How to get first level supper class in freemarker template by java reflection?

suppose that i have a these below classes:

public abstract class A<T>  implements Serializable {

}

public class B extends A<Long> {

}

public class C extends B {

}

public class D {
     public C c;
}

then, i want to generate code using these below codes and template:

private static void generateJavaCode(Class clazz) {
        try {
            Configuration cfg = new Configuration();
            FileTemplateLoader ftl1 = new FileTemplateLoader(new File("E:/templates/code/"));
            cfg.setTemplateLoader(ftl1);

            Template template = cfg.getTemplate(tmpl);
            Map<String, Object> data = new HashMap<String, Object>();

            String modelPackage = clazz.getPackage().getName();

            data.put("fields", clazz.getDeclaredFields());

            File f = new File(filePath);
            String absolutePath = f.getAbsolutePath();
            String ffilePath = absolutePath.substring(0, absolutePath.lastIndexOf(File.separator));
            new File(ffilePath).mkdirs();
            Writer file = new FileWriter(f);
            template.process(data, file);
            file.flush();
            file.close();
        }
        catch (Exception e) {
        }
    }

and this is the content of .ftl file:

<#list fields as field>
    <#attempt>
         field.superclass.superclass
    <#recover>
         field.superclass
    </#attempt>
</#list>

but field.superclass.superclass doesn't work, how can i solve this problem?