Implementierung des Adders für SumUp

[demos/kafka/training] / src / main / java / de / juplo / kafka / AdderBusinessLogic.java

diff --git a/src/main/java/de/juplo/kafka/AdderBusinessLogic.java b/src/main/java/de/juplo/kafka/AdderBusinessLogic.java
index df8c5f9..c0a4332 100644 (file)
--- a/src/main/java/de/juplo/kafka/AdderBusinessLogic.java
+++ b/src/main/java/de/juplo/kafka/AdderBusinessLogic.java
@@ -32,6 +32,30 @@ public class AdderBusinessLogic
 
   public synchronized Optional<Long> getSum(String user)
   {
-    return Optional.empty();
+    return Optional.ofNullable(state.get(user));
+  }
+
+  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)
+  {
+    if (!state.containsKey(user))
+      throw new IllegalStateException("No sumation for " + user + " in progress");
+
+    return state.get(user);
+  }
+
+  protected Map<String, Long> getState()
+  {
+    return state;
   }
 }