Fix checkstyle whitespace issues - WHITESPACE ONLY

Change-Id: Ic205c1afd639c6008d61d9de95cb764eeb6238ca
diff --git a/src/main/java/net/onrc/onos/core/topology/INetworkGraphService.java b/src/main/java/net/onrc/onos/core/topology/INetworkGraphService.java
index 9d4cb3a..18eb785 100644
--- a/src/main/java/net/onrc/onos/core/topology/INetworkGraphService.java
+++ b/src/main/java/net/onrc/onos/core/topology/INetworkGraphService.java
@@ -6,13 +6,15 @@
  * Interface for providing the Network Graph Service to other modules.
  */
 public interface INetworkGraphService extends IFloodlightService {
-	/**
-	 * Allows a module to get a reference to the global network graph object.
-	 * @return
-	 */
+    /**
+     * Allows a module to get a reference to the global network graph object.
+     *
+     * @return
+     */
     public NetworkGraph getNetworkGraph();
 
     public void registerNetworkGraphListener(INetworkGraphListener listener);
+
     public void deregisterNetworkGraphListener(INetworkGraphListener listener);
 
     /**
@@ -20,6 +22,7 @@
      * the network graph.
      * TODO Figure out how to hide the southbound interface from
      * applications/modules that shouldn't touch it
+     *
      * @return
      */
     public NetworkGraphDiscoveryInterface getNetworkGraphDiscoveryInterface();