Refactored how all requests are handled by VaadinServlet and VaadinPortlet (#11192)

* Handling is now based on a list of RequestHandlers in VaadinService
* Request handling logic has been moved to VaadinService
* Users can customize the list by adding own (service level) request handlers
* For users specific request handlers you can still use the request handlers in VaadinSession
* Deprecated RequestType - all handlers are given the opportunity to handle a request until one of them chooses to handle it. RequestType makes no sense as it does not tell which handler will handle the request.
* Removed serveStaticResource which has never been used

Change-Id: Ia7d088535e46430ca8adf631d3f1dd944b9d51e2

server/src/com/vaadin/server/BootstrapHandler.java

@@ -115,6 +115,12 @@ public abstract class BootstrapHandler extends SynchronizedRequestHandler {
     @Override
     public boolean synchronizedHandleRequest(VaadinSession session,
             VaadinRequest request, VaadinResponse response) throws IOException {
+        String pathInfo = request.getPathInfo();
+        if (pathInfo.startsWith("/" + ApplicationConstants.APP_PATH + "/")) {
+            // We do not want to handle /APP requests here, instead let it fall
+            // through and produce a 404
+            return false;
+        }
 
         try {
             List<UIProvider> uiProviders = session.getUIProviders();

server/src/com/vaadin/server/ConnectorResourceHandler.java

@@ -48,60 +48,50 @@ public class ConnectorResourceHandler implements RequestHandler {
             return false;
         }
         Matcher matcher = CONNECTOR_RESOURCE_PATTERN.matcher(requestPath);
-        if (matcher.matches()) {
-            String uiId = matcher.group(1);
-            String cid = matcher.group(2);
-            String key = matcher.group(3);
-
-            session.lock();
-            UI ui;
-            ClientConnector connector;
-            try {
-                ui = session.getUIById(Integer.parseInt(uiId));
-                if (ui == null) {
-                    return error(request, response,
-                            "Ignoring connector request for no-existent root "
-                                    + uiId);
-                }
-
-                connector = ui.getConnectorTracker().getConnector(cid);
-                if (connector == null) {
-                    return error(request, response,
-                            "Ignoring connector request for no-existent connector "
-                                    + cid + " in root " + uiId);
-                }
+        if (!matcher.matches()) {
+            return false;
+        }
+        String uiId = matcher.group(1);
+        String cid = matcher.group(2);
+        String key = matcher.group(3);
 
-            } finally {
-                session.unlock();
+        session.lock();
+        UI ui;
+        ClientConnector connector;
+        try {
+            ui = session.getUIById(Integer.parseInt(uiId));
+            if (ui == null) {
+                return error(request, response,
+                        "Ignoring connector request for no-existent root "
+                                + uiId);
             }
 
-            Map<Class<?>, CurrentInstance> oldThreadLocals = CurrentInstance
-                    .setThreadLocals(ui);
-            try {
-                if (!connector.handleConnectorRequest(request, response, key)) {
-                    return error(request, response,
-                            connector.getClass().getSimpleName() + " ("
-                                    + connector.getConnectorId()
-                                    + ") did not handle connector request for "
-                                    + key);
-                }
-            } finally {
-                CurrentInstance.restoreThreadLocals(oldThreadLocals);
+            connector = ui.getConnectorTracker().getConnector(cid);
+            if (connector == null) {
+                return error(request, response,
+                        "Ignoring connector request for no-existent connector "
+                                + cid + " in root " + uiId);
             }
 
-            return true;
-        } else if (requestPath.matches('/' + ApplicationConstants.APP_PATH
-                + "(/.*)?")) {
-            /*
-             * This should be the last request handler before we get to
-             * bootstrap logic. Prevent /APP requests from reaching bootstrap
-             * handlers to help protect the /APP name space for framework usage.
-             */
-            return error(request, response,
-                    "Returning 404 for /APP request not yet handled.");
-        } else {
-            return false;
+        } finally {
+            session.unlock();
         }
+
+        Map<Class<?>, CurrentInstance> oldThreadLocals = CurrentInstance
+                .setThreadLocals(ui);
+        try {
+            if (!connector.handleConnectorRequest(request, response, key)) {
+                return error(request, response, connector.getClass()
+                        .getSimpleName()
+                        + " ("
+                        + connector.getConnectorId()
+                        + ") did not handle connector request for " + key);
+            }
+        } finally {
+            CurrentInstance.restoreThreadLocals(oldThreadLocals);
+        }
+
+        return true;
     }
 
     private static boolean error(VaadinRequest request,

server/src/com/vaadin/server/GAEVaadinServlet.java

@@ -184,16 +184,14 @@ public class GAEVaadinServlet extends VaadinServlet {
             return;
         }
 
-        RequestType requestType = getRequestType(request);
-
-        if (requestType == RequestType.STATIC_FILE) {
+        if (isStaticResourceRequest(request)) {
             // no locking needed, let superclass handle
             super.service(request, response);
             cleanSession(request);
             return;
         }
 
-        if (requestType == RequestType.APP) {
+        if (ServletPortletHelper.isAppRequest(request)) {
             // no locking needed, let superclass handle
             getApplicationContext(request,
                     MemcacheServiceFactory.getMemcacheService());
@@ -205,7 +203,11 @@ public class GAEVaadinServlet extends VaadinServlet {
         final HttpSession session = request.getSession(getService()
                 .requestCanCreateSession(request));
         if (session == null) {
-            handleServiceSessionExpired(request, response);
+            try {
+                getService().handleSessionExpired(request, response);
+            } catch (ServiceException e) {
+                throw new ServletException(e);
+            }
             cleanSession(request);
             return;
         }
@@ -218,19 +220,21 @@ public class GAEVaadinServlet extends VaadinServlet {
             // try to get lock
             long started = new Date().getTime();
             // non-UIDL requests will try indefinitely
-            while (requestType != RequestType.UIDL
-                    || new Date().getTime() - started < MAX_UIDL_WAIT_MILLISECONDS) {
-                locked = memcache.put(mutex, 1, Expiration.byDeltaSeconds(40),
-                        MemcacheService.SetPolicy.ADD_ONLY_IF_NOT_PRESENT);
-                if (locked) {
-                    break;
-                }
-                try {
-                    Thread.sleep(RETRY_AFTER_MILLISECONDS);
-                } catch (InterruptedException e) {
-                    getLogger().finer(
-                            "Thread.sleep() interrupted while waiting for lock. Trying again. "
-                                    + e);
+            if (!ServletPortletHelper.isUIDLRequest(request)) {
+                while (new Date().getTime() - started < MAX_UIDL_WAIT_MILLISECONDS) {
+                    locked = memcache.put(mutex, 1,
+                            Expiration.byDeltaSeconds(40),
+                            MemcacheService.SetPolicy.ADD_ONLY_IF_NOT_PRESENT);
+                    if (locked) {
+                        break;
+                    }
+                    try {
+                        Thread.sleep(RETRY_AFTER_MILLISECONDS);
+                    } catch (InterruptedException e) {
+                        getLogger().finer(
+                                "Thread.sleep() interrupted while waiting for lock. Trying again. "
+                                        + e);
+                    }
                 }
             }
 

server/src/com/vaadin/server/LegacyCommunicationManager.java

@@ -65,10 +65,6 @@ public class LegacyCommunicationManager implements Serializable {
     // TODO PUSH move
     public static final String WRITE_SECURITY_TOKEN_FLAG = "writeSecurityToken";
 
