(Java) Sign String to create a CAdES-T Signature

This example will sign a string to create a CAdEST-T signature.

Note: This example requires Chilkat v9.5.0.78 or greater.

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import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

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

    CkCrypt2 crypt = new CkCrypt2();

    // This example will use the certificate + private key currently inserted into a smartcard reader.
    CkCert cert = new CkCert();

    // If we wish to provide the smartcard PIN (otherwise the user will be prompted by the operating system).
    cert.put_SmartCardPin("000000");
    boolean success = cert.LoadFromSmartcard("");
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

    // Note: It is also possible to use certs from .pfx/.p12, .pem, or other sources such as 
    // pre-installed Windows certificates.

    success = crypt.SetSigningCert(cert);

    // Use SHA-256 rather than the default of SHA-1
    crypt.put_HashAlgorithm("sha256");

    // Create JSON that tells Chilkat what signing attributes to include:
    CkJsonObject attrs = new CkJsonObject();
    attrs.UpdateBool("contentType",true);
    attrs.UpdateBool("signingTime",true);
    attrs.UpdateBool("messageDigest",true);
    attrs.UpdateBool("signingCertificateV2",true);

    // A CAdES-T signature is one that includes a timestampToken created by an online TSA (time stamping authority).
    // We must include the TSA's URL, as well as a few options to indicate what is desired.
    // Except for the TSA URL, the options shown here are typically what you would need.
    attrs.UpdateBool("timestampToken.enabled",true);
    attrs.UpdateString("timestampToken.tsaUrl","https://freetsa.org/tsr");
    attrs.UpdateBool("timestampToken.addNonce",false);
    attrs.UpdateBool("timestampToken.requestTsaCert",true);
    attrs.UpdateString("timestampToken.hashAlg","sha256");

    crypt.put_SigningAttributes(attrs.emit());

    String strToSign = "THIS IS MY ID";

    CkBinData bd = new CkBinData();
    bd.AppendString(strToSign,"utf-8");

    // This creates the CAdES-T signature.  During the signature creation, it
    // communicates with the TSA to get a timestampToken.
    // The contents of bd are signed and replaced with the CAdES-T signature (which embeds the original content).
    success = crypt.OpaqueSignBd(bd);
    if (success != true) {
        System.out.println(crypt.lastErrorText());
        return;
        }

    // Get the signature in base64 format:
    System.out.println(bd.getEncoded("base64_mime"));

    // Or save the signature to a file.
    bd.WriteFile("qa_output/cades-t_sample.p7m");

    System.out.println("Success.");
  }
}