Akka/Scala example source code file (AkkaConsoleReporter.scala)

This example Akka source code file (AkkaConsoleReporter.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

akka, classtag, consolewidth, counter, gauge, hdrhistogram, histogram, meter, metrics, reflection, string, t, test, testing, testkit, timer

The AkkaConsoleReporter.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */
package akka.testkit.metrics.reporter

import java.io.PrintStream
import java.util
import java.util.concurrent.TimeUnit
import com.codahale.metrics._
import akka.testkit.metrics._
import scala.reflect.ClassTag

/**
 * Used to report [[Metric]] types that the original [[ConsoleReporter]] is unaware of (cannot re-use directly because of private constructor).
 */
class AkkaConsoleReporter(
  registry: AkkaMetricRegistry,
  verbose: Boolean,
  output: PrintStream = System.out)
  extends ScheduledReporter(registry.asInstanceOf[MetricRegistry], "akka-console-reporter", MetricFilter.ALL, TimeUnit.SECONDS, TimeUnit.NANOSECONDS) {

  private final val ConsoleWidth = 80

  override def report(gauges: util.SortedMap[String, Gauge[_]], counters: util.SortedMap[String, Counter], histograms: util.SortedMap[String, Histogram], meters: util.SortedMap[String, Meter], timers: util.SortedMap[String, Timer]) {
    import collection.JavaConverters._

    // default Metrics types
    printMetrics(gauges.asScala, printGauge)
    printMetrics(counters.asScala, printCounter)
    printMetrics(histograms.asScala, printHistogram)
    printMetrics(meters.asScala, printMeter)
    printMetrics(timers.asScala, printTimer)

    // custom Akka types
    printMetrics(registry.getKnownOpsInTimespanCounters, printKnownOpsInTimespanCounter)
    printMetrics(registry.getHdrHistograms, printHdrHistogram)
    printMetrics(registry.getAveragingGauges, printAveragingGauge)

    output.println()
    output.flush()
  }

  def printMetrics[T <: Metric](metrics: Iterable[(String, T)], printer: T ⇒ Unit)(implicit clazz: ClassTag[T]) {
    if (!metrics.isEmpty) {
      printWithBanner(s"-- ${simpleName(metrics.head._2.getClass)}", '-')
      for ((key, metric) ← metrics) {
        output.println("  " + key)
        printer(metric)
      }
      output.println()
    }
  }

  private def printMeter(meter: Meter) {
    output.print("             count = %d%n".format(meter.getCount))
    output.print("         mean rate = %2.2f events/%s%n".format(convertRate(meter.getMeanRate), getRateUnit))
    output.print("     1-minute rate = %2.2f events/%s%n".format(convertRate(meter.getOneMinuteRate), getRateUnit))
    output.print("     5-minute rate = %2.2f events/%s%n".format(convertRate(meter.getFiveMinuteRate), getRateUnit))
    output.print("    15-minute rate = %2.2f events/%s%n".format(convertRate(meter.getFifteenMinuteRate), getRateUnit))
  }

  private def printCounter(entry: Counter) {
    output.print("             count = %d%n".format(entry.getCount))
  }

  private def printGauge(entry: Gauge[_]) {
    output.print("             value = %s%n".format(entry.getValue))
  }

  private def printHistogram(histogram: Histogram) {
    val snapshot = histogram.getSnapshot
    output.print("             count = %d%n".format(histogram.getCount))
    output.print("               min = %d%n".format(snapshot.getMin))
    output.print("               max = %d%n".format(snapshot.getMax))
    output.print("              mean = %2.2f%n".format(snapshot.getMean))
    output.print("            stddev = %2.2f%n".format(snapshot.getStdDev))
    output.print("            median = %2.2f%n".format(snapshot.getMedian))
    output.print("              75%% <= %2.2f%n".format(snapshot.get75thPercentile))
    output.print("              95%% <= %2.2f%n".format(snapshot.get95thPercentile))
    output.print("              98%% <= %2.2f%n".format(snapshot.get98thPercentile))
    output.print("              99%% <= %2.2f%n".format(snapshot.get99thPercentile))
    output.print("            99.9%% <= %2.2f%n".format(snapshot.get999thPercentile))
  }

