Adding BGP provider code to support EVPN

Change-Id: Ic5508749b64a47a70f1aabd9324e9f89e85fa39f
diff --git a/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/types/BgpEvpnLabel.java b/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/types/BgpEvpnLabel.java
new file mode 100755
index 0000000..60348ac
--- /dev/null
+++ b/protocols/bgp/bgpio/src/main/java/org/onosproject/bgpio/types/BgpEvpnLabel.java
@@ -0,0 +1,108 @@
+/*
+ * Copyright 2017-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.bgpio.types;
+
+import java.util.Objects;
+import org.jboss.netty.buffer.ChannelBuffer;
+import com.google.common.base.MoreObjects;
+
+public class BgpEvpnLabel implements Comparable<BgpEvpnLabel> {
+
+    public static final int MPLS_LABEL_LENGTH = 3;
+    private byte[] mplsLabel;
+
+    /**
+     * Resets fields.
+     */
+    public BgpEvpnLabel() {
+        this.mplsLabel = null;
+    }
+
+    /**
+     * Constructor to initialize parameters.
+     *
+     * @param bgpEvpnLabel mpls label
+     */
+    public BgpEvpnLabel(byte[] bgpEvpnLabel) {
+        this.mplsLabel = bgpEvpnLabel;
+    }
+
+    /**
+     * Reads mpls label from channelBuffer.
+     *
+     * @param cb channelBuffer
+     * @return object of mpls label
+     */
+    public static BgpEvpnLabel read(ChannelBuffer cb) {
+        return new BgpEvpnLabel(cb.readBytes(3).array());
+    }
+
+    /**
+     * writes mpls label into channelBuffer.
+     *
+     * @param cb channelBuffer
+     * @return length length of written data
+     */
+    public int write(ChannelBuffer cb) {
+        int iLenStartIndex = cb.writerIndex();
+        cb.writeBytes(mplsLabel);
+        return cb.writerIndex() - iLenStartIndex;
+    }
+
+    /**
+     * Returns mpls label.
+     *
+     * @return mpls label
+     */
+    public byte[] getMplsLabel() {
+        return this.mplsLabel;
+    }
+
+    @Override
+    public int compareTo(BgpEvpnLabel mplsLabel) {
+        return 0;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof BgpEvpnLabel) {
+
+            BgpEvpnLabel that = (BgpEvpnLabel) obj;
+
+            if (this.mplsLabel == that.mplsLabel) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(mplsLabel);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .add("mplsLabel", mplsLabel).toString();
+    }
+}