Example usage for javax.servlet.http HttpServletResponse SC_PRECONDITION_FAILED

List of usage examples for javax.servlet.http HttpServletResponse SC_PRECONDITION_FAILED

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In this page you can find the example usage for javax.servlet.http HttpServletResponse SC_PRECONDITION_FAILED.

Prototype

int SC_PRECONDITION_FAILED

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Document

Status code (412) indicating that the precondition given in one or more of the request-header fields evaluated to false when it was tested on the server.

Usage

From source file:au.org.ala.biocache.web.DownloadController.java

/**
 * Add a download to the offline queue//from  w  ww  . j a  v a 2 s . c  o  m
 * @param requestParams
 * @param ip
 * @param apiKey
 * @param type
 * @param response
 * @param request
 * @return
 * @throws Exception
 */
@RequestMapping(value = "occurrences/offline/{type}/download*", method = RequestMethod.GET)
public String occurrenceDownload(DownloadRequestParams requestParams,
        @RequestParam(value = "ip", required = false) String ip,
        @RequestParam(value = "apiKey", required = false) String apiKey, @PathVariable("type") String type,
        HttpServletResponse response, HttpServletRequest request) throws Exception {

    boolean sensitive = false;
    if (apiKey != null) {
        if (shouldPerformOperation(apiKey, response, false)) {
            sensitive = true;
        }
    } else if (StringUtils.isEmpty(requestParams.getEmail())) {
        response.sendError(HttpServletResponse.SC_PRECONDITION_FAILED,
                "Unable to perform an offline download without an email address");
    }

    ip = ip == null ? request.getRemoteAddr() : ip;
    DownloadType downloadType = "index".equals(type.toLowerCase()) ? DownloadType.RECORDS_INDEX
            : DownloadType.RECORDS_DB;
    //create a new task
    DownloadDetailsDTO dd = new DownloadDetailsDTO(requestParams, ip, downloadType);
    dd.setIncludeSensitive(sensitive);

    persistentQueueDAO.addDownloadToQueue(dd);
    return null;
}

From source file:com.almende.eve.transport.http.EveServlet.java

/**
 * Handle hand shake./*from  w  w  w .  j  a v a 2 s  . co m*/
 * 
 * @param req
 *            the req
 * @param res
 *            the res
 * @return true, if successful
 * @throws IOException
 *             Signals that an I/O exception has occurred.
 */
private boolean handleHandShake(final HttpServletRequest req, final HttpServletResponse res)
        throws IOException {
    final String time = req.getHeader("X-Eve-requestToken");

    if (time == null) {
        return false;
    }
    final String url = req.getRequestURI();
    final String id = getId(url);
    final HttpTransport transport = HttpService.get(myUrl, id);
    if (transport != null) {
        final String token = transport.getTokenstore().get(time);
        if (token == null) {
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED);
        } else {
            res.setHeader("X-Eve-replyToken", token);
            res.setStatus(HttpServletResponse.SC_OK);
            res.flushBuffer();
        }
    }
    return true;
}

From source file:org.dataconservancy.dcs.util.http.RequestHeaderUtil.java

/**
 *
 * @param req - the HttpServletRequest//from  w w w. ja  v  a2  s .  c  o m
 * @param res - the HttpServletResponse
 * @param ifMatch  - the match string
 * @param requestUtil - the request util
 * @param objectToMatch - the object to match
 * @param objectToMatchEtag - the etag to match
 * @param objectToMatchId - the id to match
 * @param objectToMatchClassname - the class name to match
 * @return true if the response has been committed
 * @throws java.io.IOException an IO exception
 */
public boolean handleIfMatch(HttpServletRequest req, HttpServletResponse res, RequestUtil requestUtil,
        String ifMatch, Object objectToMatch, String objectToMatchEtag, String objectToMatchId,
        String objectToMatchClassname) throws IOException {

    if (ifMatch == null || ifMatch.trim().length() == 0) {
        return false;
    }

    if (objectToMatch == null) {
        if (ifMatch.contains("*")) {
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED, "Unable to resolve "
                    + objectToMatchClassname + " '" + requestUtil.buildRequestUrl(req) + "'");
        }

