Support for a distributed queue primitive.

Change-Id: I13abb93ec1703105ff0137e137738483a5b6a143
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseState.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseState.java
index 73eacdd..0af7f42 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseState.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DatabaseState.java
@@ -21,6 +21,7 @@
 import java.util.Map.Entry;
 import java.util.Set;
 
+import org.onosproject.cluster.NodeId;
 import org.onosproject.store.service.Transaction;
 import org.onosproject.store.service.Versioned;
 
@@ -113,6 +114,18 @@
   Long counterGetAndAdd(String counterName, long delta);
 
   @Query
+  Long queueSize(String queueName);
+
+  @Query
+  byte[] queuePeek(String queueName);
+
+  @Command
+  byte[] queuePop(String queueName, NodeId requestor);
+
+  @Command
+  Set<NodeId> queuePush(String queueName, byte[] entry);
+
+  @Query
   Long counterGet(String counterName);
 
   @Command