Unable to add external jar to work with LSP

[keys-i]

I'm using Visual Studio Code for a Java project without build tools (e.g., Maven or Gradle). I've added JAR files using the java.project.referencedLibraries setting. While auto-completion and documentation pop-ups work, there is no proper syntax highlighting (LSP-based) for the referenced classes and methods within the JARs.

Steps to Reproduce:

1. Open a Java project in VS Code.
2. Add JAR files directly to the java.project.referencedLibraries setting.
3. Use a class or method from the JAR in your code.

Expected Behavior:

LSP features should include syntax highlighting for classes and methods from the JARs, in addition to auto-completion and documentation pop-ups.

Actual Behavior:

While auto-completion and documentation pop-ups work, syntax highlighting does not apply for the JAR dependencies.

Screenshot:

• Referencing the JAR:
  
• Missing syntax highlighting:
  

Additional Context:

This issue occurs in a setup without Maven or Gradle. Are there additional configurations required to enable full syntax highlighting for JAR dependencies?

[fbricon]

can you provide a sample project reproducing the issue?

[keys-i]

I attempted to reproduce the issue using the following code:

import edu.duke.*;

public class PerimeterRunner {
    public double getPerimeter(Shape s) {
        double totalPerimeter = 0.0;  // Initialize perimeter to 0
        Point prevPt = s.getLastPoint();  // Start with the last point
        return totalPerimeter;
    }
}

I used the courserajava.jar library from this link, but I am still encountering the same error. Any suggestions on how to resolve this?

[fbricon]

Your example works for me. Your 1st screenshot shows syntax highlighting is working correctly. I don't know what your 2nd screenshot is supposed to show, but certainly not syntax highlighting.
It seems your problem is a compilation issue.

Because hovering over Point shows you proper documentation, the courserajava.jar is properly accessed by the Java language server.
The "cannot find symbol" error you're seeing is a javac specific error message, the source of that message (errors(3): 6:3-6:8) leads me to believe you installed a conflicting Java extension (likely the Oracle/Netbeans one). Try disabling all other Java-based extensions (i.e not from Red Hat or Microsoft) and try again.

[keys-i]

The error occurs when I have vscode-java enabled. I’ll try disabling each one to make sure if it’s a conflict issue.