        return true;
    }

    // Split the values
    String[] ifMatchValues = ifMatch.split(",");
    boolean match = false;
    for (String ifMatchValue : ifMatchValues) {
        ifMatchValue = ifMatchValue.trim();
        if (ifMatchValue.equals("*") || ifMatchValue.equals(objectToMatchEtag)) {
            match = true;
        }
    }

    if (!match) {
        res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED,
                "If-Match header '" + ifMatch + "' " + "did not match the requested " + objectToMatchClassname
                        + " representation: '" + objectToMatchId + "' ('" + objectToMatchEtag + "')");
        return true;
    }

    return false;
}

From source file:com.almende.eve.transport.http.DebugServlet.java

/**
 * Handle hand shake./*  w  ww  .ja  v  a 2s . c  om*/
 * 
 * @param req
 *            the req
 * @param res
 *            the res
 * @return true, if successful
 * @throws IOException
 *             Signals that an I/O exception has occurred.
 */
private boolean handleHandShake(final HttpServletRequest req, final HttpServletResponse res)
        throws IOException {
    final String time = req.getHeader("X-Eve-requestToken");

    if (time == null) {
        return false;
    }

    final String url = req.getRequestURI();
    final String id = getId(url);
    final HttpTransport transport = HttpService.get(myUrl, id);
    if (transport != null) {
        final String token = transport.getTokenstore().get(time);
        if (token == null) {
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED);
        } else {
            res.setHeader("X-Eve-replyToken", token);
            res.setStatus(HttpServletResponse.SC_OK);
            res.flushBuffer();
        }
    }
    return true;
}

From source file:org.apache.sling.launchpad.webapp.integrationtest.servlets.post.PostServletCopyTest.java

public void testCopyNodeAbsoluteBelowDest() throws IOException {
    final String testPath = TEST_BASE_PATH + "/abs/" + System.currentTimeMillis();
    Map<String, String> props = new HashMap<String, String>();
    props.put("text", "Hello");
    testClient.createNode(HTTP_BASE_URL + testPath + "/src", props);

    // first test: failure because dest (parent) does not exist
    List<NameValuePair> nvPairs = new ArrayList<NameValuePair>();
    nvPairs.add(new NameValuePair(SlingPostConstants.RP_OPERATION, SlingPostConstants.OPERATION_COPY));
    nvPairs.add(new NameValuePair(SlingPostConstants.RP_DEST, testPath + "/dest/"));
    assertPostStatus(HTTP_BASE_URL + testPath + "/src", HttpServletResponse.SC_PRECONDITION_FAILED, nvPairs,
            "Expecting Copy Failure (dest must exist)");

    // create dest as parent
    testClient.createNode(HTTP_BASE_URL + testPath + "/dest", null);

    // copy now succeeds to below dest
    assertPostStatus(HTTP_BASE_URL + testPath + "/src", HttpServletResponse.SC_CREATED, nvPairs,
            "Expecting Copy Success");

    // assert content at new location
    String content = getContent(HTTP_BASE_URL + testPath + "/dest.-1.json", CONTENT_TYPE_JSON);
    assertJavascript("Hello", content, "out.println(data.src.text)");

    // assert content at old location
    content = getContent(HTTP_BASE_URL + testPath + "/src.json", CONTENT_TYPE_JSON);
    assertJavascript("Hello", content, "out.println(data.text)");
}

From source file:org.apache.sling.launchpad.webapp.integrationtest.servlets.post.PostServletMoveTest.java

public void testMoveNodeAbsoluteBelowDest() throws IOException {
    final String testPath = TEST_BASE_PATH + "/abs/" + System.currentTimeMillis();
    Map<String, String> props = new HashMap<String, String>();
    props.put("text", "Hello");
    testClient.createNode(HTTP_BASE_URL + testPath + "/src", props);

    // first test: failure because dest (parent) does not exist
    List<NameValuePair> nvPairs = new ArrayList<NameValuePair>();
    nvPairs.add(new NameValuePair(SlingPostConstants.RP_OPERATION, SlingPostConstants.OPERATION_MOVE));
    nvPairs.add(new NameValuePair(SlingPostConstants.RP_DEST, testPath + "/dest/"));
    assertPostStatus(HTTP_BASE_URL + testPath + "/src", HttpServletResponse.SC_PRECONDITION_FAILED, nvPairs,
            "Expecting Move Failure (dest must exist)");

