Question

我有课程：

@Entity
@Table(schema = "master", name = "master_mapping")
public class MasterMapping extends AuditedEntity {

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "master_field_id")
    private MasterFields masterField;

    @JsonIgnore
    public MasterFields getMasterField() {
        return masterField;
    }

    public void setMasterField(MasterFields masterField) {
        this.masterField = masterField;
    }

}

和

@Entity
@Table(schema = "master", name = "master_fields")
public class MasterFields extends AuditedEntity {

    private String label;

    @OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, mappedBy = "masterField")
    private List<MasterMapping> mappedFields;

    public String getLabel() {
        return label;
    }

    public void setLabel(String label) {
        this.label = label;
    }

    public List<MasterMapping> getMappedFields() {
        return mappedFields;
    }

    public void setMappedFields(List<MasterMapping> mappedFields) {
        this.mappedFields = mappedFields;
    }
}

和id

的公共类

@MappedSuperclass
public class AuditedEntity {

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

   public int getId() {
       return id;
   }

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

}

我正在尝试使用MasterMapping保存MasterFields对象，但我收到错误：

Hibernate：插入master.master_fields（标签）值（？）

休眠：选择currval（'master.master_fields_id_seq'）

Hibernate：插入master.master_mapping（master_field_id）值（？）

SQL错误：0，SQLState：23502

错误：“master_field_id”列中的空值违反了非空约束详细信息：失败的行包含（null）。

javax.persistence.PersistenceException：org.hibernate.exception.ConstraintViolationException：无法执行语句

我正在尝试使用EntityManager.merge（）将其保存到db。我看到hibernate无法从MasterFields对象获取生成的id。怎么解决它？

错误：“master_field_id”列中的空值违反非空约束

0 个答案: