Java tutorial
/* * This file is part of the Yildiz-Engine project, licenced under the MIT License (MIT) * * Copyright (c) 2018 Grgory Van den Borre * * More infos available: https://www.yildiz-games.be * * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated * documentation files (the "Software"), to deal in the Software without restriction, including without * limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies * of the Software, and to permit persons to whom the Software is furnished to do so, * subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all copies or substantial * portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE * WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS * OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * */ package be.yildizgames.module.network.netty.client; import be.yildizgames.module.network.client.ClientCallBack; import be.yildizgames.module.network.protocol.MessageSeparation; import be.yildizgames.module.network.protocol.MessageWrapper; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; import org.slf4j.LoggerFactory; import java.util.ArrayList; import java.util.List; /** * @author Grgory Van den Borre */ public abstract class AbstractClientMessageHandler<T> extends SimpleChannelInboundHandler<T> { private static final org.slf4j.Logger LOGGER = LoggerFactory.getLogger(AbstractClientMessageHandler.class); private static final int BUFFER_SIZE = 1024; /** * Used to store an incomplete message waiting for its other parts. */ private final List<String> cutMessage = new ArrayList<>(); private final ClientCallBack callBack; AbstractClientMessageHandler(ClientCallBack cb) { super(); this.callBack = cb; } @Override public final void channelInactive(final ChannelHandlerContext ctx) throws Exception { super.channelInactive(ctx); this.callBack.connectionFailed(); LOGGER.info("Netty channel closed: {}", ctx.channel()); } @Override public final void exceptionCaught(final ChannelHandlerContext ctx, final Throwable e) { LOGGER.error("Exception", e); ctx.channel().close(); callBack.connectionLost(); } void handleMessage(String message) { if (message.endsWith(MessageSeparation.MESSAGE_END)) { if (!this.cutMessage.isEmpty()) { StringBuilder sb = new StringBuilder(BUFFER_SIZE); this.cutMessage.forEach(sb::append); sb.append(message); this.processMessage(sb.toString()); this.cutMessage.clear(); } else { this.processMessage(message); } } else { this.cutMessage.add(message); } } /** * Process the message to cut it in readable message. * * @param message Message to process. */ private void processMessage(final String message) { String messageWithoutStartChar = message.replaceAll(MessageSeparation.MESSAGE_BEGIN, ""); final String[] messages = messageWithoutStartChar.split(MessageSeparation.MESSAGE_END); for (final String c : messages) { MessageWrapper current = new MessageWrapper(c); callBack.messageReceived(current); } } }