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.spi.pojo; import com.google.common.base.Preconditions; import com.google.common.collect.Iterables; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import java.util.AbstractMap; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentMap; import org.opendaylight.bgp.concepts.NextHopUtil; import org.opendaylight.protocol.bgp.parser.BGPParsingException; import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl; import org.opendaylight.protocol.bgp.parser.spi.AddressFamilyRegistry; import org.opendaylight.protocol.bgp.parser.spi.NextHopParserSerializer; import org.opendaylight.protocol.bgp.parser.spi.NlriParser; import org.opendaylight.protocol.bgp.parser.spi.NlriRegistry; import org.opendaylight.protocol.bgp.parser.spi.NlriSerializer; import org.opendaylight.protocol.bgp.parser.spi.PeerSpecificParserConstraint; import org.opendaylight.protocol.bgp.parser.spi.SubsequentAddressFamilyRegistry; import org.opendaylight.protocol.concepts.AbstractRegistration; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpReachNlri; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpReachNlriBuilder; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpUnreachNlri; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.update.attributes.MpUnreachNlriBuilder; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.AddressFamily; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.SubsequentAddressFamily; import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.next.hop.CNextHop; import org.opendaylight.yangtools.yang.binding.DataObject; import org.slf4j.Logger; import org.slf4j.LoggerFactory; final class SimpleNlriRegistry implements NlriRegistry { private static final int RESERVED = 1; private static final int NEXT_HOP_LENGHT = 1; private static final String PARSER_NOT_FOUND = "Nlri parser not found for table type {}"; private static final Logger LOG = LoggerFactory.getLogger(SimpleNlriRegistry.class); private final ConcurrentMap<BgpTableType, NlriParser> handlers = new ConcurrentHashMap<>(); private final ConcurrentMap<Class<? extends DataObject>, NlriSerializer> serializers = new ConcurrentHashMap<>(); private final ConcurrentMap<BgpTableType, NextHopParserSerializer> nextHopParsers = new ConcurrentHashMap<>(); private final ConcurrentMap<Map.Entry<Class<? extends CNextHop>, BgpTableType>, NextHopParserSerializer> nextHopSerializers = new ConcurrentHashMap<>(); private final SubsequentAddressFamilyRegistry safiReg; private final AddressFamilyRegistry afiReg; public SimpleNlriRegistry(final AddressFamilyRegistry afiReg, final SubsequentAddressFamilyRegistry safiReg) { this.afiReg = Preconditions.checkNotNull(afiReg); this.safiReg = Preconditions.checkNotNull(safiReg); } private static BgpTableType createKey(final Class<? extends AddressFamily> afi, final Class<? extends SubsequentAddressFamily> safi) { Preconditions.checkNotNull(afi); Preconditions.checkNotNull(safi); return new BgpTableTypeImpl(afi, safi); } synchronized AutoCloseable registerNlriSerializer(final Class<? extends DataObject> nlriClass, final NlriSerializer serializer) { final NlriSerializer prev = this.serializers.get(nlriClass); Preconditions.checkState(prev == null, "Serializer already bound to class " + prev); this.serializers.put(nlriClass, serializer); final Object lock = this; return new AbstractRegistration() { @Override protected void removeRegistration() { synchronized (lock) { SimpleNlriRegistry.this.serializers.remove(nlriClass); } } }; } synchronized AutoCloseable registerNlriParser(final Class<? extends AddressFamily> afi, final Class<? extends SubsequentAddressFamily> safi, final NlriParser parser, final NextHopParserSerializer nextHopSerializer, final Class<? extends CNextHop> cNextHopClass, final Class<? extends CNextHop>... cNextHopClassList) { final BgpTableType key = createKey(afi, safi); final NlriParser prev = this.handlers.get(key); Preconditions.checkState(prev == null, "AFI/SAFI is already bound to parser " + prev); this.handlers.put(key, parser); this.nextHopParsers.put(key, nextHopSerializer); if (cNextHopClass != null) { final Map.Entry<Class<? extends CNextHop>, BgpTableType> nhKey = new AbstractMap.SimpleEntry( cNextHopClass, key); this.nextHopSerializers.put(nhKey, nextHopSerializer); for (final Class<? extends CNextHop> cNextHop : cNextHopClassList) { final Map.Entry<Class<? extends CNextHop>, BgpTableType> nhKeys = new AbstractMap.SimpleEntry( cNextHop, key); this.nextHopSerializers.put(nhKeys, nextHopSerializer); } } final Object lock = this; return new AbstractRegistration() { @Override protected void removeRegistration() { synchronized (lock) { SimpleNlriRegistry.this.handlers.remove(key); SimpleNlriRegistry.this.nextHopParsers.remove(key); if (cNextHopClass != null) { final Map.Entry<Class<? extends CNextHop>, BgpTableType> nhKey = new AbstractMap.SimpleEntry( cNextHopClass, key); SimpleNlriRegistry.this.nextHopSerializers.remove(nhKey); for (final Class<? extends CNextHop> cNextHop : cNextHopClassList) { final Map.Entry<Class<? extends CNextHop>, BgpTableType> nhKeys = new AbstractMap.SimpleEntry( cNextHop, key); SimpleNlriRegistry.this.nextHopSerializers.remove(nhKeys); } } } } }; } private Class<? extends AddressFamily> getAfi(final ByteBuf buffer) throws BGPParsingException { final int afiVal = buffer.readUnsignedShort(); final Class<? extends AddressFamily> afi = this.afiReg.classForFamily(afiVal); if (afi == null) { throw new BGPParsingException("Address Family Identifier: '" + afiVal + "' not supported."); } return afi; } private Class<? extends SubsequentAddressFamily> getSafi(final ByteBuf buffer) throws BGPParsingException { final int safiVal = buffer.readUnsignedByte(); final Class<? extends SubsequentAddressFamily> safi = this.safiReg.classForFamily(safiVal); if (safi == null) { throw new BGPParsingException("Subsequent Address Family Identifier: '" + safiVal + "' not supported."); } return safi; } @Override public MpUnreachNlri parseMpUnreach(final ByteBuf buffer) throws BGPParsingException { return parseMpUnreach(buffer, null); } @Override public MpUnreachNlri parseMpUnreach(final ByteBuf buffer, final PeerSpecificParserConstraint constraint) throws BGPParsingException { final MpUnreachNlriBuilder builder = new MpUnreachNlriBuilder(); builder.setAfi(getAfi(buffer)); builder.setSafi(getSafi(buffer)); final ByteBuf nlri = buffer.slice(); final BgpTableType key = createKey(builder.getAfi(), builder.getSafi()); final NlriParser parser = this.handlers.get(key); if (parser == null) { LOG.warn(PARSER_NOT_FOUND, key); } else { parser.parseNlri(nlri, builder, constraint); } return builder.build(); } @Override public void serializeMpReach(final MpReachNlri mpReachNlri, final ByteBuf byteAggregator) { final Class<? extends AddressFamily> afi = mpReachNlri.getAfi(); final Class<? extends SubsequentAddressFamily> safi = mpReachNlri.getSafi(); byteAggregator.writeShort(this.afiReg.numberForClass(afi)); byteAggregator.writeByte(this.safiReg.numberForClass(safi)); final CNextHop cNextHop = mpReachNlri.getCNextHop(); if (cNextHop != null) { final Map.Entry<Class<? extends CNextHop>, BgpTableType> key = new AbstractMap.SimpleEntry( cNextHop.getImplementedInterface(), new BgpTableTypeImpl(afi, safi)); final NextHopParserSerializer nextHopSerializer = this.nextHopSerializers.get(key); final ByteBuf nextHopBuffer = Unpooled.buffer(); if (nextHopSerializer == null) { //TODO Remove once deprecated registerNlriParser is removed LOG.warn("NexHop Parser/Serializer for AFI/SAFI ({},{}) not bound", afi, safi); NextHopUtil.serializeNextHop(cNextHop, nextHopBuffer); } else { nextHopSerializer.serializeNextHop(cNextHop, nextHopBuffer); } byteAggregator.writeByte(nextHopBuffer.writerIndex()); byteAggregator.writeBytes(nextHopBuffer); } else { byteAggregator.writeZero(NEXT_HOP_LENGHT); } byteAggregator.writeZero(RESERVED); } @Override public void serializeMpUnReach(final MpUnreachNlri mpUnreachNlri, final ByteBuf byteAggregator) { byteAggregator.writeShort(this.afiReg.numberForClass(mpUnreachNlri.getAfi())); byteAggregator.writeByte(this.safiReg.numberForClass(mpUnreachNlri.getSafi())); } @Override public Iterable<NlriSerializer> getSerializers() { return Iterables.unmodifiableIterable(this.serializers.values()); } @Override public MpReachNlri parseMpReach(final ByteBuf buffer) throws BGPParsingException { return parseMpReach(buffer, null); } @Override public MpReachNlri parseMpReach(final ByteBuf buffer, final PeerSpecificParserConstraint constraint) throws BGPParsingException { final MpReachNlriBuilder builder = new MpReachNlriBuilder(); final Class<? extends AddressFamily> afi = getAfi(buffer); final Class<? extends SubsequentAddressFamily> safi = getSafi(buffer); builder.setAfi(afi); builder.setSafi(safi); final BgpTableType key = createKey(builder.getAfi(), builder.getSafi()); final int nextHopLength = buffer.readUnsignedByte(); if (nextHopLength != 0) { final NextHopParserSerializer nextHopParser = this.nextHopParsers.get(key); if (nextHopParser != null) { builder.setCNextHop(nextHopParser.parseNextHop(buffer.readSlice(nextHopLength))); } else { builder.setCNextHop(NextHopUtil.parseNextHop(buffer.readSlice(nextHopLength))); LOG.warn("NexHop Parser/Serializer for AFI/SAFI ({},{}) not bound", afi, safi); } } buffer.skipBytes(RESERVED); final ByteBuf nlri = buffer.slice(); final NlriParser parser = this.handlers.get(key); if (parser == null) { LOG.warn(PARSER_NOT_FOUND, key); } else { parser.parseNlri(nlri, builder, constraint); } return builder.build(); } }