Introduction to Object-Oriented Programming in Java

What is Object-Oriented Programming (OOP)?

• Object-Oriented Programming: Treats everything as objects.
• Real-world analogy: Objects like pens, mice, and remotes.
  • Pen:
    • Properties: color, height, type, brand
    • Behavior: Writing
  • Remote:
    • Properties: height, color, number of buttons
    • Behavior: Turning on AC

Key Concepts in Java OOP

1. Objects

   • Has properties (attributes) and behaviors (methods).
   • Example:
     • Human: Knows how to talk, walk, dance (properties), and performs these actions (behaviors).

2. Classes

   • Blueprint for objects.
   • Defines properties and behaviors.
   • Example: A class defines the structure/properties of a table, just like a carpenter's blueprint.

Implementing OOP in Java

• Everything in Java is done using objects.
• Mindset: Think in terms of objects even for simple tasks, like adding two numbers.
• To create objects in Java, we first need classes.

Creating Classes and Objects

Why We Need Objects and Classes

• Everything in real life and programming relies on objects.
• Objects are created based on the details provided in their class definitions.

Real-World Analogy for Class and Object Creation

• Table Example:
  • Carpenter creates a table based on the given technical details (blueprint).
  • Java's analogy: Class file is the blueprint.
  • Middle Person: Translates general requirements into technical details.

JVM and Object Creation

• JVM (Java Virtual Machine): Responsible for creating objects based on class files.
• Class file compilation:
  1. Create a class file as a blueprint.
  2. Compile it to create byte code.
  3. JVM uses byte code to create the object.

Next Steps

• How to create classes.
• How to create objects from those classes.