1 files changed, 63 insertions, 0 deletions
diff --git a/kamon-core/src/legacy-main/scala/kamon/metric/EntitySnapshot.scala b/kamon-core/src/legacy-main/scala/kamon/metric/EntitySnapshot.scala
new file mode 100644
index 00000000..16edecd8
--- /dev/null
+++ b/kamon-core/src/legacy-main/scala/kamon/metric/EntitySnapshot.scala
@@ -0,0 +1,63 @@
+/*
+ * =========================================================================================
+ * 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.{Counter, Histogram, CollectionContext, InstrumentSnapshot}
+import kamon.util.MapMerge
+import scala.reflect.ClassTag
+
+trait EntitySnapshot {
+  def metrics: Map[MetricKey, InstrumentSnapshot]
+  def merge(that: EntitySnapshot, collectionContext: CollectionContext): EntitySnapshot
+
+  def histogram(name: String): Option[Histogram.Snapshot] =
+    find[HistogramKey, Histogram.Snapshot](name)
+
+  def minMaxCounter(name: String): Option[Histogram.Snapshot] =
+    find[MinMaxCounterKey, Histogram.Snapshot](name)
+
+  def gauge(name: String): Option[Histogram.Snapshot] =
+    find[GaugeKey, Histogram.Snapshot](name)
+
+  def counter(name: String): Option[Counter.Snapshot] =
+    find[CounterKey, Counter.Snapshot](name)
+
+  def histograms: Map[HistogramKey, Histogram.Snapshot] =
+    filterByType[HistogramKey, Histogram.Snapshot]
+
+  def minMaxCounters: Map[MinMaxCounterKey, Histogram.Snapshot] =
+    filterByType[MinMaxCounterKey, Histogram.Snapshot]
+
+  def gauges: Map[GaugeKey, Histogram.Snapshot] =
+    filterByType[GaugeKey, Histogram.Snapshot]
+
+  def counters: Map[CounterKey, Counter.Snapshot] =
+    filterByType[CounterKey, Counter.Snapshot]
+
+  private def filterByType[K <: MetricKey, V <: InstrumentSnapshot](implicit keyCT: ClassTag[K]): Map[K, V] =
+    metrics.collect { case (k, v) if keyCT.runtimeClass.isInstance(k) ⇒ (k.asInstanceOf[K], v.asInstanceOf[V]) }
+
+  private def find[K <: MetricKey, V <: InstrumentSnapshot](name: String)(implicit keyCT: ClassTag[K]) =
+    metrics.find { case (k, v) ⇒ keyCT.runtimeClass.isInstance(k) && k.name == name } map (_._2.asInstanceOf[V])
+}
+
+class DefaultEntitySnapshot(val metrics: Map[MetricKey, InstrumentSnapshot]) extends EntitySnapshot {
+  import MapMerge.Syntax
+
+  override def merge(that: EntitySnapshot, collectionContext: CollectionContext): EntitySnapshot =
+    new DefaultEntitySnapshot(metrics.merge(that.metrics, (l, r) ⇒ l.merge(r, collectionContext)))
+}
+\ No newline at end of file