@Before public void setup() { mockServlet = new VaadinServlet() { @Override public String getServletName() { return "mockServlet"; }; }; mockService = new VaadinServletService(mockServlet, EasyMock.createMock(DeploymentConfiguration.class)); mockHttpSession = EasyMock.createMock(HttpSession.class); mockWrappedSession = new WrappedHttpSession(mockHttpSession) { final ReentrantLock lock = new ReentrantLock(); @Override public Object getAttribute(String name) { if ("mockServlet.lock".equals(name)) { return lock; } return super.getAttribute(name); } }; session = new VaadinSession(mockService); session.storeInSession(mockService, mockWrappedSession); ui = new UI() { Page page = new Page(this) { @Override public void init(VaadinRequest request) {} }; @Override protected void init(VaadinRequest request) {} @Override public Page getPage() { return page; } }; vaadinRequest = new VaadinServletRequest(EasyMock.createMock(HttpServletRequest.class), mockService) { @Override public String getParameter(String name) { if ("theme".equals(name)) { return null; } return super.getParameter(name); } }; ui.doInit(vaadinRequest, session.getNextUIid()); ui.setSession(session); session.addUI(ui); }