[ONOS-4612]Update SFC flows inline with the Official OVS NSH patch

Change-Id: If58517841096a939860d88aa78eca7cae46b9935
diff --git a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/ServiceFunctionCodec.java b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/ServiceFunctionCodec.java
new file mode 100644
index 0000000..f847b10
--- /dev/null
+++ b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/web/ServiceFunctionCodec.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.vtnweb.web;
+
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.vtnrsc.ServiceFunctionGroup;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+
+/**
+ * Service function JSON codec.
+ */
+public final class ServiceFunctionCodec extends JsonCodec<ServiceFunctionGroup> {
+
+    private static final String NAME = "name";
+    private static final String DESCRIPTION = "description";
+    private static final String PORT_PAIR_LOAD = "port_pair_load";
+    @Override
+    public ObjectNode encode(ServiceFunctionGroup serviceFunction, CodecContext context) {
+        checkNotNull(serviceFunction, "service cannot be null");
+        ObjectNode result = context.mapper().createObjectNode()
+                .put(NAME, serviceFunction.name())
+                .put(DESCRIPTION, serviceFunction.description())
+                .put(PORT_PAIR_LOAD, serviceFunction.portPairLoadMap().toString());
+        return result;
+    }
+}