  private def printTimer(timer: Timer) {
    val snapshot = timer.getSnapshot
    output.print("             count = %d%n".format(timer.getCount))
    output.print("         mean rate = %2.2f calls/%s%n".format(convertRate(timer.getMeanRate), getRateUnit))
    output.print("     1-minute rate = %2.2f calls/%s%n".format(convertRate(timer.getOneMinuteRate), getRateUnit))
    output.print("     5-minute rate = %2.2f calls/%s%n".format(convertRate(timer.getFiveMinuteRate), getRateUnit))
    output.print("    15-minute rate = %2.2f calls/%s%n".format(convertRate(timer.getFifteenMinuteRate), getRateUnit))
    output.print("               min = %2.2f %s%n".format(convertDuration(snapshot.getMin), getDurationUnit))
    output.print("               max = %2.2f %s%n".format(convertDuration(snapshot.getMax), getDurationUnit))
    output.print("              mean = %2.2f %s%n".format(convertDuration(snapshot.getMean), getDurationUnit))
    output.print("            stddev = %2.2f %s%n".format(convertDuration(snapshot.getStdDev), getDurationUnit))
    output.print("            median = %2.2f %s%n".format(convertDuration(snapshot.getMedian), getDurationUnit))
    output.print("              75%% <= %2.2f %s%n".format(convertDuration(snapshot.get75thPercentile), getDurationUnit))
    output.print("              95%% <= %2.2f %s%n".format(convertDuration(snapshot.get95thPercentile), getDurationUnit))
    output.print("              98%% <= %2.2f %s%n".format(convertDuration(snapshot.get98thPercentile), getDurationUnit))
    output.print("              99%% <= %2.2f %s%n".format(convertDuration(snapshot.get99thPercentile), getDurationUnit))
    output.print("            99.9%% <= %2.2f %s%n".format(convertDuration(snapshot.get999thPercentile), getDurationUnit))
  }

  private def printKnownOpsInTimespanCounter(counter: KnownOpsInTimespanTimer) {
    import concurrent.duration._
    import PrettyDuration._
    output.print("               ops = %d%n".format(counter.getCount))
    output.print("              time = %s%n".format(counter.elapsedTime.nanos.pretty))
    output.print("             ops/s = %2.2f%n".format(counter.opsPerSecond))
    output.print("               avg = %s%n".format(counter.avgDuration.nanos.pretty))
  }

  private def printHdrHistogram(hist: HdrHistogram) {
    val data = hist.getData
    val unit = hist.unit
    output.print("               min = %d %s%n".format(data.getMinValue, unit))
    output.print("               max = %d %s%n".format(data.getMaxValue, unit))
    output.print("              mean = %2.2f %s%n".format(data.getMean, unit))
    output.print("            stddev = %2.2f%n".format(data.getStdDeviation))
    output.print("              75%% <= %d %s%n".format(data.getValueAtPercentile(75.0), unit))
    output.print("              95%% <= %d %s%n".format(data.getValueAtPercentile(95.0), unit))
    output.print("              98%% <= %d %s%n".format(data.getValueAtPercentile(98.0), unit))
    output.print("              99%% <= %d %s%n".format(data.getValueAtPercentile(99.0), unit))
    output.print("            99.9%% <= %d %s%n".format(data.getValueAtPercentile(99.9), unit))

    if (verbose)
      data.outputPercentileDistribution(output, 1)
  }

  private def printAveragingGauge(gauge: AveragingGauge) {
    output.print("                avg = %2.2f%n".format(gauge.getValue))
  }

  private def printWithBanner(s: String, c: Char) {
    output.print(s)
    output.print(' ')
    var i: Int = 0
    while (i < (ConsoleWidth - s.length - 1)) {
      output.print(c)
      i += 1
    }
    output.println()
  }

  /** Required for getting simple names of refined instances */
  private def simpleName(clazz: Class[_]): String = {
    val n = clazz.getName
    val i = n.lastIndexOf('.')
    n.substring(i + 1)
  }

}