com.vaadin.server

Class GAEVaadinServlet

java.lang.Object

javax.servlet.GenericServlet

javax.servlet.http.HttpServlet

com.vaadin.server.VaadinServlet

com.vaadin.server.GAEVaadinServlet

All Implemented Interfaces:

Constants, Serializable, javax.servlet.Servlet, javax.servlet.ServletConfig

public class GAEVaadinServlet
extends VaadinServlet

ApplicationServlet to be used when deploying to Google App Engine, in web.xml:

      <servlet>
              <servlet-name>HelloWorld</servlet-name>
              <servlet-class>com.vaadin.server.GAEApplicationServlet</servlet-class>
              <init-param>
                      <param-name>UI</param-name>
                      <param-value>com.vaadin.demo.HelloWorld</param-value>
              </init-param>
      </servlet>
 

Session support must be enabled in appengine-web.xml:

      <sessions-enabled>true</sessions-enabled>
 

Appengine datastore cleanup can be invoked by calling one of the applications with an additional path "/CLEAN". This can be set up as a cron-job in cron.xml (see appengine documentation for more information):

 <cronentries>
   <cron>
     <url>/HelloWorld/CLEAN</url>
     <description>Clean up sessions</description>
     <schedule>every 2 hours</schedule>
   </cron>
 </cronentries>
 

It is recommended (but not mandatory) to extract themes and widgetsets and have App Engine server these statically. Extract VAADIN folder (and it's contents) 'next to' the WEB-INF folder, and add the following to appengine-web.xml:

      <static-files>
           <include path="/VAADIN/**" />
      </static-files>
 

Additional limitations:

• Do not change application state when serving an ApplicationResource.
• Avoid changing application state in transaction handlers, unless you're confident you fully understand the synchronization issues in App Engine.
• The application remains locked while uploading - no progressbar is possible.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.vaadin.server.VaadinServlet

VaadinServlet.RequestType

Field Summary

Fields inherited from interface com.vaadin.server.Constants

ATMOSPHERE_MISSING_ERROR, CANNOT_ACQUIRE_CLASSLOADER_SEVERE, DEFAULT_BUFFER_SIZE, DEFAULT_THEME_CACHETIME, DEFAULT_THEME_NAME, DEFAULT_WIDGETSET, ERROR_NO_UI_FOUND, INVALID_ATMOSPHERE_VERSION_WARNING, INVALID_SECURITY_KEY_MSG, MAX_BUFFER_SIZE, NOT_PRODUCTION_MODE_INFO, PARAMETER_VAADIN_RESOURCES, PARAMETER_WIDGETSET, PORTAL_PARAMETER_VAADIN_RESOURCE_PATH, PORTAL_PARAMETER_VAADIN_THEME, PORTAL_PARAMETER_VAADIN_WIDGETSET, PORTLET_CONTEXT, PUSH_NOT_SUPPORTED_ERROR, REQUIRED_ATMOSPHERE_RUNTIME_VERSION, SERVLET_PARAMETER_CLOSE_IDLE_SESSIONS, SERVLET_PARAMETER_DISABLE_XSRF_PROTECTION, SERVLET_PARAMETER_HEARTBEAT_INTERVAL, SERVLET_PARAMETER_LEGACY_DESIGN_PREFIX, SERVLET_PARAMETER_LEGACY_PROPERTY_TOSTRING, SERVLET_PARAMETER_PRODUCTION_MODE, SERVLET_PARAMETER_PUSH_MODE, SERVLET_PARAMETER_PUSH_SUSPEND_TIMEOUT_LONGPOLLING, SERVLET_PARAMETER_RESOURCE_CACHE_TIME, SERVLET_PARAMETER_SENDURLSASPARAMETERS, SERVLET_PARAMETER_SYNC_ID_CHECK, SERVLET_PARAMETER_UI_PROVIDER, THEME_DIR_PATH, URL_PARAMETER_THEME, WARNING_HEARTBEAT_INTERVAL_NOT_NUMERIC, WARNING_LEGACY_PROPERTY_TOSTRING, WARNING_PUSH_MODE_NOT_RECOGNIZED, WARNING_RESOURCE_CACHING_TIME_NOT_NUMERIC, WARNING_UNKNOWN_LEGACY_PROPERTY_TOSTRING_VALUE, WARNING_XSRF_PROTECTION_DISABLED, WIDGETSET_DIR_PATH, WIDGETSET_MISMATCH_INFO

