Enforce to use unique group Id for k8s svc IP, port, proto combination

Change-Id: I6cad3b9ffac86ee0818e6317443c80f5791a9e74
diff --git a/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/util/RulePopulatorUtil.java b/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/util/RulePopulatorUtil.java
index 7605a5e..25a44ea 100644
--- a/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/util/RulePopulatorUtil.java
+++ b/apps/k8s-networking/app/src/main/java/org/onosproject/k8snetworking/util/RulePopulatorUtil.java
@@ -39,6 +39,8 @@
 import java.util.ArrayList;
 import java.util.List;
 
+import static org.onosproject.k8snetworking.api.Constants.DST;
+import static org.onosproject.k8snetworking.api.Constants.SRC;
 import static org.onosproject.net.flow.instructions.ExtensionTreatmentType.ExtensionTreatmentTypes.NICIRA_LOAD;
 import static org.onosproject.net.flow.instructions.ExtensionTreatmentType.ExtensionTreatmentTypes.NICIRA_RESUBMIT_TABLE;
 import static org.onosproject.net.flow.instructions.ExtensionTreatmentType.ExtensionTreatmentTypes.NICIRA_SET_TUNNEL_DST;
@@ -93,9 +95,6 @@
     private static final int SRC_IP = 0x00000e04;
     private static final int DST_IP = 0x00001004;
 
-    private static final String SRC = "src";
-    private static final String DST = "dst";
-
     private static final int OFF_SET_BIT = 16;
     private static final int REMAINDER_BIT = 16;