if (content == null) content = new ByteArrayInputStream("<eof/>".getBytes());
XMLEventReader eventReader = xmlInputFactory.createXMLEventReader(content);
try {
AmazonWebServiceResponse<T> awsResponse = new AmazonWebServiceResponse<T>();
StaxUnmarshallerContext unmarshallerContext = new StaxUnmarshallerContext(eventReader, response.getHeaders());
unmarshallerContext.registerMetadataExpression("ResponseMetadata/RequestId", 2, ResponseMetadata.AWS_REQUEST_ID);
unmarshallerContext.registerMetadataExpression("requestId", 2, ResponseMetadata.AWS_REQUEST_ID);
registerAdditionalMetadataExpressions(unmarshallerContext);
T result = responseUnmarshaller.unmarshall(unmarshallerContext);
awsResponse.setResult(result);