Hibernate：插入多对一：错误列不能为null

Question

各位，我在将实体多对一插入时遇到了一个问题。问题：我想插入一个新记录：staffId，type，reason。但是表记录和employee有多对一的关系，所以我不知道如何在这个表中插入类为DTO is staffId或employee employee的属性，以及如何插入它。太多了！

下面的代码：

员工实体

@Entity
@Table(name = "STAFF")
public class Employee {
@Column(name = "DEPARTMENT_ID")
private Long departmentId;
@ManyToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(insertable = false, updatable = false)
private Department department;

记录实体

@Entity
@Table(name = "Records", catalog = "Assignment")
public class Records implements java.io.Serializable {

/**
 * 
 */
private static final long serialVersionUID = 1L;
private Long id;
private Employee Employee;
private boolean type;
private String reason;
private Date date;
@ManyToOne(fetch = FetchType.LAZY)
@JoinColumn(name = "StaffId", nullable = false)
public Employee getEmployee() {
    return this.Employee;

记录到\

在controller中，我不知道使用哪个类，Form或DTO公共类RecordDto{

  /*=====================================================================================================
 *===== PRIVATE PROPERTIES                                                                        =====
 *=====================================================================================================*/

/**
 * trunglq_department.ID
 */
private Long id;

/**
 * trunglq_department.Employee
 */
private Employee Employee;

/**
 * trunglq_department.type
 */
private boolean type;

/**
 * trunglq_department.reason
 */
private String reason;

/**
 * trunglq_department.date
 */
private Date date;

记录表格

public class RecordForm {

/*=====================================================================================================
 *===== PRIVATE PROPERTIES                                                                        =====
 *=====================================================================================================*/

/**
 * trunglq_department.ID
 */
private Long id;

/**
 * trunglq_department.Employee
 */
private int staffId;

/**
 * trunglq_department.type
 */
private boolean type;

/**
 * trunglq_department.reason
 */
private String reason;

/**
 * trunglq_department.date
 */
private Date date;

存储库

@Override
public Long insert(Records record) {
    record.setDate(new Date());
    return (Long)super.insert(record);
}

服务

@Override
public Long create(RecordForm recordForm) {
    recordForm.setStaffId(9);
    Records record = (Records) DataTransformUtil.transform(recordForm, Records.class);
    return (Long)recordRepository.insert(record);
}

控制器

在控制器中，我不知道使用哪个类，Form还是DTO

 @PostMapping("/create")
public String index(Model model, @ModelAttribute("formRecord") RecordForm recordForm,HttpServletRequest request) {
    recordService.create(recordForm);
    return "/employee/index";
}

JSP

jsp是模态的，当单击一行时，我在表中获取数据。其中，数据包括：员工ID、类型、原因。错误代码为空StaffId。

form:form modelAttribute="formRecord" action="record/create"
                method="POST">
                <!-- Modal Header -->
                <div class="modal-header">
                    <h4 class="modal-title">
                        Ghi nhận nhân viên có ID:
                            <label class="idStaff"
                            style="font-size: 20px"></label>
                    </h4>
                    <button type="button" class="close" data-dismiss="modal">&times;</button>
                </div>

                <!-- Modal body -->

                <div class="modal-body">
                        <form:hidden path="staffId" class="idStaff"/>
                    <div class="custom-control custom-radio custom-control-inline">
                        <form:radiobutton path="type" class="custom-control-input"
                            id="customRadio" name="radioRecord" value="0" />
                        <label class="custom-control-label" for="customRadio">Achievement</label>
                    </div>
                    <div class="custom-control custom-radio custom-control-inline">
                        <form:radiobutton path="type" class="custom-control-input"
                            id="customRadio2" name="radioRecord" value="1" />
                        <label class="custom-control-label" for="customRadio2">Mistake</label>
                    </div>
                    <div class="form-group">
                        <label for="reason">Reason:</label>
                        <form:textarea class="form-control" rows="5" id="comment"
                            path="reason" />
                    </div>

                </div>

                <!-- Modal footer -->
                <div class="modal-footer">
                    <button type="submit" class="btn btn-success">Save</button>
                    <button type="button" class="btn btn-danger" data-dismiss="modal">Close</button>
                </div>
            </form:form>

错误代码

java.sql.SQLIntegrityConstraintViolationException: Column 'StaffId' cannot be null

Answer 1

您的员工pojo缺少staffId（PK）。还有，如果已经有了部门变量，为什么还要有部门id？

您的表可能有staff\u id、department\u id、staff\u name等，因此对于多对一，您只需添加外键引用，在pojos中，您必须将joincolumn指定为department\u id。类似于您的记录实体。