@ManyToMany org.hibernate.MappingException

Question

I'm struggling with Java Spring Hibernate, I'm trying to implement Oauth2 and I keep getting an error while connecting table User to Roles through @ManyToMany. I have read all the answers available referencing my problem and no matter what I try I still get a org.hibernate.MappingException.

Below are the full details of what I'm trying to do.

Database Structure

CREATE TABLE IF NOT EXISTS `role` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=latin1;

INSERT INTO `role` (`id`, `name`) VALUES
(1, 'ROLE_USER'),
(2, 'ROLE_ADMIN'),
(3, 'ROLE_GUEST');

-- --------------------------------------------------------

CREATE TABLE IF NOT EXISTS `user` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `email` varchar(255) NOT NULL,
  `nickname` varchar(255) NOT NULL,
  `password` varchar(255) NOT NULL,
  PRIMARY KEY (`id`),
  UNIQUE KEY `user_email_uindex` (`email`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1;


INSERT INTO `user` (`id`, `email`, `nickname`, `password`) VALUES
(1, 'test@test.com', 'Admin', 'test');

-- --------------------------------------------------------

--
-- Table structure for table `user_role`
--

DROP TABLE IF EXISTS `user_role`;
CREATE TABLE IF NOT EXISTS `user_role` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `email` varchar(255) NOT NULL,
  `role_id` int(11) NOT NULL,
  PRIMARY KEY (`id`),
  KEY `email_fk` (`email`),
  KEY `role_fk` (`role_id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=latin1;

--
-- Dumping data for table `user_role`
--

INSERT INTO `user_role` (`id`, `email`, `role_id`) VALUES
(1, 'test@test.com', 1),
(2, 'test@test.com', 2);

========================================

Roles.java

@Entity
public class Role implements GrantedAuthority {

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @NotBlank
    private String name;

    @JsonIgnore
    @ManyToMany(mappedBy = "roles")
    private Set<User> users = new HashSet<>();

    @Override
    public String getAuthority() {
        return name;
    }

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

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

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

User.java

@Entity
@Table(name = "user")
public class User {
    private Integer id;
    private String email;
    private String password;
    private String nickname;

    @JsonIgnore
    @ManyToMany(fetch = FetchType.EAGER)
    @JoinTable(name = "user_role",
            joinColumns = { @JoinColumn(name = "email") },
            inverseJoinColumns = { @JoinColumn(name = "role_id") })
    private Set<Role> roles = new HashSet<>();

    public User(User user) {
        super();
        this.id = user.getId();
        this.email = user.getEmail();
        this.password = user.getPassword();
        this.nickname = user.getNickname();
        this.roles = user.getRoles();
    }

    public User() {
    }

    @Id
    @Column(name = "id", nullable = false)
    public Integer getId() {
        return id;
    }

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

    @Basic
    @Column(name = "email", nullable = false, length = 255)
    public String getEmail() {
        return email;
    }

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

    @Basic
    @Column(name = "password", nullable = false, length = 255)
    public String getPassword() {
        return password;
    }

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

    @Basic
    @Column(name = "nickname", nullable = false, length = 255)
    public String getNickname() {
        return nickname;
    }

    public void setNickname(String nickname) {
        this.nickname = nickname;
    }

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

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

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        User that = (User) o;
        return Objects.equals(id, that.id) &&
                Objects.equals(email, that.email) &&
                Objects.equals(password, that.password) &&
                Objects.equals(nickname, that.nickname);
    }

    @Override
    public int hashCode() {
        return Objects.hash(id, email, password, nickname);
    }
}

Dependencies

**   <dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jpa</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-rest</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jersey</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-security</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web-services</artifactId>
    </dependency>
    <dependency>
        <groupId>de.codecentric</groupId>
        <artifactId>spring-boot-admin-starter-server</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.security.oauth</groupId>
        <artifactId>spring-security-oauth2</artifactId>
        <version>2.3.3.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.restdocs</groupId>
        <artifactId>spring-restdocs-mockmvc</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>5.2.3.Final</version>
    </dependency>
    <dependency>
        <groupId>javax.persistence</groupId>
        <artifactId>persistence-api</artifactId>
        <version>1.0.2</version>
    </dependency>
</dependencies>**

Issue:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory; nested exception is org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: user, for columns: [org.hibernate.mapping.Column(roles)]

Answer 1

Try to add below @ElementCollection annotation.

@ElementCollection(targetClass=Role.class)
@JsonIgnore
    @ManyToMany(fetch = FetchType.EAGER)
    @JoinTable(name = "user_role",
            joinColumns = { @JoinColumn(name = "email") },
            inverseJoinColumns = { @JoinColumn(name = "role_id") })
    private Set<Role> roles = new HashSet<>();

NOTE : (targetClass=Role.class) is optional.

Answer 2

This issue relates to access strategy , in your User Class access strategy is determined by @Id annotation(which is put on getter method getId() ).

So you should put your annotations:

@JsonIgnore
@ManyToMany(fetch = FetchType.EAGER)
@JoinTable(name = "user_role",
        joinColumns = { @JoinColumn(name = "email") },
        inverseJoinColumns = { @JoinColumn(name = "role_id") })

right on getter method getRoles()