Started adding putIfAbsent to LruAssignmentCache (#221)

* Started adding putIfAbsent to LruAssignmentCache

* spotless, common v3.13

---------

Co-authored-by: Tyler Potter <[email protected]>

Author: hbordersTwitch

eppo/build.gradle

@@ -68,7 +68,7 @@ ext.versions = [
 ]
 
 dependencies {
-    api 'cloud.eppo:sdk-common-jvm:3.12.2'
+    api 'cloud.eppo:sdk-common-jvm:3.13.0'
 
     implementation 'org.slf4j:slf4j-api:2.0.17'
 

eppo/src/main/java/cloud/eppo/android/cache/LRUAssignmentCache.java

@@ -20,6 +20,19 @@ public void put(String cacheKey, @NonNull String serializedEntry) {
           public String get(String cacheKey) {
             return cache.get(cacheKey);
           }
+
+          @Override
+          public boolean putIfAbsent(String cacheKey, @NonNull String serializedEntry) {
+            boolean hadNoPreviousEntry;
+            synchronized (cache) {
+              String entry = cache.get(cacheKey);
+              hadNoPreviousEntry = entry == null;
+              if (hadNoPreviousEntry) {
+                cache.put(cacheKey, serializedEntry);
+              }
+            }
+            return hadNoPreviousEntry;
+          }
         });
   }
 }