com.vaadin.server
Class VaadinService

java.lang.Object
  com.vaadin.server.VaadinService

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

VaadinPortletService, VaadinServletService

public abstract class VaadinService
extends java.lang.Object
implements java.io.Serializable

Provide deployment specific settings that are required outside terminal specific code.

Since:

7.0

Author:

Vaadin Ltd.

See Also:

Serialized Form

Field Summary

static java.lang.String	URL_PARAMETER_CLOSE_APPLICATION Deprecated. As of 7.0. Only supported for LegacyApplication.
static java.lang.String	URL_PARAMETER_RESTART_APPLICATION Deprecated. As of 7.0. Only supported for LegacyApplication.

Constructor Summary

VaadinService(DeploymentConfiguration deploymentConfiguration)
Creates a new vaadin service based on a deployment configuration

Method Summary

java.util.concurrent.Future<java.lang.Void>	accessSession(VaadinSession session, java.lang.Runnable runnable) Implementation for VaadinSession.access(Runnable).
void	addServiceDestroyListener(ServiceDestroyListener listener) Adds a service destroy listener that gets notified when this service is destroyed.
void	addSessionDestroyListener(SessionDestroyListener listener) Adds a listener that gets notified when a Vaadin service session that has been initialized for this service is destroyed.
void	addSessionInitListener(SessionInitListener listener) Adds a listener that gets notified when a new Vaadin service session is initialized for this service.
void	closeSession(VaadinSession session) Sets the given session to be closed and all its UI state to be discarded at the end of the current request, or at the end of the next request if there is no ongoing one.
static java.lang.String	createCriticalNotificationJSON(java.lang.String caption, java.lang.String message, java.lang.String details, java.lang.String url) Creates a JSON message which, when sent to client as-is, will cause a critical error to be shown with the given details.
protected java.util.List<RequestHandler>	createRequestHandlers() Called during initialization to add the request handlers for the service.
protected VaadinSession	createVaadinSession(VaadinRequest request) Creates a new Vaadin session for this service and request
void	criticalNotification(VaadinRequest request, VaadinResponse response, java.lang.String caption, java.lang.String message, java.lang.String details, java.lang.String url) Deprecated. As of 7.0. Will likely change or be removed in a future version
void	destroy() Called when the servlet, portlet or similar for this service is being destroyed.
void	ensureAccessQueuePurged(VaadinSession session) Makes sure the pending access queue is purged for the provided session.
boolean	ensurePushAvailable() Enables push if push support is available and push has not yet been enabled.
UI	findUI(VaadinRequest request) Finds the UI that belongs to the provided request.
VaadinSession	findVaadinSession(VaadinRequest request) Attempts to find a Vaadin service session associated with this request.
void	fireSessionDestroy(VaadinSession vaadinSession) Handles destruction of the given session.
protected java.net.URL	getApplicationUrl(VaadinRequest request) Deprecated. As of 7.0. Only used to support LegacyApplication.
abstract java.io.File	getBaseDirectory() Returns the context base directory.
java.lang.ClassLoader	getClassLoader() Gets the class loader to use for loading classes loaded by name, e.g.
abstract java.lang.String	getConfiguredTheme(VaadinRequest request) Gets the theme that is configured for this deployment, e.g.
abstract java.lang.String	getConfiguredWidgetset(VaadinRequest request) Gets the widgetset that is configured for this deployment, e.g.
static VaadinService	getCurrent() Gets the currently used Vaadin service.
static VaadinRequest	getCurrentRequest() Gets the currently processed Vaadin request.
static VaadinResponse	getCurrentResponse() Gets the currently processed Vaadin response.
DeploymentConfiguration	getDeploymentConfiguration() Gets the deployment configuration.
protected VaadinSession	getExistingSession(VaadinRequest request, boolean allowSessionCreation)
abstract java.lang.String	getMainDivId(VaadinSession session, VaadinRequest request, java.lang.Class<? extends UI> uiClass) Creates and returns a unique ID for the DIV where the UI is to be rendered.
abstract java.lang.String	getMimeType(java.lang.String resourceName) Returns the MIME type of the specified file, or null if the MIME type is not known.
java.lang.Iterable<RequestHandler>	getRequestHandlers() Returns the request handlers that are registered with this service.
abstract java.lang.String	getServiceName() Gets a unique name for this service.
protected java.lang.String	getSessionAttributeName() Returns the name used for storing the VaadinSession in the underlying HTTP session
protected java.util.concurrent.locks.Lock	getSessionLock(WrappedSession wrappedSession) Gets the lock instance used to lock the VaadinSession associated with the given wrapped session.
abstract java.lang.String	getStaticFileLocation(VaadinRequest request) Return the URL from where static files, e.g.
