diff --git a/src/test/java/com/intel/jndn/mock/MockFaceTest.java b/src/test/java/com/intel/jndn/mock/MockFaceTest.java
index 6bbbdda..afab856 100644
--- a/src/test/java/com/intel/jndn/mock/MockFaceTest.java
+++ b/src/test/java/com/intel/jndn/mock/MockFaceTest.java
@@ -150,7 +150,7 @@
   public void testRegistrationConnectsTransport() throws IOException, SecurityException {
     MockFace face = new MockFace();
     assertFalse(face.getTransport().getIsConnected());
-    face.registerPrefix(new Name("/fake/prefix"), null, null);
+    face.registerPrefix(new Name("/fake/prefix"), (OnInterest) null, null);
     assertTrue(face.getTransport().getIsConnected());
   }
 }