ServerInfo should be a plain record

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

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/persisted/Snapshot.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/persisted/Snapshot.java
index aa3500e33a1789ed10ade94f8a3cbc59a23836f7..81d2331bb4b6c9af4b700c9be2b1a2a37f8328da 100644 (file)
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/persisted/Snapshot.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/persisted/Snapshot.java
@@ -7,95 +7,34 @@
  */
 package org.opendaylight.controller.cluster.raft.persisted;
 
-import java.io.Externalizable;
-import java.io.IOException;
-import java.io.ObjectInput;
-import java.io.ObjectOutput;
 import java.io.Serializable;
-import java.util.ArrayList;
 import java.util.List;
 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
-import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
 
 /**
  * Represents a snapshot of the raft data.
  *
  * @author Thomas Pantelis
  */
-public class Snapshot implements Serializable {
-
+public final class Snapshot implements Serializable {
     /**
      * Implementations of this interface are used as the state payload for a snapshot.
      *
      * @author Thomas Pantelis
      */
     public interface State extends Serializable {
-    }
-
-    private static final class Proxy implements Externalizable {
-        private static final long serialVersionUID = 1L;
-
-        private Snapshot snapshot;
-
-        // checkstyle flags the public modifier as redundant which really doesn't make sense since it clearly isn't
-        // redundant. It is explicitly needed for Java serialization to be able to create instances via reflection.
-        @SuppressWarnings("checkstyle:RedundantModifier")
-        public Proxy() {
-            // For Externalizable
-        }
-
-        Proxy(final Snapshot snapshot) {
-            this.snapshot = snapshot;
-        }
-
-        @Override
-        public void writeExternal(final ObjectOutput out) throws IOException {
-            out.writeLong(snapshot.lastIndex);
-            out.writeLong(snapshot.lastTerm);
-            out.writeLong(snapshot.lastAppliedIndex);
-            out.writeLong(snapshot.lastAppliedTerm);
-            out.writeLong(snapshot.electionTerm);
-            out.writeObject(snapshot.electionVotedFor);
-            out.writeObject(snapshot.serverConfig);
-
-            out.writeInt(snapshot.unAppliedEntries.size());
-            for (ReplicatedLogEntry e: snapshot.unAppliedEntries) {
-                out.writeLong(e.getIndex());
-                out.writeLong(e.getTerm());
-                out.writeObject(e.getData());
-            }
-
-            out.writeObject(snapshot.state);
-        }
-
-        @Override
-        public void readExternal(final ObjectInput in) throws IOException, ClassNotFoundException {
-            long lastIndex = in.readLong();
-            long lastTerm = in.readLong();
-            long lastAppliedIndex = in.readLong();
-            long lastAppliedTerm = in.readLong();
-            long electionTerm = in.readLong();
-            String electionVotedFor = (String) in.readObject();
-            ServerConfigurationPayload serverConfig = (ServerConfigurationPayload) in.readObject();
-
-            int size = in.readInt();
-            List<ReplicatedLogEntry> unAppliedEntries = new ArrayList<>(size);
-            for (int i = 0; i < size; i++) {
-                unAppliedEntries.add(new SimpleReplicatedLogEntry(in.readLong(), in.readLong(),
-                        (Payload) in.readObject()));
-            }
-
-            State state = (State) in.readObject();
-
-            snapshot = Snapshot.create(state, unAppliedEntries, lastIndex, lastTerm, lastAppliedIndex, lastAppliedTerm,
-                    electionTerm, electionVotedFor, serverConfig);
-        }
-
-        private Object readResolve() {
-            return snapshot;
+        /**
+         * Indicate whether the snapshot requires migration, i.e. a new snapshot should be created after recovery.
+         * Default implementation returns false, i.e. do not re-snapshot.
+         *
+         * @return True if complete recovery based upon this snapshot should trigger a new snapshot.
+         */
+        default boolean needsMigration() {
+            return false;
         }
     }
 
+    @java.io.Serial
     private static final long serialVersionUID = 1L;
 
     private final State state;
@@ -108,9 +47,9 @@ public class Snapshot implements Serializable {
     private final String electionVotedFor;
     private final ServerConfigurationPayload serverConfig;
 
-    private Snapshot(State state, List<ReplicatedLogEntry> unAppliedEntries, long lastIndex, long lastTerm,
-            long lastAppliedIndex, long lastAppliedTerm, long electionTerm, String electionVotedFor,
-            ServerConfigurationPayload serverConfig) {
+    private Snapshot(final State state, final List<ReplicatedLogEntry> unAppliedEntries, final long lastIndex,
+            final long lastTerm, final long lastAppliedIndex, final long lastAppliedTerm, final long electionTerm,
+            final String electionVotedFor, final ServerConfigurationPayload serverConfig) {
         this.state = state;
         this.unAppliedEntries = unAppliedEntries;
         this.lastIndex = lastIndex;
@@ -122,9 +61,9 @@ public class Snapshot implements Serializable {
         this.serverConfig = serverConfig;
     }
 
-    public static Snapshot create(State state, List<ReplicatedLogEntry> entries, long lastIndex, long lastTerm,
-            long lastAppliedIndex, long lastAppliedTerm, long electionTerm, String electionVotedFor,
-            ServerConfigurationPayload serverConfig) {
+    public static Snapshot create(final State state, final List<ReplicatedLogEntry> entries, final long lastIndex,
+            final long lastTerm, final long lastAppliedIndex, final long lastAppliedTerm, final long electionTerm,
+            final String electionVotedFor, final ServerConfigurationPayload serverConfig) {
         return new Snapshot(state, entries, lastIndex, lastTerm, lastAppliedIndex, lastAppliedTerm,
                 electionTerm, electionVotedFor, serverConfig);
     }
@@ -150,7 +89,7 @@ public class Snapshot implements Serializable {
     }
 
     public long getLastIndex() {
-        return this.lastIndex;
+        return lastIndex;
     }
 
     public long getElectionTerm() {
@@ -165,10 +104,6 @@ public class Snapshot implements Serializable {
         return serverConfig;
     }
 
-    private Object writeReplace() {
-        return new Proxy(this);
-    }
-
     @Override
     public String toString() {
         return "Snapshot [lastIndex=" + lastIndex + ", lastTerm=" + lastTerm + ", lastAppliedIndex=" + lastAppliedIndex
@@ -176,4 +111,9 @@ public class Snapshot implements Serializable {
                 + ", state=" + state + ", electionTerm=" + electionTerm + ", electionVotedFor="
                 + electionVotedFor + ", ServerConfigPayload="  + serverConfig + "]";
     }
+
+    @java.io.Serial
+    private Object writeReplace() {
+        return new SS(this);
+    }
 }