SystemMessages	getSystemMessages(java.util.Locale locale, VaadinRequest request) Gets the system message to use for a specific locale.
SystemMessagesProvider	getSystemMessagesProvider() Gets the system messages provider currently defined for this service.
abstract java.io.InputStream	getThemeResourceAsStream(UI uI, java.lang.String themeName, java.lang.String resource) TODO PUSH Document TODO Pass UI or VaadinSession?
void	handleRequest(VaadinRequest request, VaadinResponse response) Handles the incoming request and writes the response into the response object.
protected void	handleSessionExpired(VaadinRequest request, VaadinResponse response) Called when the session has expired and the request handling is therefore aborted.
void	init() Initializes this service.
protected boolean	isAtmosphereAvailable() Checks whether Atmosphere is avilable for use
static boolean	isCsrfTokenValid(VaadinSession session, java.lang.String requestToken) Verifies that the given CSRF token (aka double submit cookie) is valid for the given session.
static boolean	isOtherSessionLocked(VaadinSession session) Checks whether there might be some VaadinSession other than the provided one for which the current thread holds a lock.
abstract boolean	isStandalone(VaadinRequest request) Checks whether the UI will be rendered on its own in the browser or whether it will be included into some other context.
protected VaadinSession	loadSession(WrappedSession wrappedSession) Called when the VaadinSession should be loaded from the underlying HTTP session
protected void	lockSession(WrappedSession wrappedSession) Locks the given session for this service instance.
boolean	preserveUIOnRefresh(UIProvider provider, UICreateEvent event) Check if the given UI should be associated with the window.name so that it can be re-used if the browser window is reloaded.
protected VaadinSession	readFromHttpSession(WrappedSession wrappedSession) Performs the actual read of the VaadinSession from the underlying HTTP session after sanity checks have been performed.
static void	reinitializeSession(VaadinRequest request) Discards the current session and creates a new session with the same contents.
protected void	removeFromHttpSession(WrappedSession wrappedSession) Performs the actual removal of the VaadinSession from the underlying HTTP session after sanity checks have been performed
void	removeServiceDestroyListener(ServiceDestroyListener listener) Removes a service destroy listener that was previously added with addServiceDestroyListener(ServiceDestroyListener).
void	removeSession(WrappedSession wrappedSession) Called when the VaadinSession should be removed from the underlying HTTP session
void	removeSessionDestroyListener(SessionDestroyListener listener) Removes a Vaadin service session destroy listener from this service.
void	removeSessionInitListener(SessionInitListener listener) Removes a Vaadin service session initialization listener from this service.
protected abstract boolean	requestCanCreateSession(VaadinRequest request) Checks whether it's valid to create a new service session as a result of the given request.
void	requestEnd(VaadinRequest request, VaadinResponse response, VaadinSession session) Called after the framework has handled a request and the response has been written.
void	requestStart(VaadinRequest request, VaadinResponse response) Called before the framework starts handling a request
void	runPendingAccessTasks(VaadinSession session) Purges the queue of pending access invocations enqueued with VaadinSession.access(Runnable).
void	setClassLoader(java.lang.ClassLoader classLoader) Sets the class loader to use for loading classes loaded by name, e.g.
static void	setCurrent(VaadinService service) Sets the given Vaadin service as the current service.
void	setCurrentInstances(VaadinRequest request, VaadinResponse response) Sets the this Vaadin service as the current service and also sets the current Vaadin request and Vaadin response.
protected void	setDefaultClassLoader() Tries to acquire default class loader and sets it as a class loader for this VaadinService if found.
void	setSystemMessagesProvider(SystemMessagesProvider systemMessagesProvider) Sets the system messages provider to use for getting system messages to display to users of this service.
protected void	storeSession(VaadinSession session, WrappedSession wrappedSession) Called when the VaadinSession should be stored.
protected void	unlockSession(WrappedSession wrappedSession) Releases the lock for the given session for this service instance.
static void	verifyNoOtherSessionLocked(VaadinSession session) Checks that another VaadinSession instance is not locked.
void	writeStringResponse(VaadinResponse response, java.lang.String contentType, java.lang.String reponseString) Writes the given string as a response using the given content type.
protected void	writeToHttpSession(WrappedSession wrappedSession, VaadinSession session) Performs the actual write of the VaadinSession to the underlying HTTP session after sanity checks have been performed.

