PtToPtIntentVirtualNetworkProvider invalid null parameter exception handling.

Change-Id: I2b92da94a6ede704f9372b3f381fc4d97ddd7713
diff --git a/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/PtToPtIntentVirtualNetworkProvider.java b/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/PtToPtIntentVirtualNetworkProvider.java
index d879f59..7cd09ae 100644
--- a/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/PtToPtIntentVirtualNetworkProvider.java
+++ b/incubator/net/src/main/java/org/onosproject/incubator/net/virtual/impl/PtToPtIntentVirtualNetworkProvider.java
@@ -102,9 +102,9 @@
 
     @Override
     public TunnelId createTunnel(NetworkId networkId, ConnectPoint src, ConnectPoint dst) {
-        checkNotNull(NETWORK_ID_NULL, networkId);
-        checkNotNull(CONNECT_POINT_NULL, src);
-        checkNotNull(CONNECT_POINT_NULL, dst);
+        checkNotNull(networkId, NETWORK_ID_NULL);
+        checkNotNull(src, CONNECT_POINT_NULL);
+        checkNotNull(dst, CONNECT_POINT_NULL);
         String key = String.format(KEY_FORMAT, networkId.toString(), src.toString(), dst.toString());
         Key intentKey = Key.of(key, appId);