I recently had a problem with jsf+hibernate, with another control from the
selectOneXXX family (see
http://forum.primefaces.org/viewtopic.php?f=3&t=27919#p88162 and later)
My problem was that I was comparing "real" objects and "hibernate proxy"
objects. The standard java equals function just fails in this case. I do not
see how you fetch your objects, but this might be the case.
Your problem might also be simplier. I am also a bit surprised that you return
a list of SelectItem as value for your f:selectItems.
Let say that you have a Student type.
You will then have a
List<Student> getStudentList()
method and a custom Converter to propertly manage the String <-> Object mapping.
Your selectedItem property should in this case also be of Student type.
------------------------
Thanks for sharing your thoughts.
I tried the backing bean to use String objects and List<String> for the list
box, since the studentId is a varchar(xx) type in the backend db. The same
problem exists, even now. That is, when only an entry is selected from the list
and the <Details> button pressed, the list empties in the jsf page, the jsf
page is refresed, and the "Detail1" function for the <Detail> button is not
being called. This function (Detail1) is called when the list is empty or when
no entry is selected from the list and the when the <Detail> button is pressed.
Everything works correctly when Jpa is used for data access in the backing
bean. Why is there the problem in the hibernate-jsf interaction?
*********************************************************
// Jsf
<h:outputLabel value="Teacher Name "/>
<h:inputText id="Student" value="#{studBean.teacherName}" size="20"
maxlength="50">
</h:inputText>
<h:selectOneListbox id="studentList"
value="#{studBean.selectedItem}"
size="5" >
<f:selectItems value="#{studBean.studentList}" />
</h:selectOneListbox>
<h:commandButton id="Select" action="#{studBean.studSel}" value="Select" />
<h:commandButton id="Details" action="#{studBean.Details1}" value="Details" />
*********************************************************
// Backing bean
@ManagedBean
@SessionScoped
public class StudBean implements Serializable {
private String teacherName;
private List<String> studentList;
private String selectedItem = null;
private String studentId;
// Getter and setter methods omitted
//
public String studSel() {
studentList = new ArrayList<String>();
List<String> cList = getStudentDetailForTeacher();
if(cList.isEmpty())
return null;
for (int i = 0; i < cList.size(); i++) {
String studentid = cList.get(i);
studentList.add(courseid);
}
return null;
}
public List<String[]> getStudentDetailForTeacher() {
this.session = HibernateUtil.getSessionFactory().getCurrentSession();
List<String[]> studentlist = null;
String strQuery = "select c.id.studentId "
+ "from TeacherStudent c WHERE c.id.teacherId = :teachid1";
org.hibernate.Transaction tx = session.beginTransaction();
Query cQuery = session.createQuery(strQuery);
// teacherName is in the jsf page tied to this backing bean member
variable
cQuery.setParameter("teachid1", teacherName);
studentlist = (List<String[]>) cQuery.list();
return studentlist;
}
public void studentCodeChanged(ValueChangeEvent e){
studentId = e.getNewValue().toString();
System.out.println("studentId = "+studentId);
}
public Boolean Details1() {
System.out.println("studentId id = "+studentId);
return null;
}
}
