Java OOP Fundamentals: Inheritance, Encapsulation, Polymorphism, Abstraction

🚀 Java Concepts Made Simple (Visual Notes) While learning Java, I created my own notes to understand concepts like: • JVM & JRE • Platform Independent Programming • Classes & Objects • Variables & Data Types • Naming Conventions • Type Casting Later I enhanced these notes using AI to make them cleaner and more readable, so anyone starting with Java can understand them easily. Swipe through the slides to explore the concepts 📚 If you are learning Java, save this post for revision. Anshika Sinha Sonam Yadav Roshani Kumari #java #programming #coding #javadeveloper #learnjava #computerscience #codingjourney

🚀 Day 12/45 – Understanding Constructors in Java On Day 12 of my Java learning journey, I explored the concept of Constructors, which play an important role in object initialization. Constructors are automatically called when an object is created and help in assigning initial values to object properties. 📚 What I Learned Today Today I learned: ✔ What constructors are and how they work ✔ Difference between constructors and methods ✔ Default constructors ✔ Parameterized constructors for initializing values 💻 Practice Work To apply my learning, I implemented: • A program using a default constructor • A program using a parameterized constructor • Creating multiple objects with different values 🎯 Key Takeaway Constructors make object creation more efficient and organized by initializing data at the time of object creation. This concept is very important for building structured and scalable applications. Learning OOP step by step is making programming more interesting. #Java #Programming #LearningInPublic #CodingJourney #SoftwareDevelopment #OOP

🚀 Java Learning Journey – Day 5 Why Java Says "No" to Multiple Inheritance (and "Yes" to Interfaces) 💎 Ever wondered why Java doesn't allow a class to inherit from two parents? It all comes down to the Diamond Problem. When two parent classes have the same method, the compiler gets confused: "Which one should I use?" To keep things clean and prevent bugs, Java blocks this at the class level. But wait—you can still achieve the same goal! 💡 By using Interfaces, you get the flexibility of multiple inheritance without the ambiguity. Check out this quick visual guide I put together to break it down. 👇 #Java #Programming #ObjectOrientedProgramming #SoftwareDevelopment #CodingTips #TechCommunity

Day 8 of My Java Learning Journey ☕💻 Today I continued strengthening my core Java fundamentals and focused on understanding Method Overloading and basic Inheritance concepts. What I practiced today: • Implemented method overloading by creating an Area Calculator for Square, Rectangle, and Circle • Learned how Java decides which method to call at compile time (Compile-Time Polymorphism) • Practiced taking user input using the Scanner class • Explored the basics of Inheritance using parent and child classes • Understood how child classes can access methods from parent classes One key takeaway today: Writing small programs helps reinforce concepts much better than just reading theory. Next on the learning roadmap: • Method Overriding • Runtime Polymorphism • Deeper understanding of Object-Oriented Programming in Java Step by step, building stronger backend fundamentals. #Java #LearningInPublic #Programming #BackendDevelopment #100DaysOfCode #JavaDeveloper

Day 9 – Java Learning Journey Today I continued strengthening my Java fundamentals, focusing on method overriding and important rules in inheritance. Key concepts I explored: • Method Overriding Rules in Java The child class method must have the same method signature as the parent class method. The return type must be the same or covariant (a subclass of the parent return type). The method cannot be static, because static methods belong to the class rather than the object. • Covariant Return Types Java allows a child class method to return a more specific type than the parent class method, making inheritance more flexible. • Static vs Instance Methods I also learned why static methods cannot be overridden and are instead method hidden, which behaves differently from runtime polymorphism. Step by step, continuing to build a stronger foundation in Core Java and OOP concepts. 🚀 #Java #CoreJava #OOP #MethodOverriding #Programming #SoftwareDevelopment #LearningJourney

