[appengine-java] Re: Not able to save child object in one-to-many relationship
Thanks for the info. I looked at the issue and many other people
having problem of saving child object in a one-to-many relation. I am
new to this and I don't understand completely. Is there any work-
around to save a child object. If anyone can show me an example, I
appreciate. This is really frustrating as this is basic functionality
in any relational data. In my case, Employee object already exists and
I want to create a new appointment and associate with the employee
object. If there is a different way of doing this, please help. This
has taken quite a lot of time and if this is not available in GWT, I
don't think I can use Google apps for the development of our
application. I appreciate any help.
Thanks,
Ravi
On Aug 27, 1:51 am, Frederik Pfisterer pfiste...@gmail.com wrote:
Your problem seems to be related to this open gwt
issue:http://code.google.com/p/google-web-toolkit/issues/detail?id=4976
Please star the issue to raise its attention. The workaround is not
using 1:n relationships with GWT + GAE + JDO.
Cheers,
Fred
On 26 Aug., 23:12, hampole rhamp...@gmail.com wrote:
I am trying to develop GAE application. I am using the latest GWT
SDK(2.0.4) AND App Engine SDK(1.3.6) on Eclipse3.4. I am having
problem insavinga childobjectAppointment and the parentobject
is Employee. Each Employee has many appointments and and each
appointment has one employee associated with. I have pasted the Client
code and the server code here. Please help and see what I am missing
here. I tried many different ways without success. When I retrieve the
appointments, the employee is always null. I appreciate any help or
some example that I can try. Thanks.
//Client code
public class AppointmentCreateWidget extends Composite {
private static AppointmentCreateWidgetUiBinder uiBinder = GWT
.create(AppointmentCreateWidgetUiBinder.class);
interface AppointmentCreateWidgetUiBinder extends
UiBinderWidget, AppointmentCreateWidget {
}
@UiField Button btnSaveAppointment;
@UiField TextBox tbxSubject;
@UiField ListBox lbxRoom;
@UiField ListBox lbxHost;
@UiField DateBox dbAppointStartDate;
@UiField DateBox dbAppointEndDate;
@UiField ListBox lbxStartTimeHr;
@UiField ListBox lbxEndTimeHr;
@UiField ListBox lbxStartTimeMi;
@UiField ListBox lbxEndTimeMi;
private final AppointmentServiceAsync appointService =
(AppointmentServiceAsync) GWT.create(AppointmentService.class);
private final ListVisitor visitors = new ArrayListVisitor();
public AppointmentCreateWidget() {
initWidget(uiBinder.createAndBindUi(this))
}
@UiHandler(btnSaveAppointment)
void onClick(ClickEvent e) {
addAppointment();
}
private void addAppointment() {
String subject = tbxSubject.getText().toUpperCase().trim();
Date startdate = dbAppointStartDate.getValue();
Date enddate = dbAppointEndDate.getValue();
String starttime =
lbxStartTimeHr.getValue(lbxStartTimeHr.getSelectedIndex()).toString()
+
lbxStartTimeMi.getValue(lbxStartTimeMi.getSelectedIndex());
String endtime =
lbxEndTimeHr.getValue(lbxEndTimeHr.getSelectedIndex()).toString() +
lbxEndTimeMi.getValue(lbxEndTimeMi.getSelectedIndex());
String room =
lbxRoom.getValue(lbxRoom.getSelectedIndex()).toString();
String key = lbxHost.getValue(lbxHost.getSelectedIndex());
DateTimeFormat dateFormat = DateTimeFormat.getShortDateFormat();
try {
createAppointment(subject, startdate, enddate,
starttime,
endtime, key, visitors);
}
catch(Exception ex) {
Window.alert(Save Appointment failed: + ex.toString());
}
}
private void createAppointment(String subject, Date startdate, Date
enddate, String starttime, String endtime, String empID, ListVisitor
visitor) {
appointService.addAppointment(subject,startdate, enddate,
starttime, endtime, empID, visitor, new AsyncCallbackVoid() {
public void onFailure(Throwable error) {
Window.alert(Unable to create Appointment. +
error.getMessage());
}
public void onSuccess(Void ignore) {
}
});
}
}
//ServiceImpl
public class AppointmentServiceImpl extends RemoteServiceServlet
implements AppointmentService {
/**
*
*/
private static final long serialVersionUID = 1L;
public void addAppointment(String subject, Date appointStartDate,
Date appointEndDate, String startTime, String endTime, String empID,
ListVisitor visitors) throws
[appengine-java] Not able to save child object in one-to-many relationship
I am trying to develop GAE application. I am using the latest GWT
SDK(2.0.4) AND App Engine SDK(1.3.6) on Eclipse3.4. I am having
problem in saving a child object Appointment and the parent object
is Employee. Each Employee has many appointments and and each
appointment has one employee associated with. I have pasted the Client
code and the server code here. Please help and see what I am missing
here. I tried many different ways without success. When I retrieve the
appointments, the employee is always null. I appreciate any help or
some example that I can try. Thanks.
