static Map<Class<?>, EventProducer> findAllProducers(Object listener) {
    final Class<?> listenerClass = listener.getClass();
    Map<Class<?>, EventProducer> handlersInMethod = new HashMap<Class<?>, EventProducer>();

    Map<Class<?>, Method> methods = PRODUCERS_CACHE.get(listenerClass);
    if (null == methods) {
      methods = new HashMap<Class<?>, Method>();
      loadAnnotatedProducerMethods(listenerClass, methods);
    }
    if (!methods.isEmpty()) {
      for (Map.Entry<Class<?>, Method> e : methods.entrySet()) {
        EventProducer producer = new EventProducer(listener, e.getValue());
        handlersInMethod.put(e.getKey(), producer);
      }
    }

    return handlersInMethod;
  }
This implementation finds all methods marked with a {@link Produce} annotation.
otto/src/main/java/com/squareup/otto/AnnotatedHandlerFinder.java