Class UIInitHandler

Field Detail

• BROWSER_DETAILS_PARAMETER

  public static final String BROWSER_DETAILS_PARAMETER

  See Also:

  Constant Field Values

Constructor Detail

• UIInitHandler

  public UIInitHandler()

Method Detail

• isInitRequest

  protected abstract boolean isInitRequest​(VaadinRequest request)

• canHandleRequest

  protected boolean canHandleRequest​(VaadinRequest request)

  Description copied from class: SynchronizedRequestHandler

  Check whether a request may be handled by this handler. This can be used as an optimization to avoid locking the session just to investigate some method property. The default implementation just returns true which means that all requests will be handled by calling SynchronizedRequestHandler.synchronizedHandleRequest(VaadinSession, VaadinRequest, VaadinResponse) with the session locked.

  Overrides:

  canHandleRequest in class SynchronizedRequestHandler

  Parameters:

  request - the request to handle

  Returns:

  true if the request handling should continue once the session has been locked; false if there's no need to lock the session since the request would still not be handled.

• synchronizedHandleRequest

  public boolean synchronizedHandleRequest​(VaadinSession session,
                                           VaadinRequest request,
                                           VaadinResponse response)
                                    throws IOException

  Description copied from class: SynchronizedRequestHandler

  Identical to SynchronizedRequestHandler.handleRequest(VaadinSession, VaadinRequest, VaadinResponse) except the VaadinSession is locked before this is called and unlocked after this has completed.

  Specified by:

  synchronizedHandleRequest in class SynchronizedRequestHandler

  Parameters:

  session - The session for the request

  request - The request to handle

  response - The response object to which a response can be written.

  Returns:

  true if a response has been written and no further request handlers should be called, otherwise false

  Throws:

  IOException - If an IO error occurred

  See Also:

  SynchronizedRequestHandler.handleRequest(VaadinSession, VaadinRequest, VaadinResponse)

• getEmbedId

  protected String getEmbedId​(VaadinRequest request)

  Constructs an embed id based on information in the request.

  Parameters:

  request - the request to get embed information from

  Returns:

  the embed id, or null if id is not available.

  Since:

  7.2

  See Also:

  UI.getEmbedId()

• getInitialUidl

  protected String getInitialUidl​(VaadinRequest request,
                                  UI uI)
                           throws IOException

  Generates the initial UIDL message that can e.g. be included in a html page to avoid a separate round trip just for getting the UIDL.

  Parameters:

  request - the request that caused the initialization

  uI - the UI for which the UIDL should be generated

  Returns:

  a string with the initial UIDL message

  Throws:

  IOException