Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Ralph, are you going to work on this issue? On Mon, Oct 17, 2016 at 2:04 PM, Mikael Ståldal wrote: > So this issue is triggered by the fact that the Kafka client library we > use itself does logging via SLF4J during initialization. And in this > particular web

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

So this issue is triggered by the fact that the Kafka client library we use itself does logging via SLF4J during initialization. And in this particular web configuration, org.slf4j.LoggerFactory.getLogger(Class) return null during Configuration.start(). On Sat, Aug 20, 2016 at 12:13 AM, Bill

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Ralph, thanks! created jira: https://issues.apache.org/jira/browse/LOG4J2-1535 I guess I still wanted the ClassLoaderContextSelector, as I wanted each webapp to have it's own config (log to different target etc), but just shared same jars. so the intention is to have all log related jars in

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

So they are being kicked off by the webapp initialization. That follows what I was thinking. I have a suspicion I may have to put in some code to check if the logging classes are in the same ClassLoader as the current ClassLoader. If they aren’t we probably need to kick off logging

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Never mind. I was looking in the wrong place. They are there. Ralph > On Aug 19, 2016, at 2:04 PM, Ralph Goers wrote: > > I didn’t get an attachment. I believe the mailing list manager strips > attachments. > > Ralph > >> On Aug 19, 2016, at 1:52 PM, Bill Okara

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

I didn’t get an attachment. I believe the mailing list manager strips attachments. Ralph > On Aug 19, 2016, at 1:52 PM, Bill Okara wrote: > > Hi Gary, > > actually the full stack was attached in that email already, please let > me know if you can't find them... >

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

sorry Ralph, the last reply was for you (didn't read the sender carefully) On Fri, Aug 19, 2016 at 2:52 PM, Bill Okara wrote: > Hi Gary, > > actually the full stack was attached in that email already, please let > me know if you can't find them... > (Attachments:

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Hi Gary, actually the full stack was attached in that email already, please let me know if you can't find them... (Attachments: stacktrace_webinf.txt (5 kb) stacktrace_tomcatlib.txt (7 kb) ) Yeah, that's kinda my understanding (or guess) too. That is, by putting the log related jars in

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

I have a suspicion the key part of the stack trace isn’t included. I am guessing that the code that causes the first call to the Kafka appender is in your web app. This causes the ClassLoaderContextSelector to initialize Log4j for the web app ClassLoader. Kafka itself is in tomcat/lib. When

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

thanks for guiding me through this, Gary! Attached are 2 stack dumps, one is with the log related jars packaged in WEB-INF/lib, the other is having the jars provided in tomcat/lib, and below are what I noticed; that is, in WEB-INF/lib case, when initializing the private static final Logger log =

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

On Fri, Aug 19, 2016 at 8:56 AM, Bill Okara wrote: > Hi Gary, > > it turned out that the first NullPointerException is caused by the > same reason, that is, in: > > private KafkaProducer(ProducerConfig config, Serializer > keySerializer, Serializer valueSerializer) { >

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Hi Gary, it turned out that the first NullPointerException is caused by the same reason, that is, in: private KafkaProducer(ProducerConfig config, Serializer keySerializer, Serializer valueSerializer) { try { log.trace("Starting the Kafka producer"); the log in

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Hello Bill, What you could do is start the whole thing in a debugger and put a breakpoint in org.apache.kafka.clients.producer.KafkaProducer.KafkaProducer(ProducerConfig, Serializer, Serializer) here: } catch (Throwable t) { // call close methods if internal objects are

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Thanks, Gary, you're probably right, the log in log.info seems to be the culprit. By doing the 'trace' in log4j2.xml, it seems that the initialization for the WebappClassLoader actually finished OK, but when initializing for the Parent Classloader, it's when the NullPointerException happened.

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Based on the stack trace, it looks like the Slf4j logger in KafkaProducer is null: log.info("Closing the Kafka producer with timeoutMillis = {} ms.", timeUnit.toMillis(timeout)); It does not look like timeUnit can be null, so it must be log. The root problem of course if that we have an

Re: Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

tried again, seemed like the .out extension got filtered out by mail server... On Thu, Aug 18, 2016 at 4:41 PM, Bill Okara wrote: > attach the catalina.out again, didn't seem to go through last time... > > > On Thu, Aug 18, 2016 at 4:33 PM, Bill Okara

Log4j2 Kafka appender NullPointerException when put the related jars in tomcat lib

Hi, When trying out the log4j2 Kafka appender, it works ok if all the log4j2/kafka-client related jars are packaged in the webapp's WEB-INF/lib, like: >ls WEB-INF/lib/ jackson-core-2.8.1.jar log4j-core-2.6.2.jar lz4-1.3.0.jar kafka-clients-0.10.0.1.jar log4j-slf4j-impl-2.6.2.jar