code: public <T extends AbstractJaxb> T copyNoException(Class<T> tagType) {
          T copy = null;
          try {
              copy = (T) this.copy(tagType);
          } catch (final TagTypeUnmatchException e) {
              return null;
          }
          return copy;
      }
docs: <p>
  same as {@link #copy(Class)} but never throw exception.
  return null if failed to copy.
  </p>
  
  @param tagType
  @return