This is creating the service layer and domain layer. Nothing else. 
An Overview. Upper right hand of the HomeScreenUI.java there is a Log In button. The person will log in and then have a choice to add / update or delete the items on the menu
Below, is my envision for the MainItems table (not this assignment)

ID, MenuType, MenuName, MenuDescription
1, Appetizer, Ahi Sashimi, Ahi Sashimi
2, Appetizer, Salmon Sashimi, Salmon Sashimi
3, Appetizer, Bay Shrimp Coctail, Bay Shrimp Coctail
4, Appetizer, Medium Shrimp Coctail, Medium Shrimp Coctail
5, MainMenu, Salads, SALADS
Grilled fish served over fresh mixed greens, cucumbers, red onion, carrots, tomatoes and capers. Choose from our homemade dressings bleu cheese, ranch, thousand islands or vinaigrette. Fish is at least a 6-ounce portion
6, MainMenu, Sandwiches, SANDWICHES
Served on a soft bolillo roll with fresh chopped lettuce, red onion, tomatoes and homemade tartar sauce, toasted upon request. 
7, MainMenu, Taco, TACO
Served on fresh corn tortillas with cabbage, tomatoes, onions, cheddar cheese, our homemade white sauce and your choice fish, marinated in our spicy chipotle. 
8, Beverages, Coke, Non-Alcoholic
9, Beverages, Diet Coke, Non-Alcoholic
10, Beverages, Root Beer, Non-Alcoholic
11, Beverages, Dr. Pepper, Non-Alcoholic
12, Beverages, Sprite, Non-Alcoholic
13, Beverages, Cucumber Martini, Alcoholic
14, Beverages, Pineapple Drop, Alcoholic
15, Beverages, Raspberry Drop, Alcoholic

Here is my envision for the MenuSubItems:
1, Red Snapper Salad, Salads
2, Scallop Salad, Salads
3, Jumbo Shrimp Salad, Salads
4, Mahi Mahi Salad, Salads
5, Red Snapper Sandwiches, Sandwiches
6, Scallop Sandwiches, Sandwiches
7, Jumbo Shrimp Sandwiches, Sandwiches
8, Mahi Mahi Sandwiches, Sandwiches
9, Red Snapper Taco, Taco
10, Scallop Taco, Taco
11, Jumbo Shrimp Taco, Taco
12, Mahi Mahi Taco, Taco