How can I get PDVisibleSigProperties to write the signature on the 3 page into the signature box

Question

I am working with the pdfbox example signature CreateVisableSignature and I would like the code to write the image of the signature into a signature field called "ApplicantSignature" on the third page.

Can someone give a clue as to why it writes the signature in the upper left corner of the first page?

Here is the code:

    public static void main(String[] args) throws KeyStoreException,
        NoSuchAlgorithmException, CertificateException,
        FileNotFoundException, IOException, COSVisitorException,
        SignatureException {

    if (args.length != 4) {
        usage();
        System.exit(1);
    } else {
        File ksFile = new File(args[0]);
        KeyStore keystore = KeyStore.getInstance("PKCS12", provider);
        char[] pin = args[1].toCharArray();
        keystore.load(new FileInputStream(ksFile), pin);
        File document = new File(args[2]);
        CreateVisibleSignature signing = new CreateVisibleSignature(
                keystore, pin.clone());
        String jpgFile = CreateVisibleSignature.convertPngToJpeg( args[3] );
        FileInputStream image = new FileInputStream( jpgFile );
        PDVisibleSignDesigner visibleSig = new PDVisibleSignDesigner(
                args[2], image, 1);
        visibleSig.xAxis(0).yAxis(0).zoom(-75)
                .signatureFieldName("ApplicantSignature");
        PDVisibleSigProperties signatureProperties = new PDVisibleSigProperties();
        signatureProperties.signerName("name").signerLocation("location")
                .signatureReason("Security").preferredSize(0).page(3)
                .visualSignEnabled(true).setPdVisibleSignature(visibleSig)
                .buildSignature();
        signing.signPDF(document, signatureProperties);
    }
}

I have also tried:

    PDVisibleSignDesigner visibleSig = new PDVisibleSignDesigner(
                args[2], image, 3);
        visibleSig.xAxis(0).yAxis(0).zoom(-75)
                .signatureFieldName("ApplicantSignature");
        PDVisibleSigProperties signatureProperties = new PDVisibleSigProperties();
        signatureProperties.signerName("name").signerLocation("location")
                .signatureReason("Security").preferredSize(0).page(1)
                .visualSignEnabled(true).setPdVisibleSignature(visibleSig)
                .buildSignature();

And I have tried:

    PDVisibleSignDesigner visibleSig = new PDVisibleSignDesigner(
                args[2], image, 3);
        visibleSig.xAxis(0).yAxis(0).zoom(-75)
                .signatureFieldName("ApplicantSignature");
        PDVisibleSigProperties signatureProperties = new PDVisibleSigProperties();
        signatureProperties.signerName("name").signerLocation("location")
                .signatureReason("Security").preferredSize(0).page(3)
                .visualSignEnabled(true).setPdVisibleSignature(visibleSig)
                .buildSignature();

This is where I want the signature to go on the third page.

This is where it is going on the first page.

These are the field names in the form.

Answer 1

See this line in CreateVisibleSignature.java, in signPDF() (not included in your question, but part of the example code in PDFBox you mention):

// options.setPage(signatureProperties.getPage());

remove the "//" and the signature appears on page 3.

Re position, change this part of your code

xAxis(0).yAxis(0)

to other coordinates, e.g. these:

xAxis(100).yAxis(715)

Now about the question which code in the question is correct - the last one is:

PDVisibleSignDesigner visibleSig = new PDVisibleSignDesigner(args[2], image, 3);
visibleSig.xAxis(0).yAxis(0).zoom(-75).signatureFieldName("ApplicantSignature");
PDVisibleSigProperties signatureProperties = new PDVisibleSigProperties();
signatureProperties.signerName("name").signerLocation("location")
    .signatureReason("Security").preferredSize(0).page(3)
    .visualSignEnabled(true).setPdVisibleSignature(visibleSig)
    .buildSignature();

The 3 in PDVisibleSignDesigner is to choose the size of the page. The second 3 is to store the number of the page for later. The page numbers are 1-based here.