Javadoc warnings not displayed

[Jesse Glick]

I have long been confused by why our CI system, which runs one or another AdoptOpenJDK build (for example the Docker image `maven`), prints warnings from Javadoc—which are then displayed in various forms—while my local builds show nothing. After a lot of comparisons I picked https://github.com/jenkinsci/copyartifact-plugin @2913845ea143095d32e5773c7af713b20d2c6906 and ran `mvn -V clean javadoc:jar` using openjdk-8-jdk-headless 8u265-b01-0ubuntu2~20.04, which prints no warnings, whereas if I set `$JAVA_HOME` to https://github.com/AdoptOpenJDK/openjdk8-binaries/releases/download/jdk8u265-b01/OpenJDK8U-jdk_x64_linux_hotspot_8u265b01.tar.gz the same command prints eight warnings as expected. I finally downloaded openjdk-8_8u265-b01-0ubuntu2_20.04.debian.tar.xz and found `debian/patches/disable-doclint-by-default.diff` which links to http://blog.joda.org/2014/02/turning-off-doclint-in-jdk-8-javadoc.html and https://lists.fedoraproject.org/pipermail/java-devel/2014-February/005150.html for justification in turning off doclint, the latter of which even admits that

> This is really an issue that should be fixed in the upstream packages, and disabling javadocs is just masking the problem. So given that, how about we disable doclint for a year and give upstreams time to fix it?

This patch is apparently years old, and any Java project would surely have long since either fixed its Javadoc errors (not necessarily warnings!) or configured its build tool to pass the option to suppress this stuff. The Debian package should certainly not modify the default behavior of a very well known tool.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Thorsten Glaser (mirabilos)]

We’ll not do this change to openjdk-8 now, as that potentially breaks other peoples’ builds.

I think openjdk-21 is the current LTS version, with which people can test their javadocs, or just re-enable doclint per command line.