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; 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.onosproject.lisp.msg.protocols.LispEncapsulatedControl; 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.LispMapReply; import org.onosproject.lisp.msg.protocols.LispMessage; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * 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()); @Override public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { // first we need to check whether this is an ECM if (msg instanceof LispEncapsulatedControl) { msg = extractMapRequest((LispEncapsulatedControl) msg); } if (msg instanceof LispMapRegister) { LispMapServer mapServer = new LispMapServer(); LispMapNotify mapNotify = mapServer.processMapRegister((LispMapRegister) msg); // try to remove the received map-register message from buffer ReferenceCountUtil.release(msg); ctx.writeAndFlush(mapNotify); } if (msg instanceof LispMapRequest) { LispMapResolver mapResolver = new LispMapResolver(); LispMapReply mapReply = (LispMapReply) mapResolver.processMapRequest((LispMapRequest) msg); // TODO: serialize mapReply message and write to channel } } @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()); ctx.close(); } /** * Extracts LISP message from encapsulated control message. * * @param ecm Encapsulated Control Message * @return extracted LISP message */ private LispMessage extractMapRequest(LispEncapsulatedControl ecm) { return ecm.getControlMessage(); } }