Thanks Jason. So what is the temporary workaround for this until its fixed? For now, we just restart the app server having this issue, but we keep seeing this issue time and again.
-----Original Message----- From: Jason Gustafson [mailto:ja...@confluent.io] Sent: Thursday, September 24, 2015 12:21 PM To: users@kafka.apache.org Subject: Re: ZkClient throwing NPEs Hey Hema, I'm not too familiar with ZkClient, but I took a look at the code and it seems like there may still be a race condition around reconnects which could cause the NPE you're seeing. I left a comment on the github issue on the slim chance I'm not wrong: https://github.com/sgroschupf/zkclient/issues/25. -Jason On Thu, Sep 24, 2015 at 10:09 AM, Hema Bhatia <hema.bha...@apollo.edu> wrote: > Can anyone help with the below issue... > Thanks. > > -----Original Message----- > From: Hema Bhatia [mailto:hema.bha...@apollo.edu] > Sent: Tuesday, September 22, 2015 12:57 PM > To: users@kafka.apache.org > Subject: ZkClient throwing NPEs > > Hi, > > I keep getting the below exception when Kafka tries to connect to > zookeeper and zookeeper is momentarily not able to connect. After > that, connection does not restore unless we restart the servers. > > This may be connected to this issue : > https://issues.apache.org/jira/browse/KAFKA-824 But I am already using > zkclient-0.5, and still seeing this issue. > > > java.lang.NullPointerException: null > > at > org.I0Itec.zkclient.ZkConnection.exists(ZkConnection.java:107) > ~[zkclient-0.5.jar:0.5] > > at > org.I0Itec.zkclient.ZkClient$3.call(ZkClient.java:631) > ~[zkclient-0.5.jar:0.5] > > at > org.I0Itec.zkclient.ZkClient$3.call(ZkClient.java:628) > ~[zkclient-0.5.jar:0.5] > > at > org.I0Itec.zkclient.ZkClient.retryUntilConnected(ZkClient.java:883) > ~[zkclient-0.5.jar:0.5] > > at > org.I0Itec.zkclient.ZkClient.exists(ZkClient.java:628) > ~[zkclient-0.5.jar:0.5] > > at > org.I0Itec.zkclient.ZkClient.exists(ZkClient.java:637) > ~[zkclient-0.5.jar:0.5] > > at > kafka.admin.AdminUtils$.topicExists(AdminUtils.scala:163) > ~[kafka_2.10-0.8.2.0.jar:na] > > at > kafka.admin.AdminUtils.topicExists(AdminUtils.scala) > ~[kafka_2.10-0.8.2.0.jar:na] > > Any ideas of how to solve this issue? > > Thanks, > Hema > >
