Use lambda expression to simplify statements

Change-Id: Ib8ddac6e93327ade9d42984d8eba66be7047d051
diff --git a/core/store/dist/src/test/java/org/onosproject/store/link/impl/GossipLinkStoreTest.java b/core/store/dist/src/test/java/org/onosproject/store/link/impl/GossipLinkStoreTest.java
index bf7af46..f8b5b86 100644
--- a/core/store/dist/src/test/java/org/onosproject/store/link/impl/GossipLinkStoreTest.java
+++ b/core/store/dist/src/test/java/org/onosproject/store/link/impl/GossipLinkStoreTest.java
@@ -548,31 +548,22 @@
         final LinkKey linkId1 = LinkKey.linkKey(d1P1, d2P2);
 
         final CountDownLatch addLatch = new CountDownLatch(1);
-        LinkStoreDelegate checkAdd = new LinkStoreDelegate() {
-            @Override
-            public void notify(LinkEvent event) {
-                assertEquals(LINK_ADDED, event.type());
-                assertLink(linkId1, INDIRECT, event.subject());
-                addLatch.countDown();
-            }
+        LinkStoreDelegate checkAdd = event -> {
+            assertEquals(LINK_ADDED, event.type());
+            assertLink(linkId1, INDIRECT, event.subject());
+            addLatch.countDown();
         };
         final CountDownLatch updateLatch = new CountDownLatch(1);
-        LinkStoreDelegate checkUpdate = new LinkStoreDelegate() {
-            @Override
-            public void notify(LinkEvent event) {
-                assertEquals(LINK_UPDATED, event.type());
-                assertLink(linkId1, DIRECT, event.subject());
-                updateLatch.countDown();
-            }
+        LinkStoreDelegate checkUpdate = event -> {
+            assertEquals(LINK_UPDATED, event.type());
+            assertLink(linkId1, DIRECT, event.subject());
+            updateLatch.countDown();
         };
         final CountDownLatch removeLatch = new CountDownLatch(1);
-        LinkStoreDelegate checkRemove = new LinkStoreDelegate() {
-            @Override
-            public void notify(LinkEvent event) {
-                assertEquals(LINK_REMOVED, event.type());
-                assertLink(linkId1, DIRECT, event.subject());
-                removeLatch.countDown();
-            }
+        LinkStoreDelegate checkRemove = event -> {
+            assertEquals(LINK_REMOVED, event.type());
+            assertLink(linkId1, DIRECT, event.subject());
+            removeLatch.countDown();
         };
 
         linkStore.setDelegate(checkAdd);