Methods inherited from class java.lang.Object

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

Field Detail

URL_PARAMETER_RESTART_APPLICATION

@Deprecated
public static final java.lang.String URL_PARAMETER_RESTART_APPLICATION

Deprecated. As of 7.0. Only supported for LegacyApplication.

See Also:

Constant Field Values

URL_PARAMETER_CLOSE_APPLICATION

@Deprecated
public static final java.lang.String URL_PARAMETER_CLOSE_APPLICATION

Deprecated. As of 7.0. Only supported for LegacyApplication.

See Also:

Constant Field Values

Constructor Detail

VaadinService

public VaadinService(DeploymentConfiguration deploymentConfiguration)

Creates a new vaadin service based on a deployment configuration

Parameters:

deploymentConfiguration - the deployment configuration for the service

Method Detail

init

public void init()
          throws ServiceException

Initializes this service. The service should be initialized before it is used.

Throws:

ServiceException - if a problem occurs when creating the service

Since:

7.1

createRequestHandlers

protected java.util.List<RequestHandler> createRequestHandlers()
                                                        throws ServiceException

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.

Returns:

The list of request handlers used by this service.

Throws:

ServiceException - if a problem occurs when creating the request handlers

getStaticFileLocation

public abstract java.lang.String getStaticFileLocation(VaadinRequest request)

Return the URL from where static files, e.g. the widgetset and the theme, are served. In a standard configuration the VAADIN folder inside the returned folder is what is used for widgetsets and themes. The returned folder is usually the same as the context path and independent of e.g. the servlet mapping.

Parameters:

request - the request for which the location should be determined

Returns:

The location of static resources (should contain the VAADIN directory). Never ends with a slash (/).

getConfiguredWidgetset

public abstract java.lang.String getConfiguredWidgetset(VaadinRequest request)

Gets the widgetset that is configured for this deployment, e.g. from a parameter in web.xml.

Parameters:

request - the request for which a widgetset is required

Returns:

the name of the widgetset

getConfiguredTheme

public abstract java.lang.String getConfiguredTheme(VaadinRequest request)

Gets the theme that is configured for this deployment, e.g. from a portal parameter or just some sensible default value.

Parameters:

request - the request for which a theme is required

Returns:

the name of the theme

isStandalone

public abstract boolean isStandalone(VaadinRequest request)

Checks whether the UI will be rendered on its own in the browser or whether it will be included into some other context. A standalone UI may do things that might interfere with other parts of a page, e.g. changing the page title and requesting focus upon loading.

Parameters:

request - the request for which the UI is loaded

Returns:

a boolean indicating whether the UI should be standalone

getClassLoader

public java.lang.ClassLoader getClassLoader()

Gets the class loader to use for loading classes loaded by name, e.g. custom UI classes. This is by default the class loader that was used to load the Servlet or Portlet class to which this service belongs.

Returns:

the class loader to use, or null

See Also:

setClassLoader(ClassLoader)

setClassLoader

public void setClassLoader(java.lang.ClassLoader classLoader)

Sets the class loader to use for loading classes loaded by name, e.g. custom UI classes. Invokers of this method should be careful to not break any existing class loader hierarchy, e.g. by ensuring that a class loader set for this service delegates to the previously set class loader if the class is not found.

