classMetaData = new ClassMetaData(className)
            }
            try {
                gradlebuild.docs.dsl.docbook.model.ClassExtensionMetaData extensionMetaData = extensionMetaData[className]
                if (!extensionMetaData) {
                    extensionMetaData = new gradlebuild.docs.dsl.docbook.model.ClassExtensionMetaData(className)
                }
                File classFile = getFileForClass(className)

                plugins.put(pluginId, classExtensionDoc);
            }
            classExtensionDoc.getMixinClasses().add(model.getClassDoc(mixin.getMixinClass()));
        }
        for (ExtensionMetaData extension : classDoc.getExtensionMetaData().getExtensionClasses()) {
            String pluginId = extension.getPluginId();
            ClassExtensionDoc classExtensionDoc = plugins.get(pluginId);