ONOS-2330: Fixes bug in MapValue.isNewerThan

Change-Id: I2a1bb9299e69254754d4ad6b500a8be0b511211a
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 aa57962..1a89c6b 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
@@ -1,7 +1,24 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.onosproject.store.ecmap;
 
 import org.onosproject.store.Timestamp;
+
 import com.google.common.base.MoreObjects;
+import com.google.common.base.Objects;
 
 /**
  * Representation of a value in EventuallyConsistentMap.
@@ -54,7 +71,7 @@
     }
 
     public boolean isNewerThan(Timestamp timestamp) {
-        return timestamp.isNewerThan(timestamp);
+        return this.timestamp.isNewerThan(timestamp);
     }
 
     public Digest digest() {
@@ -62,6 +79,21 @@
     }
 
     @Override
+    public int hashCode() {
+        return Objects.hashCode(timestamp, value);
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other instanceof MapValue) {
+            MapValue<V> that = (MapValue) other;
+            return Objects.equal(this.timestamp, that.timestamp) &&
+                    Objects.equal(this.value, that.value);
+        }
+        return false;
+    }
+
+    @Override
     public String toString() {
         return MoreObjects.toStringHelper(getClass())
                 .add("timestamp", timestamp)
@@ -100,6 +132,21 @@
         }
 
         @Override
+        public int hashCode() {
+            return Objects.hashCode(timestamp, isTombstone);
+        }
+
+        @Override
+        public boolean equals(Object other) {
+            if (other instanceof Digest) {
+                Digest that = (Digest) other;
+                return Objects.equal(this.timestamp, that.timestamp) &&
+                        Objects.equal(this.isTombstone, that.isTombstone);
+            }
+            return false;
+        }
+
+        @Override
         public String toString() {
             return MoreObjects.toStringHelper(getClass())
                     .add("timestamp", timestamp)