An Empirical Study on the Impact of Duplicate Code

Algorithm 2

An example of unstable duplicate code.

(a) Before Modification

 int offsetTmp = dataGridDisplayCriteria

     .getItemsPerPage() *

     (dataGridDisplayCriteria.getPage() -1);

  if (offsetTmp > 0) --offsetTmp;

  if (offsetTmp < 0) offsetTmp = 0;

 final int offset = offsetTmp;

  String sortColumn =

       dataGridDisplayCriteria.getSortColumn();

 Order orderTmp =

     dataGridDisplayCriteria.getOrder()

       .equals(AdServerBeansConstants.ASC) ?

           Order.asc(sortColumn)  :

              Order.desc(sortColumn);

(b) After 1st Modification

 int offsetTmp = dataGridDisplayCriteria

     .getItemsPerPage() *

         (dataGridDisplayCriteria.getPage() -1);

  if (offsetTmp > 0) --offsetTmp;

  if (offsetTmp < 0) offsetTmp = 0;

 final int offset = offsetTmp;

 String sortColumn =

%   dataGridDisplayCriteria.sortColumn;

 Order orderTmp =

%    dataGridDisplayCriteria.order

       .equals(AdServerBeansConstants.ASC) ?

          Order.asc(sortColumn)  :

             Order.desc(sortColumn);

(c) After 2nd Modification

 int offsetTmp = dataGridDisplayCriteria

     .getItemsPerPage() *

       (dataGridDisplayCriteria.getPage() -1);

#

  if (offsetTmp < 0) offsetTmp = 0;

 final int offset = offsetTmp;

 String sortColumn =

     dataGridDisplayCriteria.sortColumn;

 Order orderTmp =

     dataGridDisplayCriteria.order

     .equals(AdServerBeansConstants.ASC) ?

        Order.asc(sortColumn)  :

           Order.desc(sortColumn);