public Response process()

in ch-sxmp/src/main/java/com/cloudhopper/sxmp/SxmpSession.java [64:134]
41 lines of code
12 McCabe index (conditional complexity)

    public Response process(InputStream is) throws IOException, SAXException, ParserConfigurationException {
        // create a new XML parser
        SxmpParser parser = new SxmpParser(version);

        // an instance of an operation we'll be processing as a request
        Operation operation = null;

        try {
            // parse input stream into an operation (this may
            operation = parser.parse(is);
        } catch (SxmpParsingException e) {
            // major issue parsing the request into something valid -- this
            // exception may contain a partially parsed operation -- if it does
            // then we want to return valid XML back to the caller of this session
            // don't dump stack trace; instead just log error message and what of the operation we parsed
            if (e.getOperation() != null && e.getOperation().getType() != null) {
                logger.warn("Unable to fully parse XML into a request, returning ErrorResponse; error: "+e.getMessage()+", parsed: "+e.getOperation());
                // we'll actually return a generic ErrorResponse back
                return new ErrorResponse(e.getOperation().getType(), e.getErrorCode().getIntValue(), e.getErrorMessage());
            } else {
                // otherwise, we should just return a generic error since nothing
                // really was parsed in the XML document
                throw new SAXException(e.getMessage(), e);
            }
        }

        // at this point, we'll catch any SxmpErrorExceptions and make sure they
        // are always converted into an ErrorResponse object, rather than
        // the exception ever being thrown
        try {
            // can only handle requests
            if (!(operation instanceof Request)) {
                throw new SxmpErrorException(SxmpErrorCode.UNSUPPORTED_OPERATION, "A session can only process requests");
            }

            // convert to a request
            Request req = (Request)operation;

            // was an account included?
            if (req.getAccount() == null) {
                throw new SxmpErrorException(SxmpErrorCode.MISSING_REQUIRED_ELEMENT, "A request must include account credentials");
            }

            // authenticate the request
            if (!processor.authenticate(req.getAccount())) {
                throw new SxmpErrorException(SxmpErrorCode.AUTHENTICATION_FAILURE, "Authentication failure");
            }

            // handle request type
            if (operation instanceof SubmitRequest) {
                return processor.submit(req.getAccount(), (SubmitRequest)operation);
            } else if (operation instanceof DeliverRequest) {
                return processor.deliver(req.getAccount(), (DeliverRequest)operation);
            } else if (operation instanceof DeliveryReportRequest) {
                return processor.deliveryReport(req.getAccount(), (DeliveryReportRequest)operation);
            } else {
                // if we got here, then a request we don't support occurred
                throw new SxmpErrorException(SxmpErrorCode.UNSUPPORTED_OPERATION, "Unsupported operation request type");
            }
        } catch (SxmpErrorException e) {
            // because this is a mostly normal error in the course of processing a message
            // we don't want to print the full stacktrace -- we just want to print the message
            logger.warn(e.getMessage());
            // we'll actually return a generic ErrorResponse back
            return new ErrorResponse(operation.getType(), e.getErrorCode().getIntValue(), e.getErrorMessage());
        } catch (Throwable t) {
            logger.error("Major uncaught throwable while processing request, generating an ErrorResponse", t);
            // we'll actually return a generic ErrorResponse back
            return new ErrorResponse(operation.getType(), SxmpErrorCode.GENERIC.getIntValue(), "Generic error while processing request");
        }
    }