# Add fields to the entities

Before mapping the entities to the database, you must add the necessary fields to each entity.

1. Add the following fields to the Employee entity:

       private Long id;
       private String firstNname;
       private String lastName;
       private String address;
       private List<PhoneNumber> phoneNumbers;
       private Long version;

2. Import java.util.List.

3. Generate Getters and Setters for each field.

4. Add the following fields to the Address entity:

       private Long id;
       private String street;
       private String city;
       private String stateOrProvince;
       private String country;
       private String postalCode;

5. Add the following fields to the PhoneNumber entity:

       private String type;
       private String areaCode;
       private String number;
       private Employee owner;

Next, you will Associate the entity with a database table.