More Unit tests

Change-Id: I32dd3851e490979621c4a5205c6e041dee900244
diff --git a/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapImpl.java b/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapImpl.java
index 2de8947..b56d74b 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapImpl.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/ecmap/EventuallyConsistentMapImpl.java
@@ -653,7 +653,7 @@
         public void processItems(List<UpdateEntry<K, V>> items) {
             Map<K, UpdateEntry<K, V>> map = Maps.newHashMap();
             items.forEach(item -> map.compute(item.key(), (key, existing) ->
-                    existing == null || item.compareTo(existing) > 0 ? item : existing));
+                    item.isNewerThan(existing) ? item : existing));
             communicationExecutor.submit(() -> {
                 clusterCommunicator.unicast(ImmutableList.copyOf(map.values()),
                                             updateMessageSubject,
diff --git a/core/store/dist/src/main/java/org/onosproject/store/ecmap/MapValue.java b/core/store/dist/src/main/java/org/onosproject/store/ecmap/MapValue.java
index 1a89c6b..bb69b47 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/ecmap/MapValue.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/ecmap/MapValue.java
@@ -83,10 +83,11 @@
         return Objects.hashCode(timestamp, value);
     }
 
+    @SuppressWarnings("unchecked")
     @Override
     public boolean equals(Object other) {
         if (other instanceof MapValue) {
-            MapValue<V> that = (MapValue) other;
+            MapValue<V> that = (MapValue<V>) other;
             return Objects.equal(this.timestamp, that.timestamp) &&
                     Objects.equal(this.value, that.value);
         }
diff --git a/core/store/dist/src/main/java/org/onosproject/store/ecmap/UpdateEntry.java b/core/store/dist/src/main/java/org/onosproject/store/ecmap/UpdateEntry.java
index 41eb3a2..fcf6198 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/ecmap/UpdateEntry.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/ecmap/UpdateEntry.java
@@ -22,7 +22,7 @@
 /**
  * Describes a single update event in an EventuallyConsistentMap.
  */
-final class UpdateEntry<K, V> implements Comparable<UpdateEntry<K, V>> {
+final class UpdateEntry<K, V> {
     private final K key;
     private final MapValue<V> value;
 
@@ -55,9 +55,13 @@
         return value;
     }
 
-    @Override
-    public int compareTo(UpdateEntry<K, V> o) {
-        return this.value.timestamp().compareTo(o.value.timestamp());
+    /**
+     * Returns if this entry is newer than other entry.
+     * @param other other entry
+     * @return true if this entry is newer; false otherwise
+     */
+    public boolean isNewerThan(UpdateEntry<K, V> other) {
+        return other == null || value.isNewerThan(other.value);
     }
 
     @Override