code: public int getRowForLastPage() {
          Integer lastRow = internalGetLastRow();
          if(lastRow != null)
              return lastRow.intValue();
          else throw new IllegalStateException(Bundle.getErrorString("PagerModel_CantCalculateLastPage"));
      }
docs: Get the row used to display the last page.  This requires tha the data set size has been set via
  @return the row for the last page
  @throws IllegalStateException when the size of the data set has not been set