import java.util.Scanner; // Needed to read user input
 
 public class Reservations {
 
  // Boolean array for seating [false = available, true = taken]
  static boolean[][] seats;
 
  // Main method
  public static void main(String[] args) {
 
  // Initiates all array values to be false (available)
  seats = new boolean[4][4];
  for (int i = 0; i < 4; i++) {
  for (int j = 0; j < 4; j++) {
  seats[i][j] = false;
  }
 
  // Welcome message
  System.out.println("-------------------------");
  System.out.println("Welcome to NSCC AirLines.");
  System.out.println("-------------------------\n");
 
  // Starts program
  start();
  }
  }
 
  public static void start() {
 
  // Scanner needed to read users input
  Scanner sc = new Scanner(System.in);
 
  // Variables for user input
  String requestedSection;
  String requestedSeat;
 
  // Counters for seating array
  int countSection = 0;
  int countSeat = 0;
 
  // Prompts the user to select their choice of section
  System.out.print("Please type 1 for First Class or 2 for Economy: ");
 
  // Section preference
  requestedSection = sc.nextLine();
 
  switch (requestedSection) {
  case "1":
  // User selects first class
  System.out.println(">>> You have selected First Class. \n");
  break;
 
  case "2":
  // User selects economy
  System.out.println(">>> You have selected Economy. \n");
  break;
 
  default:
  // User has not selected a valid class
  System.out
  .println(">>> You have not selected a valid class. Please try again. \n");
  start();
  break;
  }
 
  // Prompts the user to select their choice of seat
  System.out.print("Please type 1 for window and 2 for aisle: ");
 
  // Seat preference
  requestedSeat = sc.nextLine();
 
  switch (requestedSeat) {
  case "1":
  // User selects first class
  System.out.println(">>> You have selected a window seat. \n");
  break;
 
  case "2":
  // User selects economy
  System.out.println(">>> You have selected an aisle seat. \n");
  break;
 
  default:
  // User has not selected a valid class
  System.out.println(">>> You have not selected a valid seat. Please try again. \n");
  start();
  break;
  }
 
  // Closes Scanner
  sc.close();
  }
 }

Exception in thread "main" java.util.NoSuchElementException: No line found at java.util.Scanner.nextLine(Unknown Source) at Reservations.start(Reservations.java:50) at Reservations.main(Reservations.java:29)