Re: Question about tomcat startup ConcurrentModificationException
Hello Jilles So I have downloaded the mx4j-2.1.1.tar and untarred it, but since there is no exact match for jmx.jar in the mx4j distribution I zipinfo'd and sorted: the original tomcat/bin/jmx.tar (235 classes) mx4j.jar (285 classes) When diff'd, mostly a good match, but a couple of classes that are in jmx.jar are missing from mx4j.jar. I presume these are classes req'd by others in the package but are not called directly by tomcat. So you are suggesting that I replace the tomcat/bin/jmx.jar with the mx4j.jar ? If so, then I have a stupid question: when I do this replacement, should I rename the mx4j.jar to jmx.jar ? Maurice Jilles van Gurp wrote: The fix is to replace the mx4j jar file in the release (bin/jmx.jar) with the fixed version (latest 2.1.x) which has been available for a long time now from the mx4j project site. You might also search this mailinglist. This must be one of the more frequently raised topics. I know I found the right answer here half a year ago or so. I'd really appreciate a stable 5.0.x release with the fix. I've known about this bug for more than half a year now and I still encounter it at least once a week at customers. I then need to explain that it is not our product that is broken but tomcat and that it's a well known issue and it is easy to fix. Basically all our customers run into this issue. Lets face it, 5.0.28 is basically broken because of this easy to fix bug. People claim it rarely occurs (and consequently that it is perfectly acceptable to occasionally fail to launch with an obscure exception). Yet, I can't launch my webapp on an unpatched tomcat 5.0.28 unless I fix this first. Sometimes I forget on a clean install and then seconds later slap my forward. Just do a 5.0.28_01 with the fixed jar or finally move 5.0.30 to a stable release (I can't convince customers to install beta software) but please fix it one way or the other. Jilles Tim Funk wrote: Search bugzilla. There is a bug report about ConcurrentModificationException - it has to do with mx4j having a race condition. The bug describes a fix. -Tim Maurice Yarrow wrote: Hello Tomcat people When tomcat is restarted, it occasionally (1 in 25 times) gets the below exception. (tomcat 5.0.28, on Fedora Core 1) What is the significance of this? Thanks Maurice INFO: Starting Coyote HTTP/1.1 on http-8080 Sep 26, 2005 9:29:19 AM org.apache.coyote.http11.Http11Protocol start INFO: Starting Coyote HTTP/1.1 on http-8443 Sep 26, 2005 9:29:19 AM org.apache.coyote.tomcat5.MapperListener init WARNING: Error registering contexts java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:782) at java.util.HashMap$EntryIterator.next(HashMap.java:824) at java.util.HashMap.putAllForCreate(HashMap.java:424) at java.util.HashMap.clone(HashMap.java:656) at mx4j.server.DefaultMBeanRepository.clone(DefaultMBeanRepository.java:56) at mx4j.server.MBeanServerImpl.findMBeansByPattern(MBeanServerImpl.java:160 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Question about tomcat startup ConcurrentModificationException
The fix is to replace the mx4j jar file in the release (bin/jmx.jar) with the fixed version (latest 2.1.x) which has been available for a long time now from the mx4j project site. You might also search this mailinglist. This must be one of the more frequently raised topics. I know I found the right answer here half a year ago or so. I'd really appreciate a stable 5.0.x release with the fix. I've known about this bug for more than half a year now and I still encounter it at least once a week at customers. I then need to explain that it is not our product that is broken but tomcat and that it's a well known issue and it is easy to fix. Basically all our customers run into this issue. Lets face it, 5.0.28 is basically broken because of this easy to fix bug. People claim it rarely occurs (and consequently that it is perfectly acceptable to occasionally fail to launch with an obscure exception). Yet, I can't launch my webapp on an unpatched tomcat 5.0.28 unless I fix this first. Sometimes I