下午好，谢谢您的关注，接下来会发生什么，我已经安装了我的系统。关于日志的异常是：
[2019-02-21T11:07:19.411-0300] [glassfish 4.1] [INFO] [] [javax.enterprise.web.core] [tid: _ThreadID=712 _ThreadName=RunLevelControllerThread-1550758037259] [timeMillis: 1550758039411] [levelValue: 800] [[
Session event listener threw exception
java.lang.NullPointerException
at org.jboss.weld.servlet.WeldTerminalListener.getSessionContext(WeldTerminalListener.java:72)
at org.jboss.weld.servlet.WeldTerminalListener.sessionDestroyed(WeldTerminalListener.java:64)
at org.apache.catalina.session.StandardSession.expire(StandardSession.java:910)
at org.apache.catalina.session.StandardSession.expire(StandardSession.java:854)
at org.apache.catalina.session.StandardSession.expire(StandardSession.java:842)
at org.apache.catalina.session.StandardManager.stop(StandardManager.java:955)
at org.apache.catalina.core.StandardContext.stop(StandardContext.java:6164)
at com.sun.enterprise.web.WebModule.stop(WebModule.java:720)
at org.apache.catalina.core.ContainerBase.removeChild(ContainerBase.java:1172)
at com.sun.enterprise.web.WebContainer.unloadWebModule(WebContainer.java:2439)
at com.sun.enterprise.web.WebContainer.unloadWebModule(WebContainer.java:2394)
at com.sun.enterprise.web.WebApplication.stop(WebApplication.java:190)
at org.glassfish.internal.data.EngineRef.stop(EngineRef.java:161)
at org.glassfish.internal.data.ModuleInfo.stop(ModuleInfo.java:324)
at org.glassfish.internal.data.ApplicationInfo.stop(ApplicationInfo.java:380)
at com.sun.enterprise.v3.server.ApplicationLifecycle.unload(ApplicationLifecycle.java:1059)
at com.sun.enterprise.v3.server.ApplicationLifecycle.disable(ApplicationLifecycle.java:2128)
at com.sun.enterprise.v3.server.ApplicationLifecycle.disable(ApplicationLifecycle.java:113)
at com.sun.enterprise.v3.server.ApplicationLoaderService.stopApplication(ApplicationLoaderService.java:496)
at com.sun.enterprise.v3.server.ApplicationLoaderService.preDestroy(ApplicationLoaderService.java:464)
at org.jvnet.hk2.internal.ClazzCreator.preDestroyMe(ClazzCreator.java:339)
at org.jvnet.hk2.internal.ClazzCreator.dispose(ClazzCreator.java:404)
at org.jvnet.hk2.internal.SystemDescriptor.dispose(SystemDescriptor.java:526)
at org.glassfish.hk2.runlevel.internal.AsyncRunLevelContext.destroyOne(AsyncRunLevelContext.java:328)
at org.glassfish.hk2.runlevel.RunLevelContext.destroyOne(RunLevelContext.java:101)
at org.jvnet.hk2.internal.ServiceHandleImpl.destroy(ServiceHandleImpl.java:183)
at org.glassfish.hk2.runlevel.internal.CurrentTaskFuture$DownQueueRunner.run(CurrentTaskFuture.java:1270)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
]]
有人知道这是什么原因吗？我正在使用Java 7，JSF，GlassFish 4.1，Ubuntu服务器和mysql，有什么建议吗？