[ONOS-4718] Add skeleton code for de-serializing LISP ctrl messages

Change-Id: I52f7905538e5832e5282812df869b8158ce23334
diff --git a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java
index bbfe3b9..b77e580 100644
--- a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java
+++ b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/protocols/DefaultLispMapRegister.java
@@ -20,6 +20,7 @@
 import com.google.common.collect.Lists;
 import io.netty.buffer.ByteBuf;
 import org.onlab.util.ImmutableByteSequence;
+import org.onosproject.lisp.msg.exceptions.LispParseError;
 
 import java.util.List;
 
@@ -211,4 +212,15 @@
                     recordCount, mapRecords, proxyMapReply, wantMapNotify);
         }
     }
+
+    /**
+     * A private LISP message reader for MapRegister message.
+     */
+    private static class RegisterReader implements LispMessageReader<LispMapRegister> {
+
+        @Override
+        public LispMapRegister readFrom(ByteBuf byteBuf) throws LispParseError {
+            return null;
+        }
+    }
 }