🚀 Implementing the Basics of OOP in Java Today, I practiced the fundamental concepts of Object-Oriented Programming (OOP) in Java 💻 • Created a "Car" class as a blueprint • Defined attributes: model, color, and price • Created multiple objects in the Main class • Accessed object properties using the dot (.) operator • Modified object data to understand independent object states 💡 Key Takeaways: • A class is a blueprint for creating objects • An object is an instance of a class • Each object maintains its own separate copy of instance variables • Changing one object does not affect another object This small implementation helped me clearly understand how objects manage their own state in memory. Step by step, strengthening my foundation in Java and OOP 🚀 #Java #OOP #Programming #CodingJourney #Learning #SoftwareDevelopment

🚀 Day 4 of My Java Learning Journey Today I learned how a Java program works internally and covered some important core concepts. 📌 Topics I Covered: 🔹 How to run a Java program • Compile using javac • Run using java • JVM executes the program 🔹 Main Method in Java public static void main(String[] args) • public → JVM can access it from anywhere • static → No need to create object • void → Does not return any value • main → Entry point of program 🔹 System.out.println() • System → class from java.lang package • out → object of PrintStream • println() → method used to print output 🔹 Variables in Java • A variable is a container to store data in memory (RAM) • Syntax: datatype variable_name = value; Example: int age = 35; System.out.println("The age is: " + age); 📌 Rules of Variables • Cannot contain spaces • Cannot start with a digit • Can use _ and $ symbols Building strong fundamentals in Java step by step and staying consistent every day. You can check my code here 👇 🔗 https://lnkd.in/gDP4A9r6 If you are also learning Java, let’s connect and grow together 🤝 #Java #JavaDeveloper #CodingJourney #Programming #LearningInPublic #SoftwareDevelopment

Day 28 -What I Learned in a Day(JAVA) Today I started learning Looping Statements in Java. Loops are used to execute a block of code repeatedly until a certain condition becomes false. They help reduce code repetition and make programs more efficient. In Java, there are mainly three types of loops: • while loop • do-while loop • for loop Today I focused on the while loop. 🔹 What is a While Loop? A while loop executes a block of code repeatedly as long as the condition is true. The condition is checked before the loop executes, so if the condition is false initially, the loop will not run. Syntax of While Loop: initialization; while(condition) { // statements increment / decrement; } What I Practiced Today: ✔ Practiced 3 basic while loop programs ✔ Built a calculator program using while loop and switch statement ✔ Learned how loops control program flow and reduce repetitive code Every day I’m taking small steps to improve my Java programming skills and strengthen my understanding of core concepts. Practiced 👇 #Java #JavaLearning #Programming #CodingJourney #Loops #WhileLoop

While studying object oriented programming in Java, access modifiers explain how data and methods can be accessed from different places in a program. They help control visibility and protect the internal structure of classes. Things that became clear : • access modifiers define where a variable or method can be accessed • private members are accessible only inside the same class • default members are accessible within the same package • protected members are accessible within the same package and also in subclasses • public members can be accessed from anywhere These access levels help control how different parts of a program interact with each other. A simple structure shows how access modifiers appear in code : class Example { private int a; int b; protected int c; public int d; } Using the correct access level helps maintain better control over data and keeps the program structure organized. #java #oop #programming #learning #dsajourney

☕ Java Output Methods Explained – print() vs println() vs \n When learning Java programming, understanding how output works is very important. In the example program, three different output methods are used: 📌 What happens here? ✔ println() → Prints the text and moves the cursor to the next line ✔ print() → Prints the text but stays on the same line ✔ \n → Creates a manual line break (newline character) 💡 Output of this program: Hello World! Hello JishanHii Jishan Because print() does not move to the next line, the second and third outputs appear on the same line. Understanding these small details is essential when learning Java fundamentals and writing clean console output. 🚀 Every Java developer starts with simple programs like this before building large applications. 👉 Question for developers: Do you prefer using println() or \n for line breaks in Java? #Java #JavaProgramming #Coding #Programming #SoftwareDevelopment #BackendDevelopment #JavaDeveloper #LearnJava #ComputerScience #CodingTips