Mysql自动生成PK用于另一个表和JPA的问题

我的用例如下：我使用MySQL和jpa2，我有两个实体：Order和LineItem，它们通过一个OneToMany关系关联

我希望GUI层能够同时将订单和行项目保存在一起

请记住，订单主键是MySQL自动生成的，是LineItem主键的一部分，我不知道如何检索生成的订单主键，以便将其用于同一事务中的LineItem主键

有人能帮忙吗

根据您的反馈，这里是一些来自实体的示例代码（我实际上编写了上面的用例/域。我的更复杂，所以您不会看到任何订单或行项目）

@实体
@表（name=“广告”）
@继承（策略=InheritanceType.JOINED）
@鉴别器列（name=“status\u need\u ID”，鉴别器类型=鉴别器类型.INTEGER）
@命名查询({
@NamedQuery（name=“advision.findAll”，query=“从广告a中选择a”），
@NamedQuery（name=“advision.findbyadvertisementtid”，query=“从广告a中选择一个，其中a.advisementId=：advisementId”），
@NamedQuery（name=“advision.findbyadvertisementttitle”，query=“从广告a中选择一个，其中a.advisementTitle=：advisementTitle”），
@NamedQuery（name=“advision.findByAdvertisementCreationDate”，query=“从广告a中选择a，其中a.advisioncreationdate=：advisioncreationdate”），
@NamedQuery（name=“advision.findByStatusneedID”，query=“从广告a中选择a，其中a.statusneedID=：statusneedID”）}
公共类广告实现了可序列化{
私有静态最终长serialVersionUID=1L；
@身份证
@GeneratedValue（策略=GenerationType.IDENTITY）
@基本（可选=假）
@列（name=“advision\u ID”，nullable=false）
私有整数广告ID；
@基本（可选=假）
@列（name=“advision\u title”，null=false，长度=200）
私有字符串广告标题；
@列（name=“广告\创建\日期”）
@时态（TemporalType.TIMESTAMP）
私人日期广告创意日期；
@基本（可选=假）
@高球
@列（name=“advertization\u body”，nullable=false，length=2147483647）
私有字符串广告主体；
@列（name=“status\u need\u ID”）
私有整数statusneedID；
@JoinTable（name=“postcode\u to\u advision\u join”，JointColumns={
@JoinColumn（name=“advision\u ID”，referencedColumnName=“advision\u ID”，nullable=false）}，inverseJoinColumns={
@JoinColumn（name=“postcode\u ID”，referencedColumnName=“postcode\u ID”，nullable=false）}）
@许多
私人收藏邮政编码收藏；
@JoinTable（name=“广告时间到join”，joinColumns={
@JoinColumn（name=“advision\u ID”，referencedColumnName=“advision\u ID”，nullable=false）}，inverseJoinColumns={
@JoinColumn（name=“duration\u ID”，referencedColumnName=“duration\u ID”，nullable=false）}）
@许多
私人收藏期限收藏；
@JoinTable（name=“完整或部分时间基础”到“广告”，joinColumns={
@JoinColumn（name=“advision\u ID”，referencedColumnName=“advision\u ID”，nullable=false）}，inverseJoinColumns={
@JoinColumn（name=“完整”或“部分”时间基础\u ID”，referencedColumnName=“完整”或“部分”时间基础\u ID”，nullable=false）}）
@许多
私人收集全部或部分时间基本收集；
@JoinTable（name=“广告”到“儿童护理”类型，JointColumns={
@JoinColumn（name=“advision\u ID”，referencedColumnName=“advision\u ID”，nullable=false）}，inverseJoinColumns={
@JoinColumn（name=“child\u care\u type\u ID”，referencedColumnName=“child\u care\u type\u ID”，nullable=false）}）
@许多
私人收藏childCareTypeCollection；
@JoinTable（name=“广告\学校\假日\加入”，JointColumns={
@JoinColumn（name=“advision\u ID”，referencedColumnName=“advision\u ID”，nullable=false）}，inverseJoinColumns={
@JoinColumn（name=“school\u holiday\u ID”，referencedColumnName=“school\u holiday\u ID”，nullable=false）}）
@许多
私人收藏学校假期收藏；
@JoinTable（name=“就业合同”到“广告”，JointColumns={
@JoinColumn（name=“advision\u ID”，referencedColumnName=“advision\u ID”，nullable=false）}，inverseJoinColumns={
@JoinColumn（name=“employment\u contract\u ID”，referencedColumnName=“employment\u contract\u ID”，nullable=false）}）
@许多
私人收藏雇佣合同收藏；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“广告”）
私人收藏广告到TimeSlottoDayJoinCollection；
@OneToMany（cascade=CascadeType.ALL，mappedBy=“advertisementID”）
私人募捐；
@OneTONE（cascade=CascadeType.ALL，mappedBy=“广告”）
私人的父母父母的父母；
@OneTONE（cascade=CascadeType.ALL，mappedBy=“广告”）
私人父母子女广告；
@JoinColumn（name=“child\u care\u location\u ID”，referencedColumnName=“child\u care\u location\u ID”，nullable=false）
@多通（可选=假）
私有ChildCareLocation childcarelocationID；
@JoinColumn（name=“account\u ID”，referencedColumnName=“account\u ID”，nullable=false）
@多通（可选=假）
私人帐户账号；
@实体
@表（name=“广告”到“时间”到“时段”到“日期”加入”，schema=“bignibou”）
@命名查询({
@NamedQuery（name=“AdvertisementToTimeSlotToDayJoin.findAll”，query=“从AdvertisementToTimeSlotToDayJoin a中选择a”），
@命名
@Entity
@Table(name = "advertisement")
@Inheritance(strategy = InheritanceType.JOINED)
@DiscriminatorColumn(name = "status_need_ID", discriminatorType = DiscriminatorType.INTEGER)
@NamedQueries({
    @NamedQuery(name = "Advertisement.findAll", query = "SELECT a FROM Advertisement a"),
    @NamedQuery(name = "Advertisement.findByAdvertisementID", query = "SELECT a FROM Advertisement a WHERE a.advertisementID = :advertisementID"),
    @NamedQuery(name = "Advertisement.findByAdvertisementTitle", query = "SELECT a FROM Advertisement a WHERE a.advertisementTitle = :advertisementTitle"),
