@Override
    public java.util.concurrent.Future<UpdateSigningCertificateResult> updateSigningCertificateAsync(UpdateSigningCertificateRequest request) {

        return updateSigningCertificateAsync(request, null);
    }
Simplified method form for invoking the ListVirtualMFADevices operation with an AsyncHandler.

@see #listVirtualMFADevicesAsync(ListVirtualMFADevicesRequest, com.amazonaws.handlers.AsyncHandler)
aws-java-sdk-iam/src/main/java/com/amazonaws/services/identitymanagement/AmazonIdentityManagementAsyncClient.java