Supports dpdk config in OpenstackNode.

Change-Id: I332d7643acb56c5fa7460edb6e4c90a2d862706f
diff --git a/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/codec/DpdkInterfaceCodec.java b/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/codec/DpdkInterfaceCodec.java
new file mode 100644
index 0000000..033bfc0
--- /dev/null
+++ b/apps/openstacknode/app/src/main/java/org/onosproject/openstacknode/codec/DpdkInterfaceCodec.java
@@ -0,0 +1,90 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * 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.openstacknode.codec;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.openstacknode.api.DpdkInterface;
+import org.onosproject.openstacknode.api.DpdkInterface.Type;
+import org.onosproject.openstacknode.impl.DefaultDpdkInterface;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.onlab.util.Tools.nullIsIllegal;
+
+/**
+ * DPDK interface codec used for serializing and de-serializing JSON string.
+ */
+public class DpdkInterfaceCodec extends JsonCodec<DpdkInterface> {
+    private static final String DEVICE_NAME = "deviceName";
+    private static final String INTF = "intf";
+    private static final String PCI_ADDRESS = "pciAddress";
+    private static final String TYPE = "type";
+    private static final String MTU = "mtu";
+
+    private static final String NOT_NULL_MESSAGE = "dpdk interface cannot be null";
+    private static final String MISSING_MESSAGE = " is required in DpdkInterface";
+
+    @Override
+    public ObjectNode encode(DpdkInterface entity, CodecContext context) {
+        checkNotNull(entity, NOT_NULL_MESSAGE);
+
+        return context.mapper().createObjectNode()
+                .put(DEVICE_NAME, entity.deviceName())
+                .put(INTF, entity.intf())
+                .put(PCI_ADDRESS, entity.pciAddress())
+                .put(TYPE, entity.type().name())
+                .put(MTU, entity.mtu().toString());
+    }
+
+    @Override
+    public DpdkInterface decode(ObjectNode json, CodecContext context) {
+        if (json == null || !json.isObject()) {
+            return null;
+        }
+
+        String deviceName = nullIsIllegal(json.get(DEVICE_NAME).asText(),
+                DEVICE_NAME + MISSING_MESSAGE);
+        String intf = nullIsIllegal(json.get(INTF).asText(),
+                INTF + MISSING_MESSAGE);
+        String pciAddress = nullIsIllegal(json.get(PCI_ADDRESS).asText(),
+                PCI_ADDRESS + MISSING_MESSAGE);
+        String typeString = nullIsIllegal(json.get(TYPE).asText(),
+                TYPE + MISSING_MESSAGE);
+
+        Type type;
+        try {
+            type = Type.valueOf(typeString.toUpperCase());
+        } catch (IllegalArgumentException e) {
+            throw new IllegalArgumentException(TYPE + MISSING_MESSAGE);
+        }
+
+        DpdkInterface.Builder builder = DefaultDpdkInterface.builder()
+                .deviceName(deviceName)
+                .intf(intf)
+                .pciAddress(pciAddress)
+                .type(type);
+
+        JsonNode mtuJson = json.get(MTU);
+
+        if (mtuJson != null) {
+            builder.mtu(Long.parseLong(mtuJson.asText()));
+        }
+
+        return builder.build();
+    }
+}