Java OOPS Concepts Tutorial & Interview Questions
By Bhau Automation • Java Interview Series
🎯 What You Will Learn
- What is Java?
- What is Object-Oriented Programming (OOP)?
- Four Pillars of OOP
- Java Inheritance Example
- Polymorphism with Examples
- Encapsulation and Abstraction
- Java Interview Questions
- Java for Selenium Automation
💡 Java OOPS concepts are the foundation of Selenium Automation Frameworks and are frequently asked in Java and Software Testing interviews.
📌 What is Java?
Java is a high-level, object-oriented programming language developed by Sun Microsystems (now Oracle). It is platform-independent because Java code runs on the Java Virtual Machine (JVM).
- Simple and Secure
- Platform Independent
- Object-Oriented
- Robust and Portable
- Widely used in Selenium Automation
📌 What is OOP?
Object-Oriented Programming (OOP) is a programming paradigm based on objects and classes. It improves code reusability, scalability and maintainability.
🚀 Four Pillars of OOP
| Concept | Description |
|---|---|
| Encapsulation | Wrapping data and methods together. |
| Inheritance | One class acquires properties of another class. |
| Polymorphism | One interface with multiple implementations. |
| Abstraction | Showing essential details while hiding implementation. |
💻 Java Inheritance Example
class Animal{
void sound(){
System.out.println("Animal Sound");
}
}
class Dog extends Animal{
void bark(){
System.out.println("Dog Barking");
}
}
public class Demo{
public static void main(String args[]){
Dog d = new Dog();
d.sound();
d.bark();
}
}
🎯 Why Java is Used in Selenium?
- Large Community Support
- Excellent IDE Support
- Easy Integration with TestNG
- Maven and Jenkins Compatibility
- Powerful OOP Features
- Rich Selenium Libraries
❓ Top Java OOPS Interview Questions
Q1. What are the four pillars of OOP?
Encapsulation, Inheritance, Polymorphism and Abstraction.
Q2. What is Polymorphism?
Polymorphism allows one method or interface to have multiple implementations.
Q3. What is Inheritance?
Inheritance allows a child class to reuse the properties and methods of a parent class.
Q4. What is Encapsulation?
Encapsulation binds data and methods into a single unit and protects data using access modifiers.
Q5. Why is Java preferred for Selenium?
Java provides stability, OOP support, framework compatibility and extensive community resources.
🎥 Watch Complete Tutorial
Watch Full Java OOPS Tutorial on YouTube
🔥 Key Takeaways
- Java is one of the most popular programming languages.
- OOP concepts are essential for Selenium Automation.
- Practice inheritance, polymorphism, encapsulation and abstraction.
- Java OOPS questions are frequently asked in interviews.
- Strong Java fundamentals help build robust automation frameworks.
⚡ Master Java OOPS Concepts to crack Java Developer, Selenium Automation and Software Testing interviews with confidence.
🚀 Created with ❤️ by Bhau Automation