code: private Invoker timed(Invoker invoker, List<Method> timedMethods) {
  
          ImmutableMap.Builder<String, Timer> timers = new ImmutableMap.Builder<>();
  
          for (Method m : timedMethods) {
              Timed annotation = m.getAnnotation(Timed.class);
              final String name = chooseName(annotation.name(), annotation.absolute(), m);
              Timer timer = metricRegistry.timer(name);
              timers.put(m.getName(), timer);
          }
  
          return new InstrumentedInvokers.TimedInvoker(invoker, timers.build());
      }
docs: Factory method for TimedInvoker.