Java jComboBox给出org.hibernate.PropertyAccessException错误

有两个jComboBox。。和2班。当窗体加载事件时，它将填充JCombox1，当ActionEvent触发时，它将加载另一个类，并选择JCombox1

我想从jComboBox.GetSelectItem方法中获取PersonelID，然后用这个id调用另一个类

    Exception in thread "AWT-EventQueue-0" 
javax.persistence.PersistenceException: org.hibernate.PropertyAccessException: 
could not get a field value by reflection getter of DBClasses.Unvan.unvanID

这是我的密码

 private void UnvanAl()
{
if (jComboBox1.getSelectedItem() != null) {
         EntityManagerFactory emf = Persistence.createEntityManagerFactory("SwingDenemePU");
    EntityManager em = emf.createEntityManager();
    Query sorgu = em.createQuery("select p from Personel p where p.unvanID = :id");
    int id = ((Unvan)jComboBox1.getSelectedItem()).getUnvanID();

    sorgu.setParameter("id", id);
    personelList = sorgu.getResultList();
    Object[] items = new Object[personelList.size()];
    for (int i = 0; i < personelList.size(); i++) {
        Personel personel = personelList.get(i);
        items[i]=personel.getPersonelAdSoyad();

    }

    DefaultComboBoxModel def = new DefaultComboBoxModel(items);
    jComboBox2.setModel(def);
    }

}


private void jComboBox1ActionPerformed(java.awt.event.ActionEvent evt) {
   UnvanAl();

}

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是否有unvanID属性的getter/setter？

作为注释而不是答案发布