code: public FieldDescriptor getFieldDescriptorForPath(String aPath, Map pathHints)
      {
          ArrayList desc = getAttributeDescriptorsForPath(aPath, pathHints);
          FieldDescriptor fld = null;
          Object temp;
  
          if (!desc.isEmpty())
          {
              temp = desc.get(desc.size() - 1);
              if (temp instanceof FieldDescriptor)
              {
                  fld = (FieldDescriptor) temp;
              }
          }
          return fld;
      }
docs: return the FieldDescriptor for the Attribute referenced in the path<br>
  the path may contain simple attribut names, functions and path expressions
  using relationships <br>
  ie: name, avg(price), adress.street
  @param aPath the path to the attribute
  @param pathHints a Map containing the class to be used for a segment or <em>null</em>
  if no segment was used.
  @return the FieldDescriptor or null (ie: for m:n queries)