Fixed equals methods for better efficiency.
Cleaned up ClusterService API.
diff --git a/core/api/src/main/java/org/onlab/onos/net/topology/DefaultTopologyEdge.java b/core/api/src/main/java/org/onlab/onos/net/topology/DefaultTopologyEdge.java
index 00eb3d2..c399f3c 100644
--- a/core/api/src/main/java/org/onlab/onos/net/topology/DefaultTopologyEdge.java
+++ b/core/api/src/main/java/org/onlab/onos/net/topology/DefaultTopologyEdge.java
@@ -50,6 +50,9 @@
 
     @Override
     public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
         if (obj instanceof DefaultTopologyEdge) {
             final DefaultTopologyEdge other = (DefaultTopologyEdge) obj;
             return Objects.equals(this.link, other.link);