package de.juplo.kafka;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+
+
public class AdderBusinessLogic
{
+ private final Map<String, Long> state;
+
+
public AdderBusinessLogic()
{
+ this(new HashMap<>());
+ }
+
+ public AdderBusinessLogic(Map<String, Long> state)
+ {
+ this.state = state;
+ }
+
+
+ public synchronized Optional<Long> getSum(String user)
+ {
+ 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 calculate(String user)
+ {
+ if (!state.containsKey(user))
+ throw new IllegalStateException("No sumation for " + user + " in progress");
+
+ return state.remove(user);
}
- public synchronized void startSum(String user)
+ protected Map<String, Long> getState()
{
+ return state;
}
}