    @NamedQuery(name = "Advertisement.findByAdvertisementCreationDate", query = "SELECT a FROM Advertisement a WHERE a.advertisementCreationDate = :advertisementCreationDate"),
    @NamedQuery(name = "Advertisement.findByStatusneedID", query = "SELECT a FROM Advertisement a WHERE a.statusneedID = :statusneedID")})
public class Advertisement implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "advertisement_ID", nullable = false)
    private Integer advertisementID;
    @Basic(optional = false)
    @Column(name = "advertisement_title", nullable = false, length = 200)
    private String advertisementTitle;
    @Column(name = "advertisement_creation_date")
    @Temporal(TemporalType.TIMESTAMP)
    private Date advertisementCreationDate;
    @Basic(optional = false)
    @Lob
    @Column(name = "advertisement_body", nullable = false, length = 2147483647)
    private String advertisementBody;
    @Column(name = "status_need_ID")
    private Integer statusneedID;
    @JoinTable(name = "postcode_to_advertisement_join", joinColumns = {
        @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false)}, inverseJoinColumns = {
        @JoinColumn(name = "postcode_ID", referencedColumnName = "postcode_ID", nullable = false)})
    @ManyToMany
    private Collection<Postcode> postcodeCollection;
    @JoinTable(name = "advertisement_to_duration_join", joinColumns = {
        @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false)}, inverseJoinColumns = {
        @JoinColumn(name = "duration_ID", referencedColumnName = "duration_ID", nullable = false)})
    @ManyToMany
    private Collection<Duration> durationCollection;
    @JoinTable(name = "full_or_part_time_basis_to_advertisement_join", joinColumns = {
        @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false)}, inverseJoinColumns = {
        @JoinColumn(name = "full_or_part_time_basis_ID", referencedColumnName = "full_or_part_time_basis_ID", nullable = false)})
    @ManyToMany
    private Collection<FullOrPartTimeBasis> fullOrPartTimeBasisCollection;
    @JoinTable(name = "advertisement_to_child_care_type_join", joinColumns = {
        @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false)}, inverseJoinColumns = {
        @JoinColumn(name = "child_care_type_ID", referencedColumnName = "child_care_type_ID", nullable = false)})
    @ManyToMany
    private Collection<ChildCareType> childCareTypeCollection;
    @JoinTable(name = "advertisement_to_school_holiday_join", joinColumns = {
        @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false)}, inverseJoinColumns = {
        @JoinColumn(name = "school_holiday_ID", referencedColumnName = "school_holiday_ID", nullable = false)})
    @ManyToMany
    private Collection<SchoolHoliday> schoolHolidayCollection;
    @JoinTable(name = "employment_contract_to_advertisement_join", joinColumns = {
        @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false)}, inverseJoinColumns = {
        @JoinColumn(name = "employment_contract_ID", referencedColumnName = "employment_contract_ID", nullable = false)})
    @ManyToMany
    private Collection<EmploymentContract> employmentContractCollection;
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "advertisement")
    private Collection<AdvertisementToTimeSlotToDayJoin> advertisementToTimeSlotToDayJoinCollection;
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "advertisementID")
    private Collection<Salary> salaryCollection;
    @OneToOne(cascade = CascadeType.ALL, mappedBy = "advertisement")
    private ParentToParentAdvertisement parentToParentAdvertisement;
    @OneToOne(cascade = CascadeType.ALL, mappedBy = "advertisement")
    private ParentToChildMinderAdvertisement parentToChildMinderAdvertisement;
    @JoinColumn(name = "child_care_location_ID", referencedColumnName = "child_care_location_ID", nullable = false)
    @ManyToOne(optional = false)
    private ChildCareLocation childcarelocationID;
    @JoinColumn(name = "account_ID", referencedColumnName = "account_ID", nullable = false)
    @ManyToOne(optional = false)
    private Account accountID;



