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IMPORTANT CONCEPTS IN JAVA SERIES

Java Concepts — Object Oriented Programming I

Explanations, Examples, Codes and Diagrams

This series on Must Know Java Concepts will introduce all the important Java Concepts.

1. Java Features & JDK
2. Fundamentals & OOPS ← we are here
3. Generics
4. Collections
5. Exception Handling
6. Files & Input-Output
7. Serialization
8. Multithreading
9. Synchronization
10. Networking
11. All 50 Java Keywords

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Fundamentals & Object Oriented Programming

Object-Oriented Programming is a methodology or paradigm to design a program using classes and objects. It simplifies the software development and maintenance. Main Concepts — Inheritance, Polymorphism, Abstraction, Encapsulation.

Data Types in Java

NOTE : UTF-8 is the most popular Unicode character encoding with 90% websites using it.

Data Type Promotion in Java :

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Wrapper Classes in Java

Operators in Java

Java Naming Conventions :

Object vs Class

Constructors vs Methods

Types of Inheritance (Supported through Class)

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Types of Inheritance (Supported through Interface only)

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Association vs Aggregation vs Composition

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Aggregation vs Composition

NOTE : The “final” keyword is used in Composition to ensure the child variable is initialized.

Polymorphism — Method Overloading vs Method Overriding

Abstract Class vs Interface

Java Access Modifiers

Abstraction vs Encapsulation

Methods of Object Class

The Object class is the parent class of all the classes in Java by default.

Congrats! 🎉 We are one step closer to “becoming a Java Expert” now!!

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This article is supposed to serve as a beginner’s guide for OOPS.

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