public void addUniqueAttribute(final String elementName,final String attrName){
  if ((elementName != null) && (attrName != null)) {
    _uniqueElementAttrMap.put(elementName,attrName);
  }
}

public void addUniqueAttribute ( final String elementName , final String attrName ) { if ( ( elementName != null ) && ( attrName != null ) ) { _uniqueElementAttrMap . put ( elementName , attrName ) ; } }
add unique attribute to the element which will force elements to be identical .
