Running test of file compiled with Maven / Java 11 produces java.lang.UnsupportedClassVersionError

[ryno1234]

I haven't seen anyone else post this issue so I'm wondering if I have a configuration problem.

I have compiled my multi-module Maven project targeting Java 11. While within VS Code, attempts to run a test file's test produces the following error:

java.lang.UnsupportedClassVersionError: com/myapp/service/MyServiceImplTest has been compiled by a more recent version of the Java Runtime (class file version 55.0), this version of the Java Runtime only recognizes class file versions up to 52.0
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
	at java.net.URLClassLoader.defineClass(URLClassLoader.java:468)
	at java.net.URLClassLoader.access$100(URLClassLoader.java:74)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:369)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:363)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:362)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.loadClass(RemoteTestRunner.java:766)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.loadClasses(RemoteTestRunner.java:490)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:513)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:756)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:452)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:210)

All of my VS Code settings and launch file configurations do not specify an explicit JDK version and I have confirmed that VS Code is launching and utilizing Java 11, not 8.

Why does my test runner run in a Java 8 context?

[jdneo]

Would you mind to share a sample project for this issue? I can try it on my side to see what's going on.

[ryno1234]

It might be easier for me to ask what determines what version of the java runtime that is launched during test execution? I've confirmed in my task manager in Windows that 1.8 is launched when I execute a test.

What is the switch for this?

[jdneo]

It's determined by the Java Language Server.

There is a setting called java.configuration.runtimes that maps the jdk versions to the installation location on your machine.

For example, let's say you are using Maven for your project, and set the Java version to 11. Then, the Java Language Server will automatically pick the matchest JDK to launch it.

[ryno1234]

Ah - Ok. So my issue is with my configuration as it relates to the Java Language Server. That's what I thought after further investigation myself. I did end up posting my question over in the Java Pack Extension repo: microsoft/vscode-java-pack#750 but I'll submit something over to the Java Language Server project to see if I can get some assistance.

Thank you for your help.

[ryno1234]

SOLVED: For anyone landing here through search, my issue was the Java Language Server was not correctly picking up my target Java version as configured in my Maven pom.xml. This was able to be confirmed via the Configure Java Runtime screen accessible by pressing ctrl + shift + p to access the command palette and entering "Java: Configure Java Runtime".

To fix this, I needed to execute a "Java: Clean Java Language Server Workspace" command. After completing that, all my projects correctly had their Java versions identified.

[jdneo]

Thank you @ryno1234 for providing the detailed information!

Closing this issue since it's been resolved.