Priyanka B | 8584395 | 2015-10-14 11:56:30 +0530 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 Open Networking Laboratory |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.onosproject.bgpio.types; |
| 17 | |
| 18 | import java.util.Objects; |
| 19 | |
| 20 | import org.jboss.netty.buffer.ChannelBuffer; |
| 21 | import org.onosproject.bgpio.exceptions.BGPParseException; |
| 22 | import org.onosproject.bgpio.util.Validation; |
| 23 | import org.slf4j.Logger; |
| 24 | import org.slf4j.LoggerFactory; |
| 25 | |
| 26 | import com.google.common.base.MoreObjects; |
| 27 | |
| 28 | /** |
| 29 | * Provides Implementation of Med BGP Path Attribute. |
| 30 | */ |
| 31 | public class Med implements BGPValueType { |
| 32 | private static final Logger log = LoggerFactory.getLogger(Med.class); |
| 33 | public static final byte MED_TYPE = 4; |
| 34 | public static final int TYPE_AND_LEN_AS_SHORT = 4; |
| 35 | public static final int TYPE_AND_LEN_AS_BYTE = 3; |
| 36 | public static final byte MED_MAX_LEN = 4; |
| 37 | |
| 38 | private int med; |
| 39 | |
| 40 | /** |
| 41 | * Constructor to initialize med. |
| 42 | * |
| 43 | * @param med MULTI_EXIT_DISC value |
| 44 | */ |
| 45 | public Med(int med) { |
| 46 | this.med = med; |
| 47 | } |
| 48 | |
| 49 | /** |
| 50 | * Returns Med value. |
| 51 | * |
| 52 | * @return Med value |
| 53 | */ |
| 54 | public int med() { |
| 55 | return this.med; |
| 56 | } |
| 57 | |
| 58 | /** |
| 59 | * Reads the channel buffer and returns object of Med. |
| 60 | * |
| 61 | * @param cb ChannelBuffer |
| 62 | * @return object of Med |
| 63 | * @throws BGPParseException while parsing Med path attribute |
| 64 | */ |
| 65 | public static Med read(ChannelBuffer cb) throws BGPParseException { |
| 66 | int med; |
| 67 | ChannelBuffer tempCb = cb.copy(); |
| 68 | Validation parseFlags = Validation.parseAttributeHeader(cb); |
| 69 | |
| 70 | if ((parseFlags.getLength() > MED_MAX_LEN) || cb.readableBytes() < parseFlags.getLength()) { |
| 71 | Validation.validateLen(BGPErrorType.UPDATE_MESSAGE_ERROR, BGPErrorType.ATTRIBUTE_LENGTH_ERROR, |
| 72 | parseFlags.getLength()); |
| 73 | } |
| 74 | int len = parseFlags.isShort() ? parseFlags.getLength() + TYPE_AND_LEN_AS_SHORT : parseFlags |
| 75 | .getLength() + TYPE_AND_LEN_AS_BYTE; |
| 76 | ChannelBuffer data = tempCb.readBytes(len); |
| 77 | if (!parseFlags.getFirstBit() && parseFlags.getSecondBit() && parseFlags.getThirdBit()) { |
| 78 | throw new BGPParseException(BGPErrorType.UPDATE_MESSAGE_ERROR, BGPErrorType.ATTRIBUTE_FLAGS_ERROR, data); |
| 79 | } |
| 80 | |
| 81 | med = cb.readInt(); |
| 82 | return new Med(med); |
| 83 | } |
| 84 | |
| 85 | @Override |
| 86 | public short getType() { |
| 87 | return MED_TYPE; |
| 88 | } |
| 89 | |
| 90 | @Override |
| 91 | public int hashCode() { |
| 92 | return Objects.hash(med); |
| 93 | } |
| 94 | |
| 95 | @Override |
| 96 | public boolean equals(Object obj) { |
| 97 | if (this == obj) { |
| 98 | return true; |
| 99 | } |
| 100 | if (obj instanceof Med) { |
| 101 | Med other = (Med) obj; |
| 102 | return Objects.equals(med, other.med); |
| 103 | } |
| 104 | return false; |
| 105 | } |
| 106 | |
| 107 | @Override |
| 108 | public String toString() { |
| 109 | return MoreObjects.toStringHelper(getClass()) |
| 110 | .add("med", med) |
| 111 | .toString(); |
| 112 | } |
| 113 | |
| 114 | @Override |
| 115 | public int write(ChannelBuffer cb) { |
| 116 | //Not to implement as of now |
| 117 | return 0; |
| 118 | } |
| 119 | } |