List of usage examples for javax.servlet WriteListener WriteListener
WriteListener
From source file:org.structr.pdf.servlet.PdfServlet.java
@Override protected void renderAsyncOutput(HttpServletRequest request, HttpServletResponse response, App app, RenderContext renderContext, DOMNode rootElement) throws IOException { final AsyncContext async = request.startAsync(); final ServletOutputStream out = async.getResponse().getOutputStream(); final AtomicBoolean finished = new AtomicBoolean(false); final DOMNode rootNode = rootElement; response.setContentType("application/pdf"); response.setHeader("Content-Disposition", "attachment;filename=\"FileName.pdf\""); threadPool.submit(new Runnable() { @Override// ww w.j av a 2s. com public void run() { try (final Tx tx = app.tx()) { // render rootNode.render(renderContext, 0); finished.set(true); tx.success(); } catch (Throwable t) { t.printStackTrace(); logger.warn("Error while rendering page {}: {}", rootNode.getName(), t.getMessage()); try { response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR); finished.set(true); } catch (IOException ex) { logger.warn("", ex); } } } }); // start output write listener out.setWriteListener(new WriteListener() { @Override public void onWritePossible() throws IOException { try { final Queue<String> queue = renderContext.getBuffer().getQueue(); String pageContent = ""; while (out.isReady()) { String buffer = null; synchronized (queue) { buffer = queue.poll(); } if (buffer != null) { pageContent += buffer; } else { if (finished.get()) { // TODO: implement parameters for wkhtmltopdf in settings Pdf pdf = new Pdf(); pdf.addPageFromString(pageContent); out.write(pdf.getPDF()); async.complete(); // prevent this block from being called again break; } Thread.sleep(1); } } } catch (EofException ee) { logger.warn( "Could not flush the response body content to the client, probably because the network connection was terminated."); } catch (IOException | InterruptedException t) { logger.warn("Unexpected exception", t); } } @Override public void onError(Throwable t) { if (t instanceof EofException) { logger.warn( "Could not flush the response body content to the client, probably because the network connection was terminated."); } else { logger.warn("Unexpected exception", t); } } }); }
From source file:org.structr.web.servlet.HtmlServlet.java
@Override protected void doGet(final HttpServletRequest request, final HttpServletResponse response) { final Authenticator auth = getConfig().getAuthenticator(); List<Page> pages = null; boolean requestUriContainsUuids = false; SecurityContext securityContext;/*w w w. ja v a 2 s .c o m*/ final App app; try { final String path = request.getPathInfo(); // check for registration (has its own tx because of write access if (checkRegistration(auth, request, response, path)) { return; } // check for registration (has its own tx because of write access if (checkResetPassword(auth, request, response, path)) { return; } // isolate request authentication in a transaction try (final Tx tx = StructrApp.getInstance().tx()) { securityContext = auth.initializeAndExamineRequest(request, response); tx.success(); } app = StructrApp.getInstance(securityContext); try (final Tx tx = app.tx()) { // Ensure access mode is frontend securityContext.setAccessMode(AccessMode.Frontend); request.setCharacterEncoding("UTF-8"); // Important: Set character encoding before calling response.getWriter() !!, see Servlet Spec 5.4 response.setCharacterEncoding("UTF-8"); boolean dontCache = false; logger.log(Level.FINE, "Path info {0}", path); // don't continue on redirects if (response.getStatus() == 302) { tx.success(); return; } final Principal user = securityContext.getUser(false); if (user != null) { // Don't cache if a user is logged in dontCache = true; } final RenderContext renderContext = RenderContext.getInstance(securityContext, request, response); renderContext.setResourceProvider(config.getResourceProvider()); final EditMode edit = renderContext.getEditMode(user); DOMNode rootElement = null; AbstractNode dataNode = null; final String[] uriParts = PathHelper.getParts(path); if ((uriParts == null) || (uriParts.length == 0)) { // find a visible page rootElement = findIndexPage(securityContext, pages, edit); logger.log(Level.FINE, "No path supplied, trying to find index page"); } else { if (rootElement == null) { rootElement = findPage(securityContext, pages, path, edit); } else { dontCache = true; } } if (rootElement == null) { // No page found // Look for a file final File file = findFile(securityContext, request, path); if (file != null) { streamFile(securityContext, file, request, response, edit); tx.success(); return; } // store remaining path parts in request final Matcher matcher = threadLocalUUIDMatcher.get(); for (int i = 0; i < uriParts.length; i++) { request.setAttribute(uriParts[i], i); matcher.reset(uriParts[i]); // set to "true" if part matches UUID pattern requestUriContainsUuids |= matcher.matches(); } if (!requestUriContainsUuids) { // Try to find a data node by name dataNode = findFirstNodeByName(securityContext, request, path); } else { dataNode = findNodeByUuid(securityContext, PathHelper.getName(path)); } //if (dataNode != null && !