//Client code
public class AppointmentCreateWidget extends Composite {
private static AppointmentCreateWidgetUiBinder uiBinder = GWT
.create(AppointmentCreateWidgetUiBinder.class);
interface AppointmentCreateWidgetUiBinder extends
UiBinderWidget, AppointmentCreateWidget {
}
@UiField Button btnSaveAppointment;
@UiField TextBox tbxSubject;
@UiField ListBox lbxRoom;
@UiField ListBox lbxHost;
@UiField DateBox dbAppointStartDate;
@UiField DateBox dbAppointEndDate;
@UiField ListBox lbxStartTimeHr;
@UiField ListBox lbxEndTimeHr;
@UiField ListBox lbxStartTimeMi;
@UiField ListBox lbxEndTimeMi;
private final AppointmentServiceAsync appointService =
(AppointmentServiceAsync) GWT.create(AppointmentService.class);
private final ListVisitor visitors = new ArrayListVisitor();
public AppointmentCreateWidget() {
initWidget(uiBinder.createAndBindUi(this))
}
@UiHandler(btnSaveAppointment)
void onClick(ClickEvent e) {
addAppointment();
}
private void addAppointment() {
String subject = tbxSubject.getText().toUpperCase().trim();
Date startdate = dbAppointStartDate.getValue();
Date enddate = dbAppointEndDate.getValue();
String starttime =
lbxStartTimeHr.getValue(lbxStartTimeHr.getSelectedIndex()).toString()
+
lbxStartTimeMi.getValue(lbxStartTimeMi.getSelectedIndex());
String endtime =
lbxEndTimeHr.getValue(lbxEndTimeHr.getSelectedIndex()).toString() +
lbxEndTimeMi.getValue(lbxEndTimeMi.getSelectedIndex());
String room =
lbxRoom.getValue(lbxRoom.getSelectedIndex()).toString();
String key = lbxHost.getValue(lbxHost.getSelectedIndex());
DateTimeFormat dateFormat = DateTimeFormat.getShortDateFormat();
try {
createAppointment(subject, startdate, enddate, starttime,
endtime, key, visitors);
}
catch(Exception ex) {
Window.alert(Save Appointment failed: + ex.toString());
}
}
private void createAppointment(String subject, Date startdate, Date
enddate, String starttime, String endtime, String empID, ListVisitor
visitor) {
appointService.addAppointment(subject,startdate, enddate,
starttime, endtime, empID, visitor, new AsyncCallbackVoid() {
public void onFailure(Throwable error) {
Window.alert(Unable to create Appointment. +
error.getMessage());
}
public void onSuccess(Void ignore) {
}
});
}
}
//ServiceImpl
public class AppointmentServiceImpl extends RemoteServiceServlet
implements AppointmentService {
/**
*
*/
private static final long serialVersionUID = 1L;
public void addAppointment(String subject, Date appointStartDate,
Date appointEndDate, String startTime, String endTime, String empID,
ListVisitor visitors) throws NotLoggedInException {
PersistenceManager pm = getPersistenceManager();
//get employee
Employee emp = pm.getObjectById(Employee.class, empID);
Appointment newAppoint = new Appointment(subject,
appointStartDate, appointEndDate, startTime, endTime);
newAppoint.setVisitors(visitors);
newAppoint.setEmployee(emp);
emp.getAppointments().add(newAppoint);
try {
pm.makePersistent(emp);
} finally {
pm.close();
}
}
private PersistenceManager getPersistenceManager() {
return PMF.get().getPersistenceManager();
}
}
//Employee Bean
@PersistenceCapable(identityType = IdentityType.APPLICATION,
detachable = true)
public class Employee implements IsSerializable, IValidatable {
@PrimaryKey
@Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
@Extension(vendorName=datanucleus, key=gae.encoded-pk,
value=true)
private String employeeKey;
@NotEmpty(message=You must specify First Name)
@Length(minimum=3)
@Persistent
private String firstName;
@NotEmpty(message=You must specify Last Name)
@Length(minimum=3)
@Persistent
private String lastName;
@Persistent
private String title;
@NotEmpty(message=You must specify Email Address)
@Length(minimum=3)
@Persistent
