/**
    * Creates a deep copy clone of the FeatureTypeStyle.
    *
    * @see org.geotools.styling.FeatureTypeStyle#clone()
    */
   @Override
   public Object clone()
   {
      FeatureTypeStyle clone;

      try
      {
         clone = (FeatureTypeStyle) super.clone();
      }
      catch (final CloneNotSupportedException e)
      {
         throw new AssertionError(e); // this should never happen.
      }

      final List<Rule> rulesCopy = new ArrayList<Rule>();

      for (final Rule rl : rules)
      {
         rulesCopy.add((Rule) ((Cloneable) rl).clone());
      }

      ((FeatureTypeStyleImpl) clone).rules = new ArrayList<Rule>();
      ((FeatureTypeStyleImpl) clone).featureTypeNames = new LinkedHashSet<Name>();
      ((FeatureTypeStyleImpl) clone).semantics = new LinkedHashSet<SemanticType>();
      @SuppressWarnings("unchecked")
      final List<Rule> cloneRules = (List<Rule>) clone.rules();
      cloneRules.addAll(rulesCopy);
      clone.featureTypeNames().addAll(featureTypeNames);
      clone.semanticTypeIdentifiers().addAll(semantics);

      return clone;
   }