在Hibernate中保持一对一关系实体-实体已分离

Question

我有两张一对一的表：

用户：

create table users (

  id int not null primary key,
  username varchar2(40) not null unique,
  password varchar2(60) not null,
  firstName varchar2(40) not null,
  lastName varchar2(40) not null,
  personalId varchar2(11) unique,
  city varchar2(40),
  address varchar2(40),
  email varchar2(40) not null unique,
  phone varchar2(9) unique
);

用户数

    create table usersAccounts (
  id int primary key,
  accountNr varchar2(26) not null unique,
  balance float not null,
  createDate date not null,
  expiredDate date,
  lastCharge date,
  userId int constraint userAccount_fk_user references users(id),
);

我的实体：

使用者

    @Entity
@Table(name = "users")
public class User implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue
    @Column(name = "id")
    private Integer id;
    @NotBlank
    @NotNull
    @Size(min = 3, max = 40)
    @Column(name = "username")
    private String username;
    @NotBlank
    @NotNull
    @Size(min = 3, max = 60)
    @Column(name = "password")
    private String password;
    @NotBlank
    @NotNull
    @Size(min = 3, max = 40)
    @Column(name = "firstName")
    private String firstName;
    @NotBlank
    @NotNull
    @Size(min = 3, max = 40)
    @Column(name = "lastName")
    private String lastName;
    @Size(min = 11, max = 11)
    @Column(name = "personalId")
    private String personalId;
    @Size(max = 40)
    @Column(name = "city")
    private String city;
    @Size(max = 40)
    @Column(name = "address")
    private String address;
    @NotBlank
    @NotNull
    @Email
    @Size(max = 40)
    @Column(name = "email")
    private String email;
    @Size(min = 9, max = 9)
    @Column(name = "phone")
    private String phone;
    @OneToMany(mappedBy = "user", cascade = CascadeType.ALL, fetch = FetchType.EAGER)
    private Set<UserRole> userRoleSet;
    @OneToOne(mappedBy = "user")
    private UserAccount userAccount;

用户账户

    @Entity
@Table(name = "usersAccounts")
public class UserAccount implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue
    @Column(name = "id")
    private Integer id;
    @NotNull
    @Column(name = "accountNr")
    private String accountNr;
    @NotNull
    @Column(name = "balance")
    private float balance;
    @NotNull
    @Column(name = "createDate")
    private Date createDate;
    @Column(name = "expiredDate")
    private Date expiredDate;
    @Column(name = "lastCharge")
    private Date lastCharge;
    @OneToOne(cascade = CascadeType.ALL)
    @JoinColumn(name = "userId")
    private User user;

我试图坚持这一点，但我有错误：

    @RequestMapping(value = "/admin/addAdmin", method = RequestMethod.POST)
public String addAdmin(@ModelAttribute("user") UserDto userDto,
        BindingResult result) {
    AddUserValidator addUserValidator = new AddUserValidator();
    addUserValidator.validate(userDto, result);
    if (result.hasErrors()) {
        return "admin/addadmin";
    } else {
        ErrorMessage errorMessage;
        User user = prepareModelUser(userDto);
        if ((errorMessage = userService.createUser(user)) != null) {
            result.rejectValue(errorMessage.getPath(),
                    errorMessage.getDescription());
            return "admin/addadmin";
        } else {
            user = userService.findByUsername(user.getUsername());
            UserRole userRole = new UserRole("ROLE_ADMIN");
            userRole.setUser(user);
            userRoleService.createUserRole(userRole);
            UserAccount ua = new UserAccount();
            ua.setAccountNr("12345678901");
            ua.setBalance(100);
            DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
            Date date = new Date();
            String dateStr = dateFormat.format(date);
            try {
                ua.setCreateDate(dateFormat.parse(dateStr));
            } catch (ParseException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            user = userService.findUser(user.getId());
            ua.setUser(user);
            userAccountService.createUserAccount(ua);
            return "redirect:/admin/adminlist";
        }
    }
}

当我尝试坚持我得到这个错误：

严重：Servlet。路径为[/ibank]的上下文中servlet[appServlet]的服务（）引发了异常[Request processing failed；嵌套异常为javax.persistence.PersistenceException:org.hibernate.PersistentObjectException:Distached entity传递给persistent:pl.piotr.ibank.model.User]，其根本原因为org。冬眠PersistentObjectException:传递给persist:pl.piotr的分离实体。ibank。模型使用者

userRole.setUser（user）； userRoleService.createUserRole（userRole）；保存良好，但当我尝试ua.setUser（user）； userAccount tService.createUserUser（ua）；我得到分离的实体

Answer 1

让主键同时成为外键是非常糟糕的做法。尤其是当上面有@GeneratedValue时。

仔细观察，您的实体映射正常，但需要调整usersAccounts表。从id列中删除外键约束，并添加新列userId，该列将是users#id的外键。之后一切都会好起来的。