Reputation: 1221
I have 2 tables in MySql and I have mapped them using hibernate in Spring: users and roles .
I have created one more table: user_roles but I don't know how to map it in hibernate.
You can see the table structure below:
CREATE TABLE users (
username varchar(30) NOT NULL,
email varchar(50) NOT NULL,
password varchar(255) NOT NULL,
first_name varchar(40) NOT NULL,
last_name varchar(40) NOT NULL,
date_of_birth Date,
phone_number varchar(20),
PRIMARY KEY (username)
);
CREATE TABLE roles (
role_id INTEGER NOT NULL AUTO_INCREMENT,
name VARCHAR(255),
PRIMARY KEY (role_id)
);
CREATE TABLE user_roles (
username VARCHAR(30) NOT NULL,
role_id INTEGER NOT NULL,
PRIMARY KEY (username, role_id)
);
Here is the mapping for the roles tables:
@Entity
@Table(name = "roles")
public class Role implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name="role_id")
private Integer id;
private String name;
}
Here is the mapping for the users table:
@Entity
@Table(name = "users")
@JsonInclude(JsonInclude.Include.NON_NULL)
public class User implements Serializable {
@Id
@NotEmpty
@Size(min = 5, max = 15)
@Column(name = "username")
private String username;
@Email
@NotEmpty
@Column(name = "email")
private String email;
@NotEmpty
@Size(min = 5)
@Column(name = "password")
private String password;
@NotEmpty
@Size(max = 40)
@Column(name = "first_name")
private String firstName;
@NotEmpty
@Size(max = 40)
@Column(name = "last_name")
private String lastName;
...
}
I have created the POJO for the user_role table, but I don't know how to use hibernate on it, I am using @EmbeddedId annotation but it is not working. I don't know how to show the 2 classes above that they are embeddable
@Entity
@Table(name = "user_roles")
@JsonInclude(JsonInclude.Include.NON_NULL)
public class UserRole implements Serializable {
public UserRole() { }
public UserRole(User username, Role role_id) {
this.username = username;
this.role_id = role_id;
}
private static final long serialVersionUID = -2947211066236048069L;
@EmbeddedId
private User username;
@EmbeddedId
private Role role_id;
}
How can I map the "UserRole" class to 'user_role' in hibernate? Thank you!
Upvotes: 0
Views: 223
Reputation: 211
There are two different ways which you can map user_roles table, which I suggest the first one :
1.
@Entity
@Table(name = "users")
public class User
{
@ManyToMany(targetEntity = Role.class)
@JoinTable(name = "users_roles", joinColumns = @JoinColumn(name = "user_id"), inverseJoinColumns = @JoinColumn(name = "role_id"))
@NotAudited
private Set<Role> roles = new HashSet<>();
}
2.
@Embeddable
public class UserRoleId implements java.io.Serializable
{
@Column(name = "user_id", nullable = false)
private long userId;
@Column(name = "role_id", nullable = false)
private long roleId;
public UserRoleId()
{
}
public UserRoleId(long userId, long roleId)
{
this.userId = userId;
this.roleId = roleId;
}
//hashcode equal
}
Then create the entity.
@Entity
@Table(name = "users_roles")
public class Userroles implements java.io.Serializable
{
@EmbeddedId
private UserRoleId id;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "user_id", nullable = false, insertable = false, updatable = false)
@NotNull
private Users users;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "role_id", nullable = false, insertable = false, updatable = false)
@NotNull
private Role role;
}
Upvotes: 1