Question

What will happen if the EL expression like #{bean.list} is null. I’ve a nested datatable and the “value” of dataTable evaluates to null. In below example if issuerList is null, outer table footer is displayed but not the inner table. How does #{Issuer.issue} is handled considering “Issuer” is null !!!

Ex:

    <h:datatable value="#{bean.issuerList}" var="issuer" >
         ..  
      <h:datatable value="#{issuer.issueList}" var="issue" >
         ....
         ....
         <f:facet name="footer">
             This is inner footer
         </f:facet>
      </h:datatable>  
     <f:facet name="footer" >
          This is outer footer
     </f:facet>  
</h:datatable>   

Answer 1

If the #{bean.issuerList} is null then there are simply no rows to render. Since the nested datatable (and its footer) is part of a row, it’s also never rendered. You would need at least one row to get the nested datatable (and its footer) to render. The footer of the outer datatable is not part of any row, so it’s always rendered.