code: protected void regenerateMetrics() {
      if(isInstrumentationEnabled()) {
        this.recordsMeter = Optional.of(this.metricContext.meter(MetricNames.RowLevelPolicyMetrics.RECORDS_IN_METER));
        this.passedRecordsMeter = Optional.of(
            this.metricContext.meter(MetricNames.RowLevelPolicyMetrics.RECORDS_PASSED_METER));
        this.failedRecordsMeter = Optional.of(
            this.metricContext.meter(MetricNames.RowLevelPolicyMetrics.RECORDS_FAILED_METER));
        this.policyTimer = Optional.<Timer>of(
            this.metricContext.timer(MetricNames.RowLevelPolicyMetrics.CHECK_TIMER));
      } else {
        this.recordsMeter = Optional.absent();
        this.passedRecordsMeter = Optional.absent();
        this.failedRecordsMeter = Optional.absent();
        this.policyTimer = Optional.absent();
      }
    }
docs: Generates metrics for the instrumentation of this class.