Refeactor codec helper classes

Change-Id: Ic980293f5df97ed74a73fc54e3dcb197658264f5
diff --git a/core/common/src/main/java/org/onosproject/codec/impl/CriterionCodec.java b/core/common/src/main/java/org/onosproject/codec/impl/CriterionCodec.java
index 98cd3bd..8a6a729 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/CriterionCodec.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/CriterionCodec.java
@@ -63,13 +63,13 @@
 
     @Override
     public ObjectNode encode(Criterion criterion, CodecContext context) {
-        EncodeCriterionCodec encoder = new EncodeCriterionCodec(criterion, context);
+        EncodeCriterionCodecHelper encoder = new EncodeCriterionCodecHelper(criterion, context);
         return encoder.encode();
     }
 
     @Override
     public Criterion decode(ObjectNode json, CodecContext context) {
-        DecodeCriterionCodec decoder = new DecodeCriterionCodec(json);
+        DecodeCriterionCodecHelper decoder = new DecodeCriterionCodecHelper(json);
         return decoder.decode();
     }