Example usage for javax.servlet.http HttpServletResponse SC_NOT_MODIFIED

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

Introduction

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

Prototype

int SC_NOT_MODIFIED

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Document

Status code (304) indicating that a conditional GET operation found that the resource was available and not modified.

Usage

From source file:com.venilnoronha.dzone.feed.web.LinksRSSController.java

@RequestMapping(value = "/rss/links", method = RequestMethod.GET)
public ModelAndView linksRssByLastModified(HttpEntity<byte[]> requestEntity, HttpServletRequest request,
        HttpServletResponse response) throws ParseException {
    HttpUtils.logUserIP("LinksRSS", request);
    String lastModified = requestEntity.getHeaders().getFirst("If-Modified-Since");
    if (lastModified == null) {
        lastModified = requestEntity.getHeaders().getFirst("If-None-Match");
    }//from  www  .  ja va2  s  . c  om
    PageRequest page = new PageRequest(0, feedSize, Direction.DESC, "linkDate");
    Page<Link> linkPage;
    if (lastModified != null) {
        Date lastModifiedDt = HTTP_FORMAT.parse(lastModified);
        linkPage = linksRepository.findByLinkDateBetween(lastModifiedDt, new Date(), page);
    } else {
        linkPage = linksRepository.findAll(page);
    }
    Iterator<Link> linksIter = linkPage.iterator();
    List<Link> links = new ArrayList<>();
    Date newLastModified = null;
    while (linksIter.hasNext()) {
        Link link = linksIter.next();
        Date linkDate = link.getLinkDate();
        if (newLastModified == null || newLastModified.before(linkDate)) {
            newLastModified = linkDate;
        }
        links.add(link);
    }
    if (links.isEmpty() && lastModified != null) {
        response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
        return null;
    } else {
        response.setHeader("ETag", HTTP_FORMAT.format(newLastModified));
        response.setHeader("Last-Modified", HTTP_FORMAT.format(newLastModified));
        ModelAndView mav = new ModelAndView();
        mav.setView(new LinksRSSView(links));
        return mav;
    }
}

From source file:org.apache.lucene.gdata.servlet.handler.DefaultGetHandler.java

/**
 * @see org.apache.lucene.gdata.servlet.handler.AbstractGdataRequestHandler#processRequest(javax.servlet.http.HttpServletRequest,
 *      javax.servlet.http.HttpServletResponse)
 *///from  w  w  w .  j ava 2s  .c o m
@Override
public void processRequest(HttpServletRequest request, HttpServletResponse response)
        throws IOException, ServletException {
    try {
        initializeRequestHandler(request, response, GDataRequestType.GET);
    } catch (GDataRequestException e) {
        sendError();
        return;
    }

    try {
        String modifiedSince = this.feedRequest.getModifiedSince();
        if (!checkIsModified(modifiedSince)) {
            this.feedResponse.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
            return;
        }
        if (LOG.isInfoEnabled())
            LOG.info("Requested output formate: " + this.feedRequest.getRequestedResponseFormat());
        this.feedResponse.setOutputFormat(this.feedRequest.getRequestedResponseFormat());
        if (this.feedRequest.isFeedRequested()) {
            BaseFeed feed = this.service.getFeed(this.feedRequest, this.feedResponse);

            this.feedResponse.sendResponse(feed, this.feedRequest.getConfigurator());
        } else {
            BaseEntry entry = this.service.getSingleEntry(this.feedRequest, this.feedResponse);
            this.feedResponse.sendResponse(entry, this.feedRequest.getConfigurator());
        }

    } catch (ServiceException e) {
        LOG.error("Could not process GetFeed request - " + e.getMessage(), e);
        setError(e.getErrorCode());
        sendError();
    } finally {
        closeService();
    }
}

From source file:com.lily.dap.web.util.WebUtils.java

/**
 *  If-None-Match Header,Etag./*from   w w w .j  a  v a2 s.  com*/
 * 
 * Etag,checkIfNoneMatchfalse, 304 not modify status.
 */
public static boolean checkIfNoneMatchEtag(HttpServletRequest request, HttpServletResponse response,
        String etag) {
    String headerValue = request.getHeader("If-None-Match");
    if (headerValue != null) {
        boolean conditionSatisfied = false;
        if (!headerValue.equals("*")) {
            StringTokenizer commaTokenizer = new StringTokenizer(headerValue, ",");

            while (!conditionSatisfied && commaTokenizer.hasMoreTokens()) {
                String currentToken = commaTokenizer.nextToken();
                if (currentToken.trim().equals(etag)) {
                    conditionSatisfied = true;
                }
            }
        } else {
            conditionSatisfied = true;
        }

        if (conditionSatisfied) {
            response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
            response.setHeader("ETag", etag);
            return false;
        }
    }
    return true;
}