Parameters:

classLoader - the new class loader to set, not null.

See Also:

getClassLoader()

getMimeType

public abstract java.lang.String getMimeType(java.lang.String resourceName)

Returns the MIME type of the specified file, or null if the MIME type is not known. The MIME type is determined by the configuration of the container, and may be specified in a deployment descriptor. Common MIME types are "text/html" and "image/gif".

Parameters:

resourceName - a String specifying the name of a file

Returns:

a String specifying the file's MIME type

See Also:

ServletContext.getMimeType(String), PortletContext.getMimeType(String)

getDeploymentConfiguration

public DeploymentConfiguration getDeploymentConfiguration()

Gets the deployment configuration.

Returns:

the deployment configuration

setSystemMessagesProvider

public void setSystemMessagesProvider(SystemMessagesProvider systemMessagesProvider)

Sets the system messages provider to use for getting system messages to display to users of this service.

Parameters:

systemMessagesProvider - the system messages provider; null is not allowed.

See Also:

getSystemMessagesProvider()

getSystemMessagesProvider

public SystemMessagesProvider getSystemMessagesProvider()

Gets the system messages provider currently defined for this service.

By default, the DefaultSystemMessagesProvider which always provides the built-in default SystemMessages is used.

Returns:

the system messages provider; not null

See Also:

setSystemMessagesProvider(SystemMessagesProvider), SystemMessagesProvider, SystemMessages

getSystemMessages

public SystemMessages getSystemMessages(java.util.Locale locale,
                                        VaadinRequest request)

Gets the system message to use for a specific locale. This method may also be implemented to use information from current instances of various objects, which means that this method might return different values for the same locale under different circumstances.

Parameters:

locale - the desired locale for the system messages

request -

Returns:

the system messages to use

getBaseDirectory

public abstract java.io.File getBaseDirectory()

Returns the context base directory. Typically an application is deployed in a such way that is has an application directory. For web applications this directory is the root directory of the web applications. In some cases applications might not have an application directory (for example web applications running inside a war).

Returns:

The application base directory or null if the application has no base directory.

addSessionInitListener

public void addSessionInitListener(SessionInitListener listener)

Adds a listener that gets notified when a new Vaadin service session is initialized for this service.

Because of the way different service instances share the same session, the listener is not necessarily notified immediately when the session is created but only when the first request for that session is handled by this service.

Parameters:

listener - the Vaadin service session initialization listener

See Also:

removeSessionInitListener(SessionInitListener), SessionInitListener

removeSessionInitListener

public void removeSessionInitListener(SessionInitListener listener)

Removes a Vaadin service session initialization listener from this service.

Parameters:

listener - the Vaadin service session initialization listener to remove.

See Also:

addSessionInitListener(SessionInitListener)

addSessionDestroyListener

public void addSessionDestroyListener(SessionDestroyListener listener)

Adds a listener that gets notified when a Vaadin service session that has been initialized for this service is destroyed.

The session being destroyed is locked and its UIs have been removed when the listeners are called.

Parameters:

listener - the vaadin service session destroy listener

See Also:

addSessionInitListener(SessionInitListener)

fireSessionDestroy

public void fireSessionDestroy(VaadinSession vaadinSession)

Handles destruction of the given session. Internally ensures proper locking is done.

Parameters:

vaadinSession - The session to destroy

removeSessionDestroyListener

public void removeSessionDestroyListener(SessionDestroyListener listener)

Removes a Vaadin service session destroy listener from this service.

Parameters:

listener - the vaadin service session destroy listener

See Also:

addSessionDestroyListener(SessionDestroyListener)

findVaadinSession

public VaadinSession findVaadinSession(VaadinRequest request)
                                throws ServiceException,
                                       SessionExpiredException

Attempts to find a Vaadin service session associated with this request.

Handles locking of the session internally to avoid creation of duplicate sessions by two threads simultaneously.

Parameters:

request - the request to get a vaadin service session for.

