Full error message:
Exception occurred during event dispatching: org.hibernate.HibernateException: identifier of an instance of members.Appointment was altered from 8 to 8 at org.hibernate.event.def.DefaultFlushEntityEventListener.checkId(DefaultFlushEntityEventListener.java:58) at org.hibernate.event.def.DefaultFlushEntityEventListener.getValues(DefaultFlushEntityEventListener.java:157) at org.hibernate.event.def.DefaultFlushEntityEventListener.onFlushEntity(DefaultFlushEntityEventListener.java:113) at org.hibernate.event.def.AbstractFlushingEventListener.flushEntities(AbstractFlushingEventListener.java:196) at org.hibernate.event.def.AbstractFlushingEventListener.flushEverythingToExecutions(AbstractFlushingEventListener.java:76) at org.hibernate.event.def.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:26) at org.hibernate.impl.SessionImpl.flush(SessionImpl.java:1000) at org.hibernate.impl.SessionImpl.managedFlush(SessionImpl.java:338) at org.hibernate.transaction.JDBCTransaction.commit(JDBCTransaction.java:106) at members.AppointmentDialog.jButtonSaveActionPerformed(AppointmentDialog.java:279) at members.AppointmentDialog.access$000(AppointmentDialog.java:21) at members.AppointmentDialog$1.actionPerformed(AppointmentDialog.java:101) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1849) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2169) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258) at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236) at java.awt.Component.processMouseEvent(Component.java:5517) at javax.swing.JComponent.processMouseEvent(JComponent.java:3135) at java.awt.Component.processEvent(Component.java:5282) at java.awt.Container.processEvent(Container.java:1966) at java.awt.Component.dispatchEventImpl(Component.java:3984) at java.awt.Container.dispatchEventImpl(Container.java:2024) at java.awt.Component.dispatchEvent(Component.java:3819) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3892) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822) at java.awt.Container.dispatchEventImpl(Container.java:2010) at java.awt.Window.dispatchEventImpl(Window.java:1791) at java.awt.Component.dispatchEvent(Component.java:3819) at java.awt.EventQueue.dispatchEvent(EventQueue.java:463) at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:153) at java.awt.Dialog$1.run(Dialog.java:535) at java.awt.Dialog$2.run(Dialog.java:563) at java.security.AccessController.doPrivileged(Native Method) at java.awt.Dialog.show(Dialog.java:561) at java.awt.Component.show(Component.java:1302) at java.awt.Component.setVisible(Component.java:1255) at admin.AdminOptionsForm.jButtonSetAppointmentActionPerformed(AdminOptionsForm.java:238) at admin.AdminOptionsForm.access$800(AdminOptionsForm.java:24) at admin.AdminOptionsForm$9.actionPerformed(AdminOptionsForm.java:145) at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1849) at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2169) at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420) at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258) at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236) at java.awt.Component.processMouseEvent(Component.java:5517) at javax.swing.JComponent.processMouseEvent(JComponent.java:3135) at java.awt.Component.processEvent(Component.java:5282) at java.awt.Container.processEvent(Container.java:1966) at java.awt.Component.dispatchEventImpl(Component.java:3984) at java.awt.Container.dispatchEventImpl(Container.java:2024) at java.awt.Component.dispatchEvent(Component.java:3819) at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4212) at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3892) at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3822) at java.awt.Container.dispatchEventImpl(Container.java:2010) at java.awt.Window.dispatchEventImpl(Window.java:1791) at java.awt.Component.dispatchEvent(Component.java:3819) at java.awt.EventQueue.dispatchEvent(EventQueue.java:463) at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:163) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:157) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:149) at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)
In Java, I had a class Appointment mapped to a MySQL table `appointment` using Hibernate as follows:
<hibernate-mapping> <class name="members.Appointment" table="appointment"> <id name="idAppointment" column="idappointment" type="short"> <generator class="native"/> </id> <many-to-one name="member" column="idmember" not-null="true" foreign-key="fk_idmember"/> <property name="startDate" type="timestamp" column="start_date"/> <property name="duration" type="short" column="duration" length="3"/> <property name="cancelled" type="boolean"/> </class> </hibernate-mapping>
I was getting the error when inserting a new appointment into the database.
The problem was that the idAppointment member variable in the Java class and the idappointment field in the MySQL database table were of the type int. So why the hell did I have the type short in the mapping? The answer is simple: because of the copy paste. So the correct code is:
<id name="idAppointment" column="idappointment"> <generator class="native"/> </id>
Conclusion: copy paste is sometimes evil.