@Override
 public Map<String, String> getAllPropertiesString() {
   Map<String, String> ret = new HashMap<String, String>();
   for (Entry<String, Object> e : this.entrySet()) {
     if (!Attribute.isFinalAttribute(e.getKey())) {
       ret.put(e.getKey(), Util.toStringAttrValue(e.getValue()));
     }
   }
   return ret;
 }
 /**
  * Get the value of the property.
  *
  * <p>Attributes are supposed to be correct and inherited statically
  */
 @Override
 public String getProperty(String attr) {
   return Util.toStringAttrValue(getPropertyObject(attr));
 }