private final Element methodsTable
    private final Element propertiesSection
    private final Element methodsSection
    ClassDoc superClass
    List<ClassDoc> interfaces = []
    List<ClassDoc> subClasses = []
    List<Element> comment = []

    ClassDoc(String className, Element classContent, Document targetDocument, ClassMetaData classMetaData, ClassExtensionMetaData extensionMetaData) {

                    }
                    classDoc.addClassBlock(new BlockDoc(methodDoc, property, type, multiValued));
                } else {
                    classDoc.addClassMethod(methodDoc);
                    signatures.add(method.getOverrideSignature());
                }
            }
        }

        for (ClassDoc supertype : classDoc.getSuperTypes()) {

     */
    void build(ClassDoc classDoc) {
        ClassMetaData classMetaData = classDoc.getClassMetaData();
        String superClassName = classMetaData.getSuperClassName();
        if (superClassName != null) {
            // Assume this is a class and so has implemented all properties and methods somewhere in the superclass hierarchy
            ClassDoc superClass = model.getClassDoc(superClassName);

        extensionMetaData.addMixin('a', 'org.gradle.ExtensionA2')
        extensionMetaData.addMixin('b', 'org.gradle.ExtensionB')
        ClassDoc extensionA1 = classDoc('org.gradle.ExtensionA1')
        ClassDoc extensionA2 = classDoc('org.gradle.ExtensionA2')
        ClassDoc extensionB = classDoc('org.gradle.ExtensionB')
        _ * docModel.getClassDoc('org.gradle.ExtensionA1') >> extensionA1

        PropertyMetaData propertyB = property('b', classMetaData, comment: 'prop b')
        ClassDoc superDoc = classDoc('org.gradle.SuperClass')
        PropertyDoc propertyDocA = propertyDoc('a')
        PropertyDoc propertyDocC = propertyDoc('c')

        ClassDoc superType1 = classDoc("org.gradle.SuperType1")
        ClassDoc superType2 = classDoc("org.gradle.SuperType2")

        def content = parse('''
<section>

        String className = typeTr.td[0].text().trim()
        gradlebuild.docs.dsl.docbook.model.ClassDoc classDoc = model.getClassDoc(className)
        typeTr.children = {
            td {
                link(linkend: classDoc.id) { literal(classDoc.simpleName) }
            }
            td(classDoc.description)
        }
    }

            </chapter>
        ''')

        ClassDoc classDoc = classDoc('org.gradle.Class', id: 'classId', content: sourceContent, comment: 'class comment')
        _ * classDoc.classProperties >> []
        _ * classDoc.classMethods >> []
        _ * classDoc.classBlocks >> []
        _ * classDoc.classExtensions >> []
        _ * classDoc.subClasses >> []

        when:
        def result = parse('<root/>')

        MethodDoc methodC = methodDoc('c')
        MethodDoc methodD = methodDoc('d')
        MethodDoc methodE = methodDoc('e')
        ClassDoc superClass = classDoc('org.gradle.SuperClass')
        ClassDoc superType1 = classDoc("org.gradle.SuperType1")
        ClassDoc superType2 = classDoc("org.gradle.SuperType2")

        def content = parse('''
<section>
    <section><title>Methods</title>
        <table>

 */
class ClassExtensionDoc {
    private final Set<ClassDoc> mixinClasses = []
    private final Map<String, ClassDoc> extensionClasses = [:]
    private final String pluginId
    final ClassDoc targetClass
    final List<PropertyDoc> extraProperties = []
    final List<BlockDoc> extraBlocks = []

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

        this.listener = listener;
    }

    /**
     * Builds the extension meta-data for the given class.
     */
    public void build(ClassDoc classDoc) {
        Map<String, ClassExtensionDoc> plugins = new HashMap<String, ClassExtensionDoc>();
        for (MixinMetaData mixin : classDoc.getExtensionMetaData().getMixinClasses()) {
            String pluginId = mixin.getPluginId();