*/
    protected void calculatePageInfo() {
        int startWithOffset = start - offset;
        if (startWithOffset < 0) {
            startWithOffset = 0;
        }
        allPageCount = (int) ((allRecordCount - 1) / pageSize) + 1;
        existPrevPage = startWithOffset > 0;
        existNextPage = startWithOffset < (long) (allPageCount - 1) * (long) pageSize;
        currentPageNumber = start / pageSize + 1;

            }
        };
        qrList.allRecordCount = 100;
        qrList.calculatePageInfo();

        // start=10, offset=5, so startWithOffset = 10-5 = 5
        // currentPageNumber = start / pageSize + 1 = 10 / 20 + 1 = 1
        // existPrevPage = startWithOffset > 0 = 5 > 0 = true
        assertEquals(1, qrList.getCurrentPageNumber());
        assertTrue(qrList.isExistNextPage());