oracle/graal · error · GraalError

Cannot find class %s during LibGraal JNIConfiguration regist

Error message

Cannot find class %s during LibGraal JNIConfiguration registration

What it means

Error "Cannot find class %s during LibGraal JNIConfiguration registration" thrown in oracle/graal.

Source

Thrown at compiler/src/jdk.graal.compiler.libgraal/src/jdk/graal/compiler/libgraal/GetJNIConfig.java:172

    private Class<?> findClass(String name) {
        String internalName = name;
        if (name.startsWith("L") && name.endsWith(";")) {
            internalName = name.substring(1, name.length() - 1);
        }
        var primitive = forPrimitive(internalName);
        if (primitive != null) {
            return primitive;
        }
        try {
            return Class.forName(internalName, false, loader);
        } catch (ClassNotFoundException e) {
            String externalName = internalName.replace('/', '.');
            try {
                return Class.forName(externalName, false, loader);
            } catch (ClassNotFoundException e3) {
                // ignore
            }
            throw new GraalError(e, "Cannot find class %s during LibGraal JNIConfiguration registration", name);
        }
    }

    private void check(boolean condition, String format, Object... args) {
        if (!condition) {
            throw error(format, args);
        }
    }

    private GraalError error(String format, Object... args) {
        Path path = configFilePath;
        configFilePath = null; // prevent deletion
        String errorMessage = format.formatted(args);
        String errorLine = lines.get(lineNo - 1);
        throw new GraalError("Line %d of %s: %s%n%s%n%s generated by command: %s",
                        lineNo, path.toAbsolutePath(), errorMessage, errorLine, path, quotedCommand);

    }

View on GitHub (pinned to a66e9ccd1d)

Solutions

1. Fix the condition reported by the error: Cannot find class {} during LibGraal JNIConfiguration registration
2. Check the throwing call site and ensure its documented preconditions (argument values, types, environment, or configuration) are satisfied before the call.

Example fix

Validate inputs and environment so that the failing condition does not occur: Cannot find class {} during LibGraal JNIConfiguration registration

When it happens

Trigger: Thrown at compiler/src/jdk.graal.compiler.libgraal/src/jdk/graal/compiler/libgraal/GetJNIConfig.java:172 when the library encounters an invalid state.

Common situations: Occurs when a caller violates the contract guarded by this check: Cannot find class {} during LibGraal JNIConfiguration registration

AI-assisted analysis of oracle/graal@a66e9ccd1d (2026-08-14). Data as JSON: /api/errors/15f52b9bb4b9d7a7. Report an issue: GitHub.