* @throws BadFieldValueException
* if category value not 'internal' or 'external'
*/
public void setCategoryValue(String category) throws BadFieldValueException {
if (category.equals("external") || category.equals("internal")) {
content.addProperty(new TextType(metadata, PDFAPROPPREFIX,
CATEGORY, category));
} else {
throw new BadFieldValueException(
"Unexpected value '"
+ category