unsupported Java version "16", defaulting to 1.7

[AndyObtiva]

I have been getting these errors ever since I upgraded to JDK 16, and I am not sure if the source is ruby-maven, so I am reporting and cross-referencing this issue with the one I reported at the psych project.

ruby/psych#520

• MacOS Big Sur 11.2.3 x64
• Processor 2.5 GHz Quad-Core Intel Core i7 x64
• rvm 1.29.12-next
• java version "16.0.2" 2021-07-20 Java(TM) SE Runtime Environment (build 16.0.2+7-67) Java HotSpot(TM) 64-Bit Server VM (build 16.0.2+7-67, mixed mode, sharing)
• gem version 3.2.27 (after running gem update --system)
• jruby 9.2.19.0 (2.5.8) 2021-06-15 55810c552b Java HotSpot(TM) 64-Bit Server VM 16.0.2+7-67 on 16.0.2+7-67 +jit [darwin-x86_64]
• OR jruby 9.3.0.0 (2.6.8) 2021-09-17 85c20e780f Java HotSpot(TM) 64-Bit Server VM 16.0.2+7-67 on 16.0.2+7-67 +jit [darwin-x86_64]

When running gem install psych -v4.0.1:

% gem install psych -v4.0.1 
Fetching psych-4.0.1-java.gem
  jar dependencies for psych-4.0.1-java.gemspec . . .
unsupported Java version "16", defaulting to 1.7
[ERROR] Internal error: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d96250 -> [Help 1]
org.apache.maven.InternalErrorException: Internal error: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d96250
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:121)
	at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
	at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d96250
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/InternalErrorException
ERROR:  While executing gem ... (Errno::ENOENT)
    No such file or directory - /Users/andymaleh/.rvm/gems/jruby-9.2.19.0@snowboard_utah/gems/psych-4.0.1-java/deps.lst

When running lock_jars:

lock_jars --vendor-dir vendor/jars
Installing gem 'ruby-maven' . . .
Installing gem 'ruby-maven-libs' . . .

using maven for the first time results in maven
downloading all its default plugin and can take time.
as those plugins get cached on disk and further execution
of maven is much faster then the first time.


-- jar root dependencies --

[DEPRECATED] `Bundler.with_clean_env` has been deprecated in favor of `Bundler.with_unbundled_env`. If you instead want the environment before bundler was originally loaded, use `Bundler.with_original_env` (called at /Users/andymaleh/.rvm/gems/jruby-9.3.0.0@snowboard_utah/gems/ruby-maven-3.3.12/lib/ruby_maven.rb:38)
unsupported Java version "16", defaulting to 1.7
[ERROR] Internal error: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d96250 -> [Help 1]
org.apache.maven.InternalErrorException: Internal error: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d96250
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:121)
	at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
	at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d96250
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/InternalErrorException

[AndyObtiva]

Just noting that the situation didn't seem to improve with newer psych v4.0.2 and jruby-9.3.1.0:

Fetching psych-4.0.2-java.gem
  jar dependencies for psych-4.0.2-java.gemspec . . .
Installing gem 'ruby-maven' . . .
Fetching ruby-maven-3.3.12.gem
Fetching ruby-maven-libs-3.3.9.gem
Successfully installed ruby-maven-libs-3.3.9
Successfully installed ruby-maven-3.3.12

using maven for the first time results in maven
downloading all its default plugin and can take time.
as those plugins get cached on disk and further execution
of maven is much faster then the first time.

unsupported Java version "16", defaulting to 1.7
[ERROR] Internal error: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d1ff6b1 -> [Help 1]
org.apache.maven.InternalErrorException: Internal error: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d1ff6b1
	at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:121)
	at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
	at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
	at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:567)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
	at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
	at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
	at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.jruby.exceptions.RaiseException: (LoadError) library `java' could not be loaded: java.lang.reflect.InaccessibleObjectException: Unable to make protected native java.lang.Object java.lang.Object.clone() throws java.lang.CloneNotSupportedException accessible: module java.base does not "opens java.lang" to unnamed module @4d1ff6b1
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/InternalErrorException
ERROR:  While executing gem ... (Errno::ENOENT)
    No such file or directory - /Users/andymaleh/.rvm/gems/jruby-9.3.1.0@glimmer-dsl-swt/gems/psych-4.0.2-java/deps.lst

[deivid-rodriguez]

This should get fixed by #2. In particular by the first commit there, the rest of the PR is just me trying stuff to get the CI green. Can you try it?

[AndyObtiva]

Thank you for mentioning. I just tried it and I confirm that #2 makes the error go away when installing psych (gem install psych -v4.0.1) or locking jars (lock_jars).

p.s. I continue to see this warning (seems harmless):

2021-10-25T15:50:17.772-04:00 [main] WARN FilenoUtil : Native subprocess control requires open access to sun.nio.ch
Pass '--add-opens java.base/sun.nio.ch=org.jruby.dist' or '=org.jruby.core' to enable.
      org.yaml:snakeyaml:1.28:compile

[deivid-rodriguez]

I'm glad to hear that :)

[deivid-rodriguez]

Closed by #2! :)

[headius]

Marking as fixed. Release will take some work as the other parts of the Ruby/Maven stack also need updates.