pinpoint-apm/pinpoint · error · IllegalArgumentException

unknown scanner type classLoader:${classLoader} protectionDo

Error message

unknown scanner type classLoader:${classLoader} protectionDomain:${protectionDomain}

What it means

ClassScannerFactory.newScanner could not determine a scanner strategy for the given class: neither the ClassLoader nor the ProtectionDomain provided a usable class-loading source. It throws IllegalArgumentException describing both inputs.

Source

Thrown at agent-module/profiler/src/main/java/com/navercorp/pinpoint/profiler/instrument/scanner/ClassScannerFactory.java:59

        final URL codeLocation = CodeSourceUtils.getCodeLocation(protectionDomain);
        if (codeLocation == null) {
            return new ClassLoaderScanner(classLoader);
        }

        final Scanner scanner = newURLScanner(codeLocation);
        if (scanner != null) {
            return scanner;
        }

        // workaround for scanning for classes in nested jars - see newURLScanner(URL) below.
        if (FORCE_CLASS_LOADER_SCANNER || isNestedJar(codeLocation.getPath())) {
            ClassLoader protectionDomainClassLoader = protectionDomain.getClassLoader();
            if (protectionDomainClassLoader != null) {
                return new ClassLoaderScanner(protectionDomainClassLoader);
            }
        }

        throw new IllegalArgumentException("unknown scanner type classLoader:" + classLoader + " protectionDomain:" + protectionDomain);
    }

    public static Scanner newScanner(ProtectionDomain protectionDomain) {
        final URL codeLocation = CodeSourceUtils.getCodeLocation(protectionDomain);
        if (codeLocation == null) {
            return null;
        }

        final Scanner scanner = newURLScanner(codeLocation);
        if (scanner != null) {
            return scanner;
        }
        return null;
    }

    private static Scanner newURLScanner(URL codeLocation) {
        final String protocol = codeLocation.getProtocol();
        if (isFileProtocol(protocol)) {

View on GitHub (pinned to 744c3d3075)

Solutions

1. Provide a non-null ClassLoader when requesting the scanner
2. Ensure the ProtectionDomain has a class loader, or check CodeSource location handling so a JarFileScanner fallback applies
3. Skip/bootstrap-exclude classes whose loader is null in the transform filter

Example fix

// before
Scanner s = ClassScannerFactory.newScanner(null, protectionDomain); // both null -> throws
// after
ClassLoader cl = clazz.getClassLoader() != null ? clazz.getClassLoader() : Thread.currentThread().getContextClassLoader();
Scanner s = cl != null ? ClassScannerFactory.newScanner(cl, protectionDomain) : null;

if (classLoader == null && (protectionDomain == null || protectionDomain.getClassLoader() == null)) { /* skip or use fallback loader */ }

try { scanner = ClassScannerFactory.newScanner(classLoader, pd); } catch (IllegalArgumentException e) { log.warn("no scanner for class, skipping: {}", e.getMessage()); scanner = null; }

When it happens

Trigger: Calling newScanner with a null classLoader and a ProtectionDomain whose class loader is also null (e.g. bootstrap/primordial classes) so no scanner can be chosen.

Common situations: Instrumenting JDK/bootstrap classes loaded by the bootstrap classloader where getClassLoader() returns null and there is no jar fallback; custom classloading setups where classes are defined via reflection/unsafe with a null protection domain classloader.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• Transformer already exists. TransformKey:
• ${className} define fail Caused by:${causeMessage}
• J9BootLoader create fail Caused by:
• initialize fail Caused by:
• invoke fail Caused by:

AI-assisted analysis of pinpoint-apm/pinpoint@744c3d3075 (2026-09-07). Data as JSON: /api/errors/5abe01a03fb47a4a. Report an issue: GitHub.