code: public static Comparator getComparator()
      {
          return new Comparator()
          {
              public int compare(Object o1, Object o2)
              {
                  FieldDescriptor fmd1 = (FieldDescriptor) o1;
                  FieldDescriptor fmd2 = (FieldDescriptor) o2;
                  if (fmd1.getColNo() < fmd2.getColNo())
                  {
                      return -1;
                  }
                  else if (fmd1.getColNo() > fmd2.getColNo())
                  {
                      return 1;
                  }
                  else
                  {
                      return 0;
                  }
              }
          };
      }
docs: returns a comparator that allows to sort a Vector of FieldMappingDecriptors
  according to their m_Order entries.