Improve Follower's Snapshot

[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / behaviors / Follower.java

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
index 288ce32a64ec21286adda9cf3672f7b53d1bf506..4913d98c36e9090253cf0ea4ece40873a2d655cd 100644 (file)
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/Follower.java
@@ -16,8 +16,8 @@ import akka.cluster.Member;
 import akka.cluster.MemberStatus;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Stopwatch;
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Optional;
@@ -53,6 +53,7 @@ import org.opendaylight.controller.cluster.raft.persisted.Snapshot;
  * convert to candidate
  * </ul>
  */
+// Non-final for testing
 public class Follower extends AbstractRaftActorBehavior {
     private static final long MAX_ELECTION_TIMEOUT_FACTOR = 18;
 
@@ -69,11 +70,13 @@ public class Follower extends AbstractRaftActorBehavior {
         this(context, null, (short)-1);
     }
 
+    @SuppressFBWarnings(value = "MC_OVERRIDABLE_METHOD_CALL_IN_CONSTRUCTOR",
+        justification = "electionDuration() is not final for Candidate override")
     public Follower(final RaftActorContext context, final String initialLeaderId,
             final short initialLeaderPayloadVersion) {
         super(context, RaftState.Follower);
-        this.leaderId = initialLeaderId;
-        this.leaderPayloadVersion = initialLeaderPayloadVersion;
+        leaderId = initialLeaderId;
+        leaderPayloadVersion = initialLeaderPayloadVersion;
 
         initialSyncStatusTracker = new SyncStatusTracker(context.getActor(), getId(), context.getConfigParams()
             .getSyncIndexThreshold());
@@ -324,8 +327,8 @@ public class Follower extends AbstractRaftActorBehavior {
             shouldCaptureSnapshot.compareAndSet(false,
                     context.getReplicatedLog().shouldCaptureSnapshot(entry.getIndex()));
 
-            if (entry.getData() instanceof ServerConfigurationPayload) {
-                context.updatePeerIds((ServerConfigurationPayload)entry.getData());
+            if (entry.getData() instanceof ServerConfigurationPayload serverConfiguration) {
+                context.updatePeerIds(serverConfiguration);
             }
         }
 
@@ -452,12 +455,11 @@ public class Follower extends AbstractRaftActorBehavior {
             return this;
         }
 
-        if (!(message instanceof RaftRPC)) {
+        if (!(message instanceof RaftRPC rpc)) {
             // The rest of the processing requires the message to be a RaftRPC
             return null;
         }
 
-        final RaftRPC rpc = (RaftRPC) message;
         // If RPC request or response contains term T > currentTerm:
         // set currentTerm = T, convert to follower (§5.1)
         // This applies to all RPC messages and responses
@@ -468,14 +470,14 @@ public class Follower extends AbstractRaftActorBehavior {
             context.getTermInformation().updateAndPersist(rpc.getTerm(), null);
         }
 
-        if (rpc instanceof InstallSnapshot) {
-            handleInstallSnapshot(sender, (InstallSnapshot) rpc);
+        if (rpc instanceof InstallSnapshot installSnapshot) {
+            handleInstallSnapshot(sender, installSnapshot);
             restartLastLeaderMessageTimer();
             scheduleElection(electionDuration());
             return this;
         }
 
-        if (!(rpc instanceof RequestVote) || canGrantVote((RequestVote) rpc)) {
+        if (!(rpc instanceof RequestVote requestVote) || canGrantVote(requestVote)) {
             restartLastLeaderMessageTimer();
             scheduleElection(electionDuration());
         }
@@ -597,7 +599,7 @@ public class Follower extends AbstractRaftActorBehavior {
                         + "all members {} self member: {}", logName(), unreachable, members, selfMember);
 
         // no unreachable peers means we cannot be isolated
-        if (unreachable.size() == 0) {
+        if (unreachable.isEmpty()) {
             return false;
         }
 
@@ -607,11 +609,7 @@ public class Follower extends AbstractRaftActorBehavior {
         membersToCheck.removeAll(unreachable);
 
         // check if the only member not unreachable is us
-        if (membersToCheck.size() == 1 && membersToCheck.iterator().next().equals(selfMember)) {
-            return true;
-        }
-
-        return false;
+        return membersToCheck.size() == 1 && membersToCheck.iterator().next().equals(selfMember);
     }
 
     private void handleInstallSnapshot(final ActorRef sender, final InstallSnapshot installSnapshot) {
@@ -638,7 +636,7 @@ public class Follower extends AbstractRaftActorBehavior {
 
                 Snapshot snapshot = Snapshot.create(
                         context.getSnapshotManager().convertSnapshot(snapshotTracker.getSnapshotBytes()),
-                        new ArrayList<>(),
+                        List.of(),
                         installSnapshot.getLastIncludedIndex(),
                         installSnapshot.getLastIncludedTerm(),
                         installSnapshot.getLastIncludedIndex(),
@@ -672,8 +670,7 @@ public class Follower extends AbstractRaftActorBehavior {
         } catch (IOException e) {
             log.debug("{}: Exception in InstallSnapshot of follower", logName(), e);
 
-            sender.tell(new InstallSnapshotReply(currentTerm(), context.getId(),
-                    -1, false), actor());
+            sender.tell(new InstallSnapshotReply(currentTerm(), context.getId(), -1, false), actor());
 
             closeSnapshotTracker();
         }