Prev Next

Java If...Else: Real-Life Examples

Understanding how to use if...else statements in real-world scenarios can help solidify the concept. Below are examples demonstrating practical applications.

1. Age Verification

A program that checks if a user is old enough to vote.

import java.util.Scanner;

public class AgeVerification {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter your age: ");
        int age = scanner.nextInt();
        if (age >= 18) {
            System.out.println("You are eligible to vote.");
        } else {
            System.out.println("You are not eligible to vote.");
        }
        scanner.close();
    }
}

Output:

Enter your age: 20 You are eligible to vote.

2. Simple Login System

A program that checks user credentials.

import java.util.Scanner;

public class LoginSystem {
    public static void main(String[] args) {
        String username = "admin";
        String password = "password123";
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter username: ");
        String inputUsername = scanner.nextLine();
        System.out.print("Enter password: ");
        String inputPassword = scanner.nextLine();

        if (inputUsername.equals(username) && inputPassword.equals(password)) {
            System.out.println("Login successful.");
        } else {
            System.out.println("Invalid credentials.");
        }
        scanner.close();
    }
}

Output:

Enter username: admin Enter password: password123 Login successful.

3. Grading System

A program that assigns grades based on marks.

import java.util.Scanner;

public class GradingSystem {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter your marks: ");
        int marks = scanner.nextInt();

        if (marks >= 90) {
            System.out.println("Grade A");
        } else if (marks >= 80) {
            System.out.println("Grade B");
        } else if (marks >= 70) {
            System.out.println("Grade C");
        } else if (marks >= 60) {
            System.out.println("Grade D");
        } else {
            System.out.println("Grade F");
        }
        scanner.close();
    }
}

Output:

Enter your marks: 85 Grade B

Key Takeaways

  • if...else statements are essential for decision-making in applications.
  • They can be used in various scenarios like authentication, data validation, and conditional operations.
  • Understanding practical examples helps in applying the concept effectively.
Prev Next