-    private static final RequestHandler UNSUPPORTED_BROWSER_HANDLER = new UnsupportedBrowserHandler();
-
-    private static final RequestHandler CONNECTOR_RESOURCE_HANDLER = new ConnectorResourceHandler();
-
     /**
      * TODO Document me!
      * 
@@ -112,10 +108,6 @@ public class LegacyCommunicationManager implements Serializable {
      */
     public LegacyCommunicationManager(VaadinSession session) {
         this.session = session;
-        session.addRequestHandler(session.getService().createBootstrapHandler(
-                session));
-        session.addRequestHandler(UNSUPPORTED_BROWSER_HANDLER);
-        session.addRequestHandler(CONNECTOR_RESOURCE_HANDLER);
         requireLocale(session.getLocale().toString());
     }
 

server/src/com/vaadin/server/VaadinPortlet.java

@@ -17,17 +17,14 @@ package com.vaadin.server;
 
 import java.io.BufferedWriter;
 import java.io.IOException;
-import java.io.InputStream;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.io.Serializable;
 import java.lang.reflect.Method;
-import java.net.MalformedURLException;
 import java.util.Enumeration;
 import java.util.Map;
 import java.util.Properties;
-import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import javax.portlet.ActionRequest;
@@ -46,18 +43,11 @@ import javax.portlet.ResourceRequest;
 import javax.portlet.ResourceResponse;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletRequestWrapper;
-import javax.servlet.http.HttpServletResponse;
 
 import com.liferay.portal.kernel.util.PortalClassInvoker;
 import com.liferay.portal.kernel.util.PropsUtil;
-import com.vaadin.server.LegacyCommunicationManager.Callback;
-import com.vaadin.server.communication.FileUploadHandler;
-import com.vaadin.server.communication.HeartbeatHandler;
-import com.vaadin.server.communication.PortletListenerNotifier;
-import com.vaadin.server.communication.PublishedFileHandler;
-import com.vaadin.server.communication.SessionRequestHandler;
-import com.vaadin.server.communication.UIInitHandler;
-import com.vaadin.server.communication.UidlRequestHandler;
+import com.vaadin.server.communication.PortletDummyRequestHandler;
+import com.vaadin.server.communication.PortletUIInitHandler;
 import com.vaadin.util.CurrentInstance;
 
 /**
@@ -207,24 +197,6 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
 
     }
 
-    public static class AbstractApplicationPortletWrapper implements Callback {
-
-        private final VaadinPortlet portlet;
-
-        public AbstractApplicationPortletWrapper(VaadinPortlet portlet) {
-            this.portlet = portlet;
-        }
-
-        @Override
-        public void criticalNotification(VaadinRequest request,
-                VaadinResponse response, String cap, String msg,
-                String details, String outOfSyncURL) throws IOException {
-            portlet.criticalNotification((VaadinPortletRequest) request,
-                    (VaadinPortletResponse) response, cap, msg, details,
-                    outOfSyncURL);
-        }
-    }
-
     /**
      * This portlet parameter is used to add styles to the main element. E.g
      * "height:500px" generates a style="height:500px" to the main element.
@@ -287,6 +259,7 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
         vaadinService.setCurrentInstances(null, null);
 
         portletInitialized();
+
         CurrentInstance.clearAll();
     }
 
@@ -307,8 +280,10 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
     /**
      * @author Vaadin Ltd
      * 
-     * @deprecated As of 7.0. Will likely change or be removed in a future
-     *             version
+     * @deprecated As of 7.0. This is no longer used and only provided for
+     *             backwards compatibility. Each {@link RequestHandler} can
+     *             individually decide whether it wants to handle a request or
+     *             not.
      */
     @Deprecated
     protected enum RequestType {
@@ -319,8 +294,10 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
      * @param vaadinRequest
      * @return
      * 
-     * @deprecated As of 7.0. Will likely change or be removed in a future
-     *             version
+     * @deprecated As of 7.0. This is no longer used and only provided for
+     *             backwards compatibility. Each {@link RequestHandler} can
+     *             individually decide whether it wants to handle a request or
+     *             not.
      */
     @Deprecated
     protected RequestType getRequestType(VaadinPortletRequest vaadinRequest) {
@@ -331,7 +308,7 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
             ResourceRequest resourceRequest = (ResourceRequest) request;
             if (ServletPortletHelper.isUIDLRequest(vaadinRequest)) {
                 return RequestType.UIDL;
-            } else if (isBrowserDetailsRequest(resourceRequest)) {
+            } else if (PortletUIInitHandler.isUIInitRequest(vaadinRequest)) {
                 return RequestType.BROWSER_DETAILS;
             } else if (ServletPortletHelper.isFileUploadRequest(vaadinRequest)) {
                 return RequestType.FILE_UPLOAD;
@@ -342,7 +319,7 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
                 return RequestType.APP;
             } else if (ServletPortletHelper.isHeartbeatRequest(vaadinRequest)) {
                 return RequestType.HEARTBEAT;
-            } else if (isDummyRequest(resourceRequest)) {
+            } else if (PortletDummyRequestHandler.isDummyRequest(vaadinRequest)) {
                 return RequestType.DUMMY;
             } else {
                 return RequestType.STATIC_FILE;
@@ -355,16 +332,6 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
         return RequestType.UNKNOWN;
     }
 
-    private boolean isBrowserDetailsRequest(ResourceRequest request) {
-        return request.getResourceID() != null
-                && request.getResourceID().equals("v-browserDetails");
-    }
-
-    private boolean isDummyRequest(ResourceRequest request) {
-        return request.getResourceID() != null
-                && request.getResourceID().equals("DUMMY");
-    }
-
     /**
      * @param request
      * @param response
@@ -380,93 +347,11 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
 
         CurrentInstance.clearAll();
         setCurrent(this);
-        handleRequest(createVaadinRequest(request),
-                createVaadinResponse(response));
-    }
-
-    protected void handleRequest(VaadinPortletRequest request,
-            VaadinPortletResponse response) throws PortletException,
-            IOException {
-        getService().requestStart(request, response);
-
-        VaadinPortletSession vaadinSession = null;
         try {
-            AbstractApplicationPortletWrapper portletWrapper = new AbstractApplicationPortletWrapper(
-                    this);
-
-            RequestType requestType = getRequestType(request);
-
-            if (requestType == RequestType.UNKNOWN) {
-                handleUnknownRequest(request, response);
-            } else if (requestType == RequestType.DUMMY) {
-                /*
-                 * This dummy page is used by action responses to redirect to,
-                 * in order to prevent the boot strap code from being rendered
-                 * into strange places such as iframes.
-                 */
-                ((ResourceResponse) response).setContentType("text/html");
-                final OutputStream out = ((ResourceResponse) response)
-                        .getPortletOutputStream();
-                final PrintWriter outWriter = new PrintWriter(
-                        new BufferedWriter(new OutputStreamWriter(out, "UTF-8")));
-                outWriter.print("<html><body>dummy page</body></html>");
-                outWriter.close();
-            } else if (requestType == RequestType.STATIC_FILE) {
-                serveStaticResources((ResourceRequest) request,
-                        (ResourceResponse) response);
-            } else {
-                try {
-                    vaadinSession = (VaadinPortletSession) getService()
-                            .findVaadinSession(request);
-                    if (vaadinSession == null) {
-                        return;
-                    }
-
-                    if (requestType == RequestType.PUBLISHED_FILE) {
-                        new PublishedFileHandler().handleRequest(vaadinSession,
-                                request, response);
-                        return;
-                    } else if (requestType == RequestType.HEARTBEAT) {
-                        new HeartbeatHandler().handleRequest(vaadinSession,
-                                request, response);
-                        return;
-                    }
-
-                    // Notify listeners
-                    new PortletListenerNotifier().handleRequest(vaadinSession,
-                            request, response);
-
-                    /* Handle the request */
-                    if (requestType == RequestType.FILE_UPLOAD) {
-                        new FileUploadHandler().handleRequest(vaadinSession,
-                                request, response);
-                        return;
-                    } else if (requestType == RequestType.BROWSER_DETAILS) {
-                        new UIInitHandler().handleRequest(vaadinSession,
-                                request, response);
-                        return;
-                    } else if (requestType == RequestType.UIDL) {
-                        // Handles AJAX UIDL requests
-                        new UidlRequestHandler(portletWrapper).handleRequest(
-                                vaadinSession, request, response);
-
-                        return;
-                    } else {
-                        handleOtherRequest(request, response, requestType,
-                                vaadinSession,
-                                vaadinSession.getCommunicationManager());
-                    }
-                } catch (final SessionExpiredException e) {
-                    // TODO Figure out a better way to deal with
-                    // SessionExpiredExceptions
-                    getLogger().finest("A user session has expired");
-                } catch (final Throwable e) {
-                    handleServiceException(request, response, vaadinSession, e);
-
-                }
-            }
-        } finally {
-            getService().requestEnd(request, response, vaadinSession);
+            getService().handleRequest(createVaadinRequest(request),
+                    createVaadinResponse(response));
+        } catch (ServiceException e) {
+            throw new PortletException(e);
         }
     }
 
