title: How to add Data validation to entire column of an excel sheet using apache poi in java?
body: <p>I have a requirement Where I need to add data validation to an entire column rather than a specific cell. I went through the documentation of Apache poi and found the example below</p>
  
  <pre><code>HSSFWorkbook workbook = new HSSFWorkbook();
  HSSFSheet sheet = workbook.createSheet("Data Validation");
  CellRangeAddressList addressList = new CellRangeAddressList(0, 0, 0, 0);
  DVConstraint dvConstraint = DVConstraint.createExplicitListConstraint(
          new String[]{"10", "20", "30"});
  DataValidation dataValidation = new HSSFDataValidation
          (addressList, dvConstraint);
  dataValidation.setSuppressDropDownArrow(false);
  sheet.addValidationData(dataValidation);
  </code></pre>
  
  <p>But the above example creates a drop down datavalidation for a specific cell. In this case row 0, column 0. The rest of the cells in a column doesn't have validation. But in actual excel file we can do it so it should be possible. I tried and searched a lot but could not come to a solution. Please help..</p>