diff --git a/platform/util/src/com/intellij/util/containers/RefHashMap.java b/platform/util/src/com/intellij/util/containers/RefHashMap.java
index cba8230bdd72..057b96604e60 100644
--- a/platform/util/src/com/intellij/util/containers/RefHashMap.java
+++ b/platform/util/src/com/intellij/util/containers/RefHashMap.java
@@ -185,7 +185,8 @@ abstract class RefHashMap<K, V> extends AbstractMap<K, V> implements Map<K, V> {
   }
 
   @Override
-  public boolean containsKey(@NotNull Object key) {
+  public boolean containsKey(Object key) {
+    if (key == null) return false;
     // optimization:
     myHardKeyInstance.set((K)key);
     boolean result = myMap.containsKey(myHardKeyInstance);
@@ -194,7 +195,8 @@ abstract class RefHashMap<K, V> extends AbstractMap<K, V> implements Map<K, V> {
   }
 
   @Override
-  public V get(@NotNull Object key) {
+  public V get(Object key) {
+    if (key == null) return null;
     myHardKeyInstance.set((K)key);
     V result = myMap.get(myHardKeyInstance);
     myHardKeyInstance.clear();