(Java) Examine KeyInfo Certificate in XML Signature

This example loads signed XML and gets the signing certificate, assuming the certificate is contained in X509Certificate within the KeyInfo.

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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.

    CkXmlDSig dsig = new CkXmlDSig();
    CkStringBuilder sbXml = new CkStringBuilder();

    boolean success = sbXml.LoadFile("c:/aaworkarea/elias/3/face_f09006808443a699d1b.xml","utf-8");
    if (success != true) {
        System.out.println("Failed to load XML file.");
        return;
        }

    success = dsig.LoadSignatureSb(sbXml);
    if (success != true) {
        System.out.println(dsig.lastErrorText());
        return;
        }

    // Get the KeyInfo XML.
    CkXml xmlKeyInfo = dsig.GetKeyInfo();
    if (dsig.get_LastMethodSuccess() != true) {
        System.out.println(dsig.lastErrorText());
        return;
        }

    System.out.println(xmlKeyInfo.getXml());
    System.out.println("----");

    // Assuming the X509Certificate is in the KeyInfo, it will look like this:

    //   <ds:KeyInfo Id="...">
    //     <ds:KeyValue>
    //     ...  
    //     <ds:X509Data>
    //       <ds:X509Certificate>MIIHAz...</ds:X509Certificate>
    //     </ds:X509Data>
    //   </ds:KeyInfo>
    String certBase64 = xmlKeyInfo.getChildContent("*:X509Data|*:X509Certificate");
    if (xmlKeyInfo.get_LastMethodSuccess() != true) {
        System.out.println("No X509Certificate found in the KeyInfo.");
        return;
        }

    // Load a certificate object w/ the base64.
    CkCert cert = new CkCert();
    success = cert.LoadFromBase64(certBase64);
    if (success != true) {
        System.out.println(cert.lastErrorText());
        return;
        }

    // Examine the cert..
    System.out.println("SubjectDN: " + cert.subjectDN());
    System.out.println("IssuerDN: " + cert.issuerDN());
    System.out.println("SerialNumber as Decimal: " + cert.serialDecimal());
  }
}