apache/dubbo · error · IllegalArgumentException

No activate extensions for [${type}] found

Error message

No activate extensions for [${type}] found

What it means

Thrown by ExtensionAccessor.getFirstActivateExtension(type) when an ExtensionLoader exists for the type but getActivateExtensions() returns an empty list — meaning no extensions with matching @Activate conditions are currently active. The loader was found, but no implementation is eligible given the current activation criteria (URL, group, key, values).

Source

Thrown at dubbo-common/src/main/java/org/apache/dubbo/common/extension/ExtensionAccessor.java:61

    default <T> T getDefaultExtension(Class<T> type) {
        ExtensionLoader<T> extensionLoader = getExtensionLoader(type);
        return extensionLoader != null ? extensionLoader.getDefaultExtension() : null;
    }

    default <T> List<T> getActivateExtensions(Class<T> type) {
        ExtensionLoader<T> extensionLoader = getExtensionLoader(type);
        return extensionLoader != null ? extensionLoader.getActivateExtensions() : Collections.emptyList();
    }

    default <T> T getFirstActivateExtension(Class<T> type) {
        ExtensionLoader<T> extensionLoader = getExtensionLoader(type);
        if (extensionLoader == null) {
            throw new IllegalArgumentException("ExtensionLoader for [" + type + "] is not found");
        }
        List<T> extensions = extensionLoader.getActivateExtensions();
        if (extensions.isEmpty()) {
            throw new IllegalArgumentException("No activate extensions for [" + type + "] found");
        }
        return extensions.get(0);
    }

    default Set<String> getSupportedExtensions(Class<?> type) {
        ExtensionLoader<?> extensionLoader = getExtensionLoader(type);
        return extensionLoader != null ? extensionLoader.getSupportedExtensions() : Collections.emptySet();
    }
}

View on GitHub (pinned to 3a3043227f)

Solutions

1. Check the SPI config files (META-INF/dubbo/<interface>) for the type — ensure at least one implementation is annotated with @Activate.
2. Verify the @Activate annotation's group/key/value on the implementation matches the runtime context (PROVIDER vs CONSUMER).
3. If you just need any extension (not an activate-matched one), use getExtension(type, name) or getDefaultExtension(type) instead.
4. Use getActivateExtensions(type) which returns an empty list rather than throwing, then check isEmpty().

Example fix

// before
Filter f = accessor.getFirstActivateExtension(Filter.class); // empty -> throws

// after
List<Filter> filters = accessor.getActivateExtensions(Filter.class);
if (!filters.isEmpty()) {
    Filter f = filters.get(0);
} else {
    // handle: no matching @Activate filters
}

List<?> exts = accessor.getActivateExtensions(type);
if (exts.isEmpty()) {
    // no matching @Activate extension — use named/default instead
    return accessor.getDefaultExtension(type);
}

static boolean hasActivateExtensions(ExtensionAccessor accessor, Class<?> type) {
    return !accessor.getActivateExtensions(type).isEmpty();
}

try {
    return accessor.getFirstActivateExtension(type);
} catch (IllegalArgumentException e) {
    if (e.getMessage().contains("No activate extensions")) {
        return accessor.getDefaultExtension(type);
    } else throw e;
}

When it happens

Trigger: Calling getFirstActivateExtension(type) on a valid SPI interface that has no @Activate-annotated extensions, or whose @Activate-annotated extensions do not match the current activation context (wrong @Activate group, key, or value filters).

Common situations: Querying for activated filter or wrapper extensions that exist in the SPI config but whose @Activate(group=...) annotation doesn't match the current provider/consumer context. Also happens when the SPI config files are empty or contain only non-activate extensions. Common after upgrading when an extension's @Activate conditions changed.

Related errors

• ExtensionLoader for [${type}] is not found
• Unable to get ExtensionLoader for type: ${type.getName()}
• There is no merger to merge result.
• No such class name in {}
• Failed to compile class, cause: {}, class: {}, code: {} , s

AI-assisted analysis of apache/dubbo@3a3043227f (2026-08-14). Data as JSON: /api/errors/becc55a8d3e81caa. Report an issue: GitHub.