doc-jar fails on OpenJDK 9+

[adamretter]

The error is:

[INFO] --- scala-maven-plugin:4.3.0:doc-jar (scala-doc-jar) @ csv-validator-core ---
java.lang.reflect.InvocationTargetException
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:564)
	at scala_maven_executions.MainHelper.runMain(MainHelper.java:161)
	at scala_maven_executions.MainWithArgsInFile.main(MainWithArgsInFile.java:26)
Caused by: java.lang.NoClassDefFoundError: javax/tools/ToolProvider
	at scala.reflect.io.JavaToolsPlatformArchive.iterator(ZipArchive.scala:301)
	at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
	at scala.reflect.io.AbstractFile.foreach(AbstractFile.scala:92)
	at scala.tools.nsc.util.DirectoryClassPath.traverse(ClassPath.scala:277)
	at scala.tools.nsc.util.DirectoryClassPath.x$15$lzycompute(ClassPath.scala:299)
	at scala.tools.nsc.util.DirectoryClassPath.x$15(ClassPath.scala:299)
	at scala.tools.nsc.util.DirectoryClassPath.packages$lzycompute(ClassPath.scala:299)
	at scala.tools.nsc.util.DirectoryClassPath.packages(ClassPath.scala:299)
	at scala.tools.nsc.util.DirectoryClassPath.packages(ClassPath.scala:264)
	at scala.tools.nsc.util.MergedClassPath$$anonfun$packages$1.apply(ClassPath.scala:358)
	at scala.tools.nsc.util.MergedClassPath$$anonfun$packages$1.apply(ClassPath.scala:358)
	at scala.collection.Iterator$class.foreach(Iterator.scala:891)
	at scala.collection.AbstractIterator.foreach(Iterator.scala:1334)
	at scala.collection.IterableLike$class.foreach(IterableLike.scala:72)
	at scala.collection.AbstractIterable.foreach(Iterable.scala:54)
	at scala.tools.nsc.util.MergedClassPath.packages$lzycompute(ClassPath.scala:358)
	at scala.tools.nsc.util.MergedClassPath.packages(ClassPath.scala:353)
	at scala.tools.nsc.symtab.SymbolLoaders$PackageLoader$$anonfun$doComplete$1.apply$mcV$sp(SymbolLoaders.scala:269)

Adding the option-nobootcp to the args for doc-jar seems to be a viable workaround, i.e.:

                      <execution>
                        <id>scala-doc-jar</id>
                        <phase>package</phase>
                        <goals>
                            <goal>doc-jar</goal>
                        </goals>
                        <configuration>
                            <args>
                                <arg>-nobootcp</arg>
                            </args>
                        </configuration>
                    </execution>

[slandelle]

Can't reproduce, please provide a simple sample project to reproduce (not your full multi-module project with tons of plugins).

[adamretter]

@slandelle is the output from Travis CI with logs, which shows JDK 1.8 passing, but JDK 9, 10, and 11 failing with that error helpful? You can see it here - https://travis-ci.org/digital-preservation/csv-validator/builds/623143738

[slandelle]

As I said, your project is way too complicated and involves lots of plugins to be able to investigate in isolation.
Run mvn package scala:doc-jar against https://github.com/davidB/scala-maven-plugin/tree/master/samples/prj_multi_modules with Java 11 and you'll see the javadoc jars are properly generated.

[asmotrich]

@slandelle I see exactly the same failure with the same stack trace using scala-maven-plugin 4.3.0 with the prj_multi_modules but using Scala 2.11.12 and Java 11. Scala 2.12.X works fine though.

[SethTisue]

using Scala 2.11.12 and Java 11. Scala 2.12.X works fine though

I think this is an upstream problem in Scala 2.11 (and presumably 2.10 as well), rather than a Maven problem per se: scala/bug#10603

that ticket also recommends adding -nobootcp to the Scala compiler flags, as Adam recommends above

[asmotrich]

The -nobootcp flag did not help with Scala 2.11 on Java 11.

[SethTisue]

The -nobootcp flag did not help with Scala 2.11 on Java 11.

