问认证签名的LTV

EN

    public static void processDocumentLtv(String filePath) throws IOException, GeneralSecurityException, DocumentException {

    long startTime = System.currentTimeMillis();

    File original = new File(filePath);
    File temp = new File(filePath + ".ltv");

    PdfReader reader = new PdfReader(filePath);
    PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(temp), '\0', true);

    LtvVerification ltvVerification = stamper.getLtvVerification();
    OcspClient ocspClient = new OcspClientBouncyCastle();
    AcroFields fields = stamper.getAcroFields();
    List<String> signatureNames = fields.getSignatureNames();
    String sigName = signatureNames.get(signatureNames.size() - 1);
    PdfPKCS7 pkcs7 = fields.verifySignature(sigName);
    Certificate[] chain = pkcs7.getSignCertificateChain();
    X509Certificate x509certificate = pkcs7.getSigningCertificate();

    byte[] ocspResponse = ocspClient.getEncoded(x509certificate, CertificateUtils.getParent(x509certificate, chain), null);
    Collection<byte[]> crlBytes = CertificateUtils.fetchCrlBytes(x509certificate, chain);
    Collection<byte[]> ocspBytes = null;

    if (ocspResponse != null) {
        ocspBytes = new ArrayList<>();
        ocspBytes.add(ocspResponse);
    }

    ltvVerification.addVerification(sigName, ocspBytes, crlBytes, null);

    ltvVerification.merge();

    stamper.close();
    reader.close();

    Files.copy(temp.toPath(), original.toPath(), StandardCopyOption.REPLACE_EXISTING);
    temp.delete();

    logger.info("Took {}ms to do add the ltv information to the document.", (System.currentTimeMillis() - startTime));
}