Fix findbugs warnings
[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / RaftActorRecoverySupport.java
index 15d98b5289d1db98050e1f956dbf8a4859830d4e..f071d945662a73d22803fc9ea277a88d88ef29c1 100644 (file)
@@ -10,18 +10,19 @@ package org.opendaylight.controller.cluster.raft;
 import akka.persistence.RecoveryCompleted;
 import akka.persistence.SnapshotOffer;
 import com.google.common.base.Stopwatch;
-import java.io.ByteArrayInputStream;
-import java.io.ObjectInputStream;
 import java.util.Collections;
 import org.opendaylight.controller.cluster.PersistentDataProvider;
 import org.opendaylight.controller.cluster.raft.base.messages.ApplySnapshot;
 import org.opendaylight.controller.cluster.raft.persisted.ApplyJournalEntries;
 import org.opendaylight.controller.cluster.raft.persisted.DeleteEntries;
+import org.opendaylight.controller.cluster.raft.persisted.EmptyState;
 import org.opendaylight.controller.cluster.raft.persisted.MigratedSerializable;
 import org.opendaylight.controller.cluster.raft.persisted.ServerConfigurationPayload;
+import org.opendaylight.controller.cluster.raft.persisted.Snapshot;
 import org.opendaylight.controller.cluster.raft.persisted.UpdateElectionTerm;
 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.PersistentPayload;
 import org.slf4j.Logger;
+
 /**
  * Support class that handles persistence recovery for a RaftActor.
  *
@@ -45,12 +46,12 @@ class RaftActorRecoverySupport {
         this.log = context.getLogger();
     }
 
-    boolean handleRecoveryMessage(Object message, PersistentDataProvider persistentProvider) {
+    boolean handleRecoveryMessage(final Object message, final PersistentDataProvider persistentProvider) {
         log.trace("{}: handleRecoveryMessage: {}", context.getId(), message);
 
         anyDataRecovered = anyDataRecovered || !(message instanceof RecoveryCompleted);
 
-        if(isMigratedSerializable(message)) {
+        if (isMigratedSerializable(message)) {
             hasMigratedDataRecovered = true;
         }
 
@@ -76,27 +77,22 @@ class RaftActorRecoverySupport {
         return recoveryComplete;
     }
 
+    @SuppressWarnings("checkstyle:IllegalCatch")
     private void possiblyRestoreFromSnapshot() {
-        byte[] restoreFromSnapshot = cohort.getRestoreFromSnapshot();
-        if(restoreFromSnapshot == null) {
+        Snapshot restoreFromSnapshot = cohort.getRestoreFromSnapshot();
+        if (restoreFromSnapshot == null) {
             return;
         }
 
-        if(anyDataRecovered) {
+        if (anyDataRecovered) {
             log.warn("{}: The provided restore snapshot was not applied because the persistence store is not empty",
                     context.getId());
             return;
         }
 
-        try(ObjectInputStream ois = new ObjectInputStream(new ByteArrayInputStream(restoreFromSnapshot))) {
-            Snapshot snapshot = (Snapshot) ois.readObject();
-
-            log.debug("{}: Deserialized restore snapshot: {}", context.getId(), snapshot);
+        log.debug("{}: Restore snapshot: {}", context.getId(), restoreFromSnapshot);
 
-            context.getSnapshotManager().apply(new ApplySnapshot(snapshot));
-        } catch(Exception e) {
-            log.error("{}: Error deserializing snapshot restore", context.getId(), e);
-        }
+        context.getSnapshotManager().apply(new ApplySnapshot(restoreFromSnapshot));
     }
 
     private ReplicatedLog replicatedLog() {
@@ -104,31 +100,30 @@ class RaftActorRecoverySupport {
     }
 
     private void initRecoveryTimer() {
-        if(recoveryTimer == null) {
+        if (recoveryTimer == null) {
             recoveryTimer = Stopwatch.createStarted();
         }
     }
 
-    private void onRecoveredSnapshot(SnapshotOffer offer) {
-        if(log.isDebugEnabled()) {
-            log.debug("{}: SnapshotOffer called..", context.getId());
-        }
+    private void onRecoveredSnapshot(final SnapshotOffer offer) {
+        log.debug("{}: SnapshotOffer called.", context.getId());
 
         initRecoveryTimer();
 
         Snapshot snapshot = (Snapshot) offer.snapshot();
 
-        for(ReplicatedLogEntry entry: snapshot.getUnAppliedEntries()) {
-            if(isMigratedPayload(entry)) {
+        for (ReplicatedLogEntry entry: snapshot.getUnAppliedEntries()) {
+            if (isMigratedPayload(entry)) {
                 hasMigratedDataRecovered = true;
             }
         }
 
-        if(!context.getPersistenceProvider().isRecoveryApplicable()) {
+        if (!context.getPersistenceProvider().isRecoveryApplicable()) {
             // We may have just transitioned to disabled and have a snapshot containing state data and/or log
             // entries - we don't want to preserve these, only the server config and election term info.
 
