I have this Dao which get events according to the user id. It return the events object.
public enum Dao {
INSTANCE;
public List<EventsDetail> getevents(String userId) {
EntityManager em = EMFService.get().createEntityManager();
Query q = em.createQuery("select t from EventsDetail t where t.MemberId = :userId");
q.setParameter("userId", userId);
@SuppressWarnings("unchecked")
List<EventsDetail> events = q.getResultList();
return events;
}
}
here i have this jsp page which call dao as i have import the dao class. here i have used try and catch to throw exception where i get null pointer exception.
<%
Dao dao = Dao.INSTANCE;
UserService userService = UserServiceFactory.getUserService();
User user = userService.getCurrentUser();
List<EventsDetail> events = new ArrayList();
if (user != null) {
pageContext.setAttribute("user", user);
events = dao.getevents(user.getUserId());
%>
}....
<%
try{
for (EventsDetail event : events) {
pageContext.setAttribute("title", event.Title());
pageContext.setAttribute("place", event.getPlace());
pageContext.setAttribute("category", event.Category());
pageContext.setAttribute("cdate", event.Cdate());
%>
<div class="row">
<span class="r1"><%=count%></span>
<span class="r2">${fn:escapeXml(cdate)}</span>
<span class="r2">${fn:escapeXml(place)}</span>
<span class="r3">${fn:escapeXml(title)}</span>
<span class="r4">${fn:escapeXml(category)}</span>
</div>
<% }
} catch (Exception e)
{
System.out.println("Exception:" + e);
}
%>
the problem is that i get just empty data from the datastore where data are already persent in the datastore.
I think the problem is with your getEvents
method.
you can try doing the following:
public enum Dao {
INSTANCE;
public List<EventsDetail> getevents(String userId) {
EntityManager em = EMFService.get().createEntityManager();
Query q = em.createQuery("select t from EventsDetail t where t.MemberId = " + userId);
q.setParameter("userId", userId);
@SuppressWarnings("unchecked")
List<EventsDetail> events = q.getResultList();
return events;
}
}
and make sure you are passing correct userId.
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