Returns:

the vaadin service session for the request, or null if no session is found and this is a request for which a new session shouldn't be created.

Throws:

ServiceException

SessionExpiredException

See Also:

VaadinSession

getSessionLock

protected java.util.concurrent.locks.Lock getSessionLock(WrappedSession wrappedSession)

Gets the lock instance used to lock the VaadinSession associated with the given wrapped session.

This method uses the wrapped session instead of VaadinSession to be able to lock even before the VaadinSession has been initialized.

Parameters:

wrappedSession - The wrapped session

Returns:

A lock instance used for locking access to the wrapped session

lockSession

protected void lockSession(WrappedSession wrappedSession)

Locks the given session for this service instance. Typically you want to call VaadinSession.lock() instead of this method.

Parameters:

wrappedSession - The session to lock

Throws:

java.lang.IllegalStateException - if the session is invalidated before it can be locked

unlockSession

protected void unlockSession(WrappedSession wrappedSession)

Releases the lock for the given session for this service instance. Typically you want to call VaadinSession.unlock() instead of this method.

Parameters:

wrappedSession - The session to unlock

getApplicationUrl

@Deprecated
protected java.net.URL getApplicationUrl(VaadinRequest request)
                                  throws java.net.MalformedURLException

Deprecated. As of 7.0. Only used to support LegacyApplication.

Get the base URL that should be used for sending requests back to this service.

This is only used to support legacy cases.

Parameters:

request -

Returns:

Throws:

java.net.MalformedURLException

createVaadinSession

protected VaadinSession createVaadinSession(VaadinRequest request)
                                     throws ServiceException

Creates a new Vaadin session for this service and request

Parameters:

request - The request for which to create a VaadinSession

Returns:

A new VaadinSession

Throws:

ServiceException

getExistingSession

protected VaadinSession getExistingSession(VaadinRequest request,
                                           boolean allowSessionCreation)
                                    throws SessionExpiredException

Throws:

SessionExpiredException

requestCanCreateSession

protected abstract boolean requestCanCreateSession(VaadinRequest request)

Checks whether it's valid to create a new service session as a result of the given request.

Parameters:

request - the request

Returns:

true if it's valid to create a new service session for the request; else false

getCurrent

public static VaadinService getCurrent()

Gets the currently used Vaadin service. The current service is automatically defined when processing requests related to the service and in threads started at a point when the current service is defined (see InheritableThreadLocal). In other cases, (e.g. from background threads started in some other way), the current service is not automatically defined.

Returns:

the current Vaadin service instance if available, otherwise null

See Also:

setCurrentInstances(VaadinRequest, VaadinResponse)

setCurrentInstances

public void setCurrentInstances(VaadinRequest request,
                                VaadinResponse response)

Sets the this Vaadin service as the current service and also sets the current Vaadin request and Vaadin response. This method is used by the framework to set the current instances when a request related to the service is processed and they are cleared when the request has been processed.

The application developer can also use this method to define the current instances outside the normal request handling, e.g. when initiating custom background threads.

Parameters:

request - the Vaadin request to set as the current request, or null if no request should be set.

response - the Vaadin response to set as the current response, or null if no response should be set.

See Also:

getCurrent(), getCurrentRequest(), getCurrentResponse()

setCurrent

public static void setCurrent(VaadinService service)

Sets the given Vaadin service as the current service.

Parameters:

service -

getCurrentRequest

public static VaadinRequest getCurrentRequest()

Gets the currently processed Vaadin request. The current request is automatically defined when the request is started. The current request can not be used in e.g. background threads because of the way server implementations reuse request instances.

Returns:

the current Vaadin request instance if available, otherwise null

See Also:

setCurrentInstances(VaadinRequest, VaadinResponse)

getCurrentResponse

public static VaadinResponse getCurrentResponse()

Gets the currently processed Vaadin response. The current response is automatically defined when the request is started. The current response can not be used in e.g. background threads because of the way server implementations reuse response instances.

