public static String rowIndexListToString ( final List < Integer > row ) { if ( row == null || row . isEmpty ( ) ) { return null ; } StringBuffer index = new StringBuffer ( ) ; boolean addDelimiter = false ; for ( Integer lvl : row ) { if ( addDelimiter ) { index . append ( INDEX_DELIMITER ) ; } index . append ( lvl ) ; addDelimiter = true ; } return index . toString ( ) ; }
Convert the row index to its string representation .