Logging improvements.

Change-Id: I79b9ff16a0000e4bd72022f02baef5c779ea1b48
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DistributedLeadershipManager.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DistributedLeadershipManager.java
index 787b372..dcb2dbd 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DistributedLeadershipManager.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DistributedLeadershipManager.java
@@ -87,7 +87,7 @@
 
     private static final int DELAY_BETWEEN_LEADER_LOCK_ATTEMPTS_SEC = 2;
     private static final int DEADLOCK_DETECTION_INTERVAL_SEC = 2;
-    private static final int LEADERSHIP_STATUS_UPDATE_INTERVAL = 2;
+    private static final int LEADERSHIP_STATUS_UPDATE_INTERVAL_SEC = 2;
 
     private static final KryoSerializer SERIALIZER = new KryoSerializer() {
         @Override
@@ -134,7 +134,7 @@
         deadLockDetectionExecutor.scheduleWithFixedDelay(
                 this::purgeStaleLocks, 0, DEADLOCK_DETECTION_INTERVAL_SEC, TimeUnit.SECONDS);
         leadershipStatusBroadcaster.scheduleWithFixedDelay(
-                this::sendLeadershipStatus, 0, LEADERSHIP_STATUS_UPDATE_INTERVAL, TimeUnit.SECONDS);
+                this::sendLeadershipStatus, 0, LEADERSHIP_STATUS_UPDATE_INTERVAL_SEC, TimeUnit.SECONDS);
 
         listenerRegistry = new AbstractListenerRegistry<>();
         eventDispatcher.addSink(LeadershipEvent.class, listenerRegistry);
@@ -190,7 +190,7 @@
 
     @Override
     public void runForLeadership(String path) {
-        log.info("Running for leadership for topic: {}", path);
+        log.trace("Running for leadership for topic: {}", path);
         activeTopics.add(path);
         tryLeaderLock(path);
     }
@@ -200,11 +200,11 @@
         activeTopics.remove(path);
         try {
             if (lockMap.remove(path, localNodeId)) {
-                log.info("Sucessfully gave up leadership for {}", path);
+                log.info("Gave up leadership for {}", path);
             }
             // else we are not the current owner.
         } catch (Exception e) {
-            log.warn("Failed to verify (and clear) any lock this node might be holding for {}", path, e);
+            log.debug("Failed to verify (and clear) any lock this node might be holding for {}", path, e);
         }
     }
 
@@ -244,7 +244,7 @@
                 }
             }
         } catch (Exception e) {
-            log.warn("Attempt to acquire leadership lock for topic {} failed", path, e);
+            log.debug("Attempt to acquire leadership lock for topic {} failed", path, e);
             retry(path);
         }
     }
@@ -300,7 +300,7 @@
             LeadershipEvent leadershipEvent =
                     SERIALIZER.decode(message.payload());
 
-            log.trace("Leadership Event: time = {} type = {} event = {}",
+            log.debug("Leadership Event: time = {} type = {} event = {}",
                     leadershipEvent.time(), leadershipEvent.type(),
                     leadershipEvent);
 
@@ -350,7 +350,7 @@
                     log.info("Lock for {} is held by {} which is currently inactive", path, nodeId);
                     try {
                         if (lockMap.remove(path, epoch)) {
-                            log.info("Successfully purged stale lock held by {} for {}", nodeId, path);
+                            log.info("Purged stale lock held by {} for {}", nodeId, path);
                             notifyRemovedLeader(path, nodeId, epoch);
                         }
                     } catch (Exception e) {
@@ -361,7 +361,7 @@
                     log.info("Lock for {} is held by {} when it not running for leadership.", path, nodeId);
                     try {
                         if (lockMap.remove(path, epoch)) {
-                            log.info("Successfully purged stale lock held by {} for {}", nodeId, path);
+                            log.info("Purged stale lock held by {} for {}", nodeId, path);
                             notifyRemovedLeader(path, nodeId, epoch);
                         }
                     } catch (Exception e) {
@@ -370,20 +370,24 @@
                 }
             });
         } catch (Exception e) {
-            log.warn("Failed cleaning up stale locks", e);
+            log.debug("Failed cleaning up stale locks", e);
         }
     }
 
     private void sendLeadershipStatus() {
-        leaderBoard.forEach((path, leadership) -> {
-            if (leadership.leader().equals(localNodeId)) {
-                LeadershipEvent event = new LeadershipEvent(LeadershipEvent.Type.LEADER_ELECTED, leadership);
-                clusterCommunicator.broadcast(
-                        new ClusterMessage(
-                                clusterService.getLocalNode().id(),
-                                LEADERSHIP_EVENT_MESSAGE_SUBJECT,
-                                SERIALIZER.encode(event)));
-            }
-        });
+        try {
+            leaderBoard.forEach((path, leadership) -> {
+                if (leadership.leader().equals(localNodeId)) {
+                    LeadershipEvent event = new LeadershipEvent(LeadershipEvent.Type.LEADER_ELECTED, leadership);
+                    clusterCommunicator.broadcast(
+                            new ClusterMessage(
+                                    clusterService.getLocalNode().id(),
+                                    LEADERSHIP_EVENT_MESSAGE_SUBJECT,
+                                    SERIALIZER.encode(event)));
+                }
+            });
+        } catch (Exception e) {
+            log.debug("Failed to send leadership updates", e);
+        }
     }
-}
\ No newline at end of file
+}