-            snapshot = Snapshot.create(new byte[0], Collections.emptyList(), -1, -1, -1, -1,
+            snapshot = Snapshot.create(
+                    EmptyState.INSTANCE, Collections.emptyList(), -1, -1, -1, -1,
                     snapshot.getElectionTerm(), snapshot.getElectionVotedFor(), snapshot.getServerConfiguration());
         }
 
@@ -144,14 +139,12 @@ class RaftActorRecoverySupport {
         Stopwatch timer = Stopwatch.createStarted();
 
         // Apply the snapshot to the actors state
-        cohort.applyRecoverySnapshot(snapshot.getState());
+        if (!(snapshot.getState() instanceof EmptyState)) {
+            cohort.applyRecoverySnapshot(snapshot.getState());
+        }
 
         if (snapshot.getServerConfiguration() != null) {
             context.updatePeerIds(snapshot.getServerConfiguration());
-
-            if(isMigratedSerializable(snapshot.getServerConfiguration())) {
-                hasMigratedDataRecovered = true;
-            }
         }
 
         timer.stop();
@@ -160,36 +153,36 @@ class RaftActorRecoverySupport {
                 replicatedLog().getSnapshotTerm(), replicatedLog().size());
     }
 
-    private void onRecoveredJournalLogEntry(ReplicatedLogEntry logEntry) {
-        if(log.isDebugEnabled()) {
+    private void onRecoveredJournalLogEntry(final ReplicatedLogEntry logEntry) {
+        if (log.isDebugEnabled()) {
             log.debug("{}: Received ReplicatedLogEntry for recovery: index: {}, size: {}", context.getId(),
                     logEntry.getIndex(), logEntry.size());
         }
 
-        if(isServerConfigurationPayload(logEntry)){
+        if (isServerConfigurationPayload(logEntry)) {
             context.updatePeerIds((ServerConfigurationPayload)logEntry.getData());
         }
 
-        if(isMigratedPayload(logEntry)) {
+        if (isMigratedPayload(logEntry)) {
             hasMigratedDataRecovered = true;
         }
 
-        if(context.getPersistenceProvider().isRecoveryApplicable()) {
+        if (context.getPersistenceProvider().isRecoveryApplicable()) {
             replicatedLog().append(logEntry);
-        } else if(!isPersistentPayload(logEntry)) {
+        } else if (!isPersistentPayload(logEntry)) {
             dataRecoveredWithPersistenceDisabled = true;
         }
     }
 
-    private void onRecoveredApplyLogEntries(long toIndex) {
-        if(!context.getPersistenceProvider().isRecoveryApplicable()) {
+    private void onRecoveredApplyLogEntries(final long toIndex) {
+        if (!context.getPersistenceProvider().isRecoveryApplicable()) {
             dataRecoveredWithPersistenceDisabled = true;
             return;
         }
 
         long lastUnappliedIndex = context.getLastApplied() + 1;
 
-        if(log.isDebugEnabled()) {
+        if (log.isDebugEnabled()) {
             // it can happen that lastUnappliedIndex > toIndex, if the AJE is in the persistent journal
             // but the entry itself has made it to that state and recovered via the snapshot
             log.debug("{}: Received apply journal entries for recovery, applying to state: {} to {}",
@@ -199,7 +192,7 @@ class RaftActorRecoverySupport {
         long lastApplied = lastUnappliedIndex - 1;
         for (long i = lastUnappliedIndex; i <= toIndex; i++) {
             ReplicatedLogEntry logEntry = replicatedLog().get(i);
-            if(logEntry != null) {
+            if (logEntry != null) {
                 lastApplied++;
                 batchRecoveredLogEntry(logEntry);
             } else {
@@ -213,26 +206,26 @@ class RaftActorRecoverySupport {
         context.setCommitIndex(lastApplied);
     }
 
-    private void onDeleteEntries(DeleteEntries deleteEntries) {
-        if(context.getPersistenceProvider().isRecoveryApplicable()) {
+    private void onDeleteEntries(final DeleteEntries deleteEntries) {
+        if (context.getPersistenceProvider().isRecoveryApplicable()) {
             replicatedLog().removeFrom(deleteEntries.getFromIndex());
         } else {
             dataRecoveredWithPersistenceDisabled = true;
         }
     }
 
-    private void batchRecoveredLogEntry(ReplicatedLogEntry logEntry) {
+    private void batchRecoveredLogEntry(final ReplicatedLogEntry logEntry) {
         initRecoveryTimer();
 
         int batchSize = context.getConfigParams().getJournalRecoveryLogBatchSize();
-        if(!isServerConfigurationPayload(logEntry)){
-            if(currentRecoveryBatchCount == 0) {
+        if (!isServerConfigurationPayload(logEntry)) {
+            if (currentRecoveryBatchCount == 0) {
                 cohort.startLogRecoveryBatch(batchSize);
             }
 
             cohort.appendRecoveredLogEntry(logEntry.getData());
 