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;/*ww  w.j  a va2  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.venilnoronha.dzone.feed.web.ArticlesRSSController.java

@RequestMapping(value = "/rss/articles", method = RequestMethod.GET)
public ModelAndView articlesRssByLastModified(HttpEntity<byte[]> requestEntity, HttpServletRequest request,
        HttpServletResponse response) throws ParseException {
    HttpUtils.logUserIP("ArticlesRSS", request);
    String lastModified = requestEntity.getHeaders().getFirst("If-Modified-Since");
    if (lastModified == null) {
        lastModified = requestEntity.getHeaders().getFirst("If-None-Match");
    }//w w w.  j a  va 2s  . c  o m
    PageRequest page = new PageRequest(0, feedSize, Direction.DESC, "articleDate");
    Page<Article> articlePage;
    if (lastModified != null) {
        Date lastModifiedDt = HTTP_FORMAT.parse(lastModified);
        articlePage = articlesRepository.findByArticleDateBetween(lastModifiedDt, new Date(), page);
    } else {
        articlePage = articlesRepository.findAll(page);
    }
    Iterator<Article> articlesIter = articlePage.iterator();
    List<Article> articles = new ArrayList<>();
    Date newLastModified = null;
    while (articlesIter.hasNext()) {
        Article article = articlesIter.next();
        Date articleDate = article.getArticleDate();
        if (newLastModified == null || newLastModified.before(articleDate)) {
            newLastModified = articleDate;
        }
        articles.add(article);
    }
    if (articles.isEmpty() && lastModified != null) {
        response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
        return null;
    } else {
        response.setHeader("ETag", HTTP_FORMAT.format(newLastModified));
        response.setHeader("Last-Modified", HTTP_FORMAT.format(newLastModified));
        ModelAndView mav = new ModelAndView();
        mav.setView(new ArticlesRSSView(articles));
        return mav;
    }
}

From source file:annis.gui.servlets.ResourceServlet.java

@Override
@SuppressWarnings("unchecked")
public void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    OutputStream outStream = response.getOutputStream();

    String completePath = request.getPathInfo();

    if (completePath == null) {
        response.sendError(404, "must provide a valid and existing path with a vistype");
        return;/*from   w w w.  j  a v  a  2s . c om*/
    }

    // remove trailing /
    completePath = completePath.substring(1);

    String[] pathComponents = completePath.split("/");

    String vistype = pathComponents[0];

    if (pathComponents.length < 2) {
        response.sendError(404, "must provide a valid and existing path");
        return;
    }

    String path = StringUtils.join(Arrays.copyOfRange(pathComponents, 1, pathComponents.length), "/");

    // get the visualizer for this vistype
    ResourcePlugin vis = resourceRegistry.get(vistype);
    if (vis == null) {
        response.sendError(500, "There is no resource with the short name " + vistype);
    } else if (path.endsWith(".class")) {
        response.sendError(403, "illegal class path access");
    } else {
        URL resource = vis.getClass().getResource(path);
        if (resource == null) {
            response.sendError(404, path + " not found");
        } else {
            // check if it is new
            URLConnection resourceConnection = resource.openConnection();
            long resourceLastModified = resourceConnection.getLastModified();
            long requestLastModified = request.getDateHeader("If-Modified-Since");
            if (requestLastModified != -1 && resourceLastModified <= requestLastModified) {
                response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
            } else {
                response.addDateHeader("Last-Modified", resourceLastModified);
                if ("localhost".equals(request.getServerName())) {
                    // does always expire right now
                    response.addDateHeader("Expires", new Date().getTime());
                } else {
                    // expires in one minute per default
                    response.addDateHeader("Expires", new Date().getTime() + 60000);
                }
                // not in cache, stream out
                String mimeType = getServletContext().getMimeType(path);
                response.setContentType(mimeType);
                if (mimeType.startsWith("text/")) {
                    response.setCharacterEncoding("UTF-8");
                }
                OutputStream bufferedOut = new BufferedOutputStream(outStream);
                InputStream resourceInStream = new BufferedInputStream(resource.openStream());

                try {
                    int v = -1;
                    while ((v = resourceInStream.read()) != -1) {
                        bufferedOut.write(v);
                    }
                } finally {
                    resourceInStream.close();
                    bufferedOut.flush();
                    outStream.flush();
                }
            }
        }
    }

