[Emu][onos-2603] - Implement LinkState Link attributes-Shared Risk Link Group

Change-Id: I11400373d6206605811cf007f534f810cee31ddc

+/*
+ * 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.ArrayList;
+import java.util.List;
+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 com.google.common.base.MoreObjects;
+
+/**
+ * Implements BGP link Shared Risk Link Group attribute.
+ */
+public class BgpLinkAttrSrlg implements BGPValueType {
+
+    public static final short ATTRNODE_SRLG = 1097;
+
+    /* Shared Risk Link Group */
+    private List<Integer> sRlg = new ArrayList<Integer>();
+
+    /**
+     * Constructor to initialize the date.
+     *
+     * @param sRlg Shared Risk link group data
+     */
+    public BgpLinkAttrSrlg(List<Integer> sRlg) {
+        this.sRlg = sRlg;
+    }
+
+    /**
+     * Returns object of this class with specified values.
+     *
+     * @param sRlg Shared Risk link group data
+     * @return object of BgpLinkAttrSrlg
+     */
+    public static BgpLinkAttrSrlg of(ArrayList<Integer> sRlg) {
+        return new BgpLinkAttrSrlg(sRlg);
+    }
+
+    /**
+     * Reads the BGP link attributes Shared Risk link group data.
+     *
+     * @param cb Channel buffer
+     * @return object of type BgpLinkAttrSrlg
+     * @throws BGPParseException while parsing BgpLinkAttrSrlg
+     */
+    public static BgpLinkAttrSrlg read(ChannelBuffer cb)
+            throws BGPParseException {
+        int tempSrlg;
+        ArrayList<Integer> sRlg = new ArrayList<Integer>();
+
+        short lsAttrLength = cb.readShort();
+        int len = lsAttrLength / Integer.SIZE; // each element is of 4 octets
+
+        if (cb.readableBytes() < lsAttrLength) {
+            Validation.validateLen(BGPErrorType.UPDATE_MESSAGE_ERROR,
+                                   BGPErrorType.ATTRIBUTE_LENGTH_ERROR,
+                                   lsAttrLength);
+        }
+
+        for (int i = 0; i < len; i++) {
+            tempSrlg = cb.readInt();
+            sRlg.add(new Integer(tempSrlg));
+        }
+
+        return BgpLinkAttrSrlg.of(sRlg);
+    }
+
+    /**
+     * Returns the Shared Risk link group data.
+     *
+     * @return array of Shared Risk link group data
+     */
+    public List<Integer> attrSrlg() {
+        return sRlg;
+    }
+
+    @Override
+    public short getType() {
+        return ATTRNODE_SRLG;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(sRlg);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof BgpLinkAttrSrlg) {
+            BgpLinkAttrSrlg other = (BgpLinkAttrSrlg) obj;
+            return Objects.equals(sRlg, other.sRlg);
+        }
+        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()).omitNullValues().add("sRlg", sRlg).toString();
+    }
+}