Java tutorial
/* * Copyright 2016-present 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.lisp.ctl.impl; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.ChannelInboundHandlerAdapter; import io.netty.handler.timeout.IdleState; import io.netty.handler.timeout.IdleStateEvent; import io.netty.util.ReferenceCountUtil; import org.onlab.packet.IpAddress; import org.onosproject.lisp.ctl.LispRouter; import org.onosproject.lisp.ctl.LispRouterFactory; import org.onosproject.lisp.msg.protocols.LispEncapsulatedControl; import org.onosproject.lisp.msg.protocols.LispInfoReply; import org.onosproject.lisp.msg.protocols.LispInfoRequest; import org.onosproject.lisp.msg.protocols.LispMapNotify; import org.onosproject.lisp.msg.protocols.LispMapRegister; import org.onosproject.lisp.msg.protocols.LispMapRequest; import org.onosproject.lisp.msg.protocols.LispMessage; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.util.List; import static org.onlab.packet.IpAddress.valueOf; /** * Channel handler deals with the xTR connection and dispatches xTR messages * to the appropriate locations. */ public class LispChannelHandler extends ChannelInboundHandlerAdapter { private final Logger log = LoggerFactory.getLogger(getClass()); private final LispRouterFactory routerFactory = LispRouterFactory.getInstance(); private LispRouter router; @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { try { // process map-request message that is encapsulated in ECM if (msg instanceof LispEncapsulatedControl) { LispMessage innerMsg = extractLispMessage((LispEncapsulatedControl) msg); if (innerMsg instanceof LispMapRequest) { LispMapResolver mapResolver = LispMapResolver.getInstance(); List<LispMessage> lispMessages = mapResolver.processMapRequest((LispEncapsulatedControl) msg); if (lispMessages != null) { lispMessages.forEach(ctx::writeAndFlush); } } } // process map-register message if (msg instanceof LispMapRegister) { LispMapRegister register = (LispMapRegister) msg; IpAddress xtrAddress = valueOf(register.getSender().getAddress()); router = routerFactory.getRouterInstance(xtrAddress); router.setChannel(ctx.channel()); router.connectRouter(); router.handleMessage(register); LispMapServer mapServer = LispMapServer.getInstance(); LispMapNotify mapNotify = mapServer.processMapRegister(register); if (mapNotify != null) { ctx.writeAndFlush(mapNotify); } } // process info-request message if (msg instanceof LispInfoRequest) { LispMapServer mapServer = LispMapServer.getInstance(); LispInfoReply infoReply = mapServer.processInfoRequest((LispInfoRequest) msg); if (infoReply != null) { ctx.writeAndFlush(infoReply); } } } finally { // try to remove the received message form the buffer ReferenceCountUtil.release(msg); } } @Override public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception { if (evt instanceof IdleStateEvent) { IdleStateEvent event = (IdleStateEvent) evt; if (event.state() == IdleState.READER_IDLE) { log.info("READER_IDLE read timeout"); ctx.disconnect(); } else if (event.state() == IdleState.WRITER_IDLE) { log.info("WRITER_IDLE write timeout"); ctx.disconnect(); } else if (event.state() == IdleState.ALL_IDLE) { log.info("ALL_IDLE total timeout"); ctx.disconnect(); } } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { log.warn(cause.getMessage()); //TODO: add error handle mechanisms for each cases } /** * Extracts LISP message from encapsulated control message. * * @param ecm Encapsulated Control Message * @return extracted LISP message */ private LispMessage extractLispMessage(LispEncapsulatedControl ecm) { LispMessage message = ecm.getControlMessage(); message.configSender(ecm.getSender()); return message; } }