Over the years, I have been part of several IT recruitment panels and have interacted with numerous candidates
during campus drives and technical interviews. From my experience, I can confidently say that most interviewers
look beyond your marks or how many programs you can memorize. What truly matters is your
clarity of thought, sound understanding of fundamentals, and the
ability to write efficient, logical code.
My sincere suggestion is — don’t just memorize; understand the concepts, visualize how they work, and
learn to apply them in real-world scenarios. Infosys, like most reputed IT organizations, values
candidates who think clearly, learn continuously, and can collaborate effectively in team settings.
“Preparation is not about doing everything — it’s about doing the right things with focus, depth, and
confidence.”
📚 The Three Pillars of Preparation
Data Structures & Algorithms (DSA): Build logical thinking and problem-solving ability.
Java Programming: Master OOP principles and write clean, efficient code.
Computer Networks & Operating Systems: Strengthen your conceptual foundation.
☕ Core Java Interview Questions
Benefits include Modularity, Encapsulation, Inheritance, Polymorphism, Abstraction, Maintainability, and
Real-world Modeling.
Example – Modularity
class MathUtils {
public int add(int a, int b) { return a + b; }
}
MathUtils util = new MathUtils();
System.out.println(util.add(5, 10)); // 15
Example – Encapsulation
class BankAccount {
private double balance;
public void deposit(double amount) { balance += amount; }
public double getBalance() { return balance; }
}
Example – Inheritance
class Vehicle { void start() { System.out.println("Vehicle starts"); } }
class Car extends Vehicle { void honk() { System.out.println("Car honks"); } }
Car c = new Car();
c.start(); c.honk();
A final variable is a constant whose value cannot change once assigned. For references, the reference remains
fixed, but the object state can change.
A constructor is a special method used to initialize objects. It has the same name as the class and no return
type.
Constructor name = class name; Method name differs.