@Override protected void doEnqueue(final Callback<R> callback) {
      delegate.enqueue(new Callback<V>() {
        @Override public void onSuccess(V value) {
          try {
            callback.onSuccess(mapper.map(value));
          } catch (Throwable t) {
            callback.onError(t);
          }
        }

        @Override public void onError(Throwable t) {
          callback.onError(t);
        }
      });
    }
Returns a copy of this object, so you can make an identical follow-up request.
zipkin/src/main/java/zipkin2/Call.java