首页 > 解决方案 > 用户注册后,Hibernate 在角色表中添加了不必要的行

问题描述

我正在尝试通过用户注册向我的 webapp 添加功能。Webapp 基于 spring boot、hibernate 和 mysql 数据库,前端是 angular。通常,用户创建过程正常工作,用户数据通过 json 正确地从前端发送到后端并保存到 shop_user 表中的数据库中(包括所有用户数据,如姓名、姓氏、地址等),但它没有'T 有角色栏。

我也有表“角色”,应该是:

id     name
1      USER
2      ADMIN

并加入表 user_role,它由表 shop_user 中的 user_id 和表 role 中的角色 id 组成,所以它应该如下所示:

id_user    id_role
1          2
2          1
3          1

在网站上创建用户时,默认将角色设置为 USER 是硬编码的。这似乎工作得很好,因为它在 shop_user 中添加了一个新行,并在 user_role 中添加了一行,但是......它还在“角色”表中创建了一个新行。

所以最后'角色'表看起来像这样:

id     name
1      ADMIN
2      USER
3      USER
4      USER
5      USER
99     USER

`

虽然这不是阻止应用程序工作的阻塞错误,但不幸的是,它不是“应该工作”......因为表应该只包含两个角色行(将来可能还有其他角色行),但不能相乘为每个用户!

这是用户的有缺陷的代码:

用户

@Entity
@Table(name = "shop_user")
public class User extends AbstractEntity {

@Column
private String firstName;

@Column
private String lastName;

@Column
private String addressLine;

@Column
private String city;

@Column
private String country;

@Column
private String zipCode;

@Column
private String phoneNumber;

@Column
private String email;

@Column
private String password;

@ManyToMany(cascade = CascadeType.ALL,  fetch = FetchType.EAGER)
@JoinTable(name = "user_role",
        joinColumns = @JoinColumn(name = "id_user", referencedColumnName = "id"),
        inverseJoinColumns = @JoinColumn(name = "id_role", referencedColumnName = "id"),
        uniqueConstraints = {@UniqueConstraint(columnNames = {"id_user", "id_role"})})
private List<Role> roles;

public User() {
}

public User(User user) {
    setId(user.getId());
    this.firstName = user.getFirstName();
    this.lastName = user.getLastName();
    this.addressLine = user.getAddressLine();
    this.city = user.getCity();
    this.country = user.getCountry();
    this.zipCode = user.getZipCode();
    this.phoneNumber = user.getPhoneNumber();
    this.email = user.getEmail();
    this.password = user.getPassword();
    this.roles= user.getRoles();
}

public List<Role> getRoles() {
    return roles;
}

public void setRoles(List<Role> roles) {
    this.roles = roles;
}

public String getFirstName() {
    return firstName;
}

public void setFirstName(String firstName) {
    this.firstName = firstName;
}

public String getLastName() {
    return lastName;
}

public void setLastName(String lastName) {
    this.lastName = lastName;
}

public String getAddressLine() {
    return addressLine;
}

public void setAddressLine(String addressLine) {
    this.addressLine = addressLine;
}

public String getCity() {
    return city;
}

public void setCity(String city) {
    this.city = city;
}

public String getCountry() {
    return country;
}

public void setCountry(String country) {
    this.country = country;
}

public String getZipCode() {
    return zipCode;
}

public void setZipCode(String zipCode) {
    this.zipCode = zipCode;
}

public String getPhoneNumber() {
    return phoneNumber;
}

public void setPhoneNumber(String phoneNumber) {
    this.phoneNumber = phoneNumber;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}
}

角色实现:

角色

@Entity
@Table(name = "role")
public class Role extends AbstractEntity {

    @Column
    private String name;

    @ManyToMany(mappedBy = "roles", cascade = CascadeType.PERSIST)
    private List<User> users;

    public Role(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public List<User> getUsers() {
        return users;
    }

    public void setUsers(List<User> users) {
        this.users = users;
    }
}

抽象实体:

抽象实体

@MappedSuperclass
public abstract class AbstractEntity implements Persistable<Long> {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    public void setId(Long id) {
        this.id = id;
    }

    @Override
    public Long getId() {
        return id;
    }

    @Override
    public boolean isNew() {
        return id == null;
    }
}

用户服务:

用户服务实现

@Service
public class UserServiceImpl extends AbstractServiceImpl<User, UserDTO> implements UserService {

    private final UserRepository userRepository;
    private final UserConverter userConverter;

    public UserServiceImpl(UserRepository userRepository, UserConverter 
userConverter) {
        this.userRepository = userRepository;
        this.userConverter = userConverter;
    }

    @Override
    protected JpaRepository<User, Long> getRepository() {
        return userRepository;
    }

    @Override
    protected Converter<User, UserDTO> getConverter() {
        return userConverter;
    }

    @Override
    @Transactional
    public User registerUser(User user) {
        List<Role> roles = new LinkedList<>();
        roles.add(new Role("USER"));
        user.setRoles(roles);
        return userRepository.save(user);
    }}

我几乎可以肯定这涉及到 Hibernate 和对象创建中的关系映射,但不能完全弄清楚......

任何帮助将不胜感激,谢谢!

标签: javamysqlhibernatespring-boot

解决方案


问题在这里:

@Override
@Transactional
public User registerUser(User user) {
    List<Role> roles = new LinkedList<>();
    roles.add(new Role("USER"));
    user.setRoles(roles);
    return userRepository.save(user);
}}

由于关系 User -> Role 是级联持久化的,因此(新)角色new Role("USER")也会持久化,并且您最终会为每个用户创建一个新角色,而不是重用现有角色。

解决方案是检查名称 = USER 的角色是否存在。如果不存在,则插入它。否则将现有的添加到roles集合中。


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