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Derek Baum commented on FELIX-5302: ----------------------------------- Hi Carsten, This appears to have fixed the problem. I've tried 10 times and I can no longer reproduce it. It used to occur about every other time. Thanks, -- Derek > NPE using Http Whiteboard > ------------------------- > > Key: FELIX-5302 > URL: https://issues.apache.org/jira/browse/FELIX-5302 > Project: Felix > Issue Type: Bug > Components: HTTP Service > Affects Versions: http.jetty-3.2.0 > Reporter: Derek Baum > Assignee: Carsten Ziegeler > Fix For: http.jetty-3.2.2 > > Attachments: http.jetty.bad.log, http.jetty.good.log > > > I am getting this NPE about 50% of the time after reconfiguring my servlet > (causing it to unregister and re-register): > [org.apache.felix.http.jetty:3.2.0] Exception while processing request to > /hello/sayHello > java.lang.NullPointerException: null > org.apache.felix.http.base.internal.handler.ServletHandler.handle(ServletHandler.java:85) > org.apache.felix.http.base.internal.dispatch.InvocationChain.doFilter(InvocationChain.java:79) > org.apache.felix.http.base.internal.dispatch.Dispatcher.dispatch(Dispatcher.java:124) > org.apache.felix.http.base.internal.DispatcherServlet.service(DispatcherServlet.java:61) > javax.servlet.http.HttpServlet.service(HttpServlet.java:725) > org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:845) > org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583) > org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:224) > org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1160) > org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:511) > org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185) > org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1092) > org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141) > org.eclipse.jetty.server.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:213) > org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134) > org.eclipse.jetty.server.Server.handle(Server.java:518) > org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:308) > org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:244) > org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273) > org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95) > org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93) > org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceAndRun(ExecuteProduceConsume.java:246) > org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:156) > org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:654) > org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:572) > java.lang.Thread.run(Thread.java:745) > The servlet uses the Http Whiteboard: > @Component( > property = { > HttpWhiteboardConstants.HTTP_WHITEBOARD_SERVLET_PATTERN + "=/hello/sayHello", > HttpWhiteboardConstants.HTTP_WHITEBOARD_RESOURCE_PATTERN + > "=/hello/static/*", > HttpWhiteboardConstants.HTTP_WHITEBOARD_RESOURCE_PREFIX + "=/static"}) > public class HelloWorldServlet extends HttpServlet implements Servlet { > } > About 50% of the time when I initially deploy the Servlet, I've noticed that > ServletRegistry.addServlet() is called twice for the same servlet with the > same serviceId. > I don't know why this happens, but when it does it leads to the NPE above. > The second addServlet() invokes addToInactiveList(). > The system works in this state, but it has a duplicate servlet handler in the > inactive list. > If the servlet is now reconfigured, causing it to unregister and re-register, > we get the NPE above on the next request. > This appears to be because ServletRegistry.removeServlet() fails to invoke > "resolvers.remove(regHandler)", when the inactive list contains the argument > ServletInfo. > Alternatively, addServlet() should never allow a duplicate registration to be > added to the inactive list. -- This message was sent by Atlassian JIRA (v6.3.4#6332)