@@ -498,80 +383,12 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
         return vaadinService;
     }
 
-    private void handleUnknownRequest(VaadinPortletRequest request,
-            VaadinPortletResponse response) {
-        getLogger().warning("Unknown request type");
-    }
-
-    /**
-     * Handle a portlet request that is not for static files, UIDL or upload.
-     * Also render requests are handled here.
-     * 
-     * This method is called after starting the application and calling portlet
-     * and transaction listeners.
-     * 
-     * @param request
-     * @param response
-     * @param requestType
-     * @param vaadinSession
-     * @param vaadinSession
-     * @param communicationManager
-     * @throws PortletException
-     * @throws IOException
-     * @throws MalformedURLException
-     */
-    private void handleOtherRequest(VaadinPortletRequest request,
-            VaadinResponse response, RequestType requestType,
-            VaadinSession vaadinSession,
-            LegacyCommunicationManager communicationManager)
-            throws PortletException, IOException, MalformedURLException {
-        if (requestType == RequestType.APP || requestType == RequestType.RENDER) {
-            if (!new SessionRequestHandler().handleRequest(vaadinSession,
-                    request, response)) {
-                response.sendError(HttpServletResponse.SC_NOT_FOUND,
-                        "Not found");
-            }
-        } else if (requestType == RequestType.EVENT) {
-            // nothing to do, listeners do all the work
-        } else if (requestType == RequestType.ACTION) {
-            // nothing to do, listeners do all the work
-        } else {
-            throw new IllegalStateException(
-                    "handleRequest() without anything to do - should never happen!");
-        }
-    }
-
     @Override
     public void processEvent(EventRequest request, EventResponse response)
             throws PortletException, IOException {
         handleRequest(request, response);
     }
 
-    private void serveStaticResources(ResourceRequest request,
-            ResourceResponse response) throws IOException, PortletException {
-        final String resourceID = request.getResourceID();
-        final PortletContext pc = getPortletContext();
-
-        InputStream is = pc.getResourceAsStream(resourceID);
-        if (is != null) {
-            final String mimetype = pc.getMimeType(resourceID);
-            if (mimetype != null) {
-                response.setContentType(mimetype);
-            }
-            final OutputStream os = response.getPortletOutputStream();
-            final byte buffer[] = new byte[DEFAULT_BUFFER_SIZE];
-            int bytes;
-            while ((bytes = is.read(buffer)) >= 0) {
-                os.write(buffer, 0, bytes);
-            }
-        } else {
-            getLogger().log(Level.INFO,
-                    "Requested resource [{0}] could not be found", resourceID);
-            response.setProperty(ResourceResponse.HTTP_STATUS_CODE,
-                    Integer.toString(HttpServletResponse.SC_NOT_FOUND));
-        }
-    }
-
     @Override
     public void processAction(ActionRequest request, ActionResponse response)
             throws PortletException, IOException {
@@ -606,44 +423,6 @@ public class VaadinPortlet extends GenericPortlet implements Constants,
         handleRequest(request, response);
     }
 
-    private void handleServiceException(VaadinPortletRequest request,
-            VaadinPortletResponse response, VaadinSession vaadinSession,
-            Throwable e) throws IOException, PortletException {
-        // TODO Check that this error handler is working when running inside a
-        // portlet
-        if (vaadinSession != null) {
-            vaadinSession.lock();
-        }
-        try {
-            // if this was an UIDL request, response UIDL back to client
-            ErrorHandler errorHandler = ErrorEvent
-                    .findErrorHandler(vaadinSession);
-            if (getRequestType(request) == RequestType.UIDL) {
-                SystemMessages ci = getService().getSystemMessages(
-                        ServletPortletHelper.findLocale(null, vaadinSession,
-                                request), request);
-                criticalNotification(request, response,
-                        ci.getInternalErrorCaption(),
-                        ci.getInternalErrorMessage(), null,
-                        ci.getInternalErrorURL());
-                if (errorHandler != null) {
-                    errorHandler.error(new ErrorEvent(e));
-                }
-            } else {
-                if (errorHandler != null) {
-                    errorHandler.error(new ErrorEvent(e));
-                } else {
-                    // Re-throw other exceptions
-                    throw new PortletException(e);
-                }
-            }
-        } finally {
-            if (vaadinSession != null) {
-                vaadinSession.unlock();
-            }
-        }
-    }
-
     /**
      * Send notification to client's application. Used to notify client of
      * critical errors and session expiration due to long inactivity. Server has

server/src/com/vaadin/server/VaadinPortletService.java

@@ -17,17 +17,23 @@
 package com.vaadin.server;
 
 import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
+import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import javax.portlet.EventRequest;
 import javax.portlet.PortletContext;
 import javax.portlet.PortletRequest;
-
+import javax.portlet.RenderRequest;
 
 import com.vaadin.server.VaadinPortlet.RequestType;
 import com.vaadin.server.communication.PortletBootstrapHandler;
+import com.vaadin.server.communication.PortletDummyRequestHandler;
+import com.vaadin.server.communication.PortletListenerNotifier;
+import com.vaadin.server.communication.PortletUIInitHandler;
 import com.vaadin.ui.UI;
 
 public class VaadinPortletService extends VaadinService {
@@ -49,6 +55,35 @@ public class VaadinPortletService extends VaadinService {
         }
     }
 
+    /*
+     * (non-Javadoc)
+     * 
+     * @see
+     * com.vaadin.server.LegacyCommunicationManager.Callback#criticalNotification
+     * (com.vaadin.server.VaadinRequest, com.vaadin.server.VaadinResponse,
+     * java.lang.String, java.lang.String, java.lang.String, java.lang.String)
+     */
+    @Deprecated
+    @Override
+    public void criticalNotification(VaadinRequest request,
+            VaadinResponse response, String cap, String msg, String details,
+            String url) throws IOException {
+        getPortlet().criticalNotification((VaadinPortletRequest) request,
+                (VaadinPortletResponse) response, cap, msg, details, url);
+    }
+
+    @Override
+    protected List<RequestHandler> createRequestHandlers() {
+        List<RequestHandler> handlers = super.createRequestHandlers();
+
+        handlers.add(new PortletUIInitHandler());
+        handlers.add(new PortletListenerNotifier());
+        handlers.add(0, new PortletDummyRequestHandler());
+        handlers.add(0, new PortletBootstrapHandler());
+
+        return handlers;
+    }
+
     /**
      * Retrieves a reference to the portlet associated with this service.
      * 
@@ -163,13 +198,19 @@ public class VaadinPortletService extends VaadinService {
 
