title: How to get total row number excel in java include row null?
body: <p>i'm have file .xls, into i ignore three Row and begin at row is three.</p>
  
  <p>Example: total number its is 20, i'm ignore three line, and begin modify with line 4, but I get row num (<code>sheet.getLastRowNum()</code> then is: 17, why not is 20? How to I can get all of line number?, in this case is 20.</p>