Java Design Patterns
Design patterns are reusable solutions to common programming problems. They’re not code you copy and paste, but templates for structuring […]
OOP
Build a To-Do List App
A to-do list is the classic intermediate project. It combines everything you’ve learned so far: collections to store tasks, file
How to Prepare for a Java Technical Interview
Technical interviews test more than your Java knowledge. They assess how you think through problems, communicate your reasoning, and handle
OOP Interview Questions in Java with Answers
Object-oriented programming questions dominate Java interviews. Interviewers use them to gauge whether you understand core concepts or just memorized syntax.
Abstract Classes in Java
Interfaces define pure contracts with no implementation. Regular classes provide complete implementations. Abstract classes sit in between. They can define
Java Interfaces
Java allows only single inheritance. A class can extend one parent. But what if a class needs capabilities from multiple
Java Encapsulation
So far, you’ve accessed object fields directly. Set a dog’s name with dog.name = "Buddy". Read a car’s mileage with
Java Polymorphism
Inheritance lets child classes override parent methods. Polymorphism takes this further. It lets you write code that works with a
Java Inheritance
Classes often share common characteristics. Dogs, cats, and birds are all animals. Cars, motorcycles, and trucks are all vehicles. Inheritance
Java Constructors
In the previous tutorial, you created objects and then set their fields one by one. That approach works but has
Java Classes and Objects
The previous tutorial introduced object-oriented concepts. Now you’ll put them into practice. By the end of this tutorial, you’ll create
Introduction to Object-Oriented Programming
So far, you’ve written programs using variables, methods, and data structures. That approach works for small programs. But as projects