feat: improvements regarding cache map entry listener

horizon-core/src/main/java/de/telekom/eni/pandora/horizon/cache/service/JsonCacheServiceEntryListener.java

@@ -1,41 +1,74 @@
 package de.telekom.eni.pandora.horizon.cache.service;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
 import com.hazelcast.core.EntryEvent;
 import com.hazelcast.core.HazelcastJsonValue;
 import com.hazelcast.map.listener.EntryAddedListener;
 import com.hazelcast.map.listener.EntryEvictedListener;
 import com.hazelcast.map.listener.EntryRemovedListener;
 import com.hazelcast.map.listener.EntryUpdatedListener;
+import lombok.extern.slf4j.Slf4j;
 import org.springframework.context.ApplicationEventPublisher;
 
-public class JsonCacheServiceEntryListener implements EntryAddedListener<String, HazelcastJsonValue>,
+import java.util.Optional;
+
+@Slf4j
+public class JsonCacheServiceEntryListener<T> implements EntryAddedListener<String, HazelcastJsonValue>,
         EntryRemovedListener<String, HazelcastJsonValue>,
         EntryUpdatedListener<String, HazelcastJsonValue>,
         EntryEvictedListener<String, HazelcastJsonValue> {
 
+    private final Class<T> mapClass;
+
+    private final ObjectMapper mapper;
+
     private final ApplicationEventPublisher applicationEventPublisher;
 
-    public JsonCacheServiceEntryListener(ApplicationEventPublisher applicationEventPublisher) {
+    public JsonCacheServiceEntryListener(Class<T> mapClass, ObjectMapper mapper, ApplicationEventPublisher applicationEventPublisher) {
+        this.mapClass = mapClass;
+        this.mapper = mapper;
         this.applicationEventPublisher = applicationEventPublisher;
     }
 
+    private Optional<JsonCacheServiceEvent<T>> toJsonCacheServiceEvent(EntryEvent<String, HazelcastJsonValue> entryEvent) {
+        try {
+            T newValue = null;
+            T oldValue = null;
+
+            if (entryEvent.getValue() != null) {
+                newValue = mapper.readValue(entryEvent.getValue().getValue(), mapClass);
+            }
+
+            if (entryEvent.getOldValue() != null) {
+                oldValue = mapper.readValue(entryEvent.getOldValue().getValue(), mapClass);
+            }
+
+            return Optional.of(new JsonCacheServiceEvent<>(newValue, oldValue, entryEvent));
+        } catch (JsonProcessingException e) {
+            log.error(e.getMessage(), e);
+        }
+
+        return Optional.empty();
+    }
+
     @Override
     public void entryAdded(EntryEvent<String, HazelcastJsonValue> entryEvent) {
-        applicationEventPublisher.publishEvent(new JsonCacheServiceEvent(entryEvent));
+        toJsonCacheServiceEvent(entryEvent).ifPresent(applicationEventPublisher::publishEvent);
     }
 
     @Override
     public void entryEvicted(EntryEvent<String, HazelcastJsonValue> entryEvent) {
-        applicationEventPublisher.publishEvent(new JsonCacheServiceEvent(entryEvent));
+        toJsonCacheServiceEvent(entryEvent).ifPresent(applicationEventPublisher::publishEvent);
     }
 
     @Override
     public void entryRemoved(EntryEvent<String, HazelcastJsonValue> entryEvent) {
-        applicationEventPublisher.publishEvent(new JsonCacheServiceEvent(entryEvent));
+        toJsonCacheServiceEvent(entryEvent).ifPresent(applicationEventPublisher::publishEvent);
     }
 
     @Override
     public void entryUpdated(EntryEvent<String, HazelcastJsonValue> entryEvent) {
-        applicationEventPublisher.publishEvent(new JsonCacheServiceEvent(entryEvent));
+        toJsonCacheServiceEvent(entryEvent).ifPresent(applicationEventPublisher::publishEvent);
     }
 }

horizon-core/src/main/java/de/telekom/eni/pandora/horizon/cache/service/JsonCacheServiceEvent.java

@@ -9,7 +9,10 @@
 @Getter
 @Setter
 @AllArgsConstructor
-public class JsonCacheServiceEvent {
+public class JsonCacheServiceEvent<T> {
+    private T newValue;
+
+    private T oldValue;
 
     private EntryEvent<String, HazelcastJsonValue> entryEvent;
 }

horizon-spring-boot-autoconfigure/src/main/java/de/telekom/eni/pandora/horizon/autoconfigure/cache/JsonCacheAutoconfiguration.java

@@ -32,7 +32,7 @@ public JsonCacheService<SubscriptionResource> subscriptionCache(HazelcastInstanc
         mapper.registerModule(module);
 
         IMap<String, HazelcastJsonValue> map = hazelcastInstance.getMap(SUBSCRIPTION_RESOURCE_V1);
-        map.addEntryListener(new JsonCacheServiceEntryListener(applicationEventPublisher), true);
+        map.addEntryListener(new JsonCacheServiceEntryListener<>(SubscriptionResource.class, mapper, applicationEventPublisher), true);
         return new JsonCacheService<>(SubscriptionResource.class, map, mapper);
     }