public static boolean isIdentifierHelperChar(char ch){
  return ':' == ch || '.' == ch || '-' == ch || '_' == ch;
}

public static boolean isIdentifierHelperChar ( char ch ) { return ':' == ch || '.' == ch || '-' == ch || '_' == ch ; }
checks if specified character can be part of xml identifier ( tag name of attribute name ) and is not standard identifier character .
