java - org.hibernate.PropertyAccessException:无法通过反射 getter 获取字段值

我到处寻找答案，这似乎与思考有关，但是由于我没有处理这些思考，因此不确定如何进行。我正在尝试构建一个HQL查询，该查询仅从表中返回与FK列匹配另一个表中PK的表中的行。

这是我的代码:

实体书:

@Entity
@Table(name="book")
public class Book {

@Id
private String bookNumber;
private String bookName;
private String bookDescription;
private double bookPrice;

@ManyToOne(cascade=CascadeType.ALL)
@JoinColumn(name="shelfnumber")
Shelf shelf;

实体架:

@Entity
@Table(name="shelf")
public class Shelf {

@Id
private String shelfNumber;

@OneToMany(mappedBy="shelf",cascade=CascadeType.ALL)
Set<Book> shelfBooks;

注意:两个实体类都有getter / setter

动作类:

    DynaActionForm searchForm =((DynaActionForm)form);
    String shelfNum = searchForm.getString("shelfNum");

    SessionFactory sessionFactory = new   Configuration().configure().buildSessionFactory();
    Session session = sessionFactory.openSession();
    session.beginTransaction();

    try{
        session.getEntityMode();
        Query query = session.createQuery("FROM Book B WHERE B.shelf = :shelfNum"); //here is where the error happens: B.shelf is the problem but don't know why
        query.setParameter("shelfNum", shelfNum);
        List books = query.list();
        request.setAttribute("books", books);

    } finally{
        session.close();
    }

我收到错误消息:

org.hibernate.PropertyAccessException: could not get a field value by reflection getter of com.library.entity.Shelf.shelfNumber

再往下看，我看到:

Caused by: java.lang.IllegalArgumentException: Can not set java.lang.String field com.library.entity.Shelf.shelfNumber to java.lang.String

感谢您的任何帮助!

最佳答案

您的查询将Shelf实例与String实例进行比较。那行不通。 Shelf是Shelf。这不是String。

查询应该是

select b from Book b where b.shelf.shelfNumber = :shelfNum

另外，请告诉我您实际上并没有在每个请求中都重新创建SessionFactory!

并请stop using raw types。我们现在不在2003年。