    // create dest as parent
    testClient.createNode(HTTP_BASE_URL + testPath + "/dest", null);

    // move now succeeds to below dest
    assertPostStatus(HTTP_BASE_URL + testPath + "/src", HttpServletResponse.SC_CREATED, nvPairs,
            "Expecting Move Success");

    // assert content at new location
    String content = getContent(HTTP_BASE_URL + testPath + "/dest.-1.json", CONTENT_TYPE_JSON);
    assertJavascript("Hello", content, "out.println(data.src.text)");

    // assert content at old location
    assertHttpStatus(HTTP_BASE_URL + testPath + "/src.json", HttpServletResponse.SC_NOT_FOUND);
}

From source file:org.sakaiproject.nakamura.resource.lite.servlet.post.operations.ImportOperation.java

@Override
protected void doRun(SlingHttpServletRequest request, HtmlResponse response, ContentManager contentManager,
        final List<Modification> changes, String contentPath)
        throws StorageClientException, AccessDeniedException, IOException {

    Resource resource = request.getResource();
    String path = null;/*w  w w.j a  v a2 s  . c o m*/
    {
        Content content = resource.adaptTo(Content.class);
        if (content != null) {
            path = content.getPath();
        } else {
            // for some reason, if the operation posts to a path that does not exist and the
            // operation is create tree the SparseCreateServlet.doPost() operation is
            // bypassed. This is an ugly fix that works wound that problem. I suspect
            // somethings up in Sling.
            path = (String) request.getAttribute(SparseCreateServlet.CONTENT_TARGET_PATH_ATTRIBUTE);
        }
    }
    if (path == null) {
        throw new StorageClientException("No Path suppleid to create json tree at");
    }

    String contentType = request.getParameter(SlingPostConstants.RP_CONTENT_TYPE);
    if (contentType == null) {
        response.setStatus(HttpServletResponse.SC_PRECONDITION_FAILED,
                "Required :contentType parameter is missing");
        return;
    }

    // import options passed as request parameters.
    final boolean replace = "true".equalsIgnoreCase(request.getParameter(SlingPostConstants.RP_REPLACE));
    final boolean replaceProperties = "true"
            .equalsIgnoreCase(request.getParameter(SlingPostConstants.RP_REPLACE_PROPERTIES));
    final boolean removeTree = "true".equalsIgnoreCase(request.getParameter(":removeTree"));

    String basePath = getItemPath(request);
    if (basePath.endsWith("/")) {
        // remove the trailing slash
        basePath = basePath.substring(0, basePath.length() - 1);
    }

    response.setCreateRequest(true);

    try {
        InputStream contentStream = null;
        String content = request.getParameter(SlingPostConstants.RP_CONTENT);
        if (content == null) {
            RequestParameter contentFile = request.getRequestParameter(SlingPostConstants.RP_CONTENT_FILE);
            if (contentFile != null) {
                contentStream = contentFile.getInputStream();
                content = IOUtils.toString(contentStream, "UTF-8");
            }
        }

        if (content == null) {
            response.setStatus(HttpServletResponse.SC_PRECONDITION_FAILED, "Missing content for import");
            return;
        } else {

            JSONObject json = new JSONObject(content);
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("to {} importing {} ", basePath, json.toString(3));
            }
            LiteJsonImporter simpleJsonImporter = new LiteJsonImporter();
            Session session = StorageClientUtils
                    .adaptToSession(request.getResourceResolver().adaptTo(javax.jcr.Session.class));
            AccessControlManager accessControlManager = session.getAccessControlManager();
            simpleJsonImporter.importContent(contentManager, json, basePath, replace, replaceProperties,
                    removeTree, accessControlManager);
            response.setLocation(externalizePath(request, basePath));
            response.setPath(basePath);
            int lastSlashIndex = basePath.lastIndexOf('/');
            if (lastSlashIndex != -1) {
                String parentPath = basePath.substring(0, lastSlashIndex);
                response.setParentLocation(externalizePath(request, parentPath));
            }
        }

