GRÜN: Erwartungen implementiert

diff --git a/src/main/java/de/juplo/kafka/SumBusinessLogic.java b/src/main/java/de/juplo/kafka/SumBusinessLogic.java
index cea533f..e662606 100644 (file)
--- 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);
   }
 }