public DescribeCertificatesResult unmarshall(StaxUnmarshallerContext context) throws Exception {
    DescribeCertificatesResult describeCertificatesResult = new DescribeCertificatesResult();
    int originalDepth = context.getCurrentDepth();
    int targetDepth = originalDepth + 1;

    if (context.isStartOfDocument()) targetDepth += 2;

    while (true) {
      XMLEvent xmlEvent = context.nextEvent();
      if (xmlEvent.isEndDocument()) return describeCertificatesResult;

      if (xmlEvent.isAttribute() || xmlEvent.isStartElement()) {

        if (context.testExpression("Certificates/Certificate", targetDepth)) {
          describeCertificatesResult.withCertificates(
              CertificateStaxUnmarshaller.getInstance().unmarshall(context));
          continue;
        }

        if (context.testExpression("Marker", targetDepth)) {
          describeCertificatesResult.setMarker(
              StringStaxUnmarshaller.getInstance().unmarshall(context));
          continue;
        }
      } else if (xmlEvent.isEndElement()) {
        if (context.getCurrentDepth() < originalDepth) {
          return describeCertificatesResult;
        }
      }
    }
  }
 /**
  * An optional pagination token provided by a previous <a>DescribeCertificates</a> request. If
  * this parameter is specified, the response includes only records beyond the marker, up to the
  * value specified by <code>MaxRecords</code> .
  *
  * @param marker An optional pagination token provided by a previous <a>DescribeCertificates</a>
  *     request. If this parameter is specified, the response includes only records beyond the
  *     marker, up to the value specified by <code>MaxRecords</code> .
  * @return Returns a reference to this object so that method calls can be chained together.
  */
 public DescribeCertificatesResult withMarker(String marker) {
   setMarker(marker);
   return this;
 }