我遇到了 @ManyToMany 集合在数据加载时未填充的问题。我尝试过 FetchType.LAZY 和 FetchType.EAGER,结果没有任何变化。
当我打印用户对象时,角色集合对象为空。
用户 [userId=2、firstName=Ajay、lastName=C、电子邮件=admin.demo@gmail.com、密码=12345、角色=[]]
还尝试添加引用列。但没有成功。
请协助。
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
}
最佳答案
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;
}
这里我添加了
- cascade = CascadeType.ALL
- catalog = "\"PLATFORM_PROD_IOT\"" instead of schema = "\"PLATFORM_PROD_IOT\""
- nullable = false, updatable = false in @JoinColumn
还发现了相关的 - collection not populating in many to many relationship
关于java - spring-boot-starter-data-jpa@ManyToMany 集合未填充,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54313929/