Merge pull request #12 from y-higuchi/RAMCloud-yoshi

bugfix
diff --git a/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowEventHandler.java b/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowEventHandler.java
index 17b125a..340bbd8 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowEventHandler.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/flowmanager/FlowEventHandler.java
@@ -156,9 +156,9 @@
 	if (refreshTopology) {
 		refreshTopologyTimer = new Timer();
 		refreshTopologyTimer.schedule(new TimerTask() {
-			private PerfMon pm = PerfMon.getInstance();
 			@Override
 			public void run() {
+				PerfMon pm = PerfMon.getInstance();
 				log.debug("[BEFORE] {}", topology.toString());
 				long begin, end;
 				synchronized(topology) {