Java

Sign PDF with Long-Term Validation (LTV Enabled)

See more PDF Signatures Examples

This example demonstrates how to a sign a PDF with long-term validation (LTV) enabled.

Note: This example requires Chilkat v9.5.0.85 or greater.

Chilkat2 Java

import com.chilkatsoft.chilkat2.Cert;
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.JsonObject;
import com.chilkatsoft.chilkat2.Pdf;

public class ChilkatExample {

    public static void main(String[] args) {
        // This example requires the Chilkat API to have been previously unlocked.
        // See Global Unlock Sample for sample code.

        Pdf pdf = new Pdf();

        // Load a PDF to be signed.
        // The "hello.pdf" is available at https://chilkatsoft.com/hello.pdf
        try {
            pdf.loadFile("qa_data/pdf/hello.pdf");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Options for signing are specified in JSON.
        JsonObject json = new JsonObject();

        // In most cases, the signingCertificateV2 and signingTime attributes are required.
        json.updateInt("signingCertificateV2", 1);
        json.updateInt("signingTime", 1);

        // Add the "ltvOcsp" instruction to the JSON passed to SignPdf.
        // This is what causes Chilkat to create an LTV-enabled signature.
        //
        // If we are signing a PDF that already has signatures, then the existing signatures
        // are automatically verified, and Chilkat will do OCSP certificate status checking (if possible)
        // for those certs in existing signatures (including certs in the certificate chains)
        // that do not yet have a valid OCSP response in the DSS (Document Security Store).
        // Chilkat will add the OCSP responses to the /OCSPs in the Document Security Store (/DSS).
        // Also, and certificates from existing signatures not yet in the DSS are added to the /Certs
        // in the DSS.
        //
        // Also, the "ltvOcsp" causes Chilkat to add the pdfRevocationInfoArchival authenticated attribute
        // to the CMS signature.  The pdfRevocationInfoArchival attribute (1.2.840.113583.1.1.8)
        // contains OCSP responses and the CRL for the issuer of the signing certificate.
        // Therefore, Chilkat will send an OCSP request to the signing certificate's OCSP URl (if one exists)
        // and will download the CRL from the issuer certificate's CRL Distribution Point (if one exists).
        json.updateBool("ltvOcsp", true);

        // -----------------------------------------------------------------------------------
        // Note: If Chilkat produces a signed PDF, but the signature is not LTV-enabled,
        // the cause might be related to a failure to download CRL's or OCSP requests.
        // See Possible Solution for Failure to Produce LTV-enabled PDF Signature
        // -----------------------------------------------------------------------------------
        // You can add the following to UncommonOptions to get detailed information about the CRL and OCSP requests
        // You shouldn't set the following logging options unless there is a need, because it adds a large amount of information to the LastErrorText.
        pdf.setUncommonOptions("LOG_OCSP_HTTP,LOG_CRL_HTTP");

        // Define the appearance of the signature.
        json.updateInt("page", 1);
        json.updateString("appearance.y", "top");
        json.updateString("appearance.x", "left");
        json.updateString("appearance.fontScale", "10.0");
        json.updateString("appearance.text[0]", "Digitally signed by: cert_cn");
        json.updateString("appearance.text[1]", "current_dt");
        json.updateString("appearance.text[2]", "This is an LTV-enabled signature.");

        // Load the signing certificate. (Use your own certificate.)
        Cert cert = new Cert();
        try {
            cert.loadPfxFile("qa_data/pfx/myPdfSigningCert.pfx", "pfxPassword");

            // Tell the pdf object to use the certificate for signing.
            pdf.setSigningCert(cert);

            pdf.signPdf(json, "qa_output/hello_ltv_signed.pdf");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("The PDF has been successfully cryptographically signed with long-term validation.");

        // If you open the Signature Panel in Adobe Acrobat, it will indicate that the signature is LTV enabled
        // as shown here:
        // 
    }
}