forget on a clean install and then seconds later slap my forward. Just do a 5.0.28_01 with the fixed jar or finally move 5.0.30 to a stable release (I can't convince customers to install beta software) but please fix it one way or the other. Jilles Tim Funk wrote: Search bugzilla. There is a bug report about ConcurrentModificationException - it has to do with mx4j having a race condition. The bug describes a fix. -Tim Maurice Yarrow wrote: Hello Tomcat people When tomcat is restarted, it occasionally (1 in 25 times) gets the below exception. (tomcat 5.0.28, on Fedora Core 1) What is the significance of this? Thanks Maurice INFO: Starting Coyote HTTP/1.1 on http-8080 Sep 26, 2005 9:29:19 AM org.apache.coyote.http11.Http11Protocol start INFO: Starting Coyote HTTP/1.1 on http-8443 Sep 26, 2005 9:29:19 AM org.apache.coyote.tomcat5.MapperListener init WARNING: Error registering contexts java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:782) at java.util.HashMap$EntryIterator.next(HashMap.java:824) at java.util.HashMap.putAllForCreate(HashMap.java:424) at java.util.HashMap.clone(HashMap.java:656) at mx4j.server.DefaultMBeanRepository.clone(DefaultMBeanRepository.java:56) at mx4j.server.MBeanServerImpl.findMBeansByPattern(MBeanServerImpl.java:160 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Question about tomcat startup ConcurrentModificationException
Hello Tomcat people When tomcat is restarted, it occasionally (1 in 25 times) gets the below exception. (tomcat 5.0.28, on Fedora Core 1) What is the significance of this? Thanks Maurice INFO: Starting Coyote HTTP/1.1 on http-8080 Sep 26, 2005 9:29:19 AM org.apache.coyote.http11.Http11Protocol start INFO: Starting Coyote HTTP/1.1 on http-8443 Sep 26, 2005 9:29:19 AM org.apache.coyote.tomcat5.MapperListener init WARNING: Error registering contexts java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:782) at java.util.HashMap$EntryIterator.next(HashMap.java:824) at java.util.HashMap.putAllForCreate(HashMap.java:424) at java.util.HashMap.clone(HashMap.java:656) at mx4j.server.DefaultMBeanRepository.clone(DefaultMBeanRepository.java:56) at mx4j.server.MBeanServerImpl.findMBeansByPattern(MBeanServerImpl.java:1603) at mx4j.server.MBeanServerImpl.queryObjectNames(MBeanServerImpl.java:1568) at mx4j.server.MBeanServerImpl.queryMBeans(MBeanServerImpl.java:1512) at org.apache.coyote.tomcat5.MapperListener.init(MapperListener.java:115) at org.apache.coyote.tomcat5.CoyoteConnector.start(CoyoteConnector.java:1537) at org.apache.catalina.core.StandardService.start(StandardService.java:489) at org.apache.catalina.core.StandardServer.start(StandardServer.java:2313) at org.apache.catalina.startup.Catalina.start(Catalina.java:556) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:324) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:287) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:425) - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Question about tomcat startup ConcurrentModificationException
Search bugzilla. There is a bug report about ConcurrentModificationException - it has to do with mx4j having a race condition. The bug describes a fix. -Tim Maurice Yarrow wrote: Hello Tomcat people When tomcat is restarted, it occasionally (1 in 25 times) gets the below exception. (tomcat 5.0.28, on Fedora Core 1) What is the significance of this? Thanks Maurice INFO: Starting Coyote HTTP/1.1 on http-8080 Sep 26, 2005 9:29:19 AM org.apache.coyote.http11.Http11Protocol start INFO: Starting Coyote HTTP/1.1 on http-8443 Sep 26, 2005 9:29:19 AM org.apache.coyote.tomcat5.MapperListener init WARNING: Error registering contexts java.util.ConcurrentModificationException at java.util.HashMap$HashIterator.nextEntry(HashMap.java:782) at java.util.HashMap$EntryIterator.next(HashMap.java:824) at java.util.HashMap.putAllForCreate(HashMap.java:424) at java.util.HashMap.clone(HashMap.java:656) at mx4j.server.DefaultMBeanRepository.clone(DefaultMBeanRepository.java:56) at mx4j.server.MBeanServerImpl.findMBeansByPattern(MBeanServerImpl.java:160 - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
