Primefaces datatable onRowSelect method causing nullpointer exception - jsf-2

Question

I am using Hibernate 4, Spring 3 and JSF 2.0 with Weblogic 10.3.6 as server. I am loading my datatable using lazy loading.
JSF Page
<p:dataTable id="dataTable" var="req" lazy="true" value="#{emp.lazyModel}"
paginator="true" rows="10"
selection="#{emp.selectedRequest}"
selectionMode="single">
<p:ajax event="rowSelect" listener="#{emp.onRowSelect}" />
When I select a row in a datatable I am getting null pointer exception in onRowSelect method.
ManagedBean
public void onRowSelect(SelectEvent event) {
try {
this.setRequestNo(event.getObject().toString());
} catch (Exception e) {
e.printStackTrace();
}
}
In LazyEmpDataModel I have the following methods
#Override
public void setRowIndex(final int rowIndex) {
if (rowIndex == -1 || getPageSize() == 0) {
super.setRowIndex(-1);
} else {
super.setRowIndex(rowIndex % getPageSize());
}
}
#Override
public Object getRowKey(Employees emp) {
return request.getRequestNo();
}
#Override
public Employees getRowData(String rowKey) {
for (Employees emp : requestList) {
if (emp.getEmpNo().equals(rowKey))
return emp;
}
return null;
}
Full stackexception
java.lang.NullPointerException
at net.test.managed.bean.RequestManagedBean.onRowSelect(RequestManagedBean.java:134)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.sun.el.parser.AstValue.invoke(AstValue.java:187)
at com.sun.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:297)
at org.primefaces.component.behavior.ajax.AjaxBehaviorListenerImpl.processAjaxBehavior(AjaxBehaviorListenerImpl.java:52)
at org.primefaces.event.SelectEvent.processListener(SelectEvent.java:40)
at javax.faces.component.behavior.BehaviorBase.broadcast(BehaviorBase.java:106)
at javax.faces.component.UIComponentBase.broadcast(UIComponentBase.java:760)
at javax.faces.component.UIData.broadcast(UIData.java:1071)
at javax.faces.component.UIData.broadcast(UIData.java:1093)
at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794)
at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259)
at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)
at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:125)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:301)
at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:26)
at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
at weblogic.servlet.internal.RequestEventsFilter.doFilter(RequestEventsFilter.java:27)
at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3730)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3696)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120)
at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2273)
at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2179)
at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1490)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:256)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:221)

Answer 1

INMO its something with your view scope bean , try making it session... if session will help look for a way to work properly with CDI View bean
Maybe its being invalidated for some reason... Add a post constructor to your bean with print lines and see if its indeed being reconstructed upon pagination / row selection