Travis failure because of Spotbugs

[leventov]

[ERROR] Unread field: org.apache.druid.indexing.worker.config.WorkerConfig.intermediaryPartitionCleanupPeriodSec; should this field be static? [org.apache.druid.indexing.worker.config.WorkerConfig] At WorkerConfig.java:[line 49] SS_SHOULD_BE_STATIC
[ERROR] Unread field: org.apache.druid.indexing.worker.config.WorkerConfig.intermediaryPartitionDiscoveryPeriodSec; should this field be static? [org.apache.druid.indexing.worker.config.WorkerConfig] At WorkerConfig.java:[line 46] SS_SHOULD_BE_STATIC
[ERROR] Unread field: org.apache.druid.indexing.worker.config.WorkerConfig.version; should this field be static? [org.apache.druid.indexing.worker.config.WorkerConfig] At WorkerConfig.java:[line 38] SS_SHOULD_BE_STATIC
[INFO] 

Probably caused by #8073.

FYI @Fokko

[Fokko]

Thanks for letting me know. I can fix this in a hour, I'm currently traveling. Feel free to revert the commit as well. I can open a new PR.

[Fokko]

Here we go #8138

[clintropolis]

Since #8138 seems to be failing with the same issue, I think we should consider reverting #8073 and then maybe could repurpose #8138 to trying to enable this again so we can unblock CI.

[jon-wei]

@clintropolis Reverting #8073 sounds good

[jihoonson]

Raised #8143. Tested it locally.

[clintropolis]

Raised #8143. Tested it locally.

In that case we can skip reverting #8073 I think

[jihoonson]

Sorry, there was some mistakes I think. #8143 doesn't work. +1 for reverting #8073.

[asdf2014]

Perhaps adding @SuppressFBWarnings(value = "SS_SHOULD_BE_STATIC") annotations to WorkerConfig can solve this problem. After opening a new spotbugs check in the future, we should rebase the latest master branch and ensure that CI can pass.

[asdf2014]

@Fokko In #8138, the @SuppressWarnings annotation used will not work and should be replaced with @SuppressFBWarnings.

[asdf2014]

Despite our best efforts, the FSF has never considered the Apache License to be compatible with GPL version 2, ...

Oops.. Using @SuppressFBWarnings from com.google.code.findbugs:annotations or com.github.spotbugs:spotbugs-annotations will result in a license conflict issue, even if the latter has LGPL 2.1 license. More details: https://www.apache.org/licenses/GPL-compatibility.html