Java tutorial
/* * Copyright (c) 2013 Cisco Systems, Inc. and others. All rights reserved. * * This program and the accompanying materials are made available under the * terms of the Eclipse Public License v1.0 which accompanies this distribution, * and is available at http://www.eclipse.org/legal/epl-v10.html */ package org.opendaylight.protocol.bgp.parser.impl.message; import com.google.common.base.Preconditions; import io.netty.buffer.ByteBuf; import io.netty.buffer.ByteBufUtil; import io.netty.buffer.Unpooled; import java.util.Arrays; import org.opendaylight.protocol.bgp.parser.BGPDocumentedException; import org.opendaylight.protocol.bgp.parser.BGPError; import org.opendaylight.protocol.bgp.parser.spi.MessageParser; import org.opendaylight.protocol.bgp.parser.spi.MessageSerializer; import org.opendaylight.protocol.bgp.parser.spi.MessageUtil; import org.opendaylight.protocol.util.ByteArray; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.NotifyBuilder; import org.opendaylight.yangtools.yang.binding.Notification; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Parser for BGPNotification message. */ public final class BGPNotificationMessageParser implements MessageParser, MessageSerializer { private static final Logger LOG = LoggerFactory.getLogger(BGPNotificationMessageParser.class); public static final int TYPE = 3; private static final int ERROR_SIZE = 2; /** * Serializes BGP Notification message. * * @param msg to be serialized * @param bytes ByteBuf where the message will be serialized */ @Override public void serializeMessage(final Notification msg, final ByteBuf bytes) { Preconditions.checkArgument(msg instanceof Notify, "Message needs to be of type Notify"); final Notify ntf = (Notify) msg; final ByteBuf msgBody = Unpooled.buffer(); msgBody.writeByte(ntf.getErrorCode()); msgBody.writeByte(ntf.getErrorSubcode()); final byte[] data = ntf.getData(); if (data != null) { msgBody.writeBytes(data); } LOG.trace("Notification message serialized to: {}", ByteBufUtil.hexDump(msgBody)); MessageUtil.formatMessage(TYPE, msgBody, bytes); } /** * Parses BGP Notification message to bytes. * * @param body ByteBuf to be parsed * @param messageLength the length of the message * @return {@link Notify} which represents BGP notification message * @throws BGPDocumentedException if parsing goes wrong */ @Override public Notify parseMessageBody(final ByteBuf body, final int messageLength) throws BGPDocumentedException { Preconditions.checkArgument(body != null, "Buffer cannot be null."); if (body.readableBytes() < ERROR_SIZE) { throw BGPDocumentedException.badMessageLength("Notification message too small.", messageLength); } final int errorCode = body.readUnsignedByte(); final int errorSubcode = body.readUnsignedByte(); final NotifyBuilder builder = new NotifyBuilder().setErrorCode((short) errorCode) .setErrorSubcode((short) errorSubcode); if (body.isReadable()) { builder.setData(ByteArray.readAllBytes(body)); } LOG.debug("BGP Notification message was parsed: err = {}, data = {}.", BGPError.forValue(errorCode, errorSubcode), Arrays.toString(builder.getData())); return builder.build(); } }