Migrate InstallSnapshot/SnapshotTracker use of Optional
[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / messages / InstallSnapshot.java
index 9d40fa3d9edb3858969797e929776ddcba424333..39fa74bd2294bf2a0940976ceea97734626dd1fc 100644 (file)
@@ -5,25 +5,40 @@
  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
  * and is available at http://www.eclipse.org/legal/epl-v10.html
  */
-
 package org.opendaylight.controller.cluster.raft.messages;
 
-import com.google.protobuf.ByteString;
-import org.opendaylight.controller.cluster.raft.protobuff.messages.InstallSnapshotMessages;
-
+import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
+import java.io.Externalizable;
+import java.io.IOException;
+import java.io.ObjectInput;
+import java.io.ObjectOutput;
+import java.util.Optional;
+import java.util.OptionalInt;
+import org.opendaylight.controller.cluster.raft.persisted.ServerConfigurationPayload;
+
+/**
+ * Message sent from a leader to install a snapshot chunk on a follower.
+ */
 public class InstallSnapshot extends AbstractRaftRPC {
-
-    public static final Class SERIALIZABLE_CLASS = InstallSnapshotMessages.InstallSnapshot.class;
+    private static final long serialVersionUID = 1L;
 
     private final String leaderId;
     private final long lastIncludedIndex;
     private final long lastIncludedTerm;
-    private final ByteString data;
+    private final byte[] data;
     private final int chunkIndex;
     private final int totalChunks;
-
-    public InstallSnapshot(long term, String leaderId, long lastIncludedIndex,
-        long lastIncludedTerm, ByteString data, int chunkIndex, int totalChunks) {
+    @SuppressFBWarnings(value = "SE_BAD_FIELD", justification = "Handled via writeReplace()")
+    private final OptionalInt lastChunkHashCode;
+    @SuppressFBWarnings(value = "SE_BAD_FIELD", justification = "Handled via writeReplace()")
+    private final Optional<ServerConfigurationPayload> serverConfig;
+
+    @SuppressFBWarnings(value = "EI_EXPOSE_REP2", justification = "Stores a reference to an externally mutable byte[] "
+            + "object but this is OK since this class is merely a DTO and does not process byte[] internally. "
+            + "Also it would be inefficient to create a copy as the byte[] could be large.")
+    public InstallSnapshot(final long term, final String leaderId, final long lastIncludedIndex,
+            final long lastIncludedTerm, final byte[] data, final int chunkIndex, final int totalChunks,
+            final OptionalInt lastChunkHashCode, final Optional<ServerConfigurationPayload> serverConfig) {
         super(term);
         this.leaderId = leaderId;
         this.lastIncludedIndex = lastIncludedIndex;
@@ -31,6 +46,15 @@ public class InstallSnapshot extends AbstractRaftRPC {
         this.data = data;
         this.chunkIndex = chunkIndex;
         this.totalChunks = totalChunks;
+        this.lastChunkHashCode = lastChunkHashCode;
+        this.serverConfig = serverConfig;
+    }
+
+    public InstallSnapshot(final long term, final String leaderId, final long lastIncludedIndex,
+                           final long lastIncludedTerm, final byte[] data, final int chunkIndex,
+                           final int totalChunks) {
+        this(term, leaderId, lastIncludedIndex, lastIncludedTerm, data, chunkIndex, totalChunks, OptionalInt.empty(),
+            Optional.empty());
     }
 
     public String getLeaderId() {
@@ -45,7 +69,10 @@ public class InstallSnapshot extends AbstractRaftRPC {
         return lastIncludedTerm;
     }
 
-    public ByteString getData() {
+    @SuppressFBWarnings(value = "EI_EXPOSE_REP", justification = "Exposes a mutable object stored in a field but "
+            + "this is OK since this class is merely a DTO and does not process the byte[] internally. "
+            + "Also it would be inefficient to create a return copy as the byte[] could be large.")
+    public byte[] getData() {
         return data;
     }
 
@@ -57,26 +84,89 @@ public class InstallSnapshot extends AbstractRaftRPC {
         return totalChunks;
     }
 
