* @throws IOException If there is an error when exporting the document.
*/
public FDFDocument exportFDF() throws IOException
{
FDFDocument fdf = new FDFDocument();
FDFCatalog catalog = fdf.getCatalog();
FDFDictionary fdfDict = new FDFDictionary();
catalog.setFDF( fdfDict );
List fdfFields = new ArrayList();
List fields = getFields();
Iterator fieldIter = fields.iterator();
while( fieldIter.hasNext() )