     @Override
     protected boolean requestCanCreateSession(VaadinRequest request) {
-        RequestType requestType = getRequestType(request);
-        if (requestType == RequestType.RENDER) {
+        if (!(request instanceof VaadinPortletRequest)) {
+            throw new IllegalArgumentException(
+                    "Request is not a VaadinPortletRequest");
+        }
+
+        PortletRequest portletRequest = ((VaadinPortletRequest) request)
+                .getPortletRequest();
+        if (portletRequest instanceof RenderRequest) {
             // In most cases the first request is a render request that
             // renders the HTML fragment. This should create a Vaadin
             // session unless there is already one.
             return true;
-        } else if (requestType == RequestType.EVENT) {
+        } else if (portletRequest instanceof EventRequest) {
             // A portlet can also be sent an event even though it has not
             // been rendered, e.g. portlet on one page sends an event to a
             // portlet on another page and then moves the user to that page.
@@ -254,8 +295,19 @@ public class VaadinPortletService extends VaadinService {
         return "v-" + portletRequest.getWindowID();
     }
 
+    /*
+     * (non-Javadoc)
+     * 
+     * @see
+     * com.vaadin.server.VaadinService#handleSessionExpired(com.vaadin.server
+     * .VaadinRequest, com.vaadin.server.VaadinResponse)
+     */
     @Override
-    protected BootstrapHandler createBootstrapHandler(VaadinSession session) {
-        return new PortletBootstrapHandler();
+    protected void handleSessionExpired(VaadinRequest request,
+            VaadinResponse response) {
+        // TODO Figure out a better way to deal with
+        // SessionExpiredExceptions
+        getLogger().finest("A user session has expired");
     }
+
 }

server/src/com/vaadin/server/VaadinService.java

@@ -17,6 +17,7 @@
 package com.vaadin.server;
 
 import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 import java.io.Serializable;
 import java.lang.reflect.Constructor;
@@ -24,7 +25,9 @@ import java.lang.reflect.Method;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
+import java.util.List;
 import java.util.Locale;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
@@ -33,9 +36,16 @@ import java.util.logging.Logger;
 
 import javax.portlet.PortletContext;
 import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletResponse;
 
 import com.vaadin.annotations.PreserveOnRefresh;
 import com.vaadin.event.EventRouter;
+import com.vaadin.server.LegacyCommunicationManager.Callback;
+import com.vaadin.server.communication.FileUploadHandler;
+import com.vaadin.server.communication.HeartbeatHandler;
+import com.vaadin.server.communication.PublishedFileHandler;
+import com.vaadin.server.communication.SessionRequestHandler;
+import com.vaadin.server.communication.UidlRequestHandler;
 import com.vaadin.shared.ui.ui.UIConstants;
 import com.vaadin.ui.UI;
 import com.vaadin.util.CurrentInstance;
@@ -49,7 +59,7 @@ import com.vaadin.util.ReflectTools;
  * 
  * @since 7.0
  */
-public abstract class VaadinService implements Serializable {
+public abstract class VaadinService implements Serializable, Callback {
     static final String REINITIALIZING_SESSION_MARKER = VaadinService.class
             .getName() + ".reinitializing";
 
@@ -83,6 +93,8 @@ public abstract class VaadinService implements Serializable {
 
     private ClassLoader classLoader;
 
+    private final Iterable<RequestHandler> requestHandlers;
+
     /**
      * Creates a new vaadin service based on a deployment configuration
      * 
@@ -108,6 +120,33 @@ public abstract class VaadinService implements Serializable {
                                 + classLoaderName, e);
             }
         }
+
+        List<RequestHandler> handlers = createRequestHandlers();
+        Collections.reverse(handlers);
+        requestHandlers = Collections.unmodifiableCollection(handlers);
+
+    }
+
+    /**
+     * Called during initialization to add the request handlers for the service.
+     * Note that the returned list will be reversed so the last handler will be
+     * called first. This enables overriding this method and using add on the
+     * returned list to add a custom request handler which overrides any
+     * predefined handler.
+     * 
+     * @return The list of request handlers used by this service.
+     */
+    protected List<RequestHandler> createRequestHandlers() {
+        ArrayList<RequestHandler> handlers = new ArrayList<RequestHandler>();
+        handlers.add(new SessionRequestHandler());
+        handlers.add(new PublishedFileHandler());
+        handlers.add(new HeartbeatHandler());
+        handlers.add(new FileUploadHandler());
+        handlers.add(new UidlRequestHandler(this));
+        handlers.add(new UnsupportedBrowserHandler());
+        handlers.add(new ConnectorResourceHandler());
+
+        return handlers;
     }
 
     /**
@@ -285,13 +324,6 @@ public abstract class VaadinService implements Serializable {
      */
     public abstract File getBaseDirectory();
 
-    /**
-     * Creates the bootstrap handler that should be used to generate the initial
-     * HTML bootstrapping a new {@link UI} in the given session.
-     */
-    protected abstract BootstrapHandler createBootstrapHandler(
-            VaadinSession session);
-
     /**
      * Adds a listener that gets notified when a new Vaadin service session is
      * initialized for this service.
@@ -1203,4 +1235,125 @@ public abstract class VaadinService implements Serializable {
         }
         CurrentInstance.clearAll();
     }
+
+    /**
+     * Returns the request handlers that are registered with this service. The
+     * iteration order of the returned collection is the same as the order in
+     * which the request handlers will be invoked when a request is handled.
+     * 
+     * @return a collection of request handlers in the order they are invoked
+     * 
+     * @see #createRequestHandlers()
+     * 
+     * @since 7.1
+     */
+    public Iterable<RequestHandler> getRequestHandlers() {
+        return requestHandlers;
+    }
+
+    /**
+     * Handles the incoming request and writes the response into the response
+     * object. Uses {@link #getRequestHandlers()} for handling the request.
+     * 
+     * @param request
+     *            The incoming request
+     * @param response
+     *            The outgoing response
+     * @throws ServiceException
+     *             Any exception that occurs during response handling will be
+     *             wrapped in a ServiceException
+     */
+    public void handleRequest(VaadinRequest request, VaadinResponse response)
+            throws ServiceException {
+        requestStart(request, response);
+
+        VaadinSession vaadinSession = null;
+        try {
+            // Find out the service session this request is related to
+            vaadinSession = findVaadinSession(request);
+            if (vaadinSession == null) {
+                return;
+            }
+
+            for (RequestHandler handler : getRequestHandlers()) {
+                if (handler.handleRequest(vaadinSession, request, response)) {
+                    return;
+                }
+            }
+
+            // Request not handled by any RequestHandler
+            response.sendError(HttpServletResponse.SC_NOT_FOUND,
+                    "Request was not handled by any registered handler.");
+
+        } catch (final SessionExpiredException e) {
+            handleSessionExpired(request, response);
+        } catch (final Throwable e) {
+            handleExceptionDuringRequest(request, response, vaadinSession, e);
+        } finally {
+            requestEnd(request, response, vaadinSession);
+        }
+    }
+
+    private void handleExceptionDuringRequest(VaadinRequest request,
+            VaadinResponse response, VaadinSession vaadinSession, Throwable t)
+            throws ServiceException {
+        if (vaadinSession != null) {
+            vaadinSession.lock();
+        }
+        try {
+            ErrorHandler errorHandler = ErrorEvent
+                    .findErrorHandler(vaadinSession);
+
+            // if this was an UIDL request, response UIDL back to client
+            if (ServletPortletHelper.isUIDLRequest(request)) {
+                SystemMessages ci = getSystemMessages(
+                        ServletPortletHelper.findLocale(null, vaadinSession,
+                                request), request);
+                try {
+                    criticalNotification(request, response,
+                            ci.getInternalErrorCaption(),
+                            ci.getInternalErrorMessage(), null,
+                            ci.getInternalErrorURL());
+                } catch (IOException e) {
+                    // An exception occured while writing the response. Log
+                    // it and continue handling only the original error.
+                    getLogger()
+                            .log(Level.WARNING,
+                                    "Failed to write critical notification response to the client",
+                                    e);
+                }
+                if (errorHandler != null) {
+                    errorHandler.error(new ErrorEvent(t));
+                }
+            } else {
+                if (errorHandler != null) {
+                    errorHandler.error(new ErrorEvent(t));
+                }
+
+                // Re-throw other exceptions
+                throw new ServiceException(t);
+            }
+        } finally {
+            if (vaadinSession != null) {
+                vaadinSession.unlock();
+            }
+        }
+
+    }
+
+    /**
+     * Called when the session has expired and the request handling is therefore
+     * aborted.
+     * 
+     * @param request
+     *            The request
+     * @param response
+     *            The response
+     * @throws ServiceException
+     *             Thrown if there was any problem handling the expiration of
+     *             the session
+     */
+    protected abstract void handleSessionExpired(VaadinRequest request,
+            VaadinResponse response) throws ServiceException;
+
 }

