Answer Happy

Why do I keep getting this error message:
The method Menu() is undefined for the type ASG4Media
public static boolean Menu() { System.out.println(""); System.out.println("Media Rental System"); System.out.println("1. Add "); System.out.println("2. Find "); System.out.println("3. Remove "); System.out.println("4. Rent "); System.out.println("5. Modify "); System.out.println("6. Display One Media Object "); System.out.println("7. Display All Media of One Type"); System.out.println("8. Display Whole Library of MediaObjects "); System.out.println("9. Exit "); return true; }} // end Menu
public static void main(String[] args) throws Exception {
//instance of manager Manager manager = new Manager();
// load media data from file manager.loadMediaFromFile(); System.out.println("Media List: ");
// title System.out.println("ID\tRent\tType\tTitle\t\t\tPub\tScope\tCalc");
manager.displayCurrentMedia();
// ArrayList to hold the media library ArrayList<Media> media = new ArrayList<>();
Scanner input = new Scanner(System.in); // scanner
// loop until exit while (Menu()) { int choice = 0; System.out.print("Enter your selection: "); choice = Integer.parseInt(input.nextLine());
switch (choice) { case 1: manager.addMedia(); break;
case 2: System.out.print("Enter media id to find: "); int idMedia =Integer.parseInt(input.nextLine()); manager.findMedia(idMedia); break;
case 3: System.out.print("Enter media id to remove: "); int id = Integer.parseInt(input.nextLine()); manager.remove(id); break;
case 4: System.out.print("Enter media id to rent: "); int idRentMedia =Integer.parseInt(input.nextLine()); manager.rentMedia(idRentMedia); break;
case 5: System.out.print("Enter media id to modify: "); int mediaIdModify =Integer.parseInt(input.nextLine()); manager.modifyMedia(mediaIdModify); break;
case 6: System.out.println(""); System.out.println("\tChoose Display type: "); System.out.println("\t1. Display all items"); System.out.println("\t2. Display one item"); System.out.println("\t3. Display all selections of atype(Ebook, MovieDVD, MusicCD)"); System.out.print("Enter your selection: "); int displayChoice =Integer.parseInt(input.nextLine());
// loop to display a specific media category switch (displayChoice) {
case 1: manager.displayCurrentMedia(); break;
case 2: System.out.print("Enter media id: "); int displayId =Integer.parseInt(input.nextLine()); manager.displayOneMedia(displayId); break;
case 3: System.out.println(""); System.out.println("\t\tChoose Display Item :"); System.out.println("\t\t1. Ebook"); System.out.println("\t\t2. MovieDVD"); System.out.println("\t\t3. MusicCD"); System.out.print("\t\tEnter your selection: "); int itemChoice =Integer.parseInt(input.nextLine());
// loop to display specific media type switch (itemChoice) { case 1: manager.displayEbook(); break;
case 2: manager.displayMovieDVD(); break;
case 3: manager.displayMusicCD(); break;
default: System.out.println("Invalid choice."); break; } break;
default: System.out.println("Invalid choice."); break; } break;
case 7: System.out.println("Thank you for using the program.Goodbye!"); System.exit(0); break;
default: System.out.println("Enter valid choice."); break; } } input.close();}}