spring-boot-starter-data-JPA @ ManyToMany集合未填充

Question

我遇到了一个问题，@ManyToMore集合没有在数据加载时填充。我尝试了FetchType.LAZY和FetchType.EAGER，结果没有变化。

打印用户对象时，角色集合对象为空。

用户 [userId=2，名字=阿贾伊，姓氏=C，email=[e-mail]，密码=12345，角色=[]]

也尝试通过添加引用的列。但不起作用。

请在这方面协助。

用户和角色实体如下。

@Entity
@Table(name = "\"USER\"", schema = "\"PLATFORM_PROD_IOT\"", uniqueConstraints = {
     @UniqueConstraint(columnNames = { "\"EMAIL_ID\"" }) })
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Size(min = 1, max = 50)
    @Column(name = "\"USER_ID\"")
    private Long userId;

    @NotBlank
    @Size(min = 3, max = 50)
    @Column(name = "\"FIRST_NAME\"")
    private String firstName;

    @NotBlank
    @Size(min = 3, max = 50)
    @Column(name = "\"LAST_NAME\"")
    private String lastName;

    @NaturalId
    @NotBlank
    @Size(max = 50)
    @Email
    @Column(name = "\"EMAIL_ID\"")
    private String email;

    @NotBlank
    @Size(min = 3, max = 100)
    @Column(name = "\"PASSWORD\"")
    private String password;


    @ManyToMany(fetch = FetchType.LAZY)
    @JoinTable(name = "\"USER_ROLE_MAPPING\"", schema = "\"\PLATFORM_PROD_IOT\"", joinColumns = @JoinColumn(name = "\"USER_ID\""), inverseJoinColumns = @JoinColumn(name = "\"ROLE_ID\""))
    private Set<Role> roles = new HashSet<>();

//Getters and Setters

}

@Entity
@Table(name = "\"ROLE\"",schema="\"PLATFORM_PROD_IOT\"")
public class Role {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="\"ROLE_ID\"")
    private Long roleId;

    @Column(name="\"ROLE_NAME\"")
    private RoleName name;
//Getters and Setters
}

Answer 1

你可以试试这个 -

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinTable(name = "\"USER_ROLE_MAPPING\"", catalog = "\"PLATFORM_PROD_IOT\"", joinColumns = { 
            @JoinColumn(name = "\"USER_ID\"", nullable = false, updatable = false) }, 
            inverseJoinColumns = { @JoinColumn(name = "\"ROLE_ID\"", 
                    nullable = false, updatable = false) })
    private Set<Role> roles = new HashSet<>();


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

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

在这里我添加了

< li>cascade = CascadeType。所有 < Li > catalog = " " PLATFORM _ PROD _ IOT \ " "而不是schema = " \ " PLATFORM _ PROD _ IOT \ " " < li >在@JoinColumn中，nullable = false，updatable = false

还发现了一个相关的集合，没有在多对多关系中填充。