getting java.sql.SQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails

Question

I'm working on a javafx+hibernate project where I have a Company entity which has a list of users. I have a class NaturalPerson which extends abstract class User. I made a registration window on my javafx app and when I'm trying to register a NaturalPerson I get:

`java.sql.SQLIntegrityConstraintViolationException: Cannot add or update a child row: a foreign key constraint fails.`
(`companyhibernate`.`naturalperson`, CONSTRAINT `FK_s5c7plmyohwfq5biwepwg8dqa` FOREIGN KEY (`id`) REFERENCES `company` (`companyName`))

I'm very new to hibernate and can't figure out how to fix this. Could someone help?

User.java:

@Entity
@Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
public abstract class User implements Serializable {
    @Id @GeneratedValue(strategy = GenerationType.TABLE)
    private Long id;
    protected String name;
    protected String loginName;
    protected String password;
    @ManyToOne
    private Company company;


    public User() {
    }

    public User(String name, String loginName, String password, Company company) {
        this.name = name;
        this.loginName = loginName;
        this.password = password;
        this.company = company;
    }

NaturalPerson.java

@Entity
public class NaturalPerson extends User implements Serializable {

    private String surname;
    private String phoneNumber;
    private String email;
    @ManyToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE},
            mappedBy = "responsibleUsers")
    @OrderBy("id ASC")
    @LazyCollection(LazyCollectionOption.FALSE)
    private List<Category> responsibleForCategories;
    @ManyToOne
    private Company company;

    public NaturalPerson() {
    }

    public NaturalPerson(String name, String loginName, String password, String surname, String phoneNumber, String email, List<Category> responsibleForCategories, Company company) {
        super(name, loginName, password, company);
        this.surname = surname;
        this.phoneNumber = phoneNumber;
        this.email = email;
        this.responsibleForCategories = responsibleForCategories;

    }

Company.java

@Entity
public class Company implements Serializable {

    @Id
    private String companyName;
    private String compEmail;
    private String compPhoneNum;
    @OneToMany(mappedBy = "company", cascade= CascadeType.ALL, orphanRemoval=true)
    @OrderBy("id ASC")
    @LazyCollection(LazyCollectionOption.FALSE)
    private List<Category> allCategories;
    @OneToMany(mappedBy = "company", cascade= CascadeType.ALL, orphanRemoval=true)
    @OrderBy("id ASC")
    @LazyCollection(LazyCollectionOption.FALSE)
    private List<User> allUsers;


    public Company() {
    }

    public Company(String companyName, String compEmail, String compPhoneNum, ArrayList<Category> allCategories, ArrayList<User> allUsers) {
        this.companyName = companyName;
        this.compEmail = compEmail;
        this.compPhoneNum = compPhoneNum;
        this.allCategories = allCategories;
        this.allUsers = allUsers;
    }

NaturalPersonRegistration.java

public class NaturalPersonRegistration implements Initializable {
@FXML
public TextField nameField;
@FXML
public TextField surnameField;
@FXML
public TextField phoneNumField;
@FXML
public TextField emailField;
@FXML
public TextField usernameField;
@FXML
public PasswordField passwordField;
@FXML
public Button signUpButton;

private Company company;

EntityManagerFactory factory = Persistence.createEntityManagerFactory("CompanyHibernate");
CompanyHibernateControl companyHibernateControl = new CompanyHibernateControl(factory);
UserHibernateControl userHibernateControl = new UserHibernateControl(factory);

public void setCompany(Company company) {
    this.company = company;
}

public void createUser(ActionEvent actionEvent) throws Exception {
    company = companyHibernateControl.findCompany(company.getCompanyName());
    List<Category> responsibleForCategories = new ArrayList<Category>();
    User user = new NaturalPerson(nameField.getText(),
            usernameField.getText(),
            passwordField.getText(),
            surnameField.getText(),
            phoneNumField.getText(),
            emailField.getText(),
            responsibleForCategories,
            company
    );
    userHibernateControl.create(user);
    loadMainWindow();
}

Answer 1

Have you checked during registration that

company = companyHibernateControl.findCompany(company.getCompanyName());

returned non-empty value?