[ONOS-2602]Implement Link NLRI

Change-Id: Ia17868c0a2f701a88d82171943c52fe7b7880fba

@@ -29,19 +29,19 @@ public interface BgpLinkLsNlri extends BGPLSNlri {
      *
      * @return local node descriptors
      */
-    NodeDescriptors getLocalNodeDescriptors();
+    NodeDescriptors localNodeDescriptors();
 
     /**
      * Returns remote node descriptors.
      *
      * @return remote node descriptors
      */
-    NodeDescriptors getRemoteNodeDescriptors();
+    NodeDescriptors remoteNodeDescriptors();
 
     /**
      * Returns link descriptors.
      *
      * @return link descriptors
      */
-    List<BGPValueType> getLinkDescriptors();
+    List<BGPValueType> linkDescriptors();
 }
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+/*
+ * Copyright 2015 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.bgpio.protocol.linkstate;
+
+import java.util.List;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.onosproject.bgpio.exceptions.BGPParseException;
+import org.onosproject.bgpio.protocol.BgpLinkLsNlri;
+import org.onosproject.bgpio.protocol.NlriType;
+import org.onosproject.bgpio.protocol.linkstate.BGPNodeLSNlriVer4.PROTOCOLTYPE;
+import org.onosproject.bgpio.types.BGPErrorType;
+import org.onosproject.bgpio.types.BGPValueType;
+import org.onosproject.bgpio.types.RouteDistinguisher;
+import org.onosproject.bgpio.util.Constants;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.base.MoreObjects;
+
+/**
+ * Implementation of Link LS NLRI.
+ */
+public class BgpLinkLsNlriVer4 implements BgpLinkLsNlri {
+
+    /*
+     * REFERENCE : draft-ietf-idr-ls-distribution-11
+          0                   1                   2                   3
+          0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+         +-+-+-+-+-+-+-+-+
+         |  Protocol-ID  |
+         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+         |                           Identifier                          |
+         |                            (64 bits)                          |
+         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+         //               Local Node Descriptors (variable)             //
+         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+         //               Remote Node Descriptors (variable)            //
+         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+         //                  Link Descriptors (variable)                //
+         +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+
+                          Figure : The Link NLRI format
+     */
+    private static final Logger log = LoggerFactory.getLogger(BgpLinkLsNlriVer4.class);
+    public static final int LINK_NLRITYPE = 2;
+
+    private BGPLinkLSIdentifier linkLSIdentifier;
+    private byte protocolId;
+    private long identifier;
+    private RouteDistinguisher routeDistinguisher;
+    private boolean isVpn;
+
+    /**
+     * Initialize fields.
+     */
+    public BgpLinkLsNlriVer4() {
+        this.protocolId = 0;
+        this.identifier = 0;
+        this.linkLSIdentifier = null;
+        this.routeDistinguisher = null;
+        this.isVpn = false;
+    }
+
+    /**
+     * Constructor to initialize parameters for BGP LinkLSNlri.
+     *
+     * @param protocolId protocol Id
+     * @param identifier field in BGP LinkLSNlri
+     * @param linkLSIdentifier link LS identifier
+     * @param routeDistinguisher route distinguisher from message
+     * @param isVpn vpn info availability in message
+     */
+    public BgpLinkLsNlriVer4(byte protocolId, long identifier, BGPLinkLSIdentifier linkLSIdentifier,
+                             RouteDistinguisher routeDistinguisher, boolean isVpn) {
+        this.protocolId = protocolId;
+        this.identifier = identifier;
+        this.linkLSIdentifier = linkLSIdentifier;
+        this.routeDistinguisher = routeDistinguisher;
+        this.isVpn = isVpn;
+    }
+
+    /**
+     * Reads from channelBuffer and parses Link LS Nlri.
+     *
+     * @param cb ChannelBuffer
+     * @param afi Address Family Identifier
+     * @param safi Subsequent Address Family Identifier
+     * @return object of this class
+     * @throws BGPParseException while parsing Link LS NLRI
+     */
+    public static BgpLinkLsNlriVer4 read(ChannelBuffer cb, short afi, byte safi) throws BGPParseException {
+        boolean isVpn = false;
+        RouteDistinguisher routeDistinguisher = null;
+        if ((afi == Constants.AFI_VALUE) && (safi == Constants.VPN_SAFI_VALUE)) {
+            routeDistinguisher = new RouteDistinguisher();
+            routeDistinguisher = RouteDistinguisher.read(cb);
+            isVpn = true;
+        } else {
+            isVpn = false;
+        }
+        byte protocolId = cb.readByte();
+        long identifier = cb.readLong();
+
+        BGPLinkLSIdentifier linkLSIdentifier = new BGPLinkLSIdentifier();
+        linkLSIdentifier = BGPLinkLSIdentifier.parseLinkIdendifier(cb, protocolId);
+        return new BgpLinkLsNlriVer4(protocolId, identifier, linkLSIdentifier, routeDistinguisher, isVpn);
+    }
+
+    @Override
+    public NlriType getNlriType() {
+        return NlriType.LINK;
+    }
+
+    @Override
+    public long getIdentifier() {
+        return this.identifier;
+    }
+
+    /**
+     * Set the link LS identifier.
+     *
+     * @param linkLSIdentifier link LS identifier to set
+     */
+    public void setLinkLSIdentifier(BGPLinkLSIdentifier linkLSIdentifier) {
+        this.linkLSIdentifier = linkLSIdentifier;
+    }
+
+    @Override
+    public PROTOCOLTYPE getProtocolId() throws BGPParseException {
+        switch (protocolId) {
+        case Constants.ISIS_LEVELONE:
+            return PROTOCOLTYPE.ISIS_LevelOne;
+        case Constants.ISIS_LEVELTWO:
+            return PROTOCOLTYPE.ISIS_LevelTwo;
+        case Constants.OSPFV2:
+            return PROTOCOLTYPE.OSPFv2;
+        case Constants.DIRECT:
+            return PROTOCOLTYPE.Direct;
+        case Constants.STATIC_CONFIGURATION:
+            return PROTOCOLTYPE.Static_Configuration;
+        case Constants.OSPFV3:
+            return PROTOCOLTYPE.OSPFv3;
+        default:
+            throw new BGPParseException(BGPErrorType.UPDATE_MESSAGE_ERROR, (byte) 0, null);
+        }
+    }
+
+    @Override
+    public NodeDescriptors localNodeDescriptors() {
+        return this.linkLSIdentifier.localNodeDescriptors();
+    }
+
+    @Override
+    public NodeDescriptors remoteNodeDescriptors() {
+        return this.linkLSIdentifier.remoteNodeDescriptors();
+    }
+
+    /**
+     * Returns whether VPN is present or not.
+     *
+     * @return whether VPN is present or not
+     */
+    public boolean isVpnPresent() {
+        return this.isVpn;
+    }
+
+    @Override
+    public RouteDistinguisher getRouteDistinguisher() {
+        return this.routeDistinguisher;
+    }
+
+    /**
+     * Returns link identifier.
+     *
+     * @return link identifier
+     */
+    public BGPLinkLSIdentifier getLinkIdentifier() {
+        return this.linkLSIdentifier;
+    }
+
+    @Override
+    public List<BGPValueType> linkDescriptors() {
+        return this.linkLSIdentifier.linkDescriptors();
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .omitNullValues()
+                .add("protocolId", protocolId)
+                .add("identifier", identifier)
+                .add("RouteDistinguisher ", routeDistinguisher)
+                .add("linkLSIdentifier", linkLSIdentifier)
+                .toString();
+    }
+}
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