Can you provide a simple sample project that demonstrates this?

[asmotrich]

@SethTisue you can take your sample project samples/prj_multi_modules and just change the Scala version to 2.11.12. I tried with and without -nobootcp, no difference. But as you mentioned before, this is probably Scala 2.11 issue.

[slandelle]

Generally speaking, it seems scala-compiler 2.11 doesn't work properly with Java 11.

Switching to 2.11.11 here and running mvn package with Java 11 crashes:

error: scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
	at scala.reflect.internal.MissingRequirementError$.signal(MissingRequirementError.scala:17)
	at scala.reflect.internal.MissingRequirementError$.notFound(MissingRequirementError.scala:18)
	at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:53)
	at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:45)
	at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:45)
	at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:66)
	at scala.reflect.internal.Mirrors$RootsBase.getClassByName(Mirrors.scala:102)
	at scala.reflect.internal.Mirrors$RootsBase.getRequiredClass(Mirrors.scala:105)
	at scala.reflect.internal.Definitions$DefinitionsClass.ObjectClass$lzycompute(Definitions.scala:257)
	at scala.reflect.internal.Definitions$DefinitionsClass.ObjectClass(Definitions.scala:257)
	at scala.reflect.internal.Definitions$DefinitionsClass.init(Definitions.scala:1390)
	at scala.tools.nsc.Global$Run.<init>(Global.scala:1242)
	at scala.tools.nsc.Driver.doCompile(Driver.scala:31)
	at scala.tools.nsc.MainClass.doCompile(Main.scala:23)
	at scala.tools.nsc.Driver.process(Driver.scala:51)
	at scala.tools.nsc.Main.process(Main.scala)

Anyway, I'm closing this issue as that's really not something that can be fixed here, it could only be fixed in .

Now, let's be realistic:

• Scala 2.11.11 was released on 13-Apr-2017
• Java 11 reached GA on 25-Sept-2018

We can safely say Scala 2.11 has reached end-of-life and Java 11 support is very unlikely to happen. And IMHO, it shouldn't.

Libraries are dropping Scala 2.11 support as well:

• http4s
• circe
• cats

Your Scala version has been dead for 2.5 years, time to upgrade, people!

[SethTisue]

I think Stephane is right to close the ticket, but we can still discuss workarounds.

Stephane writes:

Generally speaking, it seems scala-compiler 2.11 doesn't work properly with Java 11.

My working hypothesis is that it can be always be made to work by passing -nobootcp, as per scala/bug#10603

Switching to 2.11.11 here and running mvn package with Java 11 crashes:

True, but adding -nobootcp fixes it: SethTisue@217d282

@asmotrich writes:

you can take your sample project samples/prj_multi_modules and just change the Scala version to 2.11.12. I tried with and without -nobootcp, no difference

that wasn't my experience. when I tried it, SethTisue@217d282 fixes both mvn package and mvn package scala:doc-jar

you say it doesn't work for you in your project. perhaps you are doing something differently?

[slandelle]

you say it doesn't work for you in your project. perhaps you are doing something differently?

On my side, it didn't work but I configured at execution level instead of root one, which might have been wrong (I never remember how this works...).

[asmotrich]

Exactly the same in my case: I put configuration at the execution level and it did not work, once I followed recommendations in SethTisue@217d282 <SethTisue@217d282> and put it at the root level everything worked correctly. This is perfectly functional workaround, end of story IMHO. I figured a way to move my environment forward to Scala 2.12 and everything seems to be in good order. Thanks!

…

On Tue, Dec 17, 2019 at 7:21 AM Stephane Landelle ***@***.***> wrote: you say it doesn't work for you in your project. perhaps you are doing something differently? On my side, it didn't work but I configured at execution level instead of root one, which might have been wrong (I never remember how this works...). — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#376?email_source=notifications&email_token=AFMMEQBFEQX5LQZF6OBCCNLQZDVBJA5CNFSM4JY5T3ZKYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEHCXEPQ#issuecomment-566587966>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AFMMEQBATZPXLHGN4MU3MZDQZDVBJANCNFSM4JY5T3ZA> .