}

From source file:com.emaxcore.emaxdata.common.web.Servlets.java

/**
 * ?? If-None-Match Header, Etag?.//from w w w .ja v a2s. c  om
 *
 * Etag, checkIfNoneMatchfalse, 304 not modify status.
 *
 * @param etag ETag.
 */
public static boolean checkIfNoneMatchEtag(HttpServletRequest request, HttpServletResponse response,
        String etag) {
    String headerValue = request.getHeader(HttpHeaders.IF_NONE_MATCH);
    if (headerValue != null) {
        boolean conditionSatisfied = false;
        if (!"*".equals(headerValue)) {
            StringTokenizer commaTokenizer = new StringTokenizer(headerValue, ",");
            while (!conditionSatisfied && commaTokenizer.hasMoreTokens()) {
                String currentToken = commaTokenizer.nextToken();
                if (currentToken.trim().equals(etag)) {
                    conditionSatisfied = true;
                }
            }
        } else {
            conditionSatisfied = true;
        }

        if (conditionSatisfied) {
            response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
            response.setHeader(HttpHeaders.ETAG, etag);
            return false;
        }
    }
    return true;
}

From source file:com.mirantis.cachemod.filter.CacheFilter.java

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
        throws ServletException, IOException {

    if (request.getAttribute(conf.getAlreadyFilteredKey()) != null || !isCacheable(request)) {

        /*/*from  www.  ja  v  a  2  s .c  o  m*/
         *  This request is not Cacheable
         */

        chain.doFilter(request, response);
    } else {
        request.setAttribute(conf.getAlreadyFilteredKey(), Boolean.TRUE);

        HttpServletRequest httpRequest = (HttpServletRequest) request;
        boolean fragmentRequest = isFragment(httpRequest);

        String key = conf.getCacheKeyProvider().createKey(httpRequest);

        CacheEntry cacheEntry = conf.getCacheProvider().getEntry(key);
        if (cacheEntry != null) {

            if (!fragmentRequest) {

                /*
                 * -1 of no in header
                 */
                long clientLastModified = httpRequest.getDateHeader("If-Modified-Since");

                /*
                 * Reply with SC_NOT_MODIFIED for client that has newest page 
                 */
                if ((clientLastModified != -1) && (clientLastModified >= cacheEntry.getLastModified())) {
                    ((HttpServletResponse) response).setStatus(HttpServletResponse.SC_NOT_MODIFIED);
                    return;
                }
            }

            writeCacheToResponse(cacheEntry, response, fragmentRequest);

        } else {
            cacheEntry = conf.getCacheProvider().instantiateEntry();

            CacheHttpServletResponse cacheResponse = new CacheHttpServletResponse(
                    (HttpServletResponse) response, cacheEntry, conf, fragmentRequest);
            chain.doFilter(request, cacheResponse);

            if (cacheResponse.getStatus() == HttpServletResponse.SC_OK) {
                cacheResponse.commit();
                if (conf.getUserDataProvider() != null) {
                    cacheEntry.setUserData(conf.getUserDataProvider().createUserData(httpRequest));
                }
                conf.getCacheProvider().putEntry(key, cacheEntry);
            }
        }
    }

}

From source file:com.swingtech.apps.filemgmt.controller.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  .  j  av  a2  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 && HttpUtils.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 && !HttpUtils.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<Range>();

    // 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 = StringUtils.sublong(part, 0, part.indexOf("-"));
                long end = StringUtils.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 && HttpUtils.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.
            Range r = full;
            response.setContentType(contentType);
            response.setHeader("Content-Range", "bytes " + r.start + "-" + r.end + "/" + r.total);
            response.setHeader("Content-Length", String.valueOf(r.length));
            copy(input, output, length, r.start, r.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.thoughtworks.go.domain.ChecksumFileHandlerTest.java

@Test
public void shouldHandleResultIfHttpCodeSaysFileNotModified() {
    StubGoPublisher goPublisher = new StubGoPublisher();
    assertThat(checksumFileHandler.handleResult(HttpServletResponse.SC_NOT_MODIFIED, goPublisher), is(true));
}