1 files changed, 47 insertions, 0 deletions
diff --git a/kamon-core/src/legacy-main/scala/kamon/metric/MetricKey.scala b/kamon-core/src/legacy-main/scala/kamon/metric/MetricKey.scala
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+++ b/kamon-core/src/legacy-main/scala/kamon/metric/MetricKey.scala
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+/*
+ * =========================================================================================
+ * Copyright © 2013-2015 the kamon project <http://kamon.io/>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+
+package kamon.metric
+
+import kamon.metric.instrument.UnitOfMeasurement
+
+/**
+ *  MetricKeys are used to identify a given metric in entity recorders and snapshots.
+ */
+sealed trait MetricKey {
+  def name: String
+  def unitOfMeasurement: UnitOfMeasurement
+}
+
+/**
+ *  MetricKey for all Histogram-based metrics.
+ */
+private[kamon] case class HistogramKey(name: String, unitOfMeasurement: UnitOfMeasurement) extends MetricKey
+
+/**
+ *  MetricKey for all MinMaxCounter-based metrics.
+ */
+private[kamon] case class MinMaxCounterKey(name: String, unitOfMeasurement: UnitOfMeasurement) extends MetricKey
+
+/**
+ *  MetricKey for all Gauge-based metrics.
+ */
+private[kamon] case class GaugeKey(name: String, unitOfMeasurement: UnitOfMeasurement) extends MetricKey
+
+/**
+ *  MetricKey for all Counter-based metrics.
+ */
+private[kamon] case class CounterKey(name: String, unitOfMeasurement: UnitOfMeasurement) extends MetricKey