    } catch (IOException e) {
        LOGGER.error(e.getMessage(), e);
        throw new StorageClientException(e.getMessage(), e);
    } catch (JSONException e) {
        LOGGER.error(e.getMessage(), e);
        throw new StorageClientException(e.getMessage(), e);
    }
}

From source file:io.github.gsteckman.rpi_rest.SubscriptionManager.java

/**
 * Processes a UPnP SUBSCRIBE request and creates or renews a subscription.
 * /*from w ww .ja  va 2 s .c  om*/
 * @param key
 *            The key identifies the resource to which this subscription applies.
 * @param req
 *            Subscription request
 * @param res
 *            Response to the subscription request
 * @throws IOException
 *             Thrown by HttpServletResponse.sendError if an error occurs writing the response.
 */
public void processSubscribe(String key, HttpServletRequest req, HttpServletResponse res) throws IOException {
    String timeoutHdr = req.getHeader("TIMEOUT");
    String callbackHdr = req.getHeader("CALLBACK");
    String sidHdr = req.getHeader("SID");
    List<URL> callbackUrls = new LinkedList<URL>();

    // Perform error checking:
    // 1. Method must be SUBSCRIBE
    // 2. If no SID header
    // a. CALLBACK header must be present & properly formatted as a correct URL
    // b. NT header must be present with a value of "upnp:event"
    // 3. If there is a SID header, CALLBACK and NT headers not present
    if (!"SUBSCRIBE".equalsIgnoreCase(req.getMethod())) {
        // Return 405 status
        res.sendError(HttpServletResponse.SC_METHOD_NOT_ALLOWED,
                "Method " + req.getMethod() + " not allowed for this resource.");
        return;
    }

    if (sidHdr != null && (timeoutHdr != null || callbackHdr != null)) {
        res.sendError(HttpServletResponse.SC_BAD_REQUEST,
                "An SID header field and one of NT or CALLBACK header fields are present.");
        return;
    } else {
        if (callbackHdr == null) {
            // CALLBACK is a required header. Return status 412
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED, "CALLBACK header is missing.");
            return;
        } else {
            // parse callback header and ensure proper format
            callbackUrls = parseCallbackHeader(callbackHdr);
            if (callbackUrls.size() == 0) {
                res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED,
                        "CALLBACK header doesn't contain a valid HTTP URL.");
                return;
            }
        }

        if (!"upnp:event".equals(req.getHeader("NT"))) {
            // NT is a required header. Return status 412
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED,
                    "NT header field does not equal upnp:event.");
            return;
        }
    }

    // parse timeout header
    long timeout = DEFAULT_TIMEOUT;
    try {
        timeout = Long.parseLong(timeoutHdr.substring(7)) * 1000;
    } catch (NumberFormatException e) {
        // ignore, use default
        LOG.info("Using default timeout", e);
    }

    // check if new subscription or a renewal
    if (sidHdr != null) { // subscription renewal
        Map<UUID, SubscriptionInfo> m = subscriptions.get(key);
        if (m == null) {
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED,
                    "SID doesn't correspond to a known subscription.");
            return;
        }

        // parse SID
        String ss = sidHdr.substring(5).trim();
        UUID sid = new UUID(ss);

        SubscriptionInfo si = m.get(sid);
        if (si == null) {
            res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED,
                    "SID doesn't correspond to a known subscription.");
            return;
        }

        si.renew(timeout);
    } else { // new subscription

        // create subscription identifier
        UUID sid = new UUID();

        addSubscription(key, sid, new SubscriptionInfo(sid, timeout, callbackUrls));

        // Create response
        res.setStatus(HttpServletResponse.SC_OK);
        res.addHeader("SERVER", System.getProperty("os.name") + "/" + System.getProperty("os.version")
                + ", UPnP/1.1, rpi-rest/0.1");
        res.addHeader("SID", "uuid:" + sid.toString());
        res.addHeader("TIMEOUT", "Second-" + (timeout / 1000));
    }
}

From source file:net.dorokhov.pony.web.server.common.StreamingViewRenderer.java

@Override
protected void renderMergedOutputModel(Map objectMap, HttpServletRequest request, HttpServletResponse response)
        throws Exception {

