Split out TransactionContext classes
[controller.git] / opendaylight / md-sal / sal-distributed-datastore / src / main / java / org / opendaylight / controller / cluster / datastore / DataChangeListener.java
index ba09d0402530921667915eae11103302cfcfb2ea..1bc835f1e3c6883196d4a9a6b1f334bb16f9dca7 100644 (file)
@@ -9,22 +9,90 @@
 package org.opendaylight.controller.cluster.datastore;
 
 import akka.actor.Props;
-import akka.actor.UntypedActor;
 import akka.japi.Creator;
+import com.google.common.base.Preconditions;
+import org.opendaylight.controller.cluster.common.actor.AbstractUntypedActor;
+import org.opendaylight.controller.cluster.datastore.messages.DataChanged;
+import org.opendaylight.controller.cluster.datastore.messages.DataChangedReply;
+import org.opendaylight.controller.cluster.datastore.messages.EnableNotification;
+import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeEvent;
+import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
-public class DataChangeListener extends UntypedActor {
-    @Override public void onReceive(Object message) throws Exception {
-        throw new UnsupportedOperationException("onReceive");
+public class DataChangeListener extends AbstractUntypedActor {
+    private static final Logger LOG = LoggerFactory.getLogger(DataChangeListener.class);
+
+    private final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener;
+    private boolean notificationsEnabled = false;
+
+    public DataChangeListener(AsyncDataChangeListener<YangInstanceIdentifier,
+                                                      NormalizedNode<?, ?>> listener) {
+        this.listener = Preconditions.checkNotNull(listener, "listener should not be null");
+    }
+
+    @Override
+    public void handleReceive(Object message) throws Exception {
+        if(message instanceof DataChanged){
+            dataChanged(message);
+        } else if(message instanceof EnableNotification){
+            enableNotification((EnableNotification) message);
+        }
+    }
+
+    private void enableNotification(EnableNotification message) {
+        notificationsEnabled = message.isEnabled();
+        LOG.debug("{} notifications for listener {}", (notificationsEnabled ? "Enabled" : "Disabled"),
+                listener);
+    }
+
+    private void dataChanged(Object message) {
+
+        // Do nothing if notifications are not enabled
+        if(!notificationsEnabled) {
+            LOG.debug("Notifications not enabled for listener {} - dropping change notification",
+                    listener);
+            return;
+        }
+
+        DataChanged reply = (DataChanged) message;
+        AsyncDataChangeEvent<YangInstanceIdentifier, NormalizedNode<?, ?>> change = reply.getChange();
+
+        LOG.debug("Sending change notification {} to listener {}", change, listener);
+
+        try {
+            this.listener.onDataChanged(change);
+        } catch (RuntimeException e) {
+            LOG.error( String.format( "Error notifying listener %s", this.listener ), e );
+        }
+
+        // It seems the sender is never null but it doesn't hurt to check. If the caller passes in
+        // a null sender (ActorRef.noSender()), akka translates that to the deadLetters actor.
+        if(getSender() != null && !getContext().system().deadLetters().equals(getSender())) {
+            getSender().tell(DataChangedReply.INSTANCE, getSelf());
+        }
+    }
+
+    public static Props props(final AsyncDataChangeListener<YangInstanceIdentifier,
+                                                            NormalizedNode<?, ?>> listener) {
+        return Props.create(new DataChangeListenerCreator(listener));
     }
 
-    public static Props props() {
-        return Props.create(new Creator<DataChangeListener>() {
-            @Override
-            public DataChangeListener create() throws Exception {
-                return new DataChangeListener();
-            }
+    private static class DataChangeListenerCreator implements Creator<DataChangeListener> {
+        private static final long serialVersionUID = 1L;
+
+        final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener;
 
-        });
+        DataChangeListenerCreator(
+                AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener) {
+            this.listener = listener;
+        }
 
+        @Override
+        public DataChangeListener create() throws Exception {
+            return new DataChangeListener(listener);
+        }
     }
 }