Returns:

the current Vaadin response instance if available, otherwise null

See Also:

setCurrentInstances(VaadinRequest, VaadinResponse)

getServiceName

public abstract java.lang.String getServiceName()

Gets a unique name for this service. The name should be unique among different services of the same type but the same for corresponding instances running in different JVMs in a cluster. This is typically based on e.g. the configured servlet's or portlet's name.

Returns:

the unique name of this service instance.

findUI

public UI findUI(VaadinRequest request)

Finds the UI that belongs to the provided request. This is generally only supported for UIDL requests as other request types are not related to any particular UI or have the UI information encoded in a non-standard way. The returned UI is also set as the current UI ( UI.setCurrent(UI)).

Parameters:

request - the request for which a UI is desired

Returns:

the UI belonging to the request or null if no UI is found

preserveUIOnRefresh

public boolean preserveUIOnRefresh(UIProvider provider,
                                   UICreateEvent event)

Check if the given UI should be associated with the window.name so that it can be re-used if the browser window is reloaded. This is typically determined by the UI provider which typically checks the @PreserveOnRefresh annotation but UI providers and ultimately VaadinService implementations may choose to override the defaults.

Parameters:

provider - the UI provider responsible for the UI

event - the UI create event with details about the UI

Returns:

true if the UI should be preserved on refresh; false if a new UI instance should be initialized on refreshed.

reinitializeSession

public static void reinitializeSession(VaadinRequest request)

Discards the current session and creates a new session with the same contents. The purpose of this is to introduce a new session key in order to avoid session fixation attacks.

Please note that this method makes certain assumptions about how data is stored in the underlying session and may thus not be compatible with some environments.

Parameters:

request - The Vaadin request for which the session should be reinitialized

getThemeResourceAsStream

public abstract java.io.InputStream getThemeResourceAsStream(UI uI,
                                                             java.lang.String themeName,
                                                             java.lang.String resource)

TODO PUSH Document TODO Pass UI or VaadinSession?

Parameters:

uI -

themeName -

resource -

Returns:

getMainDivId

public abstract java.lang.String getMainDivId(VaadinSession session,
                                              VaadinRequest request,
                                              java.lang.Class<? extends UI> uiClass)

Creates and returns a unique ID for the DIV where the UI is to be rendered.

Parameters:

session - The service session to which the bootstrapped UI will belong.

request - The request for which a div id is needed

uiClass - The class of the UI that will be bootstrapped

Returns:

the id to use in the DOM

closeSession

public void closeSession(VaadinSession session)

Sets the given session to be closed and all its UI state to be discarded at the end of the current request, or at the end of the next request if there is no ongoing one.

After the session has been discarded, any UIs that have been left open will give a Session Expired error and a new session will be created for serving new UIs.

To avoid causing out of sync errors, you should typically redirect to some other page using Page.setLocation(String) to make the browser unload the invalidated UI.

Parameters:

session - the session to close

See Also:

SystemMessages.getSessionExpiredCaption()

requestStart

public void requestStart(VaadinRequest request,
                         VaadinResponse response)

Called before the framework starts handling a request

Parameters:

request - The request

response - The response

requestEnd

public void requestEnd(VaadinRequest request,
                       VaadinResponse response,
                       VaadinSession session)

Called after the framework has handled a request and the response has been written.

Parameters:

request - The request object

response - The response object

session - The session which was used during the request or null if the request did not use a session

getRequestHandlers

public java.lang.Iterable<RequestHandler> getRequestHandlers()

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.

Returns:

a collection of request handlers in the order they are invoked

Since:

7.1

See Also:

createRequestHandlers()

handleRequest

public void handleRequest(VaadinRequest request,
                          VaadinResponse response)
                   throws ServiceException

Handles the incoming request and writes the response into the response object. Uses getRequestHandlers() for handling the request.

If a session expiration is detected during request handling then each request handler has an opportunity to handle the expiration event if it implements SessionExpiredHandler. If no request handler handles session expiration a default expiration message will be written.