server/src/com/vaadin/server/VaadinServlet.java

@@ -39,41 +39,12 @@ import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 
 import com.vaadin.sass.internal.ScssStylesheet;
-import com.vaadin.server.LegacyCommunicationManager.Callback;
-import com.vaadin.server.communication.FileUploadHandler;
-import com.vaadin.server.communication.HeartbeatHandler;
-import com.vaadin.server.communication.PublishedFileHandler;
-import com.vaadin.server.communication.SessionRequestHandler;
-import com.vaadin.server.communication.UIInitHandler;
-import com.vaadin.server.communication.UidlRequestHandler;
+import com.vaadin.server.communication.ServletUIInitHandler;
 import com.vaadin.util.CurrentInstance;
 
 @SuppressWarnings("serial")
 public class VaadinServlet extends HttpServlet implements Constants {
 
-    private static class AbstractApplicationServletWrapper implements Callback {
-
-        private final VaadinServlet servlet;
-
-        public AbstractApplicationServletWrapper(VaadinServlet servlet) {
-            this.servlet = servlet;
-        }
-
-        @Override
-        public void criticalNotification(VaadinRequest request,
-                VaadinResponse response, String cap, String msg,
-                String details, String outOfSyncURL) throws IOException {
-            servlet.criticalNotification((VaadinServletRequest) request,
-                    ((VaadinServletResponse) response), cap, msg, details,
-                    outOfSyncURL);
-        }
-    }
-
-    // TODO Move some (all?) of the constants to a separate interface (shared
-    // with portlet)
-
-    private final String resourcePath = null;
-
     private VaadinServletService servletService;
 
     /**
@@ -200,7 +171,23 @@ public class VaadinServlet extends HttpServlet implements Constants {
         }
         CurrentInstance.clearAll();
         setCurrent(this);
-        service(createVaadinRequest(request), createVaadinResponse(response));
+
+        VaadinServletRequest vaadinRequest = createVaadinRequest(request);
+        VaadinServletResponse vaadinResponse = createVaadinResponse(response);
+        if (!ensureCookiesEnabled(vaadinRequest, vaadinResponse)) {
+            return;
+        }
+
+        if (isStaticResourceRequest(request)) {
+            serveStaticResources(request, response);
+            return;
+        }
+        try {
+            getService().handleRequest(vaadinRequest, vaadinResponse);
+        } catch (ServiceException e) {
+            throw new ServletException(e);
+        }
+
     }
 
     /**
@@ -239,73 +226,6 @@ public class VaadinServlet extends HttpServlet implements Constants {
         }
     }
 
-    private void service(VaadinServletRequest request,
-            VaadinServletResponse response) throws ServletException,
-            IOException {
-        getService().requestStart(request, response);
-        VaadinSession vaadinSession = null;
-
-        try {
-            AbstractApplicationServletWrapper servletWrapper = new AbstractApplicationServletWrapper(
-                    this);
-
-            RequestType requestType = getRequestType(request);
-            if (!ensureCookiesEnabled(requestType, request, response)) {
-                return;
-            }
-
-            if (requestType == RequestType.STATIC_FILE) {
-                serveStaticResources(request, response);
-                return;
-            }
-
-            try {
-                // Find out the service session this request is related to
-                vaadinSession = getService().findVaadinSession(request);
-                if (vaadinSession == null) {
-                    return;
-                }
-
-                if (requestType == RequestType.PUBLISHED_FILE) {
-                    new PublishedFileHandler().handleRequest(vaadinSession,
-                            request, response);
-                    return;
-                } else if (requestType == RequestType.HEARTBEAT) {
-                    new HeartbeatHandler().handleRequest(vaadinSession,
-                            request, response);
-                    return;
-                } else if (requestType == RequestType.FILE_UPLOAD) {
-                    new FileUploadHandler().handleRequest(vaadinSession,
-                            request, response);
-                    return;
-                } else if (requestType == RequestType.UIDL) {
-                    new UidlRequestHandler(servletWrapper).handleRequest(
-                            vaadinSession, request, response);
-                    return;
-                } else if (requestType == RequestType.BROWSER_DETAILS) {
-                    // Browser details - not related to a specific UI
-                    new UIInitHandler().handleRequest(vaadinSession, request,
-                            response);
-                    return;
-                } else if (new SessionRequestHandler().handleRequest(
-                        vaadinSession, request, response)) {
-                    return;
-                }
-
-                // Request not handled by any RequestHandler -> 404
-                response.sendError(HttpServletResponse.SC_NOT_FOUND);
-
-            } catch (final SessionExpiredException e) {
-                // Session has expired, notify user
-                handleServiceSessionExpired(request, response);
-            } catch (final Throwable e) {
-                handleServiceException(request, response, vaadinSession, e);
-            }
-        } finally {
-            getService().requestEnd(request, response, vaadinSession);
-        }
-    }
-
     private VaadinServletResponse createVaadinResponse(
             HttpServletResponse response) {
         return new VaadinServletResponse(response, getService());
@@ -347,10 +267,9 @@ public class VaadinServlet extends HttpServlet implements Constants {
      * @return false if cookies are disabled, true otherwise
      * @throws IOException
      */
-    private boolean ensureCookiesEnabled(RequestType requestType,
-            VaadinServletRequest request, VaadinServletResponse response)
-            throws IOException {
-        if (requestType == RequestType.UIDL) {
+    private boolean ensureCookiesEnabled(VaadinServletRequest request,
+            VaadinServletResponse response) throws IOException {
+        if (ServletPortletHelper.isUIDLRequest(request)) {
             // In all other but the first UIDL request a cookie should be
             // returned by the browser.
             // This can be removed if cookieless mode (#3228) is supported
@@ -509,44 +428,6 @@ public class VaadinServlet extends HttpServlet implements Constants {
         return resultPath;
     }
 
