title: JSTL choose not run
body: <p>I would print the first link. But the program print the second one always.
  I try to change <code>!= null</code> with <code>not empty</code> etc., but there is no change.</p>
  
  <p>I print my object <code>abstractAttrezzatura.insieme</code>, and <strong>it is not null and not empty</strong>, so why this code doesn't work??</p>
  
  <pre><code>    &lt;c:choose&gt;
      &lt;c:when test="${abstractAttrezzatura.insieme != null} "&gt;    
      &lt;a href="${urlInsieme}"&gt;${labelInsieme}  &lt;img src="${urlTorna}" align="top" height="30" width="30"/&gt;&lt;/a&gt;
  &lt;/c:when&gt;
  &lt;c:otherwise&gt;
      &lt;a href="${urlFoglioLavoro}"&gt;${labelFoglioLavoro}  &lt;img src="${urlTorna}" align="top" height="30" width="30"/&gt;&lt;/a&gt;
  &lt;/c:otherwise&gt;
  &lt;/c:choose&gt;
  </code></pre>
  
  <p><strong>Controller:</strong></p>
  
  <pre><code>@RequestMapping(value = "{id}", method = RequestMethod.GET)
  public String show(@PathVariable("id") final Long id, final Model uiModel, final Locale locale, 
          @ModelAttribute("idFoglioLavoro") Long idFoglioLavoro) {
      AbstractVerbale  verbale = verbaleService.findById(id);
      uiModel.addAttribute("verbale", verbale);
      uiModel.addAttribute("abstractAttrezzatura", verbale.getAttrezzatura());
      uiModel.addAttribute("itemId", verbale.getId());
      uiModel.addAttribute("idFoglioLavoro", idFoglioLavoro);
  
      return "verbale/show";
  }
  </code></pre>