Chapter - 4 Mathematical Functions, Characters and Strings Study the REVEL textbook section 4.5.2 Case Study : Converting a Hexadecimal digit to a Decimal digit. For Project - 4: Write a program that convert a Binary string to a Decimal number.

Part - 1 : Use Case Study 4.5.2 as an example.

Part - 2 : Write a program to convert a Binary string to a Decimal number.

Using the Scanner class, the user input should be a Binary string.

The program should validate the input as a valid Binary number.

If not valid, display a message and the program should end. If valid, continue.

The output should display the corresponding Decimal number.

Ensure that the Java code works on Replit.

import java.util.Scanner; 2 3 public class HexDigit2Dec { 4 public static void main(String[] args) { 5 Scanner input = new Scanner(System.in); 6 System.out.print("Enter a hex digit: "); 7 String hexString = input.nextLine(); 8 9 // Check if the hex string has exactly one character 10 if (hexString.length() != 1) { 11 System.out.println("You must enter exactly one character"); 12 System.exit(1); 13 } 14 15 // Display decimal value for the hex digit 16 char ch = Character.toUpperCase(hexString.charAt(0)); 17 if ('A'   4.5.2 Case Study: Converting a Hexadecimal Digit to a Decimal Value The hexadecimal number system has 16 digits: 09,AF. The letters A, B, C, D, E, and F correspond to the decimal numbers 10, 11,12,13,14, and 15 . We now write a program that prompts the user to enter a hex digit and display its corresponding decimal value, as given in CodeAnimation 4.4