code: private StringBuilder replaceColumnsAndStripLastChar(String columnFamilyQuery, StringBuilder queryBuilder)
      {
          // strip last ",".
          if (queryBuilder.length() > 0)
          {
              queryBuilder.deleteCharAt(queryBuilder.length() - 1);
  
              columnFamilyQuery = StringUtils.replace(columnFamilyQuery, CQLTranslator.COLUMNS, queryBuilder.toString());
              queryBuilder = new StringBuilder(columnFamilyQuery);
          }
          return queryBuilder;
      }
docs: Strip last char.
  
  @param columnFamilyQuery
  the column family query
  @param queryBuilder
  the query builder
  @return the string builder