[ONOS-3116] port-pair-id testcase

Change-Id: Iad03f6447502d1a363fe56770445554b59b972f2
diff --git a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/PortPairCodec.java b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/PortPairCodec.java
index 7017148..691536f 100644
--- a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/PortPairCodec.java
+++ b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/PortPairCodec.java
@@ -54,7 +54,7 @@
 
         String id = nullIsIllegal(json.get(ID),
                                   ID + MISSING_MEMBER_MESSAGE).asText();
-        resultBuilder.setId(PortPairId.portPairId(id));
+        resultBuilder.setId(PortPairId.of(id));
 
         String tenantId = nullIsIllegal(json.get(TENANT_ID),
                                         TENANT_ID + MISSING_MEMBER_MESSAGE).asText();