code: public static void logMetrics(MetricInfo metricInfo) {
          Map<String, Map<Integer, MetricSnapshot>> metrics = metricInfo.get_metrics();
          if (metrics != null) {
              LOG.info("\nprint metrics:");
              for (Map.Entry<String, Map<Integer, MetricSnapshot>> entry : metrics.entrySet()) {
                  String name = entry.getKey();
                  MetricSnapshot metricSnapshot = entry.getValue().get(AsmWindow.M1_WINDOW);
                  if (metricSnapshot != null) {
                      MetricType metricType = MetricType.parse(metricSnapshot.get_metricType());
                      double v;
                      if (metricType == MetricType.COUNTER) {
                          v = metricSnapshot.get_longValue();
                      } else if (metricType == MetricType.GAUGE) {
                          v = metricSnapshot.get_doubleValue();
                      } else if (metricType == MetricType.METER) {
                          v = metricSnapshot.get_m1();
                      } else if (metricType == MetricType.HISTOGRAM) {
                          v = metricSnapshot.get_mean();
                      } else {
                          v = 0;
                      }
                      LOG.info("{}|{}|{}", metricType, v, name);
                  }
              }
              LOG.info("\n");
          }
      }
docs: print default value for all metrics, in the format of: name|type|value