[ONOS-2589] Generate Bgp uri for Node and Link changes of BGP Controller.

Change-Id: Ibbf3a57dacda31a4047538f5ba070cd5d50cf8cb

+/*
+ * 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.bgp.controller;
+
+import static com.google.common.base.Preconditions.checkArgument;
+
+import java.net.URI;
+import java.net.URISyntaxException;
+
+import org.onosproject.bgpio.exceptions.BGPParseException;
+import org.onosproject.bgpio.protocol.linkstate.BgpLinkLsNlriVer4;
+import org.onosproject.bgpio.protocol.linkstate.BGPNodeLSNlriVer4;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * The class representing a network  bgp device id. This class is immutable.
+ */
+public final class BgpDpid {
+    private static final Logger log = LoggerFactory.getLogger(BgpDpid.class);
+
+    private static final String SCHEME = "bgp";
+    private static final long UNKNOWN = 0;
+    private StringBuilder stringBuilder;
+    public static final int NODE_DESCRIPTOR_LOCAL = 1;
+    public static final int NODE_DESCRIPTOR_REMOTE = 2;
+
+    /**
+     * Initialize bgp id to generate URI.
+     *
+     * @param linkNlri node Nlri.
+     * @param nodeDescriptorType node descriptor type, local/remote
+     */
+    public BgpDpid(final BgpLinkLsNlriVer4 linkNlri, int nodeDescriptorType) {
+        this.stringBuilder = new StringBuilder("bgpls://");
+
+        if (linkNlri.getRouteDistinguisher() != null) {
+            this.stringBuilder.append(Long.toString(linkNlri.getRouteDistinguisher().getRouteDistinguisher()))
+                              .append(':');
+        }
+
+        try {
+            this.stringBuilder.append(linkNlri.getProtocolId().toString())
+                              .append(':')
+                              .append(Long.toString(linkNlri.getIdentifier()))
+                              .append('/');
+
+            if (nodeDescriptorType == NODE_DESCRIPTOR_LOCAL) {
+                add(linkNlri.localNodeDescriptors().toString());
+            } else if (nodeDescriptorType == NODE_DESCRIPTOR_REMOTE) {
+                add(linkNlri.remoteNodeDescriptors().toString());
+            }
+        } catch (BGPParseException e) {
+            log.info("Exception BgpId string: " + e.toString());
+        }
+
+    }
+
+    /**
+     * Initialize bgp id to generate URI.
+     *
+     * @param nodeNlri node Nlri.
+     */
+    public BgpDpid(final BGPNodeLSNlriVer4 nodeNlri) {
+        this.stringBuilder = new StringBuilder("bgpls://");
+
+        if (nodeNlri.getRouteDistinguisher() != null) {
+            this.stringBuilder.append(Long.toString(nodeNlri.getRouteDistinguisher().getRouteDistinguisher()))
+                              .append(':');
+        }
+
+        try {
+
+            this.stringBuilder.append(nodeNlri.getProtocolId().toString())
+                              .append(':')
+                              .append(Long.toString(nodeNlri.getIdentifier()))
+                              .append('/');
+
+            add(nodeNlri.getLocalNodeDescriptors().toString());
+
+        } catch (BGPParseException e) {
+            log.info("Exception node string: " + e.toString());
+        }
+    }
+
+    BgpDpid add(final Object value) {
+        if (value != null) {
+            this.stringBuilder.append('&').append('=').append(value.toString());
+        }
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        return this.stringBuilder.toString();
+    }
+
+    /**
+     * Produces bgp URI.
+     *
+     * @param value string to get URI
+     * @return bgp URI, otherwise null
+     */
+    public static URI uri(String value) {
+        try {
+            return new URI(SCHEME, value, null);
+        } catch (URISyntaxException e) {
+            log.info("Exception BgpId URI: " + e.toString());
+        }
+        return null;
+    }
+
+    /**
+     * Returns bgpDpid created from the given device URI.
+     *
+     * @param uri device URI
+     * @return object of BgpDpid
+     */
+    public static BgpDpid bgpDpid(URI uri) {
+        checkArgument(uri.getScheme().equals(SCHEME), "Unsupported URI scheme");
+
+        // TODO: return BgpDpid generated from uri
+        return null;
+    }
+}