RalmKitAnnotationProcessor

@AutoService(Processor.class)
public class RalmKitAnnotationProcessor extends AbstractProcessor {

    private Types typeUtils;
    private Elements elementUtils;
    private Filer filer;
    private Messager messager;

    @Override
    public synchronized void init(ProcessingEnvironment processingEnv) {
        super.init(processingEnv);
        typeUtils = processingEnv.getTypeUtils();
        elementUtils = processingEnv.getElementUtils();
        filer = processingEnv.getFiler();
        messager = processingEnv.getMessager();
    }

    @Override
    public Set<String> getSupportedAnnotationTypes() {
        Set<String> annotataions = new LinkedHashSet<String>();
        annotataions.add(RealmKitObject.class.getCanonicalName());
        return annotataions;
    }

    @Override
    public SourceVersion getSupportedSourceVersion() {
        return SourceVersion.latestSupported();
    }


    @Override
    public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {

        for (Element e : roundEnv.getElementsAnnotatedWith(RealmKitObject.class)) {
            try {

                RealmKitObjectGenerator generator = new RealmKitObjectGenerator(e);
                generator.writeTo(filer);

            } catch (IOException e1) {
                e1.printStackTrace();
            }
        }
        return true;
    }

}

RealmKitObjectGenerator

public class RealmKitObjectGenerator {

    private JavaFile javaFile;

    public RealmKitObjectGenerator(Element element) {

        String kitName = element.getSimpleName().toString();


        MethodSpec createOrUpdate = MethodSpec.methodBuilder("createOrUpdate")
                .addModifiers(Modifier.PUBLIC)
                .returns(void.class)
                        // .addParameter(type, kitName.toLowerCase())
                .addStatement("$T.out.println($S)", System.class, "Hello, JavaPoet! " + kitName)
                .build();


        TypeSpec realmKit = TypeSpec.classBuilder(kitName + "Kit")
                .addModifiers(Modifier.PUBLIC)
                .addMethod(createOrUpdate)
                .build();


        javaFile = JavaFile.builder("com.timewastingguru.customannotations", realmKit)
                .build();
    }

    public void writeTo(Filer filer) throws IOException {
        javaFile.writeTo(filer);

    }

}