[ONOS-4718] Initial implementation of LISP address serializer

Change-Id: I71e1923f6daf1abdf2bf9798a9e421c81926a45c
diff --git a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/LispMacAddress.java b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/LispMacAddress.java
index ba789b6..6828581 100644
--- a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/LispMacAddress.java
+++ b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/types/LispMacAddress.java
@@ -18,6 +18,7 @@
 import io.netty.buffer.ByteBuf;
 import org.onlab.packet.MacAddress;
 import org.onosproject.lisp.msg.exceptions.LispParseError;
+import org.onosproject.lisp.msg.exceptions.LispWriterException;
 
 import java.util.Objects;
 
@@ -88,4 +89,16 @@
             return new LispMacAddress(macAddress);
         }
     }
+
+    /**
+     * MAC address writer class.
+     */
+    public static class MacAddressWriter implements LispAddressWriter<LispMacAddress> {
+
+        @Override
+        public void writeTo(ByteBuf byteBuf, LispMacAddress address) throws LispWriterException {
+            byte[] macByte = address.getAddress().toBytes();
+            byteBuf.writeBytes(macByte);
+        }
+    }
 }