Remove redundant casts
diff --git a/src/main/java/com/fasterxml/jackson/core/JsonFactory.java b/src/main/java/com/fasterxml/jackson/core/JsonFactory.java
index 68e0683..2e91c46 100644
--- a/src/main/java/com/fasterxml/jackson/core/JsonFactory.java
+++ b/src/main/java/com/fasterxml/jackson/core/JsonFactory.java
@@ -249,7 +249,7 @@
      * and this reuse only works within context of a single
      * factory instance.
      */
-    public JsonFactory() { this((ObjectCodec) null); }
+    public JsonFactory() { this(null); }
 
     public JsonFactory(ObjectCodec oc) { _objectCodec = oc; }