Handling Keyboard Input with Scanner

To capture different data types from keyboard input in Java, use the Scanner class following these steps:

1. Import the Scanner class: import java.util.Scanner;
2. Create a Scanner object: Scanner input = new Scanner(System.in);
3. Use appropriate methods to read differnet data types:
   • input.next() for String
   • input.nextInt() for integer
   • input.nextDouble() for double
   • input.nextBoolean() for boolean
4. Close the scanner: input.close();

Example Implementation:

import java.util.Scanner;

public class UserInputExample {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        
        System.out.println("Welcome to our registration system!");
        System.out.print("Enter username: ");
        String username = input.next();

        System.out.print("Enter age: ");
        int age = input.nextInt();

        System.out.print("Enter weight: ");
        double weight = input.nextDouble();

        System.out.print("Are you single (true/false): ");
        boolean isSingle = input.nextBoolean();

        System.out.print("Enter gender (M/F): ");
        char gender = input.next().charAt(0);

        System.out.println("\nRegistration details:");
        System.out.println("Username: " + username);
        System.out.println("Age: " + age);
        System.out.println("Weight: " + weight);
        System.out.println("Single: " + isSingle);
        System.out.println("Gender: " + gender);
        
        input.close();
    }
}

Ganerating Random Numbers

To generate random numbers within a specific range:

1. Use Math.random() wich returns a double between 0.0 (inclusive) and 1.0 (exclusive)
2. For a range [a, b], use: (int)(Math.random() * (b - a + 1)) + a

Example Implementation:

public class RandomNumberGenerator {
    public static void main(String[] args) {
        // Generate random number between 1 and 6
        int diceRoll = (int)(Math.random() * 6) + 1;
        System.out.println("Dice roll: " + diceRoll);
        
        // Generate random number between 10 and 20
        int randomInRange = (int)(Math.random() * 11) + 10;
        System.out.println("Random between 10-20: " + randomInRange);
    }
}