How to pass attributes to a composite-component - jsf-2

Question

I am having trouble in using a JSF composite-component in the right way. I put some components together and everything was working. Then I just extracted the code to a composite-component, and passed the corresponding attributes and suddenly I am getting conversation exceptions.
<composite:interface>
<composite:attribute name="selectedIDs" type="java.util.Collection" required="true"/>
<composite:attribute name="selectItems" type="java.util.List" required="true" />
<composite:attribute name="addAction" required="true"/>
<composite:attribute name="deleteAction" required="true"/>
<composite:attribute name="deleteButtonDisabled" />
<composite:attribute name="ajaxListener" method-signature="void listener(javax.faces.event.AjaxBehaviorEvent)"/>
</composite:interface>
<composite:implementation>
<div class="myClass">
<h:outputStylesheet library="views" name="selectManyControlPanel.css" target="head" />
<h:form>
<h:selectManyListbox value="#{cc.attrs.selectedIDs}">
<f:selectItems value="#{cc.attrs.selectItems}" />
<f:ajax render="delete"
listener="#{cc.attrs.ajaxListener}" />
</h:selectManyListbox>
<br />
<h:commandButton id="delete" value="Delete"
disabled="#{cc.attrs.deleteButtonDisabled}"
action="#{cc.attrs.deleteAction}" />
<h:commandButton id="add" value="Add" action="#{cc.attrs.addAction}"/>
</h:form>
</div>
</composite:implementation>
Here is the page where I am using the newly created component
<view:selectManyControlPanel
selectedIDs="#{bean.selectedIds}"
selectItems="#{bean.listOfSelectItems}"
addAction="#{bean.addNew}"
deleteAction="#{bean.deleteSelection}"
ajaxListener="#{bean.selectionChanged}"
deleteButtonDisabled="#{bean.deleteButtonDisabled}" />
Bean (some methods skipped an parts renamed)
package views;
#SuppressWarnings("serial")
#Named
#RequestScoped
public class Bean implements Serializable, IOverviewView {
#Inject
Presenter presenter;
private boolean deleteButtonDisabled;
private List<SelectItem> listOfSelectItems;
private Set<Long> selectedIds;
public Bean(){
deleteButtonDisabled = true;
listOfSelectItems = new ArrayList<SelectItem>(10);
}
public void selectionChanged(AjaxBehaviorEvent event){
if(selectedIds.isEmpty())
deleteButtonDisabled = true;
else
deleteButtonDisabled = false;
}
public void deleteBikes(){
presenter.delete(selectedIds);
}
public void addNew(){
presenter.addNew();
}
public List<SelectItem> getListOfSelectItems() {
return listOfSelectItems;
}
public Set<Long> getSelectedIds() {
return selectedIds;
}
#PostConstruct
public void init(){
System.out.println("INITIALIZING BEAN: " + this.getClass().getName());
this.presenter.setView(this);
this.presenter.init();
}
public boolean isDeleteButtonDisabled() {
return deleteButtonDisabled;
}
#Override
public void setDeleteButtonEnabled(boolean isEnabled) {
deleteButtonDisabled = !isEnabled;
}
public void setListOfSelectItems(List<SelectItem> list) {
this.listOfSelectItems = list;
}
public void setSelectedIds(Set<Long> selectedIds) {
this.selectedIds = selectedIds;
}
#Override
public void updateBikesList(Set<ViewObject> objectsToDisplay) {
updateList(objectsToDisplay);
}
private void updateList(Set<ViewObject> objectsToDisplay){
listOfSelectItems.clear();
for (ViewObject vO : objectsToDisplay) {
final String label = vO.getManufacturer() + ", " + vO.getModel() + " (" + vO.getYear() + ")";
listOfSelectItems.add(new SelectItem(vO.getId(), label));
}
}
....
}
Exception
javax.el.ELException: /resources/views/selectManyControlPanel.xhtml #25,56 value="#{cc.attrs.selectedIDs}": /index.xhtml #21,70 selectedIDs="#{bean.selectedIds}": Cannot convert [Ljava.lang.String;#1e92093 of type class [Ljava.lang.String; to interface java.util.Set
The only thing that changed is that I am using the composition instead of the plain code. The EL-expressions are still the same. Can someone enlighten me please? I expected that the parameters are just passed through but obviously not...

Answer 1

This is related to Mojarra issue 2047. It's scheduled to be fixed in the upcoming 2.2.
The issue ticket also proposes the following workaround:
<view:selectManyControlPanel
selectedIDsBean="#{bean}"
selectedIDsProperty="selectedIds"
with in CC interface
<composite:attribute name="selectedIDsBean" required="true"/>
<composite:attribute name="selectedIDsProperty" required="true"/>
and in CC implementation
<h:selectManyListbox value="#{cc.attrs.selectedIDsBean[cc.attrs.selectedIDsProperty]}">