EntityManager remove throws Object：null不是一个已知的实体类型 [英] EntityManager remove throws Object: null is not a known entity type

问题描述

我试图使用EntityManager删除数据库中的记录。我正在使用EJB JPA。

它产生错误： Object：null不是一个已知的实体类型。 / p>

这是我的代码：

  public void deleteAppointment（int staffID， int appointmentID）{
 try {
 
 StaffApointmentsPK staffApointmentsPK = new StaffApointmentsPK（）; 
 staffApointmentsPK.setAppointmentId（约会ID）; 
 staffApointmentsPK.setStaffId（staffID）; 
 
 StaffApointments staffApointments = staffApointmentsFacade.find（staffApointmentsPK）; 
 
 System.out.println（staff app type+ staffApointments）; 
 
 em.remove（staffApointments）; 
 em.flush（）; 
  

但是在我早期的调用下面的函数中，它是非常相似的，但它正在工作。我不明白是什么问题，因为我正在使用 staffApointmentsFacade 搜索该实体。

这是我的其他功能有效：

  public StaffApointments getPatientAppointmentDetails（int appointmentID，int staffID）{
 
 StaffApointmentsPK staffApointmentsPK = new StaffApointmentsPK（）; 
 staffApointmentsPK.setAppointmentId（约会ID）; 
 staffApointmentsPK.setStaffId（staffID）;工作人员
 
 return staffApointments; 
} 
  

任何帮助将不胜感激。谢谢

编辑

我通过切换 int staffID，int appointmentID 感谢您的帮助！

解决方案

我通过分别切换int staffID，int appointmentID来解决它。感谢您的帮助@Donovan和@ ma-ve-rick

I am trying to delete a record in the database using EntityManager. I am using EJB JPA.

It produces the error : Object: null is not a known entity type.

Here is my code:

public void deleteAppointment(int staffID, int appointmentID) {
    try {

        StaffApointmentsPK staffApointmentsPK = new StaffApointmentsPK();
        staffApointmentsPK.setAppointmentId(appointmentID);
        staffApointmentsPK.setStaffId(staffID);

        StaffApointments staffApointments = staffApointmentsFacade.find(staffApointmentsPK);

        System.out.println("staff app type " + staffApointments);

        em.remove(staffApointments);
        em.flush();

But in my early call to the function below, it is very similar but it is working. I do not understand what is the problem because I am searching for the entity first using staffApointmentsFacade.

Here is my other function which works:

public StaffApointments getPatientAppointmentDetails(int appointmentID, int staffID) {

        StaffApointmentsPK staffApointmentsPK = new StaffApointmentsPK();
        staffApointmentsPK.setAppointmentId(appointmentID);
        staffApointmentsPK.setStaffId(staffID);
        StaffApointments staffApointments = staffApointmentsFacade.find(staffApointmentsPK);

return staffApointments;
}

Any help would be appreciated. Thanks

EDIT

I solved it by switching the int staffID, int appointmentID respectively. Thanks for all your help!

解决方案

I solved it by switching the int staffID, int appointmentID respectively. Thanks for all your help @Donovan and @ma-ve-rick

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