code: private CounterMetricFamily fromCounter(List<Map.Entry<MetricName, Counter>> countersWithSameName) {
  		final Map.Entry<MetricName, Counter> first = countersWithSameName.get(0);
  		final MetricName firstName = first.getKey();
  		final CounterMetricFamily metricFamily = new CounterMetricFamily(firstName.getName(), getHelpMessage(firstName, first.getValue()), firstName.getTagKeys());
  		for (Map.Entry<MetricName, Counter> entry : countersWithSameName) {
  			metricFamily.addMetric(entry.getKey().getTagValues(), entry.getValue().getCount());
  		}
  		return metricFamily;
  	}
docs: Export counter as prometheus counter.