OfframpClientImpl implements OfframpClient<T> { @Override public Mono<Boolean> commit(Map<Integer, Long> offsets) { return commitHandler.commit(offsets); } OfframpClientImpl(OfframpOptions<T> options);   OfframpClientImpl(
      OfframpOptions<T> options,
      WebSocket.Factory socketFactory,
      CommitHandler.Factory commitHandlerFactory); @Override Publisher<Message<T>> messages(); @Override Mono<Boolean> commit(Map<Integer, Long> offsets); @Override Publisher<Set<Integer>> rebalances(); @Override void close();  }
@Test public void commit() throws Exception { doReturn(Mono.just(true)).when(commitHandler).commit(singletonMap(0, 1L)); Boolean result = underTest.commit(singletonMap(0, 1L)).block(); assertThat(result, is(true)); }