/**
* This method determines if the given field is a button.
*
* @param field the field to determine
* @return the result of the determination
* @throws IOException If there is an error determining the field type.
*/
private static boolean isButton(PDField field) throws IOException {
String ft = field.findFieldType();
boolean retval = FIELD_TYPE_BTN.equals(ft);
List kids = field.getKids();
if (ft == null && kids != null && kids.size() > 0) {
// sometimes if it is a button the type is only defined by one
// of the kids entries
Object obj = kids.get(0);
COSDictionary kidDict = null;
if (obj instanceof PDField) {
kidDict = ((PDField) obj).getDictionary();
} else if (obj instanceof PDAnnotationWidget) {
kidDict = ((PDAnnotationWidget) obj).getDictionary();
} else {
throw new IOException("Error:Unexpected type of kids field:" + obj);
}
retval = isButton(new PDUnknownField(field.getAcroForm(), kidDict));
}
return retval;
}
