[onos-2603] - Implement Is Is Administrative area

Change-Id: I28c1b5461dd719af920f6c28f3b8f1e4e05222eb

+/*
+ * 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.types.attr;
+
+import java.util.Objects;
+
+import org.jboss.netty.buffer.ChannelBuffer;
+import org.onosproject.bgpio.exceptions.BGPParseException;
+import org.onosproject.bgpio.types.BGPErrorType;
+import org.onosproject.bgpio.types.BGPValueType;
+import org.onosproject.bgpio.util.Validation;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.base.MoreObjects;
+
+/**
+ * Implements BGP attribute Is Is Administrative area.
+ */
+public final class BgpLinkAttrIsIsAdminstGrp implements BGPValueType {
+
+    protected static final Logger log = LoggerFactory
+            .getLogger(BgpLinkAttrIsIsAdminstGrp.class);
+
+    public static final int ATTRLINK_PROTECTIONTYPE = 1088;
+    public static final int ISIS_ADMIN_DATA_LEN = 4;
+
+    /* ISIS administrative group */
+    private final long isisAdminGrp;
+
+    /**
+     * Constructor to initialize the values.
+     *
+     * @param isisAdminGrp ISIS protocol admin group
+     */
+    public BgpLinkAttrIsIsAdminstGrp(long isisAdminGrp) {
+        this.isisAdminGrp = isisAdminGrp;
+    }
+
+    /**
+     * Returns object of this class with specified values.
+     *
+     * @param isisAdminGrp ISIS admin group
+     * @return object of BgpLinkAttrIsIsAdminstGrp
+     */
+    public static BgpLinkAttrIsIsAdminstGrp of(final long isisAdminGrp) {
+        return new BgpLinkAttrIsIsAdminstGrp(isisAdminGrp);
+    }
+
+    /**
+     * Reads the BGP link attributes of ISIS administrative group area.
+     *
+     * @param cb Channel buffer
+     * @return object of type BgpLinkAttrIsIsAdminstGrp
+     * @throws BGPParseException while parsing BgpLinkAttrIsIsAdminstGrp
+     */
+    public static BgpLinkAttrIsIsAdminstGrp read(ChannelBuffer cb)
+            throws BGPParseException {
+        long isisAdminGrp;
+        short lsAttrLength = cb.readShort();
+
+        if ((lsAttrLength != ISIS_ADMIN_DATA_LEN)
+                || (cb.readableBytes() < lsAttrLength)) {
+            Validation.validateLen(BGPErrorType.UPDATE_MESSAGE_ERROR,
+                                   BGPErrorType.ATTRIBUTE_LENGTH_ERROR,
+                                   lsAttrLength);
+        }
+
+        isisAdminGrp = cb.readUnsignedInt();
+
+        return BgpLinkAttrIsIsAdminstGrp.of(isisAdminGrp);
+    }
+
+    /**
+     * Link attributes of ISIS administrative group area.
+     *
+     * @return long value of the administrative group area
+     */
+    public long linkAttrIsIsAdminGrp() {
+        return isisAdminGrp;
+    }
+
+    @Override
+    public short getType() {
+        return ATTRLINK_PROTECTIONTYPE;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(isisAdminGrp);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof BgpLinkAttrIsIsAdminstGrp) {
+            BgpLinkAttrIsIsAdminstGrp other = (BgpLinkAttrIsIsAdminstGrp) obj;
+            return Objects.equals(isisAdminGrp, other.isisAdminGrp);
+        }
+        return false;
+    }
+
+    @Override
+    public int write(ChannelBuffer cb) {
+        // TODO This will be implemented in the next version
+        return 0;
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .add("isisAdminGrp", isisAdminGrp).toString();
+    }
+}