Parameters:

request - The incoming request

response - The outgoing response

Throws:

ServiceException - Any exception that occurs during response handling will be wrapped in a ServiceException

writeStringResponse

public void writeStringResponse(VaadinResponse response,
                                java.lang.String contentType,
                                java.lang.String reponseString)
                         throws java.io.IOException

Writes the given string as a response using the given content type.

Parameters:

response - The response reference

contentType - The content type of the response

reponseString - The actual response

Throws:

java.io.IOException - If an error occured while writing the response

handleSessionExpired

protected void handleSessionExpired(VaadinRequest request,
                                    VaadinResponse response)
                             throws ServiceException

Called when the session has expired and the request handling is therefore aborted.

Parameters:

request - The request

response - The response

Throws:

ServiceException - Thrown if there was any problem handling the expiration of the session

createCriticalNotificationJSON

public static java.lang.String createCriticalNotificationJSON(java.lang.String caption,
                                                              java.lang.String message,
                                                              java.lang.String details,
                                                              java.lang.String url)

Creates a JSON message which, when sent to client as-is, will cause a critical error to be shown with the given details.

Parameters:

caption - The caption of the error or null to omit

message - The error message or null to omit

details - Additional error details or null to omit

url - A url to redirect to. If no other details are given then the user will be immediately redirected to this URL. Otherwise the message will be shown and the browser will redirect to the given URL only after the user acknowledges the message. If null then the browser will refresh the current page.

Returns:

A JSON string to be sent to the client

criticalNotification

@Deprecated
public void criticalNotification(VaadinRequest request,
                                            VaadinResponse response,
                                            java.lang.String caption,
                                            java.lang.String message,
                                            java.lang.String details,
                                            java.lang.String url)
                          throws java.io.IOException

Deprecated. As of 7.0. Will likely change or be removed in a future version

Throws:

java.io.IOException

ensurePushAvailable

public boolean ensurePushAvailable()

Enables push if push support is available and push has not yet been enabled. If push support is not available, a warning explaining the situation will be logged at least the first time this method is invoked.

Returns:

true if push can be used; false if push is not available.

isAtmosphereAvailable

protected boolean isAtmosphereAvailable()

Checks whether Atmosphere is avilable for use

Returns:

true if Atmosphere is available, false otherwise

Since:

7.6

verifyNoOtherSessionLocked

public static void verifyNoOtherSessionLocked(VaadinSession session)

Checks that another VaadinSession instance is not locked. This is internally used by VaadinSession.accessSynchronously(Runnable) and UI.accessSynchronously(Runnable) to help avoid causing deadlocks.

Parameters:

session - the session that is being locked

Throws:

java.lang.IllegalStateException - if the current thread holds the lock for another session

Since:

7.1

isOtherSessionLocked

public static boolean isOtherSessionLocked(VaadinSession session)

Checks whether there might be some VaadinSession other than the provided one for which the current thread holds a lock. This method might not detect all cases where some other session is locked, but it should cover the most typical situations.

Parameters:

session - the session that is expected to be locked

Returns:

true if another session is also locked by the current thread; false if no such session was found

Since:

7.2

isCsrfTokenValid

public static boolean isCsrfTokenValid(VaadinSession session,
                                       java.lang.String requestToken)

Verifies that the given CSRF token (aka double submit cookie) is valid for the given session. This is used to protect against Cross Site Request Forgery attacks.

This protection is enabled by default, but it might need to be disabled to allow a certain type of testing. For these cases, the check can be disabled by setting the init parameter disable-xsrf-protection to true.

Parameters:

session - the vaadin session for which the check should be done

requestToken - the CSRF token provided in the request

Returns:

true if the token is valid or if the protection is disabled; false if protection is enabled and the token is invalid

Since:

7.1

See Also:

DeploymentConfiguration.isXsrfProtectionEnabled()

accessSession

public java.util.concurrent.Future<java.lang.Void> accessSession(VaadinSession session,
                                                                 java.lang.Runnable runnable)

Implementation for VaadinSession.access(Runnable). This method is implemented here instead of in VaadinSession to enable overriding the implementation without using a custom subclass of VaadinSession.

