JPA/Hibernate试图在具有复合Id(和加倍属性)的实体中存储太多参数

Question

我有一个具有复合Id 的实体

@Entity
@IdClass(value = BorrowId.class)
@Table(name = "BORROW")
public class Borrow {
    @Id
    @Column(name = "BOOK_ID", insertable = false, updatable = false)
    private long bookId;
    @Id
    @Column(name = "BORROWER_ID", insertable = false, updatable = false)
    private long borrowerId;
    @Id
    @ManyToOne(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REFRESH})
    @JoinColumn(name = "BOOK_ID")
    private Book book;
    @Id
    @ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REFRESH})
    @JoinColumn(name = "BORROWER_ID")
    private Borrower borrower;
    @Id
    @Column(name = "BORROW_DATE")
    private Date borrowDate;
    @Column(name = "RETURN_DATE")
    private Date returnDate;

BorrowId具有属性（所有具有getter/setter的属性）

    private long bookId;
    private long borrowerId;
    private Date borrowDate;

和equals，hashCode方法

当我尝试持久化Borrow实体时（图书和借款人属性设置为相应的实体，然后调用entityManager.sistent（Borrow）；）我的日志中有：

休眠：插入BORROW（BORROWER_ID，BOOK_ID，RETURN_DATE，BORROW_DATE）值（？，？，？）//此插入语句正确（这是我的表）参数的值"5"无效"parameterIndex"[90008-174]

所以看起来好像有人做错了什么：）如何解决这个问题？我的实体声明有错吗？（我想使用CompositeId来学习使用它的一些知识）

Answer 1

感谢@JB nizet

@Id
@Column(name = "BOOK_ID", insertable = false, updatable = false)
private long bookId;
@Id
@Column(name = "BORROWER_ID", insertable = false, updatable = false)
private long borrowerId;
@MapsId("bookId")
@ManyToOne(fetch = FetchType.LAZY, cascade = {CascadeType.PERSIST,
                                              CascadeType.MERGE,
                                              CascadeType.REFRESH})
@JoinColumn(name = "BOOK_ID")
private Book book;
@MapsId("borrowerId")
@ManyToOne(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, 
                                               CascadeType.MERGE,
                                               CascadeType.REFRESH})
@JoinColumn(name = "BORROWER_ID")
private Borrower borrower;
@Id
@Column(name = "BORROW_DATE")
private Date borrowDate;

解决了这个问题，这很奇怪，因为在任何示例/教程中，都没有@MapsId与@IdClass一起使用。我不确定现在是否需要@JoinColumn