我有一个问题，就是Hibernate无法在表USERS上确定Set的类型。我试图通过一对多关系创建表INVOICES的外键。一位用户可以生成许多发票。我的User.java如下。

@Entity
@Table(name="USERS")
public class User {

    @Id
    @Column(name="User_Id",nullable=false)
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Integer user_id;


    @Column(name="NAME")
    private String name;

    @Column(name="Address")
    private String address;

    @Column(name="Designation")
    private String designation;


    private Set<Invoice> invoices;

    /*@OneToMany
    @JoinColumn(name="Rec_Invoice_ID", nullable=false)
    private Set<RecurringInvoice> recurring_invoices;*/

我正在尝试使用INVOICE-ID作为USERS表中的外键。我正在按照此处给出的说明进行
hibernate：一对多注释（外键）

    @OneToMany
    @JoinColumn(name="INVOICE_ID", nullable=false)
    public Set<Invoice> getInvoices() {
        return invoices;
    }

    public void setInvoices(Set<Invoice> invoices) {
        this.invoices = invoices;
    }

/*   public Set<RecurringInvoice> getRecurring_invoices() {
        return recurring_invoices;
    }

    public void setRecurring_invoices(Set<RecurringInvoice> recurring_invoices) {
        this.recurring_invoices = recurring_invoices;
    }
*/
    // Getters and Setters
    public Integer getUser_id() {
        return user_id;
    }

    public void setUser_id(Integer user_id) {
        this.user_id = user_id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public String getDesignation() {
        return designation;
    }

    public void setDesignation(String designation) {
        this.designation = designation;
    }

}

我的Invoice.java如下。

@Entity
@Table(name="INVOICES")
public class Invoice {


    private Integer invoice_id;

    @Column(name="Date_Created", nullable=false)
    private Timestamp dateCreated;

    @Column(name="DESCRIPTION")
    private String description;

    @Column(name="Total_Amount")
    private Double totalAmount;

    @Column(name="Tax_Amount")
    private Double taxAmount;

    @Column(name="Due_Date")
    private Timestamp dueDate;

    @Column(name="deleted")
    private boolean deleted;


    private InvoiceItemsDetails invoiceItemsDetails;


    private Client client;

    @OneToOne
    @JoinColumn(name="ID", nullable=false)
    public Client getClient() {
        return client;
    }

    public void setClient(Client client) {
        this.client = client;
    }

    public Date getDueDate() {
        return dueDate;
    }

    public void setDueDate(Timestamp dueDate) {
        this.dueDate = dueDate;
    }

    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    @Column(name="INVOICE_ID", nullable=false, insertable=false,updatable=false)
    public Integer getInvoice_id() {
        return invoice_id;
    }

    public void setInvoice_id(Integer invoice_id) {
        this.invoice_id = invoice_id;
    }

    public Date getDateCreated() {
        return dateCreated;
    }

    public void setDateCreated(Timestamp dateCreated) {
        this.dateCreated = dateCreated;
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public Double getTotalAmount() {
        return totalAmount;
    }

    public void setTotalAmount(Double totalAmount) {
        this.totalAmount = totalAmount;
    }

    public Double getTaxAmount() {
        return taxAmount;
    }

    public void setTaxAmount(Double taxAmount) {
        this.taxAmount = taxAmount;
    }

    public boolean isDeleted() {
        return deleted;
    }

    public void setDeleted(boolean deleted) {
        this.deleted = deleted;
    }

    @OneToOne
    @JoinColumn(name="Invoice_Item_Detail_id", nullable=false)
    public InvoiceItemsDetails getInvoiceItemsDetails() {
        return invoiceItemsDetails;
    }

    public void setInvoiceItemsDetails(InvoiceItemsDetails invoiceItemsDetails) {
        this.invoiceItemsDetails = invoiceItemsDetails;
    }


}