Remove last empty line in XML generated by Jdom2

Question

I used getPrettyFormat() in Jdom2 and it gives me a XML file as below.

<?xml version="1.0" encoding="UTF-8"?>
   <courses>
      <name id="1">CynO</name>
   </courses>

My XML file generate 5 lines instead of 4. How to delete the fifth empty line?

My code:

XMLOutputter xml = new XMLOutputter();
xml.setFormat(Format.getPrettyFormat());
xml.output(doc, new FileWriter(fileName));