Expose IMap as short term hack.

- Need a listenable Map for state monitoring.
  We'll need to define subset of IMap interface in the future,
  but as a short term hack to get works done for this iteration
  directly exposing IMap interface for now.
  As part of refactoring after this iteration, we'll define
  our own interface and proxy class to IMap.
- Dummy to use for testing, if we need actual functional HZ.

Change-Id: I88a3f0113eb9db08d1d055bea64c0469070b8e17
diff --git a/src/main/java/net/onrc/onos/core/datagrid/ISharedCollectionsService.java b/src/main/java/net/onrc/onos/core/datagrid/ISharedCollectionsService.java
index 30e5596..a398635 100644
--- a/src/main/java/net/onrc/onos/core/datagrid/ISharedCollectionsService.java
+++ b/src/main/java/net/onrc/onos/core/datagrid/ISharedCollectionsService.java
@@ -1,7 +1,7 @@
 package net.onrc.onos.core.datagrid;
 
 import java.util.concurrent.BlockingQueue;
-import java.util.concurrent.ConcurrentMap;
+import com.hazelcast.core.IMap;
 
 import net.floodlightcontroller.core.module.IFloodlightService;
 
@@ -9,6 +9,8 @@
  * Interface for providing shared maps and queues to other modules.
  */
 public interface ISharedCollectionsService extends IFloodlightService {
+
+    // FIXME Refactor and change IMap to interface defined by us later.
     /**
      * Create an shared, concurrent map.
      *
@@ -17,7 +19,7 @@
      * @param typeV the type of the Value in the map.
      * @return the shared map for the channel name.
      */
-    <K, V> ConcurrentMap<K, V> getConcurrentMap(String mapName,
+    <K, V> IMap<K, V> getConcurrentMap(String mapName,
             Class<K> typeK, Class<V> typeV);
 
     /**