JSONB pojo with immutable fields

Employee.java

package org.example;

import java.util.UUID;
import javax.json.bind.annotation.JsonbCreator;
import javax.json.bind.annotation.JsonbProperty;

public final class Employee {

    private final String id;
    private final String firstName;
    private final String lastName;
    private final String email;
    private final String phone;
    private final String birthDate;
    private final String title;
    private final String department;

    private Employee(String id, String firstName, String lastName,
            String email, String phone, String birthDate,
            String title, String department) {

        this.id = id;
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
        this.phone = phone;
        this.birthDate = birthDate;
        this.title = title;
        this.department = department;
    }

    @JsonbCreator
    public static Employee of(
            @JsonbProperty("firstName") String firstName,
            @JsonbProperty("lastName") String lastName,
            @JsonbProperty("email") String email,
            @JsonbProperty("phone") String phone,
            @JsonbProperty("birthDate") String birthDate,
            @JsonbProperty("title") String title,
            @JsonbProperty("department") String department) {

        return new Employee(UUID.randomUUID().toString(), firstName,
                lastName, email, phone, birthDate, title, department);
    }

    public String getId() {
        return this.id;
    }

    public String getFirstName() {
        return this.firstName;
    }

    public String getLastName() {
        return this.lastName;
    }

    public String getEmail() {
        return this.email;
    }

    public String getPhone() {
        return this.phone;
    }

    public String getBirthDate() {
        return this.birthDate;
    }

    public String getTitle() {
        return this.title;
    }

    public String getDepartment() {
        return this.department;
    }

    @Override
    public String toString() {
        return "Employee{" + "id=" + id
                + ", firstName=" + firstName
                + ", lastName=" + lastName
                + ", email=" + email
                + ", phone=" + phone
                + ", birthDate=" + birthDate
                + ", title=" + title
                + ", department=" + department
                + '}';
    }
}