title: rich:datatable rowspan issue
body: <p>I need to create a rich:dataTable (or even extended) with the following features:</p>
  
  <p>I have a class Company having a collection of Product objects. I want to show the following table:</p>
  
  <p><img src="https://imgur.com/l5ZfS.png" alt="alt text"></p>
  
  <p>I still have not figured out how to do this with a subtable (in all the examples I found the subTable has the exact same columns as the master table). Presumably, I need to play with rowspans in the first two columns, but I still have not found the way.</p>
  
  <p>Could someone provide a pseudo-code for this?</p>
  
  <p>Cheers!</p>
  
  <p><strong>UPDATE 1:</strong>
  I tried set the <strong>rowspan</strong> of the columns in the left as the size of the list or products, and then :</p>
  
  <ul>
  <li>if the products is empty (no products for the company yet), I print two columns. I do this conditionally by setting their <strong>rendered</strong> attribute to <strong>#{myFuncs:sizeOf(company.products)}</strong></li>
  <li>If the products are >= 1 then I iterate over them with <strong></strong> and inside that loop I insert two columns (one for product name and one for description), and for each product name column except the first one I set the <strong>breakBefore</strong> attribute to <strong>#{ !myFunc:firstProduct(company.products, product)}</strong>, which evaluates to true for all product names except the first one.</li>
  </ul>
  
  <p>Unfortunately, this did not work for me, because the columns inside the <strong>a4j:repeat</strong> do not appear at all - not because of the <strong>rendered</strong> tag. The loop is correct because if I print standard text else, it appears.</p>
  
  <p>Is there a way to achieve rowspan, or am I banging my head on the wall?</p>
  
  <p><strong>UPDATE 2:</strong>
  The issue is probably related to this <a href="http://blog.hibernate.org/11633.lace" rel="noreferrer">article</a>, indicating the differences between iteration components such as <strong>&lt; a4j:repeat></strong> and the tag <strong>&lt; c:forEach></strong>. The first takes place at rendering time, while the second one operates earlier, when JSF components are placed onto the component tree of the page.</p>
  
  <p>I tried to get the rich:columns outside the a4j:repeat and they get rendered (of course, not as expected, but they do).</p>