Map<String, ClassExtensionDoc> plugins = new HashMap<String, ClassExtensionDoc>();
        for (MixinMetaData mixin : classDoc.getExtensionMetaData().getMixinClasses()) {
            String pluginId = mixin.getPluginId();
            ClassExtensionDoc classExtensionDoc = plugins.get(pluginId);
            if (classExtensionDoc == null) {
                classExtensionDoc = new ClassExtensionDoc(pluginId, classDoc);

        title.appendChild(document.createTextNode(" plugin"));

        Element titleabbrev = document.createElement("titleabbrev");
        section.appendChild(titleabbrev);
        literal = document.createElement("literal");
        titleabbrev.appendChild(literal);
        literal.appendChild(document.createTextNode(extension.getPluginId()));

        title.appendChild(document.createTextNode(" plugin"));

        Element titleabbrev = document.createElement("titleabbrev");
        section.appendChild(titleabbrev);
        literal = document.createElement("literal");
        titleabbrev.appendChild(literal);
        literal.appendChild(document.createTextNode(extension.getPluginId()));

        title.appendChild(document.createTextNode(" plugin"));

        Element titleabbrev = document.createElement("titleabbrev");
        section.appendChild(titleabbrev);
        literal = document.createElement("literal");
        titleabbrev.appendChild(literal);
        literal.appendChild(document.createTextNode(extension.getPluginId()));

    final List<BlockDoc> extraBlocks = []

    ClassExtensionDoc(String pluginId, ClassDoc targetClass) {
        this.pluginId = pluginId
        this.targetClass = targetClass
    }

    String getPluginId() {
        return pluginId
    }

    Set<ClassDoc> getMixinClasses() {
        mixinClasses
    }

    Map<String, ClassDoc> getExtensionClasses() {
        return extensionClasses
    }