Bug 51910

Summary:	NPE in comet processing when shutting down Tomcat
Product:	Tomcat 7	Reporter:	Konstantin Kolinko <knst.kolinko>
Component:	Catalina	Assignee:	Tomcat Developers Mailing List <dev>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	P2
Version:	trunk
Target Milestone:	---
Hardware:	PC
OS:	Windows XP

Description Konstantin Kolinko 2011-09-28 12:05:19 UTC

I've hit it when testing 7.0.22 RC.

1. Configure Tomcat with NIO connector
2. Start Tomcat and open Comet chat example
http://localhost:8080/examples/jsp/chat/index.jsp
3. Type some Nickname and press button to start chat
The chat log will be in the second frame at the lower half of the page.
4. While chat log is active (Browser shows page as being loaded),
shut down Tomcat.
5. Observe NPE in the logs:

28.09.2011 15:55:32 org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["http-nio-8080"]
28.09.2011 15:55:33 org.apache.catalina.connector.CoyoteAdapter event
SEVERE: null
java.lang.NullPointerException
        at org.apache.catalina.core.StandardWrapperValve.event(StandardWrapperValve.java:354)
        at org.apache.catalina.core.StandardContextValve.event(StandardContextValve.java:192)
        at org.apache.catalina.valves.ValveBase.event(ValveBase.java:226)
        at org.apache.catalina.core.StandardHostValve.event(StandardHostValve.java:245)
        at org.apache.catalina.valves.ValveBase.event(ValveBase.java:226)
        at org.apache.catalina.valves.ValveBase.event(ValveBase.java:226)
        at org.apache.catalina.core.StandardEngineValve.event(StandardEngineValve.java:138)
        at org.apache.catalina.connector.CoyoteAdapter.event(CoyoteAdapter.java:211)
        at org.apache.coyote.http11.Http11NioProcessor.event(Http11NioProcessor.java:131)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.>
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1554)
        at org.apache.tomcat.util.net.NioEndpoint.processSocket(NioEndpoint.java:717)
        at org.apache.tomcat.util.net.NioEndpoint$Poller.cancelledKey(NioEndpoint.java:1026)
        at org.apache.tomcat.util.net.NioEndpoint$Poller.processKey(NioEndpoint.java:1169)
        at org.apache.tomcat.util.net.NioEndpoint$Poller.timeout(NioEndpoint.java:1352)
        at org.apache.tomcat.util.net.NioEndpoint$Poller.run(NioEndpoint.java:1085)
        at java.lang.Thread.run(Thread.java:662)
28.09.2011 15:55:33 org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["ajp-bio-8009"]

Comment 1 Konstantin Kolinko 2011-09-28 14:32:54 UTC

It is reproducible with APR connector as well.

===================
INFO: Stopping ProtocolHandler ["http-apr-8080"]
28.09.2011 18:31:25 org.apache.catalina.connector.CoyoteAdapter event
SEVERE: null
java.lang.NullPointerException
	at org.apache.catalina.core.StandardWrapperValve.event(StandardWrapperValve.java:354)
	at org.apache.catalina.core.StandardContextValve.event(StandardContextValve.java:192)
	at org.apache.catalina.valves.ValveBase.event(ValveBase.java:226)
	at org.apache.catalina.core.StandardHostValve.event(StandardHostValve.java:245)
	at org.apache.catalina.valves.ValveBase.event(ValveBase.java:226)
	at org.apache.catalina.valves.ValveBase.event(ValveBase.java:226)
	at org.apache.catalina.core.StandardEngineValve.event(StandardEngineValve.java:138)
	at org.apache.catalina.connector.CoyoteAdapter.event(CoyoteAdapter.java:211)
	at org.apache.coyote.http11.Http11AprProcessor.event(Http11AprProcessor.java:133)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:513)
	at org.apache.tomcat.util.net.AprEndpoint$SocketEventProcessor.run(AprEndpoint.java:1869)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:662)
28.09.2011 18:31:25 org.apache.coyote.AbstractProtocol stop
INFO: Stopping ProtocolHandler ["ajp-apr-8009"]
===================

Comment 2 Mark Thomas 2011-10-01 14:13:39 UTC

Fixed in trunk and 7.0.x and will be included in 7.0.23 onwards.