-    private void handleServiceException(VaadinServletRequest request,
-            VaadinServletResponse response, VaadinSession vaadinSession,
-            Throwable e) throws IOException, ServletException {
-        if (vaadinSession != null) {
-            vaadinSession.lock();
-        }
-        try {
-            ErrorHandler errorHandler = ErrorEvent
-                    .findErrorHandler(vaadinSession);
-
-            // if this was an UIDL request, response UIDL back to client
-            if (getRequestType(request) == RequestType.UIDL) {
-                SystemMessages ci = getService().getSystemMessages(
-                        ServletPortletHelper.findLocale(null, vaadinSession,
-                                request), request);
-                criticalNotification(request, response,
-                        ci.getInternalErrorCaption(),
-                        ci.getInternalErrorMessage(), null,
-                        ci.getInternalErrorURL());
-                if (errorHandler != null) {
-                    errorHandler.error(new ErrorEvent(e));
-                }
-            } else {
-                if (errorHandler != null) {
-                    errorHandler.error(new ErrorEvent(e));
-                }
-
-                // Re-throw other exceptions
-                throw new ServletException(e);
-            }
-        } finally {
-            if (vaadinSession != null) {
-                vaadinSession.unlock();
-            }
-        }
-
-    }
-
     /**
      * A helper method to strip away characters that might somehow be used for
      * XSS attacs. Leaves at least alphanumeric characters intact. Also removes
@@ -591,68 +472,6 @@ public class VaadinServlet extends HttpServlet implements Constants {
         return DEFAULT_THEME_NAME;
     }
 
-    /**
-     * @param request
-     * @param response
-     * @throws IOException
-     * @throws ServletException
-     * 
-     * @deprecated As of 7.0. Will likely change or be removed in a future
-     *             version
-     */
-    @Deprecated
-    void handleServiceSessionExpired(VaadinServletRequest request,
-            VaadinServletResponse response) throws IOException,
-            ServletException {
-
-        try {
-            SystemMessages ci = getService().getSystemMessages(
-                    ServletPortletHelper.findLocale(null, null, request),
-                    request);
-            RequestType requestType = getRequestType(request);
-            if (requestType == RequestType.UIDL) {
-                /*
-                 * Invalidate session (weird to have session if we're saying
-                 * that it's expired, and worse: portal integration will fail
-                 * since the session is not created by the portal.
-                 * 
-                 * Session must be invalidated before criticalNotification as it
-                 * commits the response.
-                 */
-                request.getSession().invalidate();
-
-                // send uidl redirect
-                criticalNotification(request, response,
-                        ci.getSessionExpiredCaption(),
-                        ci.getSessionExpiredMessage(), null,
-                        ci.getSessionExpiredURL());
-
-            } else if (requestType == RequestType.HEARTBEAT) {
-                response.sendError(HttpServletResponse.SC_GONE,
-                        "Session expired");
-            } else {
-                // 'plain' http req - e.g. browser reload;
-                // just go ahead redirect the browser
-                String sessionExpiredURL = ci.getSessionExpiredURL();
-                if (sessionExpiredURL != null) {
-                    response.sendRedirect(sessionExpiredURL);
-                } else {
-                    /*
-                     * Session expired as a result of a standard http request
-                     * and we have nowhere to redirect. Reloading would likely
-                     * cause an endless loop. This can at least happen if
-                     * refreshing a resource when the session has expired.
-                     */
-                    response.sendError(HttpServletResponse.SC_GONE,
-                            "Session expired");
-                }
-            }
-        } catch (SystemMessageException ee) {
-            throw new ServletException(ee);
-        }
-
-    }
-
     private void handleServiceSecurityException(VaadinServletRequest request,
             VaadinServletResponse response) throws IOException,
             ServletException {
@@ -664,14 +483,13 @@ public class VaadinServlet extends HttpServlet implements Constants {
              */
             SystemMessages ci = getService().getSystemMessages(
                     request.getLocale(), request);
-            RequestType requestType = getRequestType(request);
-            if (requestType == RequestType.UIDL) {
+            if (ServletPortletHelper.isUIDLRequest(request)) {
                 // send uidl redirect
                 criticalNotification(request, response,
                         ci.getCommunicationErrorCaption(),
                         ci.getCommunicationErrorMessage(),
                         INVALID_SECURITY_KEY_MSG, ci.getCommunicationErrorURL());
-            } else if (requestType == RequestType.HEARTBEAT) {
+            } else if (ServletPortletHelper.isHeartbeatRequest(request)) {
                 response.sendError(HttpServletResponse.SC_FORBIDDEN,
                         "Forbidden");
             } else {
@@ -1056,10 +874,12 @@ public class VaadinServlet extends HttpServlet implements Constants {
     /**
      * 
      * @author Vaadin Ltd
-     * @since 7.0.0
+     * @since 7.0
      * 
-     * @deprecated As of 7.0. Will likely change or be removed in a future
-     *             version
+     * @deprecated As of 7.0. This is no longer used and only provided for
+     *             backwards compatibility. Each {@link RequestHandler} can
+     *             individually decide whether it wants to handle a request or
+     *             not.
      */
     @Deprecated
     protected enum RequestType {
@@ -1070,8 +890,10 @@ public class VaadinServlet extends HttpServlet implements Constants {
      * @param request
      * @return
      * 
-     * @deprecated As of 7.0. Will likely change or be removed in a future
-     *             version
+     * @deprecated As of 7.0. This is no longer used and only provided for
+     *             backwards compatibility. Each {@link RequestHandler} can
+     *             individually decide whether it wants to handle a request or
+     *             not.
      */
     @Deprecated
     protected RequestType getRequestType(VaadinServletRequest request) {
@@ -1079,7 +901,7 @@ public class VaadinServlet extends HttpServlet implements Constants {
             return RequestType.FILE_UPLOAD;
         } else if (ServletPortletHelper.isPublishedFileRequest(request)) {
             return RequestType.PUBLISHED_FILE;
-        } else if (isBrowserDetailsRequest(request)) {
+        } else if (ServletUIInitHandler.isUIInitRequest(request)) {
             return RequestType.BROWSER_DETAILS;
         } else if (ServletPortletHelper.isUIDLRequest(request)) {
             return RequestType.UIDL;
@@ -1094,12 +916,7 @@ public class VaadinServlet extends HttpServlet implements Constants {
 
     }
 
-    private static boolean isBrowserDetailsRequest(HttpServletRequest request) {
-        return "POST".equals(request.getMethod())
-                && request.getParameter("v-browserDetails") != null;
-    }
-
-    private boolean isStaticResourceRequest(HttpServletRequest request) {
+    protected boolean isStaticResourceRequest(HttpServletRequest request) {
         String pathInfo = request.getPathInfo();
         if (pathInfo == null || pathInfo.length() <= 10) {
             return false;
@@ -1235,4 +1052,5 @@ public class VaadinServlet extends HttpServlet implements Constants {
     private static final Logger getLogger() {
         return Logger.getLogger(VaadinServlet.class.getName());
     }
+
 }

server/src/com/vaadin/server/VaadinServletService.java

@@ -17,15 +17,19 @@
 package com.vaadin.server;
 
 import java.io.File;
+import java.io.IOException;
 import java.io.InputStream;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.util.List;
+import java.util.logging.Logger;
 
 import javax.servlet.ServletContext;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
 
-import com.vaadin.server.VaadinServlet.RequestType;
 import com.vaadin.server.communication.ServletBootstrapHandler;
+import com.vaadin.server.communication.ServletUIInitHandler;
 import com.vaadin.ui.UI;
 
 public class VaadinServletService extends VaadinService {
@@ -47,6 +51,31 @@ public class VaadinServletService extends VaadinService {
         }
     }
 
