public void doGet()

in app/src/main/java/org/apache/roller/weblogger/ui/rendering/servlets/PreviewResourceServlet.java [69:178]
84 lines of code
16 McCabe index (conditional complexity)

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        Weblog weblog;

        WeblogPreviewResourceRequest resourceRequest;
        try {
            // parse the incoming request and extract the relevant data
            resourceRequest = new WeblogPreviewResourceRequest(request);

            weblog = resourceRequest.getWeblog();
            if (weblog == null) {
                throw new WebloggerException("unable to lookup weblog: "
                        + resourceRequest.getWeblogHandle());
            }

        } catch (Exception e) {
            // invalid resource request or weblog doesn't exist
            log.debug("error creating weblog resource request", e);
            response.sendError(HttpServletResponse.SC_NOT_FOUND);
            return;
        }

        log.debug("Resource requested [" + resourceRequest.getResourcePath()
                + "]");

        long resourceLastMod = 0;
        InputStream resourceStream = null;

        // first, see if we have a preview theme to operate from
        if (!StringUtils.isEmpty(resourceRequest.getThemeName())) {
            Theme theme = resourceRequest.getTheme();
            ThemeResource resource = theme.getResource(resourceRequest
                    .getResourcePath());
            if (resource != null) {
                resourceLastMod = resource.getLastModified();
                resourceStream = resource.getInputStream();
            }
        }

        // second, see if resource comes from weblog's configured shared theme
        if (resourceStream == null) {
            try {
                WeblogTheme weblogTheme = weblog.getTheme();
                if (weblogTheme != null) {
                    ThemeResource resource = weblogTheme
                            .getResource(resourceRequest.getResourcePath());
                    if (resource != null) {
                        resourceLastMod = resource.getLastModified();
                        resourceStream = resource.getInputStream();
                    }
                }
            } catch (Exception ex) {
                // hmmm, some kind of error getting theme. that's an error.
                response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
                if(resourceStream != null) {
                    resourceStream.close();
                }
                return;
            }
        }

        // if not from theme then see if resource is in weblog's upload dir
        if (resourceStream == null) {
            try {
                MediaFileManager mmgr = WebloggerFactory.getWeblogger()
                        .getMediaFileManager();
                MediaFile mf = mmgr.getMediaFileByOriginalPath(weblog,
                        resourceRequest.getResourcePath());
                resourceLastMod = mf.getLastModified();
                resourceStream = mf.getInputStream();

            } catch (Exception ex) {
                // still not found? then we don't have it, 404.
                log.debug("Unable to get resource", ex);
                response.sendError(HttpServletResponse.SC_NOT_FOUND);
                if(resourceStream != null) {
                    resourceStream.close();
                }
                return;
            }
        }

        // Respond with 304 Not Modified if it is not modified.
        if (ModDateHeaderUtil.respondIfNotModified(request, response,
                resourceLastMod, resourceRequest.getDeviceType())) {
            return;
        } else {
            // set last-modified date
            ModDateHeaderUtil.setLastModifiedHeader(response, resourceLastMod,
                    resourceRequest.getDeviceType());
        }

        // set the content type based on whatever is in our web.xml mime defs
        response.setContentType(this.context.getMimeType(resourceRequest
                .getResourcePath()));

        try {
            // ok, lets serve up the file
            resourceStream.transferTo(response.getOutputStream());

        } catch (IOException ex) {
            log.error("Error writing resource file", ex);
            if (!response.isCommitted()) {
                response.reset();
                response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            }
        }

    }