Package com.vaadin.client.communication

Interface ConnectionStateHandler

  • All Known Implementing Classes:
    DefaultConnectionStateHandler
    public interface ConnectionStateHandler
    Handles problems and other events which occur during communication with the server. The handler is responsible for handling any problem in XHR, heartbeat and push connections in a way it sees fit. The default implementation is DefaultConnectionStateHandler.
    Since:
    1.0
    Author:
    Vaadin Ltd

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static String UIDL_REFRESH_TOKEN
      A string that, if found in a non-JSON response to a UIDL request, will cause the browser to refresh the page.

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void configurationUpdated()
      Called when some part of the reconnect dialog configuration has been changed.
      void heartbeatException​(com.google.gwt.xhr.client.XMLHttpRequest request, Exception exception)
      Called when an exception occurs during a Heartbeat request.
      void heartbeatInvalidStatusCode​(com.google.gwt.xhr.client.XMLHttpRequest xhr)
      Called when a heartbeat request returns a status code other than OK (200).
      void heartbeatOk()
      Called when a Heartbeat request succeeds.
      void pushClientTimeout​(PushConnection pushConnection, com.google.gwt.core.client.JavaScriptObject response)
      Called when a client side timeout occurs before a push connection to the server completes.
      void pushClosed​(PushConnection pushConnection, com.google.gwt.core.client.JavaScriptObject responseObject)
      Called when the push connection to the server is closed.
      void pushError​(PushConnection pushConnection, com.google.gwt.core.client.JavaScriptObject response)
      Called when a fatal error fatal error occurs in the push connection.
      void pushInvalidContent​(PushConnection pushConnection, String message)
      Called when invalid content (not JSON) was pushed from the server through the push connection.
      void pushNotConnected​(elemental.json.JsonObject payload)
      Called when a message is to be sent to the server through the push channel but the push channel is not connected.
      void pushOk​(PushConnection pushConnection)
      Called when the push connection to the server has been established.
      void pushReconnectPending​(PushConnection pushConnection)
      Called when the push connection has lost the connection to the server and will proceed to try to re-establish the connection.
      void pushScriptLoadError​(String resourceUrl)
      Called when the required push script could not be loaded.
      void xhrException​(XhrConnectionError xhrConnectionError)
      Called when an exception occurs during an XmlHttpRequest request to the server.
      void xhrInvalidContent​(XhrConnectionError xhrConnectionError)
      Called when invalid content (not JSON) was returned from the server as the result of an XmlHttpRequest request.
      void xhrInvalidStatusCode​(XhrConnectionError xhrConnectionError)
      Called when invalid status code (not 200) was returned by the server as the result of an XmlHttpRequest.
      void xhrOk()
      Called whenever a XmlHttpRequest to the server completes successfully.

    • Field Detail

      • UIDL_REFRESH_TOKEN

        static final String UIDL_REFRESH_TOKEN
        A string that, if found in a non-JSON response to a UIDL request, will cause the browser to refresh the page. If followed by a colon, optional whitespace, and a URI, causes the browser to synchronously load the URI.

        This allows, for instance, a servlet filter to redirect the application to a custom login page when the session expires. For example: 

         if (sessionExpired) {
     response.setHeader("Content-Type", "text/html");
     response.getWriter().write(myLoginPageHtml + "<!-- Vaadin-Refresh: "
             + request.getContextPath() + " -->");
 }
        See Also:
        Constant Field Values

    • Method Detail

      • heartbeatException

        void heartbeatException​(com.google.gwt.xhr.client.XMLHttpRequest request,
                        Exception exception)
        Called when an exception occurs during a Heartbeat request.
        Parameters:
        request - The heartbeat request
        exception - The exception which occurred

      • heartbeatInvalidStatusCode

        void heartbeatInvalidStatusCode​(com.google.gwt.xhr.client.XMLHttpRequest xhr)
        Called when a heartbeat request returns a status code other than OK (200).
        Parameters:
        xhr - the heartbeat request

      • heartbeatOk

        void heartbeatOk()
        Called when a Heartbeat request succeeds.

      • pushClosed

        void pushClosed​(PushConnection pushConnection,
                com.google.gwt.core.client.JavaScriptObject responseObject)
        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"),
        Parameters:
        pushConnection - The push connection which was closed
        responseObject - An object containing response data

      • pushClientTimeout

        void pushClientTimeout​(PushConnection pushConnection,
                       com.google.gwt.core.client.JavaScriptObject response)
        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,
        Parameters:
        pushConnection - The push connection which timed out
        response - An object containing response data

      • pushError

        void pushError​(PushConnection pushConnection,
               com.google.gwt.core.client.JavaScriptObject response)
        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.
        Parameters:
        pushConnection - The push connection where the error occurred
        response - An object containing response data

      • pushReconnectPending

        void pushReconnectPending​(PushConnection pushConnection)
        Called when the push connection has lost the connection to the server and will proceed to try to re-establish the connection.
        Parameters:
        pushConnection - The push connection which will be reconnected

      • pushOk

        void pushOk​(PushConnection pushConnection)
        Called when the push connection to the server has been established.
        Parameters:
        pushConnection - The push connection which was established

      • pushScriptLoadError

        void pushScriptLoadError​(String resourceUrl)
        Called when the required push script could not be loaded.
        Parameters:
        resourceUrl - The URL which was used for loading the script

      • xhrException

        void xhrException​(XhrConnectionError xhrConnectionError)
        Called when an exception occurs during an XmlHttpRequest request to the server.
        Parameters:
        xhrConnectionError - An event containing what was being sent to the server and what exception occurred

      • xhrInvalidContent

        void xhrInvalidContent​(XhrConnectionError xhrConnectionError)
        Called when invalid content (not JSON) was returned from the server as the result of an XmlHttpRequest request.
        Parameters:
        xhrConnectionError - An event containing what was being sent to the server and what was returned

      • xhrInvalidStatusCode

        void xhrInvalidStatusCode​(XhrConnectionError xhrConnectionError)
        Called when invalid status code (not 200) was returned by the server as the result of an XmlHttpRequest.
        Parameters:
        xhrConnectionError - An event containing what was being sent to the server and what was returned

      • xhrOk

        void xhrOk()
        Called whenever a XmlHttpRequest to the server completes successfully.

      • pushNotConnected

        void pushNotConnected​(elemental.json.JsonObject payload)
        Called when a message is to be sent to the server through the push channel but the push channel is not connected.
        Parameters:
        payload - The payload to send to the server

      • pushInvalidContent

        void pushInvalidContent​(PushConnection pushConnection,
                        String message)
        Called when invalid content (not JSON) was pushed from the server through the push connection.
        Parameters:
        pushConnection - the push connection which was used
        message - the received message

      • configurationUpdated

        void configurationUpdated()
        Called when some part of the reconnect dialog configuration has been changed.