JSF checkBox table validation ,check at least one

I have a Facelets page with a <table> (creating with <ui:repeat>). In each row of the <table> there is a <h:selectBooleanCheckbox>. I wanna add validation client have select at list one row. I use BalusC RequiredCheckboxValidator but, in that moment i have to click every checkbox in the page. Adding @Valid and @NotNull bean validation to map,not help either. How I can validate this?

<table >
<thead>
<tr>
 <td>chekboxes</td>
 ...
 </tr>
 </thead>                                            
 <tbody>
  <ui:repeat var="classroom" value="#{roomBean.classRooms}"> 
  <tr><td>
   <h:selectBooleanCheckbox value="#roomBean.checked[classroom.id]}"/>
</td>
 ...
</tr></ui:repeat>
</tbody>
</table>
<h:commandButton value="submit" action="#{bean.submit}" />

and

public class RoomBean{
private Map<Integer, Boolean> checked = new HashMap<Integer, Boolean>();
List<Integer> checkedClassRoomsID ;
//

public void submit() {
    checkedClassRoomsID = new ArrayList<>();
    for (ClassRoom classRoom : classRooms) {
        if (checked.get(classRoom.getId())) {
            checkedClassRoomsID.add(classRoom.getId());
        }
    }
 }
// ...
}