+    /*
+     * (non-Javadoc)
+     * 
+     * @see
+     * com.vaadin.server.LegacyCommunicationManager.Callback#criticalNotification
+     * (com.vaadin.server.VaadinRequest, com.vaadin.server.VaadinResponse,
+     * java.lang.String, java.lang.String, java.lang.String, java.lang.String)
+     */
+    @Deprecated
+    @Override
+    public void criticalNotification(VaadinRequest request,
+            VaadinResponse response, String cap, String msg, String details,
+            String url) throws IOException {
+        getServlet().criticalNotification((VaadinServletRequest) request,
+                (VaadinServletResponse) response, cap, msg, details, url);
+    }
+
+    @Override
+    protected List<RequestHandler> createRequestHandlers() {
+        List<RequestHandler> handlers = super.createRequestHandlers();
+        handlers.add(0, new ServletBootstrapHandler());
+        handlers.add(new ServletUIInitHandler());
+        return handlers;
+    }
+
     /**
      * Retrieves a reference to the servlet associated with this service.
      * 
@@ -135,12 +164,11 @@ public class VaadinServletService extends VaadinService {
 
     @Override
     protected boolean requestCanCreateSession(VaadinRequest request) {
-        RequestType requestType = getRequestType(request);
-        if (requestType == RequestType.BROWSER_DETAILS) {
+        if (ServletUIInitHandler.isUIInitRequest(request)) {
             // This is the first request if you are embedding by writing the
             // embedding code yourself
             return true;
-        } else if (requestType == RequestType.OTHER) {
+        } else if (isOtherRequest(request)) {
             /*
              * I.e URIs that are not RPC calls or static (theme) files.
              */
@@ -150,25 +178,15 @@ public class VaadinServletService extends VaadinService {
         return false;
     }
 
-    /**
-     * Gets the request type for the request.
-     * 
-     * @param request
-     *            the request to get a request type for
-     * @return the request type
-     * 
-     * @deprecated As of 7.0. Will likely change or be removed in a future
-     *             version
-     */
-    @Deprecated
-    protected RequestType getRequestType(VaadinRequest request) {
-        RequestType type = (RequestType) request.getAttribute(RequestType.class
-                .getName());
-        if (type == null) {
-            type = getServlet().getRequestType((VaadinServletRequest) request);
-            request.setAttribute(RequestType.class.getName(), type);
-        }
-        return type;
+    private boolean isOtherRequest(VaadinRequest request) {
+        // TODO This should be refactored in some way. It should not be
+        // necessary to check all these types.
+        return (!ServletPortletHelper.isAppRequest(request)
+                && !ServletUIInitHandler.isUIInitRequest(request)
+                && !ServletPortletHelper.isFileUploadRequest(request)
+                && !ServletPortletHelper.isHeartbeatRequest(request)
+                && !ServletPortletHelper.isPublishedFileRequest(request) && !ServletPortletHelper
+                    .isUIDLRequest(request));
     }
 
     @Override
@@ -235,8 +253,73 @@ public class VaadinServletService extends VaadinService {
         return appId;
     }
 
+    /*
+     * (non-Javadoc)
+     * 
+     * @see
+     * com.vaadin.server.VaadinService#handleSessionExpired(com.vaadin.server
+     * .VaadinRequest, com.vaadin.server.VaadinResponse)
+     */
     @Override
-    protected BootstrapHandler createBootstrapHandler(VaadinSession session) {
-        return new ServletBootstrapHandler();
+    protected void handleSessionExpired(VaadinRequest request,
+            VaadinResponse response) throws ServiceException {
+        if (!(request instanceof VaadinServletRequest)) {
+            throw new ServiceException(new IllegalArgumentException(
+                    "handleSessionExpired called with a non-VaadinServletRequest: "
+                            + request.getClass().getName()));
+        }
+
+        VaadinServletRequest servletRequest = (VaadinServletRequest) request;
+        VaadinServletResponse servletResponse = (VaadinServletResponse) response;
+
+        try {
+            SystemMessages ci = getSystemMessages(
+                    ServletPortletHelper.findLocale(null, null, request),
+                    request);
+            if (ServletPortletHelper.isUIDLRequest(request)) {
+                /*
+                 * Invalidate session (weird to have session if we're saying
+                 * that it's expired)
+                 * 
+                 * Session must be invalidated before criticalNotification as it
+                 * commits the response.
+                 */
+                servletRequest.getSession().invalidate();
+
+                // send uidl redirect
+                criticalNotification(request, response,
+                        ci.getSessionExpiredCaption(),
+                        ci.getSessionExpiredMessage(), null,
+                        ci.getSessionExpiredURL());
+
+            } else if (ServletPortletHelper.isHeartbeatRequest(request)) {
+                response.sendError(HttpServletResponse.SC_GONE,
+                        "Session expired");
+            } else {
+                // 'plain' http req - e.g. browser reload;
+                // just go ahead redirect the browser
+                String sessionExpiredURL = ci.getSessionExpiredURL();
+                if (sessionExpiredURL != null) {
+                    servletResponse.sendRedirect(sessionExpiredURL);
+                } else {
+                    /*
+                     * Session expired as a result of a standard http request
+                     * and we have nowhere to redirect. Reloading would likely
+                     * cause an endless loop. This can at least happen if
+                     * refreshing a resource when the session has expired.
+                     */
+                    response.sendError(HttpServletResponse.SC_GONE,
+                            "Session expired");
+                }
+            }
+        } catch (IOException e) {
+            throw new ServiceException(e);
+        }
+
     }
+
+    private static final Logger getLogger() {
+        return Logger.getLogger(VaadinServletService.class.getName());
+    }
+
 }

server/src/com/vaadin/server/communication/FileUploadHandler.java

@@ -217,6 +217,9 @@ public class FileUploadHandler implements RequestHandler {
     @Override
     public boolean handleRequest(VaadinSession session, VaadinRequest request,
             VaadinResponse response) throws IOException {
+        if (!ServletPortletHelper.isFileUploadRequest(request)) {
+            return false;
+        }
 
         /*
          * URI pattern: APP/UPLOAD/[UIID]/[PID]/[NAME]/[SECKEY] See

server/src/com/vaadin/server/communication/HeartbeatHandler.java

@@ -20,10 +20,12 @@ import java.io.IOException;
 
 import javax.servlet.http.HttpServletResponse;
 
+import com.vaadin.server.ServletPortletHelper;
 import com.vaadin.server.SynchronizedRequestHandler;
 import com.vaadin.server.VaadinRequest;
 import com.vaadin.server.VaadinResponse;
 import com.vaadin.server.VaadinSession;
+import com.vaadin.shared.ui.ui.UIConstants;
 import com.vaadin.ui.UI;
 
 /**
@@ -49,6 +51,10 @@ public class HeartbeatHandler extends SynchronizedRequestHandler {
     @Override
     public boolean synchronizedHandleRequest(VaadinSession session,
             VaadinRequest request, VaadinResponse response) throws IOException {
+        if (!ServletPortletHelper.isHeartbeatRequest(request)) {
+            return false;
+        }
+
         UI ui = session.getService().findUI(request);
         if (ui != null) {
             ui.setLastHeartbeatTimestamp(System.currentTimeMillis());

