Recently I try to upgrade our system to Vaadin 7, now I am using beta 11, but time to time, the below exception come out: And restart the browser (even in a private mode, the issue still same) and even use another pc, it won’t help. All further request to the server will prompt me this exception.
I need to restart the server and clean the browser, it disappeared, but later (don’t know how long) it comes out again. Anyone experience the same thing? If it is one time thing, it is not very big problem, but if this issue happen, the whole server is always return this error until restart, which is not correct.
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type Exception report
message java.lang.RuntimeException: A connector with id 2 is already registered!
description The server encountered an internal error that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: java.lang.RuntimeException: A connector with id 2 is already registered!
com.vaadin.server.VaadinServlet.handleServiceException(VaadinServlet.java:580)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:343)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:201)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
root cause
java.lang.RuntimeException: A connector with id 2 is already registered!
com.vaadin.ui.ConnectorTracker.registerConnector(ConnectorTracker.java:127)
com.vaadin.server.AbstractClientConnector.attach(AbstractClientConnector.java:599)
com.vaadin.ui.AbstractComponent.attach(AbstractComponent.java:554)
com.vaadin.server.AbstractClientConnector.attach(AbstractClientConnector.java:604)
com.vaadin.ui.AbstractComponent.attach(AbstractComponent.java:554)
com.vaadin.server.AbstractClientConnector.setParent(AbstractClientConnector.java:586)
com.vaadin.ui.AbstractComponent.setParent(AbstractComponent.java:457)
com.vaadin.ui.AbstractSingleComponentContainer.setContent(AbstractSingleComponentContainer.java:138)
com.vaadin.ui.UI.setContent(UI.java:1039)
bm.validusre.vcaps2.vaadin.ui.PropertyDFQuickQuoteUI.createUi(PropertyDFQuickQuoteUI.java:51)
bm.validusre.vcaps2.vaadin.ui.PropertyDFQuickQuoteUI.init(PropertyDFQuickQuoteUI.java:30)
com.vaadin.ui.UI.doInit(UI.java:523)
com.vaadin.server.AbstractCommunicationManager.getBrowserDetailsUI(AbstractCommunicationManager.java:2448)
com.vaadin.server.AbstractCommunicationManager.handleBrowserDetailsRequest(AbstractCommunicationManager.java:2343)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:325)
com.vaadin.server.VaadinServlet.service(VaadinServlet.java:201)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
note The full stack trace of the root cause is available in the Apache Tomcat/7.0.32 logs.
Answer myself.
I use spring to manage vaadin, so in some cases, the vaadin component in spring configuration is use default (which is singleton mode), this cause different session use the same instance of vaadin component, which cause issue. When all things configured to prototype, looks fine so far, but still need to keep more monitoring.
Yes I am using the Spring Integration Add On too, which made me make all components @Session(“prototype”) scope, otherwise indeed you have singleton vaadin components, which will be used by all UI instances; usually you don’t want that.
But had actually one vaadin component that needs to be Singleton(ish) scope, and that caused also the “A connection with id 7 is already registered!” problem, mainly when logging out and logging in again. Had to change the scope for that singleton component to @Scope(request) to get it fixed.
Made a
summary of the investigation regarding this scope stuff + how to properly log out, hope it helps somebody…