    InputStream dataStream = (InputStream) objectMap.get(DownloadConstants.INPUT_STREAM);

    if (dataStream == null) {
        response.sendError(HttpServletResponse.SC_NOT_FOUND);
        return;//from ww  w.  ja  v a  2  s .  c  o m
    }
    long length = (Long) objectMap.get(DownloadConstants.CONTENT_LENGTH);
    String fileName = (String) objectMap.get(DownloadConstants.FILENAME);
    Date lastModifiedObj = (Date) objectMap.get(DownloadConstants.LAST_MODIFIED);

    if (StringUtils.isEmpty(fileName) || lastModifiedObj == null) {
        response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
        return;
    }
    long lastModified = lastModifiedObj.getTime();
    String contentType = (String) objectMap.get(DownloadConstants.CONTENT_TYPE);

    // Validate request headers for caching ---------------------------------------------------

    // If-None-Match header should contain "*" or ETag. If so, then return 304.
    String ifNoneMatch = request.getHeader("If-None-Match");
    if (ifNoneMatch != null && matches(ifNoneMatch, fileName)) {
        response.setHeader("ETag", fileName); // Required in 304.
        response.sendError(HttpServletResponse.SC_NOT_MODIFIED);
        return;
    }

    // If-Modified-Since header should be greater than LastModified. If so, then return 304.
    // This header is ignored if any If-None-Match header is specified.
    long ifModifiedSince = request.getDateHeader("If-Modified-Since");
    if (ifNoneMatch == null && ifModifiedSince != -1 && ifModifiedSince + 1000 > lastModified) {
        response.setHeader("ETag", fileName); // Required in 304.
        response.sendError(HttpServletResponse.SC_NOT_MODIFIED);
        return;
    }

    // Validate request headers for resume ----------------------------------------------------

    // If-Match header should contain "*" or ETag. If not, then return 412.
    String ifMatch = request.getHeader("If-Match");
    if (ifMatch != null && !matches(ifMatch, fileName)) {
        response.sendError(HttpServletResponse.SC_PRECONDITION_FAILED);
        return;
    }

    // If-Unmodified-Since header should be greater than LastModified. If not, then return 412.
    long ifUnmodifiedSince = request.getDateHeader("If-Unmodified-Since");
    if (ifUnmodifiedSince != -1 && ifUnmodifiedSince + 1000 <= lastModified) {
        response.sendError(HttpServletResponse.SC_PRECONDITION_FAILED);
        return;
    }

    // Validate and process range -------------------------------------------------------------

    // Prepare some variables. The full Range represents the complete file.
    Range full = new Range(0, length - 1, length);
    List<Range> ranges = new ArrayList<>();

    // Validate and process Range and If-Range headers.
    String range = request.getHeader("Range");
    if (range != null) {

        // Range header should match format "bytes=n-n,n-n,n-n...". If not, then return 416.
        if (!range.matches("^bytes=\\d*-\\d*(,\\d*-\\d*)*$")) {
            response.setHeader("Content-Range", "bytes */" + length); // Required in 416.
            response.sendError(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);
            return;
        }

        String ifRange = request.getHeader("If-Range");
        if (ifRange != null && !ifRange.equals(fileName)) {
            try {
                long ifRangeTime = request.getDateHeader("If-Range"); // Throws IAE if invalid.
                if (ifRangeTime != -1) {
                    ranges.add(full);
                }
            } catch (IllegalArgumentException ignore) {
                ranges.add(full);
            }
        }

        // If any valid If-Range header, then process each part of byte range.
        if (ranges.isEmpty()) {
            for (String part : range.substring(6).split(",")) {
                // Assuming a file with length of 100, the following examples returns bytes at:
                // 50-80 (50 to 80), 40- (40 to length=100), -20 (length-20=80 to length=100).
                long start = sublong(part, 0, part.indexOf("-"));
                long end = sublong(part, part.indexOf("-") + 1, part.length());

                if (start == -1) {
                    start = length - end;
                    end = length - 1;
                } else if (end == -1 || end > length - 1) {
                    end = length - 1;
                }

                // Check if Range is syntactically valid. If not, then return 416.
                if (start > end) {
                    response.setHeader("Content-Range", "bytes */" + length); // Required in 416.
                    response.sendError(HttpServletResponse.SC_REQUESTED_RANGE_NOT_SATISFIABLE);
                    return;
                }

