public Map<String, Gauge<Long>> gauges() {
        Map<String, Gauge<Long>> gauges = new HashMap<>();

        final TrafficCounter tc = trafficCounter();

        gauges.put(READ_BYTES_1_SEC, new Gauge<Long>() {
            @Override
            public Long getValue() {
                return tc.lastReadBytes();
            }
        });
        gauges.put(WRITTEN_BYTES_1_SEC, new Gauge<Long>() {
            @Override
            public Long getValue() {
                return tc.lastWrittenBytes();
            }
        });
        gauges.put(READ_BYTES_TOTAL, new Gauge<Long>() {
            @Override
            public Long getValue() {
                return tc.cumulativeReadBytes();
            }
        });
        gauges.put(WRITTEN_BYTES_TOTAL, new Gauge<Long>() {
            @Override
            public Long getValue() {
                return tc.cumulativeWrittenBytes();
            }
        });

        return gauges;
    }
@Test
    public void counterReturnsZeroIfNoInteraction() {
        channel.finish();

        final Map<String, Gauge<Long>> gauges = throughputCounter.gauges();
        assertThat(gauges.get(ThroughputCounter.READ_BYTES_1_SEC).getValue()).isEqualTo(0L);
        assertThat(gauges.get(ThroughputCounter.WRITTEN_BYTES_1_SEC).getValue()).isEqualTo(0L);
        assertThat(gauges.get(ThroughputCounter.READ_BYTES_TOTAL).getValue()).isEqualTo(0L);
        assertThat(gauges.get(ThroughputCounter.WRITTEN_BYTES_TOTAL).getValue()).isEqualTo(0L);
    }