signer.sign(request, awsCredentials);
}
StaxResponseHandler<X> responseHandler = new com.amazonaws.services.simpledb.internal.SimpleDBStaxResponseHandler<X>(unmarshaller);
DefaultErrorResponseHandler errorResponseHandler = new DefaultErrorResponseHandler(exceptionUnmarshallers);
ExecutionContext executionContext = new ExecutionContext(requestHandlers);
return (X)client.execute(request, responseHandler, errorResponseHandler, executionContext);
}