Question

我正在尝试使用EntityManager删除数据库中的记录。我正在使用EJB JPA。

它产生错误：Object: null is not a known entity type。

这是我的代码：

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();

但是在我之前对下面这个函数的调用中，它非常相似，但它正在工作。我不明白是什么问题，因为我首先使用staffApointmentsFacade搜索实体。

这是我的另一个功能：

public StaffApointments getPatientAppointmentDetails(int appointmentID, int staffID) {

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

return staffApointments;
}

任何帮助将不胜感激。感谢

修改

我分别通过切换int staffID, int appointmentID解决了这个问题。谢谢你的帮助！

Answer 1

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

EntityManager remove throws对象：null不是已知的实体类型

1 个答案: