Java 类com.vaadin.server.RequestHandler 实例源码

@Override
protected List<RequestHandler> createRequestHandlers()
    throws ServiceException {
    List<RequestHandler> handlers = super.createRequestHandlers();
    handlers.add(0, new ServletBootstrapHandler());
    handlers.add(new ServletUIInitHandler());
    if (isAtmosphereAvailable()) {
        handlers.add((RequestHandler) (session, request, response) -> {
            if (!ServletPortletHelper.isPushRequest(request)) {
                return false;
            }
            if (request instanceof VertxVaadinRequest) {
                ((VertxVaadinRequest) request).getRoutingContext().next();
            }
            return true;
        });
    }
    return handlers;
}

/**
 * initalize a unique RequestHandler
 */
private void initRequestHandler() {
    if (this.requestHandlerUri == null) {
        this.requestHandlerUri = UUID.randomUUID()
                .toString();
        VaadinSession.getCurrent()
                .addRequestHandler(new RequestHandler() {

                    @Override
                    public boolean handleRequest(final VaadinSession session, final VaadinRequest request, final VaadinResponse response)
                            throws IOException {
                        if (String.format("/%s", Jcrop.this.requestHandlerUri)
                                .equals(request.getPathInfo())) {
                            Jcrop.this.resource.getStream()
                                    .writeResponse(request, response);
                            return true;
                        } else {
                            return false;
                        }
                    }
                });
    }
}

@Override
protected void servletInitialized() throws ServletException {
    super.servletInitialized();

          HeaderTagHandler.init(getService());

    getService().addSessionInitListener(new SessionInitListener() {

        @Override
        public void sessionInit(SessionInitEvent event) throws ServiceException {
            event.getSession().addRequestHandler(new RequestHandler() {

                @Override
                public boolean handleRequest(VaadinSession session, VaadinRequest request,
                        VaadinResponse response) throws IOException {

                    String pathInfo = request.getPathInfo();
                    InputStream in = null;

                    if (pathInfo.endsWith("sw.js")) {
                        response.setContentType("application/javascript");
                        in = getClass().getResourceAsStream("/sw.js");
                    }

                    if (in != null) {
                        OutputStream out = response.getOutputStream();
                        IOUtils.copy(in, out);
                        in.close();
                        out.close();

                        return true;
                    } else {

                        return false;
                    }
                }
            });
        }
    });
}

/**
  * Creates the parameter handler that will be invoked when the user returns
  * from the OAuth service.
  * 
  * @return the parameter handler
  */
 protected RequestHandler createRequestHandler() {
     return new RequestHandler() {
public boolean handleRequest(VaadinSession session,
        VaadinRequest request, VaadinResponse response)
        throws IOException {
             if (request.getParameterMap().containsKey(getVerifierName())) {
                 String v = request.getParameter(getVerifierName());
                 Verifier verifier = new Verifier(v);
                 accessToken = service
                         .getAccessToken(requestToken, verifier);

                 User user = getUser();

                 VaadinSession.getCurrent().removeRequestHandler(handler);
                 handler = null;

                 //String url = getAuthUrl();
                 //callbackPage.open(url, "Authentificate", 400, 300, BorderStyle.DEFAULT);

                 authListener.userAuthenticated(user);

             } else if (getFailureParameters() != null) {
                 for (String key : getFailureParameters()) {
                     if (request.getParameterMap().containsKey(key)) {
                         authListener.failed(request.getParameter(key));
                         break;
                     }
                 }
             }
    return true;
         }
     };
 }