d how to get Fully Qualified Name of duplicate fields in pdfbox

Question

File file = new File("E:/kamlesh/PdfBox/field name test.pdf");
PDDocument doc = PDDocument.load(file);
PDAcroForm form = doc.getDocumentCatalog().getAcroForm();
List<PDField> fields = form.getFields();
for (int i=0; i<fields.size(); i++) {
    PDField f = fields.get(i);
    System.out.println(f.getFullyQualifiedName());

}

output: its getting once if same field is used in multiple time.. need: if same field qualified name is coming mutiple time then display mutiple time..