Logout시 에러로그가나옵니다.

[hangum]

로그아웃은 정상으로 되지만 에러로그가 올라갑니다.

2016-08-22 18:01:55.735:WARN:/:UIThread [22a5d71f]: Received InterruptedException while terminating UIThread
java.lang.InterruptedException
at java.lang.Object.wait(Native Method)
at java.lang.Thread.join(Thread.java:1281)
at java.lang.Thread.join(Thread.java:1355)
at org.eclipse.rap.rwt.internal.lifecycle.UIThread.terminateThread(UIThread.java:125)
at org.eclipse.rap.rwt.internal.lifecycle.UIThread.interceptShutdown(UIThread.java:160)
at org.eclipse.rap.rwt.internal.service.UISessionImpl.valueUnbound(UISessionImpl.java:286)
at org.eclipse.equinox.http.servlet.internal.servlet.HttpSessionAdaptor$HttpSessionAttributeWrapper.valueUnbound(HttpSessionAdaptor.java:126)
at org.eclipse.jetty.server.session.AbstractSession.unbindValue(AbstractSession.java:607)
at org.eclipse.jetty.server.session.AbstractSession.callSessionAttributeListeners(AbstractSession.java:532)
at org.eclipse.jetty.server.session.AbstractSession.changeAttribute(AbstractSession.java:513)
at org.eclipse.jetty.server.session.AbstractSession.setAttribute(AbstractSession.java:461)
at org.eclipse.jetty.server.session.AbstractSession.removeAttribute(AbstractSession.java:384)
at org.eclipse.equinox.http.servlet.internal.servlet.HttpSessionAdaptor.removeAttribute(HttpSessionAdaptor.java:240)
at org.eclipse.equinox.http.servlet.internal.servlet.HttpSessionAdaptor.invalidate(HttpSessionAdaptor.java:224)
at org.eclipse.rap.rwt.osgi.internal.HttpSessionWrapper.invalidate(HttpSessionWrapper.java:113)
at com.hangum.tadpole.engine.utils.HttpSessionCollectorUtil.sessionDestroyed(HttpSessionCollectorUtil.java:88)
at com.hangum.tadpole.rdb.core.actions.global.ExitAction.beforeLogoutAction(ExitAction.java:107)
at com.hangum.tadpole.rdb.core.actions.global.ExitAction.serverLogout(ExitAction.java:93)
at com.hangum.tadpole.rdb.core.actions.global.ExitAction.run(ExitAction.java:80)
at org.eclipse.jface.action.Action.runWithEvent(Action.java:493)
at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:575)
at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:492)
at org.eclipse.jface.action.ActionContributionItem$6.handleEvent(ActionContributionItem.java:443)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:109)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:687)
at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:594)
at org.eclipse.swt.widgets.Display.executeNextEvent(Display.java:1212)
at org.eclipse.swt.widgets.Display.runPendingMessages(Display.java:1193)
at org.eclipse.swt.widgets.Display.safeReadAndDispatch(Display.java:1176)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:1168)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2733)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2694)
at org.eclipse.ui.internal.Workbench.access$5(Workbench.java:2530)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:701)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:336)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:684)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:157)
at com.hangum.tadpole.application.Application.createUI(Application.java:48)
at org.eclipse.rap.rwt.internal.lifecycle.RWTLifeCycle.createUI(RWTLifeCycle.java:177)
at org.eclipse.rap.rwt.internal.lifecycle.RWTLifeCycle$UIThreadController.run(RWTLifeCycle.java:290)
at java.lang.Thread.run(Thread.java:745)
at org.eclipse.rap.rwt.internal.lifecycle.UIThread.run(UIThread.java:107)
2016-08-22 18:01:55.825:WARN:oejs.ServletHandler:qtp1960459096-53: ERROR: /;jsessionid=18093crmt73p4wggyviab1cee
java.lang.NullPointerException: The parameter 'uiSession' must not be null.
at org.eclipse.rap.rwt.internal.util.ParamCheck.notNull(ParamCheck.java:29)
at org.eclipse.rap.rwt.SingletonUtil.getUniqueInstance(SingletonUtil.java:73)
at org.eclipse.rap.rwt.SingletonUtil.getSessionInstance(SingletonUtil.java:58)
at org.eclipse.rap.rwt.internal.serverpush.ServerPushManager.getInstance(ServerPushManager.java:54)
at org.eclipse.rap.rwt.internal.serverpush.ServerPushServiceHandler.service(ServerPushServiceHandler.java:31)
at org.eclipse.rap.rwt.engine.RWTServlet.handleValidRequest(RWTServlet.java:135)
at org.eclipse.rap.rwt.engine.RWTServlet.handleRequest(RWTServlet.java:117)
at org.eclipse.rap.rwt.engine.RWTServlet.doGet(RWTServlet.java:100)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.eclipse.rap.rwt.osgi.internal.CutOffContextPathWrapper.service(CutOffContextPathWrapper.java:106)
at org.eclipse.equinox.http.servlet.internal.HttpServiceRuntimeImpl$LegacyServlet.service(HttpServiceRuntimeImpl.java:1271)
at org.eclipse.equinox.http.servlet.internal.registration.EndpointRegistration.service(EndpointRegistration.java:162)
at org.eclipse.equinox.http.servlet.internal.servlet.ResponseStateHandler.processRequest(ResponseStateHandler.java:63)
at org.eclipse.equinox.http.servlet.internal.HttpServiceRuntimeImpl.doDispatch(HttpServiceRuntimeImpl.java:413)
at org.eclipse.equinox.http.servlet.internal.HttpServiceRuntimeImpl.doDispatch(HttpServiceRuntimeImpl.java:341)
at org.eclipse.equinox.http.servlet.internal.HttpServiceRuntimeImpl.doDispatch(HttpServiceRuntimeImpl.java:204)
at org.eclipse.equinox.http.servlet.internal.servlet.ProxyServlet.processAlias(ProxyServlet.java:91)
at org.eclipse.equinox.http.servlet.internal.servlet.ProxyServlet.service(ProxyServlet.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
at org.eclipse.equinox.http.jetty.internal.HttpServerManager$InternalHttpServiceServlet.service(HttpServerManager.java:379)
at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:808)
at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:587)
at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:221)
at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
at org.eclipse.jetty.server.Server.handle(Server.java:497)
at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:310)
at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:540)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:635)
at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:555)
at java.lang.Thread.run(Thread.java:745)