static void mainScreen() {
        System.out.println("\n\nWelcome to Point Based Loyalty System Client\n");
        System.out.println("Please enter your options");
        System.out.println("1: Add customer");
        System.out.println("2: Delete customer");
        System.out.println("3: Add merchant");
        System.out.println("4: Delete merchant");
        System.out.println("5: Add Reward Type");
        System.out.println("6: Delete Reward Type");
        System.out.println("7: Associate reward type with merchant");
        System.out.println("8: Add a redemption");
        System.out.println("9: Claim redemption");
        int choice = Console.getInt("choice");
        switch (choice) {
            case 1:
                System.out.println("Enter a customer detail");
                Main.doAddCustomer();
                break;
            case 2:
                System.out.println("Provide a customer id to delete");
                Main.doDeleteCustomer();
                break;
            case 3:
                System.out.println("Enter a merchant detail");
                Main.doAddMerchant();
                break;
            case 4:
                System.out.println("Enter a merchant id to delete");
                Main.doDeleteMerchant();
                break;
            case 5:
                System.out.println("Add reward type");
                Main.doAddRewardType();
                break;
            case 6:
                System.out.println("Delete reward type");
                Main.doDeleteRewardType();
                break;
            case 7:
                System.out.println("Associate reward type");
                Main.doAssocRewardType();
                break;
            case 8:
                System.out.println("Add a redemption");
                Main.doAddRedemption();
                break;
            case 9:
                System.out.println("Claim a redemption");
                Main.doClaimRedemption();
                break;
            default:
                System.out.println("You have entered an invalid option");
        }
    }