oracle/graal · error · RuntimeException

No original class for type {}

Error message

No original class for type {}

What it means

HostVMAccess.getOriginalClass asks snippetReflection.originalClass(type) to map a ResolvedJavaType back to a host Class<?>; if the mapping is unknown it returns null and this RuntimeException is thrown (used by getPackage and other type->Class operations). It means the ResolvedJavaType was not created by / is not known to this host JVM's JVMCI backend, so no original class exists to reflect on.

Source

Thrown at compiler/src/jdk.graal.compiler.hostvmaccess/src/jdk/graal/compiler/hostvmaccess/HostVMAccess.java:442

    @Override
    public ResolvedJavaModule getModule(ResolvedJavaType type) {
        return new HostVMResolvedJavaModuleImpl(getOriginalClass(type).getModule());
    }

    @Override
    public ResolvedJavaPackage getPackage(ResolvedJavaType type) {
        Package pkg = getOriginalClass(type).getPackage();
        if (pkg == null) {
            return null;
        }
        return new HostVMResolvedJavaPackageImpl(providers.getMetaAccess(), pkg);
    }

    private Class<?> getOriginalClass(ResolvedJavaType type) {
        Class<?> originalClass = providers.getSnippetReflection().originalClass(type);
        if (originalClass == null) {
            throw new RuntimeException("No original class for type " + type);
        }
        return originalClass;
    }

    @Override
    public ResolvedJavaModuleLayer bootModuleLayer() {
        return new HostVMResolvedJavaModuleLayerImpl(ModuleLayer.boot());
    }

    @Override
    public URL getCodeSourceLocation(ResolvedJavaType type) {
        Class<?> originalClass = providers.getSnippetReflection().originalClass(type);
        ProtectionDomain pd = originalClass.getProtectionDomain();
        CodeSource cs = pd.getCodeSource();
        if (cs == null) {
            return null;
        }
        return cs.getLocation();

View on GitHub (pinned to a66e9ccd1d)

Solutions

1. Only pass types resolved by the same providers/MetaAccessProvider that backs this HostVMAccess
2. Use providers.getSnippetReflection().originalClass(type) yourself first and skip/branch when it returns null instead of letting the RuntimeException escape
3. Load the class on the host (e.g. via lookupAppClassLoaderType/Class.forName) and re-resolve the type so originalClass can map it

Example fix

// before
ResolvedJavaPackage pkg = vmAccess.getPackage(foreignType);

// after
if (providers.getSnippetReflection().originalClass(foreignType) == null) {
    // type unknown on this host - resolve it through this runtime first
    foreignType = providers.getMetaAccess().lookupJavaType(hostClass);
}
ResolvedJavaPackage pkg = vmAccess.getPackage(foreignType);

Class<?> hostClass = providers.getSnippetReflection().originalClass(type);
if (hostClass == null) {
    // type unknown to this host - re-resolve via this runtime or skip
}

catch (RuntimeException e) { if (e.getMessage().startsWith("No original class")) { fall back to type.getSourceName()/toJavaName based handling; } else throw e; }

When it happens

Trigger: Calling VMAccess.getPackage(type) (or any API routing through getOriginalClass) with a ResolvedJavaType resolved by a different JVMCI runtime, a guest-VM meta access, an unresolved or synthetic type, or a type whose class was never loaded reflectably on the host.

Common situations: Sharing ResolvedJavaType instances across two VMAccess implementations (host vs isolated); unit tests constructing mock/foreign ResolvedJavaType objects; types created from a class file stream without a corresponding host Class.

Related errors

• Could not unwrap array: {}
• Could not unwrap an array constant: {}
• Element {} should be a {}, got {}
• Element {} should be an object, got {}
• Expected an array constant, got {}

AI-assisted analysis of oracle/graal@a66e9ccd1d (2026-08-14). Data as JSON: /api/errors/449f8f1e02c70651. Report an issue: GitHub.