server/src/com/vaadin/server/communication/PortletDummyRequestHandler.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2000-2013 Vaadin Ltd.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.server.communication;
+
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintWriter;
+
+import javax.portlet.PortletResponse;
+import javax.portlet.ResourceRequest;
+import javax.portlet.ResourceResponse;
+
+import com.vaadin.server.RequestHandler;
+import com.vaadin.server.VaadinPortletResponse;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.server.VaadinResponse;
+import com.vaadin.server.VaadinSession;
+
+/**
+ * Request handler which provides a dummy HTML response to any resource request
+ * with the resource id DUMMY.
+ * 
+ * @author Vaadin Ltd
+ * @since 7.1
+ */
+public class PortletDummyRequestHandler implements RequestHandler {
+
+    @Override
+    public boolean handleRequest(VaadinSession session, VaadinRequest request,
+            VaadinResponse response) throws IOException {
+        if (!isDummyRequest(request)) {
+            return false;
+        }
+
+        /*
+         * This dummy page is used by action responses to redirect to, in order
+         * to prevent the boot strap code from being rendered into strange
+         * places such as iframes.
+         */
+        PortletResponse portletResponse = ((VaadinPortletResponse) response)
+                .getPortletResponse();
+        if (portletResponse instanceof ResourceResponse) {
+            ((ResourceResponse) portletResponse).setContentType("text/html");
+        }
+
+        final OutputStream out = ((ResourceResponse) response)
+                .getPortletOutputStream();
+        final PrintWriter outWriter = new PrintWriter(new BufferedWriter(
+                new OutputStreamWriter(out, "UTF-8")));
+        outWriter.print("<html><body>dummy page</body></html>");
+        outWriter.close();
+
+        return true;
+    }
+
+    public static boolean isDummyRequest(VaadinRequest request) {
+        ResourceRequest resourceRequest = PortletUIInitHandler
+                .getResourceRequest(request);
+        if (resourceRequest == null) {
+            return false;
+        }
+
+        return resourceRequest.getResourceID() != null
+                && resourceRequest.getResourceID().equals("DUMMY");
+    }
+
+}

server/src/com/vaadin/server/communication/PortletUIInitHandler.java

@@ -0,0 +1,63 @@
+/*
+ * Copyright 2000-2013 Vaadin Ltd.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.server.communication;
+
+import javax.portlet.PortletRequest;
+import javax.portlet.ResourceRequest;
+
+import com.vaadin.server.VaadinPortletRequest;
+import com.vaadin.server.VaadinRequest;
+
+public class PortletUIInitHandler extends UIInitHandler {
+
+    @Override
+    protected boolean isInitRequest(VaadinRequest request) {
+        return isUIInitRequest(request);
+    }
+
+    public static boolean isUIInitRequest(VaadinRequest request) {
+        ResourceRequest resourceRequest = getResourceRequest(request);
+        if (resourceRequest == null) {
+            return false;
+        }
+
+        return UIInitHandler.BROWSER_DETAILS_PARAMETER.equals(resourceRequest
+                .getResourceID());
+    }
+
+    /**
+     * Returns the {@link ResourceRequest} for the given request or null if none
+     * could be found.
+     * 
+     * @param request
+     *            The original request, must be a {@link VaadinPortletRequest}
+     * @return The resource request from the request parameter or null
+     */
+    static ResourceRequest getResourceRequest(VaadinRequest request) {
+        if (!(request instanceof VaadinPortletRequest)) {
+            throw new IllegalArgumentException(
+                    "Request must a VaadinPortletRequest");
+        }
+        PortletRequest portletRequest = ((VaadinPortletRequest) request)
+                .getPortletRequest();
+        if (!(portletRequest instanceof ResourceRequest)) {
+            return null;
+        }
+
+        return (ResourceRequest) portletRequest;
+
+    }
+}

server/src/com/vaadin/server/communication/PublishedFileHandler.java

@@ -28,6 +28,7 @@ import com.vaadin.annotations.StyleSheet;
 import com.vaadin.server.Constants;
 import com.vaadin.server.LegacyCommunicationManager;
 import com.vaadin.server.RequestHandler;
+import com.vaadin.server.ServletPortletHelper;
 import com.vaadin.server.VaadinRequest;
 import com.vaadin.server.VaadinResponse;
 import com.vaadin.server.VaadinSession;
@@ -55,6 +56,9 @@ public class PublishedFileHandler implements RequestHandler {
     @Override
     public boolean handleRequest(VaadinSession session, VaadinRequest request,
             VaadinResponse response) throws IOException {
+        if (!ServletPortletHelper.isPublishedFileRequest(request)) {
+            return false;
+        }
 
         String pathInfo = request.getPathInfo();
         // + 2 to also remove beginning and ending slashes

server/src/com/vaadin/server/communication/ServletUIInitHandler.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2000-2013 Vaadin Ltd.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.server.communication;
+
+import com.vaadin.server.VaadinRequest;
+
+public class ServletUIInitHandler extends UIInitHandler {
+
+    @Override
+    protected boolean isInitRequest(VaadinRequest request) {
+        return isUIInitRequest(request);
+    }
+
+    public static boolean isUIInitRequest(VaadinRequest request) {
+        return "POST".equals(request.getMethod())
+                && request
+                        .getParameter(UIInitHandler.BROWSER_DETAILS_PARAMETER) != null;
+    }
+
+}

server/src/com/vaadin/server/communication/SessionRequestHandler.java

@@ -22,6 +22,7 @@ import com.vaadin.server.RequestHandler;
 import com.vaadin.server.VaadinRequest;
 import com.vaadin.server.VaadinResponse;
 import com.vaadin.server.VaadinSession;
+import com.vaadin.shared.ApplicationConstants;
 
 /**
  * Handles a request by passing it to each registered {@link RequestHandler} in
@@ -50,6 +51,13 @@ public class SessionRequestHandler implements RequestHandler {
     @Override
     public boolean handleRequest(VaadinSession session, VaadinRequest request,
             VaadinResponse response) throws IOException {
+        String pathInfo = request.getPathInfo();
+        if (pathInfo.startsWith("/" + ApplicationConstants.APP_PATH + "/")) {
+            // /<APP_PATH>/ is reserved for Vaadin internal use and these
+            // requests should not be passed to session request handlers
+            return false;
+        }
+
         // Use a copy to avoid ConcurrentModificationException
         session.lock();
         ArrayList<RequestHandler> requestHandlers;

server/src/com/vaadin/server/communication/UIInitHandler.java

@@ -49,11 +49,18 @@ import com.vaadin.ui.UI;
  * @author Vaadin Ltd
  * @since 7.1
  */
-public class UIInitHandler extends SynchronizedRequestHandler {
+public abstract class UIInitHandler extends SynchronizedRequestHandler {
+
+    public static final String BROWSER_DETAILS_PARAMETER = "v-browserDetails";
+
+    protected abstract boolean isInitRequest(VaadinRequest request);
 
     @Override
     public boolean synchronizedHandleRequest(VaadinSession session,
             VaadinRequest request, VaadinResponse response) throws IOException {
+        if (!isInitRequest(request)) {
+            return false;
+        }
 
         // NOTE! GateIn requires, for some weird reason, getOutputStream
         // to be used instead of getWriter() (it seems to interpret

server/src/com/vaadin/server/communication/UidlRequestHandler.java

@@ -32,6 +32,7 @@ import com.vaadin.server.Constants;
 import com.vaadin.server.LegacyCommunicationManager;
 import com.vaadin.server.LegacyCommunicationManager.Callback;
 import com.vaadin.server.LegacyCommunicationManager.InvalidUIDLSecurityKeyException;
+import com.vaadin.server.ServletPortletHelper;
 import com.vaadin.server.SynchronizedRequestHandler;
 import com.vaadin.server.VaadinRequest;
 import com.vaadin.server.VaadinResponse;
@@ -53,6 +54,8 @@ import com.vaadin.ui.UI;
  */
 public class UidlRequestHandler extends SynchronizedRequestHandler {
 
+    public static final String UIDL_PATH = "UIDL/";
+
     private Callback criticalNotifier;
 
     private ServerRpcHandler rpcHandler = new ServerRpcHandler();
@@ -64,7 +67,9 @@ public class UidlRequestHandler extends SynchronizedRequestHandler {
     @Override
     public boolean synchronizedHandleRequest(VaadinSession session,
             VaadinRequest request, VaadinResponse response) throws IOException {
-
+        if (!ServletPortletHelper.isUIDLRequest(request)) {
+            return false;
+        }
         UI uI = session.getService().findUI(request);
 
         checkWidgetsetVersion(request);