real-world objects. An object has data (attributes/fields) and behavior (methods). For example, a Student object can have data like name, age, and grade, along with behavior like study() and submitAssignment().

Java is a language built around OOP, with four core pillars.

• Encapsulation — controlling data and providing safe access to it

• Inheritance — a child class inheriting features from a parent class

• Polymorphism — letting one method behave differently depending on the object

• Abstraction — hiding unnecessary detail and showing only the important behavior

class Student {
  String name;

  void study() {
    System.out.println(name + " is studying Java.");
  }
}

public class Main {
  public static void main(String[] args) {
    Student student = new Student();
    student.name = "Aung";
    student.study();
  }
}

Student class is the blueprint. new Student() builds a Student object. The name field on the object gets set, and the study method gets called.

Aung is studying Java.