title: Changing value of cell in Excel via apache-poi
body: <p>I'm trying to change value of cell in .xls document.</p>
  
  <p>In .xls file i have got only 1 cell - A1 with <code>abc</code> value inside.</p>
  
  <p>My code:</p>
  
  <pre><code>        File fo = new File("D:\\TMP\\Zeszyt1.xls");
          HSSFWorkbook a = new HSSFWorkbook(new FileInputStream(fo));
          HSSFSheet my_sheet = a.getSheetAt(0);
          HSSFRow my_row = my_sheet.getRow(0);
  
          HSSFCell myCell;
          myCell = my_row.getCell(0);
          myCell.setCellValue("NEW VALUE");
  </code></pre>
  
  <p>How to commit this changes? When i open .xls file i still have got <code>abc</code> value inside A1.</p>