From 20ab53ca995a7244ff7fca318ea70b6c439a960a Mon Sep 17 00:00:00 2001
From: Kai Moritz <kai@juplo.de>
Date: Sat, 13 Aug 2022 15:19:54 +0200
Subject: [PATCH] =?utf8?q?GR=C3=9CN:=20Erwartungen=20implementiert?=
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---
 src/main/java/de/juplo/kafka/SumBusinessLogic.java | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/src/main/java/de/juplo/kafka/SumBusinessLogic.java b/src/main/java/de/juplo/kafka/SumBusinessLogic.java
index cea533f..e662606 100644
--- a/src/main/java/de/juplo/kafka/SumBusinessLogic.java
+++ b/src/main/java/de/juplo/kafka/SumBusinessLogic.java
@@ -6,11 +6,25 @@ import java.util.Map;
 
 public class SumBusinessLogic
 {
+  private final Map<String, Long> state;
+
+
   public SumBusinessLogic()
   {
+    this(new HashMap<>());
   }
 
+  public SumBusinessLogic(Map<String, Long> state)
+  {
+    this.state = state;
+  }
+
+
   public synchronized void startSum(String user)
   {
+    if (state.containsKey(user))
+      throw new IllegalStateException("Sumation for " + user + " already in progress, state: " + state.get(user));
+
+    state.put(user, 0l);
   }
 }
-- 
2.20.1