X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsal-distributed-datastore%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fcluster%2Fdatastore%2Fpersisted%2FShardDataTreeSnapshotMetadata.java;h=98302ee503710f9a95cf75b31f69bea6dc5ceefd;hb=55a9b9f42a14c56060f74b38f84d444c0fbfecc4;hp=a20ec4eba4e04461e30a30f1b470076dd2591a7b;hpb=b70b396725749d3fd6ca761f02f4b630f6f4f1ce;p=controller.git

diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/persisted/ShardDataTreeSnapshotMetadata.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/persisted/ShardDataTreeSnapshotMetadata.java
index a20ec4eba4..98302ee503 100644
--- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/persisted/ShardDataTreeSnapshotMetadata.java
+++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/persisted/ShardDataTreeSnapshotMetadata.java
@@ -7,26 +7,31 @@
  */
 package org.opendaylight.controller.cluster.datastore.persisted;
 
-import com.google.common.base.Verify;
+import static com.google.common.base.Verify.verifyNotNull;
+
 import java.io.Externalizable;
 import java.io.Serializable;
-import javax.annotation.Nonnull;
+import org.eclipse.jdt.annotation.NonNull;
 
 /**
  * Base class for various bits of metadata attached to a {@link MetadataShardDataTreeSnapshot}. This class is not
  * an interface because we want to make sure all subclasses implement the externalizable proxy pattern, for which
- * we need to force {@link #readResolve()} to be abstract.
+ * we need to force {@link #writeReplace()} to be abstract. We do that by making it final and exposing a protected
+ * {@link #externalizableProxy()} method.
  *
+ * <p>
  * All concrete subclasses of this class should be final so as to form a distinct set of possible metadata. Since
  * metadata is serialized along with {@link MetadataShardDataTreeSnapshot}, this set is part of the serialization format
  * guarded by {@link PayloadVersion}.
  *
+ * <p>
  * If a new metadata type is introduced or a type is removed, {@link PayloadVersion} needs to be bumped to ensure
  * compatibility.
  *
  * @author Robert Varga
  */
-public abstract class ShardDataTreeSnapshotMetadata implements Serializable {
+public abstract class ShardDataTreeSnapshotMetadata<T extends ShardDataTreeSnapshotMetadata<T>>
+        implements Serializable {
     private static final long serialVersionUID = 1L;
 
     ShardDataTreeSnapshotMetadata() {
@@ -34,13 +39,15 @@ public abstract class ShardDataTreeSnapshotMetadata implements Serializable {
     }
 
     final Object writeReplace() {
-        return Verify.verifyNotNull(externalizableProxy(), "Null externalizable proxy from %s", getClass());
+        return verifyNotNull(externalizableProxy(), "Null externalizable proxy from %s", getClass());
     }
 
     /**
-     * Return an Externalizable proxy
+     * Return an Externalizable proxy.
      *
      * @return Externalizable proxy, may not be null
      */
-    protected abstract @Nonnull Externalizable externalizableProxy();
+    protected abstract @NonNull Externalizable externalizableProxy();
+
+    public abstract Class<T> getType();
 }