Split EventStream and EventStore

src/main/kotlin/eventDemo/libs/event/EventStoreInMemory.kt

@@ -0,0 +1,12 @@
+package eventDemo.libs.event
+
+import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.ConcurrentMap
+
+class EventStoreInMemory<E : Event<ID>, ID : AggregateId> : EventStore<E, ID> {
+    private val streams: ConcurrentMap<ID, EventStream<E>> = ConcurrentHashMap()
+
+    override fun getStream(aggregateId: ID): EventStream<E> = streams.computeIfAbsent(aggregateId) { EventStreamInMemory() }
+
+    override fun publish(event: E) = getStream(event.aggregateId).publish(event)
+}