finding out required fields to fill in pdf file

Question

I\'m starting with new functionality in my android application which will help to fill certain PDF forms.

I find out that the best solution will be to use iText library.

Answer 1

Please take a look at section 13.3.4 of my book, entitled "AcroForms revisited". Listing 13.15 shows a code snippet from the InspectForm example that checks whether or not a field is a password or a multi-line field.

With some minor changes, you can adapt that example to check for required fields:

for (Map.Entry entry : fields.entrySet()) {
    out.write(entry.getKey());
    item = entry.getValue();
    dict = item.getMerged(0);
    flags = dict.getAsNumber(PdfName.FF);
    if (flags != null && (flags.intValue() & BaseField.REQUIRED) > 0)
        out.write(" -> required\n");
}