Question

create a menu in Java. A menu is a presentation of options for you to select. The article above that is in our discussion board may be helpful.

You can do this in the main() method.

1. Create a String variable named menuChoice.

2. Display 3 options for your program. I recommend using 3 System.out.println statements and a 4th System.out.print to show "Enter your Selection:". This needs to be inside the do -- while loop.

       A. Buy Stock.
       B. Sell Stock
       X. Exit

       Enter your Selection:

3. Prompt for the value menuChoice.

4. If menuChoice is "A", display "Buy Stock" and redisplay the menu.

If menuChoice is "B", display "Sell Stock" and redisplay the menu.

If menuChoice is "X", the loop needs to terminate.

If any other choice is given, display "Invalid selection" and redisplay the menu.

For grading, I will test with uppercase characters. Review section 5.1 for String comparisons.

Convert the menuChoice to an upper case String after input or as part of the input but before any processing is done. This will allow me to enter 'a' but process as 'A'. You can Google for "Java string uppercase" to see how this is done.

For Task 4 - Create 2 void methods - 1 for option A to call, and another for option B to call. Do the display work only inside these methods and call these methods for these options.

Answer 1

Following line of code is implementation of the above problem.

Two color are used here:

Black is for the actual code and

Strong Cyan is for comments.

import java.util.Scanner;                                             // importing scanner class
public class MenuChoice {

   void display_A()        //method for displaying choice A
   {
       System.out.println("\nBuy Stock\n");                             // "\n" is used for newline
   }

   void display_B()                                                            //method for displaying choice B
   {
       System.out.println("\nSell Stock\n");                             // "\n" is used for newline
   }
  
    public static void main(String[] args) {
      
      Scanner input = new Scanner(System.in);                 // Scanner class for input taking
    
      String menuChoice;
    
      MenuChoice disp = new MenuChoice();                   // creating object of MenuChoice class
    
      do
      {
       System.out.println("A. Buy Stock");
       System.out.println("B. Sell Stock");
       System.out.println("X. Exit");
       System.out.println("\nEnter your Selection:");    // "\n" is used for newline
     
       menuChoice = input.nextLine();    // taking input from keyboard
     
       menuChoice = menuChoice.toUpperCase();                     // to make UPPERCASE if it is in lowercase
     
       switch(menuChoice)                       // switch-case started from here
       {
           case "A":
               disp.display_A();                    // calling option A
               break;
             
           case "B":
               disp.display_B();                  // calling option B
               break;
             
           case "X":
               System.out.println("Exiting... Thank You!\n");
               System.exit(0);   // for program termination
               break;
             
           default:
               System.out.println("\nInvalid Selection\n");
               break;
       }

      }while(true);
    }
  
}