-    public <T extends Object> Object toSerializable(){
-        return InstallSnapshotMessages.InstallSnapshot.newBuilder()
-            .setLeaderId(this.getLeaderId())
-            .setChunkIndex(this.getChunkIndex())
-            .setData(this.getData())
-            .setLastIncludedIndex(this.getLastIncludedIndex())
-            .setLastIncludedTerm(this.getLastIncludedTerm())
-            .setTotalChunks(this.getTotalChunks()).build();
+    public OptionalInt getLastChunkHashCode() {
+        return lastChunkHashCode;
+    }
+
+    public Optional<ServerConfigurationPayload> getServerConfig() {
+        return serverConfig;
+    }
 
+
+    public <T> Object toSerializable(final short version) {
+        return this;
     }
 
-    public static InstallSnapshot fromSerializable (Object o) {
-        InstallSnapshotMessages.InstallSnapshot from =
-            (InstallSnapshotMessages.InstallSnapshot) o;
+    @Override
+    public String toString() {
+        return "InstallSnapshot [term=" + getTerm() + ", leaderId=" + leaderId + ", lastIncludedIndex="
+                + lastIncludedIndex + ", lastIncludedTerm=" + lastIncludedTerm + ", datasize=" + data.length
+                + ", Chunk=" + chunkIndex + "/" + totalChunks + ", lastChunkHashCode=" + lastChunkHashCode
+                + ", serverConfig=" + serverConfig.orElse(null) + "]";
+    }
 
-        InstallSnapshot installSnapshot = new InstallSnapshot(from.getTerm(),
-            from.getLeaderId(), from.getLastIncludedIndex(),
-            from.getLastIncludedTerm(), from.getData(),
-            from.getChunkIndex(), from.getTotalChunks());
+    private Object writeReplace() {
+        return new Proxy(this);
+    }
 
-        return installSnapshot;
+    private static class Proxy implements Externalizable {
+        private static final long serialVersionUID = 1L;
+
+        private InstallSnapshot installSnapshot;
+
+        // 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() {
+        }
+
+        Proxy(final InstallSnapshot installSnapshot) {
+            this.installSnapshot = installSnapshot;
+        }
+
+        @Override
+        public void writeExternal(final ObjectOutput out) throws IOException {
+            out.writeLong(installSnapshot.getTerm());
+            out.writeObject(installSnapshot.leaderId);
+            out.writeLong(installSnapshot.lastIncludedIndex);
+            out.writeLong(installSnapshot.lastIncludedTerm);
+            out.writeInt(installSnapshot.chunkIndex);
+            out.writeInt(installSnapshot.totalChunks);
+
+            out.writeByte(installSnapshot.lastChunkHashCode.isPresent() ? 1 : 0);
+            if (installSnapshot.lastChunkHashCode.isPresent()) {
+                out.writeInt(installSnapshot.lastChunkHashCode.getAsInt());
+            }
+
+            out.writeByte(installSnapshot.serverConfig.isPresent() ? 1 : 0);
+            if (installSnapshot.serverConfig.isPresent()) {
+                out.writeObject(installSnapshot.serverConfig.get());
+            }
+
+            out.writeObject(installSnapshot.data);
+        }
+
+        @Override
+        public void readExternal(final ObjectInput in) throws IOException, ClassNotFoundException {
+            long term = in.readLong();
+            String leaderId = (String) in.readObject();
+            long lastIncludedIndex = in.readLong();
+            long lastIncludedTerm = in.readLong();
+            int chunkIndex = in.readInt();
+            int totalChunks = in.readInt();
+
+            OptionalInt lastChunkHashCode = in.readByte() == 1 ? OptionalInt.of(in.readInt()) : OptionalInt.empty();
+            Optional<ServerConfigurationPayload> serverConfig = in.readByte() == 1
+                    ? Optional.of((ServerConfigurationPayload)in.readObject()) : Optional.empty();
+
+            byte[] data = (byte[])in.readObject();
+
+            installSnapshot = new InstallSnapshot(term, leaderId, lastIncludedIndex, lastIncludedTerm, data,
+                    chunkIndex, totalChunks, lastChunkHashCode, serverConfig);
+        }
+
+        private Object readResolve() {
+            return installSnapshot;
+        }
     }
 }