Package com.vaadin.client.communication

Class DefaultConnectionStateHandler

  • All Implemented Interfaces:
    ConnectionStateHandler
    public class DefaultConnectionStateHandler
extends Object
implements ConnectionStateHandler
    Default implementation of the connection state handler.

    Handles temporary errors by showing a reconnect dialog to the user while trying to re-establish the connection to the server and re-send the pending message.

    Handles permanent errors by showing a critical system notification to the user

    Since:
    7.6
    Author:
    Vaadin Ltd

    • Constructor Detail

      • DefaultConnectionStateHandler

        public DefaultConnectionStateHandler()

    • Method Detail

      • getConnection

        protected ApplicationConnection getConnection()
        Returns the connection this handler is connected to
        Returns:
        the connection for this handler

      • xhrException

        public void xhrException​(XhrConnectionError xhrConnectionError)
        Description copied from interface: ConnectionStateHandler
        Called when an exception occurs during an XmlHttpRequest request to the server.
        Specified by:
        xhrException in interface ConnectionStateHandler
        Parameters:
        xhrConnectionError - An event containing what was being sent to the server and what exception occurred

      • heartbeatInvalidStatusCode

        public void heartbeatInvalidStatusCode​(com.google.gwt.http.client.Request request,
                                       com.google.gwt.http.client.Response response)
        Description copied from interface: ConnectionStateHandler
        Called when a heartbeat request returns a status code other than OK (200)
        Specified by:
        heartbeatInvalidStatusCode in interface ConnectionStateHandler
        Parameters:
        request - The heartbeat request
        response - The heartbeat response

      • handleRecoverableError

        protected void handleRecoverableError​(DefaultConnectionStateHandler.Type type,
                                      JsonObject payload)
        Called whenever an error occurs in communication which should be handled by showing the reconnect dialog and retrying communication until successful again
        Parameters:
        type - The type of failure detected
        payload - The message which did not reach the server, or null if no message was involved (heartbeat or push connection failed)

      • scheduleReconnect

        protected void scheduleReconnect​(JsonObject payload)
        Called after a problem occurred. This method is responsible for re-sending the payload to the server (if not null) or re-send a heartbeat request at some point
        Parameters:
        payload - the payload that did not reach the server, null if the problem was detected by a heartbeat

      • doReconnect

        protected void doReconnect​(JsonObject payload)
        Re-sends the payload to the server (if not null) or re-sends a heartbeat request immediately
        Parameters:
        payload - the payload that did not reach the server, null if the problem was detected by a heartbeat

      • updateDialog

        protected void updateDialog()
        Called whenever a reconnect attempt fails to allow updating of dialog contents

      • giveUp

        protected void giveUp()
        Called when we should give up trying to reconnect and let the user decide how to continue

      • isDialogVisible

        protected boolean isDialogVisible()
        Checks if the reconnect dialog is visible to the user
        Returns:
        true if the user can see the dialog, false otherwise

      • showDialog

        protected void showDialog()
        Called when the reconnect dialog should be shown. This is typically when N seconds has passed since a problem with the connection has been detected

      • hideDialog

        protected void hideDialog()
        Called when the reconnect dialog should be hidden.

      • getDialogTextGaveUp

        protected String getDialogTextGaveUp​(int reconnectAttempt)
        Gets the text to show in the reconnect dialog after giving up (reconnect limit reached)
        Parameters:
        reconnectAttempt - The number of the current reconnection attempt
        Returns:
        The text to show in the reconnect dialog after giving up

      • getDialogText

        protected String getDialogText​(int reconnectAttempt)
        Gets the text to show in the reconnect dialog
        Parameters:
        reconnectAttempt - The number of the current reconnection attempt
        Returns:
        The text to show in the reconnect dialog

      • handleUnauthorized

        protected void handleUnauthorized​(XhrConnectionError xhrConnectionError)

      • pushOk

        public void pushOk​(PushConnection pushConnection)
        Description copied from interface: ConnectionStateHandler
        Called when the push connection to the server has been established.
        Specified by:
        pushOk in interface ConnectionStateHandler
        Parameters:
        pushConnection - The push connection which was established

      • pushNotConnected

        public void pushNotConnected​(JsonObject payload)
        Description copied from interface: ConnectionStateHandler
        Called when a message is to be sent to the server through the push channel but the push channel is not connected
        Specified by:
        pushNotConnected in interface ConnectionStateHandler
        Parameters:
        payload - The payload to send to the server

      • pushReconnectPending

        public void pushReconnectPending​(PushConnection pushConnection)
        Description copied from interface: ConnectionStateHandler
        Called when the push connection has lost the connection to the server and will proceed to try to re-establish the connection
        Specified by:
        pushReconnectPending in interface ConnectionStateHandler
        Parameters:
        pushConnection - The push connection which will be reconnected

      • pushError

        public void pushError​(PushConnection pushConnection,
                      com.google.gwt.core.client.JavaScriptObject response)
        Description copied from interface: ConnectionStateHandler
        Called when a fatal error fatal error occurs in the push connection. The push connection will not try to recover from this situation itself and typically the problem handler should not try to do automatic recovery either. The cause can be e.g. maximum number of reconnection attempts have been reached, neither the selected transport nor the fallback transport can be used or similar.
        Specified by:
        pushError in interface ConnectionStateHandler
        Parameters:
        pushConnection - The push connection where the error occurred
        response - An object containing response data

      • pushClientTimeout

        public void pushClientTimeout​(PushConnection pushConnection,
                              com.google.gwt.core.client.JavaScriptObject response)
        Description copied from interface: ConnectionStateHandler
        Called when a client side timeout occurs before a push connection to the server completes. The client side timeout causes a disconnection of the push connection and no reconnect will be attempted after this method is called,
        Specified by:
        pushClientTimeout in interface ConnectionStateHandler
        Parameters:
        pushConnection - The push connection which timed out
        response - An object containing response data

      • pushClosed

        public void pushClosed​(PushConnection pushConnection,
                       com.google.gwt.core.client.JavaScriptObject response)
        Description copied from interface: ConnectionStateHandler
        Called when the push connection to the server is closed. This might result in the push connection trying a fallback connection method, trying to reconnect to the server or might just be an indication that the connection was intentionally closed ("unsubscribe"),
        Specified by:
        pushClosed in interface ConnectionStateHandler
        Parameters:
        pushConnection - The push connection which was closed