GRÜN: Erwartungen implementiert

diff --git a/src/main/java/de/juplo/kafka/SumBusinessLogic.java b/src/main/java/de/juplo/kafka/SumBusinessLogic.java
index f7bf09f..74696a4 100644 (file)
--- a/src/main/java/de/juplo/kafka/SumBusinessLogic.java
+++ b/src/main/java/de/juplo/kafka/SumBusinessLogic.java
@@ -36,6 +36,13 @@ public class SumBusinessLogic
 
   public synchronized void addToSum(String user, Integer value)
   {
+    if (!state.containsKey(user))
+      throw new IllegalStateException("No sumation for " + user + " in progress");
+    if (value == null || value < 1)
+      throw new IllegalArgumentException("Not a positive number: " + value);
+
+    long result = state.get(user) + value;
+    state.put(user, result);
   }
 
   public synchronized Long endSum(String user)