@Entity
@Table(name = "advertisement_to_time_slot_to_day_join",schema="bignibou")
@NamedQueries({
    @NamedQuery(name = "AdvertisementToTimeSlotToDayJoin.findAll", query = "SELECT a FROM AdvertisementToTimeSlotToDayJoin a"),
    @NamedQuery(name = "AdvertisementToTimeSlotToDayJoin.findByDayID", query = "SELECT a FROM AdvertisementToTimeSlotToDayJoin a WHERE a.advertisementToTimeSlotToDayJoinPK.dayID = :dayID"),
    @NamedQuery(name = "AdvertisementToTimeSlotToDayJoin.findByTimeslotID", query = "SELECT a FROM AdvertisementToTimeSlotToDayJoin a WHERE a.advertisementToTimeSlotToDayJoinPK.timeslotID = :timeslotID"),
    @NamedQuery(name = "AdvertisementToTimeSlotToDayJoin.findByAdvertisementID", query = "SELECT a FROM AdvertisementToTimeSlotToDayJoin a WHERE a.advertisementToTimeSlotToDayJoinPK.advertisementID = :advertisementID")})
public class AdvertisementToTimeSlotToDayJoin implements Serializable {
    private static final long serialVersionUID = 1L;
    @EmbeddedId
    protected AdvertisementToTimeSlotToDayJoinPK advertisementToTimeSlotToDayJoinPK;
    @JoinColumn(name = "time_slot_ID", referencedColumnName = "time_slot_ID", nullable = false, insertable = false, updatable = false)
    @ManyToOne(optional = false)
    private TimeSlot timeSlot;
    @JoinColumn(name = "day_ID", referencedColumnName = "day_ID", nullable = false, insertable = false, updatable = false)
    @ManyToOne(optional = false)
    private Day day;
    @JoinColumn(name = "advertisement_ID", referencedColumnName = "advertisement_ID", nullable = false, insertable = false, updatable = false)
    @ManyToOne(optional = false)
    private Advertisement advertisement;

@Entity
public class Order {
    @Id 
    @GeneratedValue(strategy=GenerationType.AUTO) 
    long id;

    @OneToMany(cascade={})
    Set<LineItem> lineItems;
}