Constructor Summary

Constructors

Constructor and Description
GAEVaadinServlet()

Method Summary

Modifier and Type	Method and Description
protected VaadinSession	getApplicationContext(javax.servlet.http.HttpServletRequest request, com.google.appengine.api.memcache.MemcacheService memcache)
protected int	getMaxInactiveIntervalSeconds(javax.servlet.http.HttpSession session) Returns the maximum inactive time for a session.
protected void	sendCriticalErrorNotification(VaadinServletRequest request, VaadinServletResponse response)
protected void	sendDeadlineExceededNotification(VaadinServletRequest request, VaadinServletResponse response)
protected void	sendNotSerializableNotification(VaadinServletRequest request, VaadinServletResponse response)
protected void	service(javax.servlet.http.HttpServletRequest unwrappedRequest, javax.servlet.http.HttpServletResponse unwrappedResponse) Receives standard HTTP requests from the public service method and dispatches them.

Methods inherited from class com.vaadin.server.VaadinServlet

allowServePrecompressedResource, createDeploymentConfiguration, createServletService, createVaadinRequest, criticalNotification, destroy, findResourceURL, getApplicationUrl, getCacheTime, getCurrent, getDefaultTheme, getLastPathParameter, getRequestType, getResourcePath, getService, handleContextRootWithoutSlash, init, isAllowedVAADINResourceUrl, isStaticResourceRequest, safeEscapeForHtml, serveStaticResources, serveStaticResourcesInVAADIN, servletInitialized, stripSpecialChars, writeStaticResourceResponse

Methods inherited from class javax.servlet.http.HttpServlet

doDelete, doGet, doHead, doOptions, doPost, doPut, doTrace, getLastModified, service

Methods inherited from class javax.servlet.GenericServlet

getInitParameter, getInitParameterNames, getServletConfig, getServletContext, getServletInfo, getServletName, init, log, log

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GAEVaadinServlet

public GAEVaadinServlet()

Method Detail

sendDeadlineExceededNotification

protected void sendDeadlineExceededNotification(VaadinServletRequest request,
                                                VaadinServletResponse response)
                                         throws IOException

Throws:

IOException

sendNotSerializableNotification

protected void sendNotSerializableNotification(VaadinServletRequest request,
                                               VaadinServletResponse response)
                                        throws IOException

Throws:

IOException

sendCriticalErrorNotification

protected void sendCriticalErrorNotification(VaadinServletRequest request,
                                             VaadinServletResponse response)
                                      throws IOException

Throws:

IOException

service

protected void service(javax.servlet.http.HttpServletRequest unwrappedRequest,
                       javax.servlet.http.HttpServletResponse unwrappedResponse)
                throws javax.servlet.ServletException,
                       IOException

Description copied from class: VaadinServlet

Receives standard HTTP requests from the public service method and dispatches them.

Overrides:

service in class VaadinServlet

Parameters:

unwrappedRequest - the object that contains the request the client made of the servlet.

unwrappedResponse - the object that contains the response the servlet returns to the client.

Throws:

javax.servlet.ServletException - if an input or output error occurs while the servlet is handling the TRACE request.

IOException - if the request for the TRACE cannot be handled.

getMaxInactiveIntervalSeconds

protected int getMaxInactiveIntervalSeconds(javax.servlet.http.HttpSession session)

Returns the maximum inactive time for a session. This is used for handling the expiration of session related information in caches etc.

Parameters:

session -

Returns:

inactive timeout in seconds, greater than zero

getApplicationContext

protected VaadinSession getApplicationContext(javax.servlet.http.HttpServletRequest request,
                                              com.google.appengine.api.memcache.MemcacheService memcache)
                                       throws javax.servlet.ServletException

Throws:

javax.servlet.ServletException