redhat-developer / redhat-developer/vscode-java
Spurious warning about incompatible .class files version in required binaries
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Description
When I add logback 1.5.6 as a dependency in my POM, vscode tells me: “Incompatible .class files version in required binaries. Project 'simple' is targeting a 17 runtime, but is compiled against '(…)/.m2/repository/ch/qos/logback/logback-core/1.5.6/logback-core-1.5.6.jar' (from the container 'Maven Dependencies') which requires a 21 runtime”.
I believe that the warning is incorrect: extracting the content of .m2/repository/ch/qos/logback/logback-core/1.5.6/logback-core-1.5.6.jar and running javap -verbose on a few classes reveal a major version equal to 55.
The JAR is a multi-release one, including some classes specific to Java 21. I suspect that this confuses vscode.
Environment
- Operating System: linux
- JDK version: 17
- Visual Studio Code version: 1.91.0
- Java extension version: v0.27.0
Steps To Reproduce
Add logback 1.5.6 as a dependency in your POM.
Here is a sample project.
Logs (partial and redacted): messages, server.
Current Result
Warning
Expected Result
No warning
Additional Informations
mvn compiledoes not complain.- Might be related to #3319.
- I posted an issue to logback before realizing that the problem seems to come from vscode.
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the linked Simple sample project, its POM, and the attached messages/server logs; reproduce on JDK 17 with logback 1.5.6 and inspect handling of multi-release JAR entries. Done means the sample no longer reports an incompatible class-file warning while Maven still compiles successfully.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- java, typescript
- Domain
- developer-experience, devtools
- Issue type
- Bug
- Difficulty
- 4/5
- Estimated time
- 3-5 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 38/100