[ONOS-6169] Implement codec for segment and SrcDst ext addresses

Change-Id: Id928a3bb2dd914f8411cc6353bb41c5f05fb54a4
diff --git a/drivers/lisp/src/main/java/org/onosproject/drivers/lisp/extensions/codec/LispSrcDstAddressCodec.java b/drivers/lisp/src/main/java/org/onosproject/drivers/lisp/extensions/codec/LispSrcDstAddressCodec.java
new file mode 100644
index 0000000..cad5aec
--- /dev/null
+++ b/drivers/lisp/src/main/java/org/onosproject/drivers/lisp/extensions/codec/LispSrcDstAddressCodec.java
@@ -0,0 +1,99 @@
+/*
+ * Copyright 2017-present 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.drivers.lisp.extensions.codec;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.drivers.lisp.extensions.LispSrcDstAddress;
+import org.onosproject.mapping.addresses.MappingAddress;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.onlab.util.Tools.nullIsIllegal;
+
+/**
+ * LISP source destination address codec.
+ */
+public final class LispSrcDstAddressCodec extends JsonCodec<LispSrcDstAddress> {
+
+    protected static final String SRC_MASK_LENGTH = "srcMaskLength";
+    protected static final String DST_MASK_LENGTH = "dstMaskLength";
+    protected static final String SRC_PREFIX = "srcPrefix";
+    protected static final String DST_PREFIX = "dstPrefix";
+
+    private static final String MISSING_MEMBER_MESSAGE =
+                                " member is required in LispSrcDstAddress";
+
+    @Override
+    public ObjectNode encode(LispSrcDstAddress address, CodecContext context) {
+        checkNotNull(address, "LispSrcDstAddress cannot be null");
+
+        final JsonCodec<MappingAddress> addressCodec =
+                context.codec(MappingAddress.class);
+
+        final ObjectNode result = context.mapper().createObjectNode()
+                .put(SRC_MASK_LENGTH, address.getSrcMaskLength())
+                .put(DST_MASK_LENGTH, address.getDstMaskLength());
+
+        if (address.getSrcPrefix() != null) {
+            ObjectNode srcPrefix = addressCodec.encode(address.getSrcPrefix(), context);
+            result.set(SRC_PREFIX, srcPrefix);
+        }
+
+        if (address.getDstPrefix() != null) {
+            ObjectNode dstPrefix = addressCodec.encode(address.getDstPrefix(), context);
+            result.set(DST_PREFIX, dstPrefix);
+        }
+
+        return result;
+    }
+
+    @Override
+    public LispSrcDstAddress decode(ObjectNode json, CodecContext context) {
+        if (json == null || !json.isObject()) {
+            return null;
+        }
+
+        byte srcMaskLength = (byte) nullIsIllegal(json.get(SRC_MASK_LENGTH),
+                SRC_MASK_LENGTH + MISSING_MEMBER_MESSAGE).asInt();
+        byte dstMaskLength = (byte) nullIsIllegal(json.get(DST_MASK_LENGTH),
+                DST_MASK_LENGTH + MISSING_MEMBER_MESSAGE).asInt();
+
+        final JsonCodec<MappingAddress> addressCodec =
+                context.codec(MappingAddress.class);
+
+        ObjectNode srcPrefixJson = get(json, SRC_PREFIX);
+        MappingAddress srcPrefix = null;
+
+        ObjectNode dstPrefixJson = get(json, DST_PREFIX);
+        MappingAddress dstPrefix = null;
+
+        if (srcPrefixJson != null) {
+            srcPrefix = addressCodec.decode(srcPrefixJson, context);
+        }
+
+        if (dstPrefixJson != null) {
+            dstPrefix = addressCodec.decode(dstPrefixJson, context);
+        }
+
+        return new LispSrcDstAddress.Builder()
+                            .withSrcMaskLength(srcMaskLength)
+                            .withDstMaskLength(dstMaskLength)
+                            .withSrcPrefix(srcPrefix)
+                            .withDstPrefix(dstPrefix)
+                            .build();
+    }
+}