Distributed group store using eventual consistent map abstraction

Change-Id: I618a0f6fa80e0e25285d7a2026032f09ba90aa70
diff --git a/core/api/src/main/java/org/onosproject/net/group/GroupStore.java b/core/api/src/main/java/org/onosproject/net/group/GroupStore.java
index e7bf4f8..7ccab8a 100644
--- a/core/api/src/main/java/org/onosproject/net/group/GroupStore.java
+++ b/core/api/src/main/java/org/onosproject/net/group/GroupStore.java
@@ -15,6 +15,7 @@
  */
 package org.onosproject.net.group;
 
+import org.onosproject.core.GroupId;
 import org.onosproject.net.DeviceId;
 import org.onosproject.store.Store;
 
@@ -60,6 +61,15 @@
     Group getGroup(DeviceId deviceId, GroupKey appCookie);
 
     /**
+     * Returns the stored group entry for an id.
+     *
+     * @param deviceId the device ID
+     * @param groupId the group identifier
+     * @return a group associated with the key
+     */
+    Group getGroup(DeviceId deviceId, GroupId groupId);
+
+    /**
      * Stores a new group entry using the information from group description.
      *
      * @param groupDesc group description to be used to store group entry