Fix Javadoc warnings

Change-Id: Ia5fe7785f76da92abbf940599cbd3d7dc6ac2cc5
diff --git a/core/api/src/main/java/org/onosproject/codec/CodecContext.java b/core/api/src/main/java/org/onosproject/codec/CodecContext.java
index 3189e10..1898e93 100644
--- a/core/api/src/main/java/org/onosproject/codec/CodecContext.java
+++ b/core/api/src/main/java/org/onosproject/codec/CodecContext.java
@@ -56,6 +56,7 @@
      *
      * @param json    JSON to decode
      * @param entityClass entity class
+     * @param <T> entity type
      * @return decoded entity
      */
     default <T> T decode(JsonNode json, Class<T> entityClass) {
@@ -69,6 +70,7 @@
      *
      * @param entity  entity to encode
      * @param entityClass entity class
+     * @param <T> entity type
      * @return JSON node
      */
     default <T> ObjectNode encode(T entity, Class<T> entityClass) {