-            if(++currentRecoveryBatchCount >= batchSize) {
+            if (++currentRecoveryBatchCount >= batchSize) {
                 endCurrentLogRecoveryBatch();
             }
         }
@@ -243,27 +236,26 @@ class RaftActorRecoverySupport {
         currentRecoveryBatchCount = 0;
     }
 
-    private void onRecoveryCompletedMessage(PersistentDataProvider persistentProvider) {
-        if(currentRecoveryBatchCount > 0) {
+    private void onRecoveryCompletedMessage(final PersistentDataProvider persistentProvider) {
+        if (currentRecoveryBatchCount > 0) {
             endCurrentLogRecoveryBatch();
         }
 
         String recoveryTime = "";
-        if(recoveryTimer != null) {
+        if (recoveryTimer != null) {
             recoveryTimer.stop();
             recoveryTime = " in " + recoveryTimer.toString();
             recoveryTimer = null;
         }
 
-        log.info("Recovery completed" + recoveryTime + " - Switching actor to Follower - " +
-                 "Persistence Id =  " + context.getId() +
-                 " Last index in log = {}, snapshotIndex = {}, snapshotTerm = {}, " +
-                 "journal-size = {}", replicatedLog().lastIndex(), replicatedLog().getSnapshotIndex(),
+        log.info("Recovery completed {} - Switching actor to Follower - Persistence Id = {}"
+                 + " Last index in log = {}, snapshotIndex = {}, snapshotTerm = {}, journal-size = {}",
+                 recoveryTime, context.getId(), replicatedLog().lastIndex(), replicatedLog().getSnapshotIndex(),
                  replicatedLog().getSnapshotTerm(), replicatedLog().size());
 
-        if(dataRecoveredWithPersistenceDisabled ||
-                hasMigratedDataRecovered && !context.getPersistenceProvider().isRecoveryApplicable()) {
-            if(hasMigratedDataRecovered) {
+        if (dataRecoveredWithPersistenceDisabled
+                || hasMigratedDataRecovered && !context.getPersistenceProvider().isRecoveryApplicable()) {
+            if (hasMigratedDataRecovered) {
                 log.info("{}: Saving snapshot after recovery due to migrated messages", context.getId());
             } else {
                 log.info("{}: Saving snapshot after recovery due to data persistence disabled", context.getId());
@@ -274,14 +266,16 @@ class RaftActorRecoverySupport {
             // messages. Either way, we persist a snapshot and delete all the messages from the akka journal
             // to clean out unwanted messages.
 
-            Snapshot snapshot = Snapshot.create(new byte[0], Collections.<ReplicatedLogEntry>emptyList(), -1, -1, -1, -1,
+            Snapshot snapshot = Snapshot.create(
+                    EmptyState.INSTANCE, Collections.<ReplicatedLogEntry>emptyList(),
+                    -1, -1, -1, -1,
                     context.getTermInformation().getCurrentTerm(), context.getTermInformation().getVotedFor(),
                     context.getPeerServerInfo(true));
 
             persistentProvider.saveSnapshot(snapshot);
 
             persistentProvider.deleteMessages(persistentProvider.getLastSequenceNumber());
-        } else if(hasMigratedDataRecovered) {
+        } else if (hasMigratedDataRecovered) {
             log.info("{}: Snapshot capture initiated after recovery due to migrated messages", context.getId());
 
             context.getSnapshotManager().capture(replicatedLog().last(), -1);
@@ -290,19 +284,19 @@ class RaftActorRecoverySupport {
         }
     }
 
-    private static boolean isServerConfigurationPayload(ReplicatedLogEntry repLogEntry){
+    private static boolean isServerConfigurationPayload(final ReplicatedLogEntry repLogEntry) {
         return repLogEntry.getData() instanceof ServerConfigurationPayload;
     }
 
-    private static boolean isPersistentPayload(ReplicatedLogEntry repLogEntry){
+    private static boolean isPersistentPayload(final ReplicatedLogEntry repLogEntry) {
         return repLogEntry.getData() instanceof PersistentPayload;
     }
 
-    private static boolean isMigratedPayload(ReplicatedLogEntry repLogEntry){
+    private static boolean isMigratedPayload(final ReplicatedLogEntry repLogEntry) {
         return isMigratedSerializable(repLogEntry.getData());
     }
 
-    private static boolean isMigratedSerializable(Object message){
+    private static boolean isMigratedSerializable(final Object message) {
         return message instanceof MigratedSerializable && ((MigratedSerializable)message).isMigrated();
     }
 }