/**
  * @param sizeUnit
  * @return
  */
 public static Unit getUnit(String sizeUnit) {
   Unit unit;
   if (!StringUtils.isEmpty(sizeUnit)) {
     unit = Unit.valueOf(sizeUnit);
   } else {
     unit = Unit.PX;
   }
   return unit;
 }
    @Override
    protected DockLayoutPanel instanciate(
        Class<? extends DockLayoutPanel> clazz, Map<String, Object> attributes, Object owner) {

      if (clazz == DockLayoutPanel.class) {
        String unit = (String) attributes.get("unit");
        Unit styleUnit = unit != null ? Unit.valueOf(unit) : Unit.PX;

        return new DockLayoutPanel(styleUnit);
      }

      // use default instanciation system
      return super.instanciate(clazz, attributes, owner);
    }