[SUREFIRE-1459] mvn+java7 and POM with toolchains targeting java8 fail in surefire plugin

[jira-importer]

Rüdiger Groß-Hardt opened SUREFIRE-1459 and commented

We compile and test with a POM using a toolchain configuration targeting JDK 8. Maven itself runs with JDK 7. If we run tests with the maven-surefire-plugin and forkCount=1 and reuseForks=false the build fails with
java.lang.UnsupportedClassVersionError: SomeTestClass : Unsupported major.minor version 52.0
If we set reuseForks=true, it builds fine. Other combinations seem to fail, if the plugin code running in the JDK 7 context presumably needs to use reflections to enumerate test classes.

As newbies to toolchains, we were assuming, that toolchains enabled us to effectively decouple the JDK version used to run maven from the JDK version used to run the tests.

This problem took us quite some time to solve. As an improvement I would suggest a meaningful warning or error message stating that the surefire plugin must be run with a JDK version higher than or equal to the version of the target JDK from the toolchain configuration.

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Affects: 2.20.1

Attachments:

• run-with-errors.txt (97.31 kB)
• surefire-1459.zip (19.69 kB)

1 votes, 4 watchers

[jira-importer]

Tibor Digana commented

Rüdiger Groß-Hardt
This is quite expected with forkCount=1 and reuseForks=false, because the tests must be filtered in-plugin JVM which is Java 7 in your case. Try to set reuseForks=true which should avoid the issue.
The best would be to make filtering in forked JVM but not sure if doable.

[jira-importer]

Rüdiger Groß-Hardt commented

Using reuseForks=true doesn't cut it for the project in question. We will probably simply use JDK 8 to run maven as well, though that might be a problem with older projects, which do not use toolchains and might have a problem, when build with JDK 8. But I am sure we will find a working solution.

My main concern is really, that a warning or error should inform the user of the fact, that the surefire plugin needs a JDK version which is higher or equal than the version the target JDK. So other users don't fall in the same trap we did.

[jira-importer]

Tibor Digana commented

Can you attach a log file?

Thx

[jira-importer]

Rüdiger Groß-Hardt commented

I have attached a minimal project for reproducing the problem. To use it you need to set the path to JDK 7 and JDK 8 in run.cmd and toolchains.xml. A logfile with the result of a failed run is also attached. Sorry, it tooks so long..

[jira-importer]

Tibor Digana commented

This happens only if you are filtering some test classes via test/includes/excludes.
Nowadays it is impossible for us to fix it because this fix requires some changes in Provider API. We have it in plan, pls see our road map.

[jira-importer]

Markus Kopp commented

This also affects java8 configured in path and java11 configured with toolchain plugin and on Linux.

[liamsharp]

Having the same issue today running with JAVA_HOME as Java 21 and compiling for Java 25. forkCount 1 and reuseForks false are is the only way to get it to work, all other options fail (I'd like to reuse forks with a fork count of 2). @Tibor17 I followed the link to the roadmap but that seems to just show the help page for the plugin - does anyone have an updated link to the road map or is there another way around this issue now?