Do not leak DataTree from backend actor

[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / databroker / actors / dds / SimpleShardBackendResolver.java

diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/SimpleShardBackendResolver.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/SimpleShardBackendResolver.java
index 056a1ea7e226deb49a6ee12e916769bf7e6dbb0c..012e068a81bcbb23fba18f8163057d744b0f0d6c 100644 (file)
--- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/SimpleShardBackendResolver.java
+++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/databroker/actors/dds/SimpleShardBackendResolver.java
@@ -7,23 +7,24 @@
  */
 package org.opendaylight.controller.cluster.databroker.actors.dds;
 
-import com.google.common.base.Preconditions;
+import static com.google.common.base.Preconditions.checkArgument;
+import static java.util.Objects.requireNonNull;
+
 import java.util.concurrent.CompletionStage;
-import javax.annotation.concurrent.ThreadSafe;
 import org.opendaylight.controller.cluster.access.client.BackendInfoResolver;
 import org.opendaylight.controller.cluster.access.concepts.ClientIdentifier;
-import org.opendaylight.controller.cluster.datastore.utils.ActorContext;
+import org.opendaylight.controller.cluster.datastore.utils.ActorUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 /**
  * {@link BackendInfoResolver} implementation for static shard configuration based on ShardManager. Unlike the full
  * {@link ModuleShardBackendResolver}, this resolver is used in situations where the client corresponds exactly to one
- * backend shard, e.g. there is only one fixed cookie assigned and the operation path is not consulted at all.
+ * backend shard, e.g. there is only one fixed cookie assigned and the operation path is not consulted at all. This
+ * class is thread-safe.
  *
  * @author Robert Varga
  */
-@ThreadSafe
 final class SimpleShardBackendResolver extends AbstractShardBackendResolver {
     private static final Logger LOG = LoggerFactory.getLogger(SimpleShardBackendResolver.class);
 
@@ -32,27 +33,42 @@ final class SimpleShardBackendResolver extends AbstractShardBackendResolver {
     private volatile ShardState state;
 
     // FIXME: we really need just ActorContext.findPrimaryShardAsync()
-    SimpleShardBackendResolver(final ClientIdentifier clientId, final ActorContext actorContext,
+    SimpleShardBackendResolver(final ClientIdentifier clientId, final ActorUtils actorUtils,
             final String shardName) {
-        super(clientId, actorContext);
-        this.shardName = Preconditions.checkNotNull(shardName);
+        super(clientId, actorUtils);
+        this.shardName = requireNonNull(shardName);
     }
 
     private CompletionStage<ShardBackendInfo> getBackendInfo(final long cookie) {
-        Preconditions.checkArgument(cookie == 0);
+        checkArgument(cookie == 0);
 
-        ShardState local = state;
-        if (local == null) {
-            synchronized (this) {
-                local = state;
-                if (local == null) {
-                    local = resolveBackendInfo(shardName, 0);
-                    state = local;
-                }
-            }
+        final ShardState existing = state;
+        if (existing != null) {
+            return existing.getStage();
         }
 
-        return local.getStage();
+        synchronized (this) {
+            final ShardState recheck = state;
+            if (recheck != null) {
+                return recheck.getStage();
+            }
+
+            final ShardState newState = resolveBackendInfo(shardName, 0);
+            state = newState;
+
+            final CompletionStage<ShardBackendInfo> stage = newState.getStage();
+            stage.whenComplete((info, failure) -> {
+                if (failure != null) {
+                    synchronized (SimpleShardBackendResolver.this) {
+                        if (state == newState) {
+                            state = null;
+                        }
+                    }
+                }
+            });
+
+            return stage;
+        }
     }
 
     @Override
@@ -73,11 +89,16 @@ final class SimpleShardBackendResolver extends AbstractShardBackendResolver {
             synchronized (this) {
                 LOG.debug("Invalidating backend information {}", staleInfo);
                 flushCache(shardName);
-                LOG.trace("Invalidated cache %s", staleInfo);
+                LOG.trace("Invalidated cache {}", staleInfo);
                 state = null;
             }
         }
 
         return getBackendInfo(cookie);
     }
+
+    @Override
+    public String resolveCookieName(Long cookie) {
+        return shardName;
+    }
 }