diff --git a/EventBus/src/org/greenrobot/eventbus/SubscriberMethodFinder.java b/EventBus/src/org/greenrobot/eventbus/SubscriberMethodFinder.java
index 3f2812bc..88ffb79a 100644
--- a/EventBus/src/org/greenrobot/eventbus/SubscriberMethodFinder.java
+++ b/EventBus/src/org/greenrobot/eventbus/SubscriberMethodFinder.java
@@ -38,7 +38,7 @@ class SubscriberMethodFinder {
     private static final int MODIFIERS_IGNORE = Modifier.ABSTRACT | Modifier.STATIC | BRIDGE | SYNTHETIC;
     private static final Map<Class<?>, List<SubscriberMethod>> METHOD_CACHE = new ConcurrentHashMap<>();
 
-    private List<SubscriberInfoIndex> subscriberInfoIndexes;
+    private final List<SubscriberInfoIndex> subscriberInfoIndexes;
     private final boolean strictMethodVerification;
     private final boolean ignoreGeneratedIndex;