(dataNode instanceof Linkable)) { if (dataNode != null) { // Last path part matches a data node // Remove last path part and try again searching for a page // clear possible entry points request.removeAttribute(POSSIBLE_ENTRY_POINTS_KEY); rootElement = findPage(securityContext, pages, StringUtils.substringBeforeLast(path, PathHelper.PATH_SEP), edit); renderContext.setDetailsDataObject(dataNode); // Start rendering on data node if (rootElement == null && dataNode instanceof DOMNode) { rootElement = ((DOMNode) dataNode); } } } // look for pages with HTTP Basic Authentication (must be done as superuser) if (rootElement == null) { final HttpBasicAuthResult authResult = checkHttpBasicAuth(request, response, path); switch (authResult.authState()) { // Element with Basic Auth found and authentication succeeded case Authenticated: final Linkable result = authResult.getRootElement(); if (result instanceof Page) { rootElement = (DOMNode) result; securityContext = authResult.getSecurityContext(); renderContext.pushSecurityContext(securityContext); } else if (result instanceof File) { streamFile(authResult.getSecurityContext(), (File) result, request, response, EditMode.NONE); tx.success(); return; } break; // Page with Basic Auth found but not yet authenticated case MustAuthenticate: tx.success(); return; // no Basic Auth for given path, go on case NoBasicAuth: break; } } // Still nothing found, do error handling if (rootElement == null) { rootElement = notFound(response, securityContext); } if (rootElement == null) { tx.success(); return; } // check dont cache flag on page (if root element is a page) // but don't modify true to false dontCache |= rootElement.getProperty(Page.dontCache); if (EditMode.WIDGET.equals(edit) || dontCache) { setNoCacheHeaders(response); } if (!securityContext.isVisible(rootElement)) { rootElement = notFound(response, securityContext); if (rootElement == null) { tx.success(); return; } } else { if (!EditMode.WIDGET.equals(edit) && !dontCache && notModifiedSince(request, response, rootElement, dontCache)) { ServletOutputStream out = response.getOutputStream(); out.flush(); //response.flushBuffer(); out.close(); } else { // prepare response response.setCharacterEncoding("UTF-8"); String contentType = rootElement.getProperty(Page.contentType); if (contentType == null) { // Default contentType = "text/html;charset=UTF-8"; } if (contentType.equals("text/html")) { contentType = contentType.concat(";charset=UTF-8"); } response.setContentType(contentType); setCustomResponseHeaders(response); final boolean createsRawData = rootElement.getProperty(Page.pageCreatesRawData); // async or not? if (isAsync && !createsRawData) { final AsyncContext async = request.startAsync(); final ServletOutputStream out = async.getResponse().getOutputStream(); final AtomicBoolean finished = new AtomicBoolean(false); final DOMNode rootNode = rootElement; threadPool.submit(new Runnable() { @Override public void run() { try (final Tx tx = app.tx()) { //final long start = System.currentTimeMillis(); // render rootNode.render(renderContext, 0); finished.set(true); //final long end = System.currentTimeMillis(); //System.out.println("Done in " + (end-start) + " ms"); tx.success(); } catch (Throwable t) { t.printStackTrace(); final String errorMsg = t.getMessage(); try { //response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR); response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, errorMsg); finished.set(true); } catch (IOException ex) { ex.printStackTrace(); } } } }); // start output write listener out.setWriteListener(new WriteListener() { @Override public void onWritePossible() throws IOException { try { final Queue<String> queue = renderContext.getBuffer().getQueue(); while (out.isReady()) { String buffer = null; synchronized (queue) { buffer = queue.poll(); } if (buffer != null) { out.print(buffer); } else { if (finished.get()) { async.complete(); response.setStatus(HttpServletResponse.SC_OK); // prevent this block from being called again break; } Thread.sleep(1); } } } catch (Throwable t) { t.printStackTrace(); } } @Override public void onError(Throwable t) { t.printStackTrace(); } }); } else { final StringRenderBuffer buffer = new StringRenderBuffer(); renderContext.setBuffer(buffer); // render rootElement.render(renderContext, 0); try { response.getOutputStream().write(buffer.getBuffer().toString().getBytes("utf-8")); response.getOutputStream().flush(); response.getOutputStream().close(); } catch (IOException ioex) { ioex.printStackTrace(); } } } } tx.success(); } catch (FrameworkException fex) { fex.printStackTrace(); logger.log(Level.SEVERE, "Exception while processing request", fex); } } catch (IOException | FrameworkException t) { t.printStackTrace(); logger.log(Level.SEVERE, "Exception while processing request", t); UiAuthenticator.writeInternalServerError(response); } }