title: getRow() and getLastCellNum() of POI API
body: <p>I am working with Excel (xlsx) in Java. I never understood the return value type 
  from <code>getRow(int RowNum)</code>. What do you mean by "IT RETURNS THE LOGICAL ROW (0-Based)"? See below code.</p>
  
  <pre><code>row=sheet.getRow(0);
  </code></pre>
  
  <p>I am trying to get the data from 3rd row, 1st col. Apparently it worked and I got the
  result what I need (only after writing bit of further code).     </p>
  
  <p>But, my question is how user manage to get data from 3rd row? when the rownum is
  given as 0 (as you can see). I am expecting that it will (row) stick to 0th row ie. first row in Excel sheet.</p>
  
  <p><code>getLastCellNum()</code> method of XSSFRow class - what do you mean by "Gets the index of the last cell contained in this row PLUS ONE"?.</p>