                // Add range.
                ranges.add(new Range(start, end, length));
            }
        }
    }

    // Prepare and initialize response --------------------------------------------------------

    // Get content type by file name and set content disposition.
    String disposition = "inline";

    // If content type is unknown, then set the default value.
    // For all content types, see: http://www.w3schools.com/media/media_mimeref.asp
    // To add new content types, add new mime-mapping entry in web.xml.
    if (contentType == null) {
        contentType = "application/octet-stream";
    } else if (!contentType.startsWith("image")) {
        // Else, expect for images, determine content disposition. If content type is supported by
        // the browser, then set to inline, else attachment which will pop a 'save as' dialogue.
        String accept = request.getHeader("Accept");
        disposition = accept != null && accepts(accept, contentType) ? "inline" : "attachment";
    }

    // Initialize response.
    response.reset();
    response.setBufferSize(DEFAULT_BUFFER_SIZE);
    response.setHeader("Content-Disposition", disposition + ";filename=\"" + fileName + "\"");
    response.setHeader("Accept-Ranges", "bytes");
    response.setHeader("ETag", fileName);
    response.setDateHeader("Last-Modified", lastModified);
    response.setDateHeader("Expires", System.currentTimeMillis() + DEFAULT_EXPIRE_TIME);

    // Send requested file (part(s)) to client ------------------------------------------------

    // Prepare streams.
    InputStream input = null;
    OutputStream output = null;

    try {
        // Open streams.
        input = new BufferedInputStream(dataStream);
        output = response.getOutputStream();

        if (ranges.isEmpty() || ranges.get(0) == full) {

            // Return full file.
            response.setContentType(contentType);
            response.setHeader("Content-Range", "bytes " + full.start + "-" + full.end + "/" + full.total);
            response.setHeader("Content-Length", String.valueOf(full.length));
            copy(input, output, length, full.start, full.length);

        } else if (ranges.size() == 1) {

            // Return single part of file.
            Range r = ranges.get(0);
            response.setContentType(contentType);
            response.setHeader("Content-Range", "bytes " + r.start + "-" + r.end + "/" + r.total);
            response.setHeader("Content-Length", String.valueOf(r.length));
            response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT); // 206.

            // Copy single part range.
            copy(input, output, length, r.start, r.length);

        } else {

            // Return multiple parts of file.
            response.setContentType("multipart/byteranges; boundary=" + MULTIPART_BOUNDARY);
            response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT); // 206.

            // Cast back to ServletOutputStream to get the easy println methods.
            ServletOutputStream sos = (ServletOutputStream) output;

            // Copy multi part range.
            for (Range r : ranges) {
                // Add multipart boundary and header fields for every range.
                sos.println();
                sos.println("--" + MULTIPART_BOUNDARY);
                sos.println("Content-Type: " + contentType);
                sos.println("Content-Range: bytes " + r.start + "-" + r.end + "/" + r.total);

                // Copy single part range of multi part range.
                copy(input, output, length, r.start, r.length);
            }

            // End with multipart boundary.
            sos.println();
            sos.println("--" + MULTIPART_BOUNDARY + "--");
        }
    } finally {
        // Gently close streams.
        close(output);
        close(input);
        close(dataStream);
    }

}

From source file:com.almende.eve.transport.http.AgentServlet.java

/**
 * Handle hand shake.//ww  w . j ava  2 s  .c om
 * 
 * @param req
 *            the req
 * @param res
 *            the res
 * @return true, if successful
 * @throws IOException
 *             Signals that an I/O exception has occurred.
 */
private boolean handleHandShake(final HttpServletRequest req, final HttpServletResponse res)
        throws IOException {
    final String time = req.getHeader("X-Eve-requestToken");

    if (time == null) {
        return false;
    }

    final String token = TokenStore.get(time);
    if (token == null) {
        res.sendError(HttpServletResponse.SC_PRECONDITION_FAILED);
    } else {
        res.setHeader("X-Eve-replyToken", token);
        res.setStatus(HttpServletResponse.SC_OK);
        res.flushBuffer();
    }
    return true;
}