Hello every one.

I have a problem with my <rich:picklist> and I wonder If somebody could help.
when executing the application I got the following error:

javax.ejb.EJBException
 at com.sun.ejb.containers.BaseContainer.processSystemException(BaseContainer.java:3869)
 at com.sun.ejb.containers.BaseContainer.completeNewTx(BaseContainer.java:3769)
...
 at org.richfaces.renderkit.html.PickListRendererGen.doEncodeChildren(PickListRendererGen.java:344)
 at org.richfaces.renderkit.html.PickListRendererGen.doEncodeChildren(PickListRendererGen.java:258)
....
Caused by: java.lang.NullPointerException
 at com.pingwy.daiki.management.action.AdminActionBean.selectCompanyNamesOption(AdminActionBean.java:149)
 at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
....

@Stateful
@Name("adminAction")
@Scope(ScopeType.SESSION)
public class AdminActionBean implements AdminActionLocal {

 @Out(required=false)
 private List<Customer> companyNames;

 @In(required=false)
 private List<Customer> customersChoice;

 @Out(required=false)
 private ArrayList<SelectItem> companyNamesOption;

@Factory("companyNames")
 public void selectCompanyNames(){
 setCompanyNames((List<Customer>) getEm().createQuery("select c from Customer c")
 .getResultList());
 }
 @Factory("companyNamesOption")
 public void selectCompanyNamesOption(){
 for (int i=0;i <companyNames.size();i++){
 companyNamesOption.add(new SelectItem(companyNames.get(i), companyNames.get(i).getCompanyName(), companyNames.get(i).getCompanyName() ) );
 }
 }

// getter and setter

<rich:pickList id="customersChoice" value="#{adminAction.customersChoice}">
 <f:selectItems value="#{companyNamesOption}" />
 </rich:pickList>