I have a problem similar to the ones described here:
primefaces datatable not displaying anything
PrimeFaces DataTable "No records found" when there are records
my PrimeFaces datatable does not show any results, altough there are records in the database. Moreover: it seems that NO JAVA method is called when I request the page from the browser - at least the init() method of the backing bean seems not to be called at all
Where can the problem be? I would appreciate any help!
Thank you!
My template:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:p="http://primefaces.org/ui"
xmlns:c="http://java.sun.com/jsp/jstl/core">
<h:head>
<meta charset="UTF-8"/>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Bibliothek - Customers </title>
</h:head>
<h:body>
<h:form id="customersform">
<p:growl id="growl" life="2000" />
<p:panel header="All customers in the application" />
<p:dataTable id="customersTable" var="customer"
value="#{kundenBean.dataModel}" paginator="true" rows="10"
paginatorTemplate="{RowsPerPageDropdown} {FirstPageLink} {PreviousPageLink} {CurrentPageReport} {NextPageLink} {LastPageLink}"
resizableColumns="true" rowsPerPageTemplate="5,10,15"
selection="#{kundenBean.selektierterKunde}" selectionMode="single"
rowKey="#{customer.id}" lazy="true">
<p:column headerText="Customer's Name" style="width:332px;text-align:center"
sortBy="#{customer.vorname}" filterBy="#{customer.vorname}">
<h:outputText value="#{customer.vorname}" />
</p:column>
<p:column headerText="Customer's Address" sortBy="#{customer.adresse}"
filterBy="#{customer.adresse}">
<h:outputText value="#{customer.adresse}" />
</p:column>
</p:dataTable>
</h:form>
</h:body>
</html>
The Backing Bean:
@Named
@ViewScoped
public class KundenBean {
private Logger logger = Logger.getLogger(KundenBean.class.getName());
public static final String SELECTED_CUSTOMER = "selectedCustomer";
@Inject
private KundeDBService kundenDBService;
private LazyKundeDataModel dataModel;
private Kunde selektierterKunde;
private int selectedCustId;
@PostConstruct
private void init() {
this.dataModel = new LazyKundeDataModel(kundenDBService);
}
public LazyKundeDataModel getDataModel() {
return dataModel;
}
public void setDataModel(LazyKundeDataModel dataModel) {
this.dataModel = dataModel;
}
public Kunde getSelektierterKunde() {
return selektierterKunde;
}
public int getSelectedCustId() {
return selectedCustId;
}
public void setSelektierterKunde(Kunde selektierterKunde) {
this.selektierterKunde = selektierterKunde;
}
public void onRowSelect(SelectEvent event) {
selectedCustId = ((Kunde) event.getObject()).getId();
}
public void onRowDblClick(final SelectEvent event) {
selectedCustId = ((Kunde) event.getObject()).getId();
try {
ExternalContext extCtx = FacesContext.getCurrentInstance()
.getExternalContext();
extCtx.getFlash().put(SELECTED_CUSTOMER,((Kunde) event.getObject()));
FacesContext.getCurrentInstance().getExternalContext().redirect("rents.xhtml?custId=" +selectedCustId);
} catch (IOException e) {
e.printStackTrace();
logger.error(e.getMessage(), e);
}
}
}
The Data Model:
public class LazyKundeDataModel extends LazyDataModel<Kunde> {
private static final long serialVersionUID = 1L;
private KundeDBService kundeDBService;
public LazyKundeDataModel(KundeDBService kundeDBService) {
this.kundeDBService = kundeDBService;
}
@Override
public Kunde getRowData(String rowKey) {
return kundeDBService.getKundeById(Integer.valueOf(rowKey));
}
@Override
public Object getRowKey(Kunde kunde) {
return kunde.getId();
}
@Override
public List<Kunde> load(int first, int pageSize, String sortField, SortOrder sortOrder,
Map<String, Object> filters) {
List result = this.kundeDBService.load(first, pageSize, sortField, sortOrder, filters);
// rowCount
this.setRowCount(result.size());
this.setPageSize(pageSize);
return result;
}
}
The DB Service:
@Stateless
public class KundeDBService {
@PersistenceContext
private EntityManager em;
public static final String JOINING_OR = " OR ";
public static final String JOINING_AND = " AND ";
public static final String CONDITION_WHERE = " WHERE ";
private static Logger logger = Logger.getLogger(KundeDBService.class.getName());
public List<? extends Kunde> load(int first, int pageSize, String sortField, SortOrder sortOrder,
Map<String, Object> filters) {
List<? extends Kunde> result = new ArrayList<Kunde>();
String selectQUERY = " select k from Kunde k ";
if (filters.size() > 0) {
selectQUERY += addFiltersToQuery(filters);
}
if (sortField != null) {
selectQUERY += " order by k." + sortField;
if (sortOrder != null) {
selectQUERY += " " + (sortOrder);
}
}else { // sortField == null, default sort by customer's name
selectQUERY += " order by k.vorname asc";
}
Query emQuery = em.createQuery(selectQUERY);
emQuery.setFirstResult(first);
emQuery.setMaxResults(pageSize);
result = (List<Kunde>) emQuery.getResultList();
return result;
}
private String addFiltersToQuery(Map<String, Object> filters) {
if (filters.size() == 0)
return StringUtils.EMPTY;
StringBuilder whereCondition = new StringBuilder(CONDITION_WHERE);
int pseudoCounter = 0;
for (Entry<String, Object> entry : filters.entrySet()) {
whereCondition.append("k." + entry.getKey() + " LIKE :" + "x" + (++pseudoCounter));
whereCondition.append(JOINING_AND);
}
if (whereCondition.length() > CONDITION_WHERE.length()) {
whereCondition.delete(whereCondition.length() - JOINING_AND.length(), whereCondition.length());
}
return whereCondition.toString();
}
public Kunde getKundeById(int id) {
return em.find(Kunde.class, Integer.valueOf(id));
}
}