Parameters:

session - the vaadin session to access

runnable - the runnable to run with the session locked

Returns:

a future that can be used to check for task completion and to cancel the task

Since:

7.1

See Also:

VaadinSession.access(Runnable)

ensureAccessQueuePurged

public void ensureAccessQueuePurged(VaadinSession session)

Makes sure the pending access queue is purged for the provided session. If the session is currently locked by the current thread or some other thread, the queue will be purged when the session is unlocked. If the lock is not held by any thread, it is acquired and the queue is purged right away.

Parameters:

session - the session for which the access queue should be purged

Since:

7.1.2

runPendingAccessTasks

public void runPendingAccessTasks(VaadinSession session)

Purges the queue of pending access invocations enqueued with VaadinSession.access(Runnable).

This method is automatically run by the framework at appropriate situations and is not intended to be used by application developers.

Parameters:

session - the vaadin session to purge the queue for

Since:

7.1

addServiceDestroyListener

public void addServiceDestroyListener(ServiceDestroyListener listener)

Adds a service destroy listener that gets notified when this service is destroyed.

Parameters:

listener - the service destroy listener to add

Since:

7.2

See Also:

destroy(), removeServiceDestroyListener(ServiceDestroyListener), ServiceDestroyListener

removeServiceDestroyListener

public void removeServiceDestroyListener(ServiceDestroyListener listener)

Removes a service destroy listener that was previously added with addServiceDestroyListener(ServiceDestroyListener).

Parameters:

listener - the service destroy listener to remove

Since:

7.2

destroy

public void destroy()

Called when the servlet, portlet or similar for this service is being destroyed. After this method has been called, no more requests will be handled by this service.

Since:

7.2

See Also:

addServiceDestroyListener(ServiceDestroyListener), Servlet.destroy(), Portlet.destroy()

setDefaultClassLoader

protected void setDefaultClassLoader()

Tries to acquire default class loader and sets it as a class loader for this VaadinService if found. If current security policy disallows acquiring class loader instance it will log a message and re-throw SecurityException

Throws:

java.lang.SecurityException - If current security policy forbids acquiring class loader

Since:

7.3.5

storeSession

protected void storeSession(VaadinSession session,
                            WrappedSession wrappedSession)

Called when the VaadinSession should be stored.

By default stores the VaadinSession in the underlying HTTP session.

Parameters:

session - the VaadinSession to store

wrappedSession - the underlying HTTP session

Since:

7.6

writeToHttpSession

protected void writeToHttpSession(WrappedSession wrappedSession,
                                  VaadinSession session)

Performs the actual write of the VaadinSession to the underlying HTTP session after sanity checks have been performed.

Called by storeSession(VaadinSession, WrappedSession)

Parameters:

wrappedSession - the underlying HTTP session

session - the VaadinSession to store

Since:

7.6

loadSession

protected VaadinSession loadSession(WrappedSession wrappedSession)

Called when the VaadinSession should be loaded from the underlying HTTP session

Parameters:

wrappedSession - the underlying HTTP session

Returns:

the VaadinSession in the HTTP session or null if not found

Since:

7.6

readFromHttpSession

protected VaadinSession readFromHttpSession(WrappedSession wrappedSession)

Performs the actual read of the VaadinSession from the underlying HTTP session after sanity checks have been performed.

Called by loadSession(WrappedSession).

Parameters:

wrappedSession - the underlying HTTP session

Returns:

the VaadinSession or null if no session was found

Since:

7.6

removeSession

public void removeSession(WrappedSession wrappedSession)

Called when the VaadinSession should be removed from the underlying HTTP session

Parameters:

wrappedSession - the underlying HTTP session

Since:

7.6

removeFromHttpSession

protected void removeFromHttpSession(WrappedSession wrappedSession)

Performs the actual removal of the VaadinSession from the underlying HTTP session after sanity checks have been performed

Parameters:

wrappedSession - the underlying HTTP session

Since:

7.6

getSessionAttributeName

protected java.lang.String getSessionAttributeName()

Returns the name used for storing the VaadinSession in the underlying HTTP session

Returns:

the attribute name used for storing the VaadinSession

Since:

7.6