netty使用
pom.xml
<dependency> <groupId>io.netty</groupId> <artifactId>netty-all</artifactId> <version>4.1.25.Final</version> </dependency> <dependency> <groupId>cn.hutool</groupId> <artifactId>hutool-all</artifactId> <version>5.3.3</version> </dependency>
一、创建连接缓存对象
package com.example.demo.netty; import cn.hutool.core.date.DateUtil; import io.netty.channel.socket.SocketChannel; import lombok.Data; import java.sql.Timestamp; import java.util.Date; /** * netty缓存对象 */ @Data public class NettyCacheInfo { /** * ip:port */ private String ipPort; /** * netty连接对象 */ private SocketChannel socketChannel; /** * 连接状态 */ private boolean connected; /** * 活动时间 */ private Timestamp activeTime; /** * 活动时间格式化 */ private String activeTimeFormat; public NettyCacheInfo() { } public void setActiveTime(Timestamp activeTime) { this.activeTime = activeTime; this.activeTimeFormat= DateUtil.format(new Date(activeTime.getTime()),"yyyy-MM-dd HH:mm:ss"); } }
二、创建netty客户端
package com.example.demo.netty; import io.netty.bootstrap.Bootstrap; import io.netty.channel.*; import io.netty.channel.nio.NioEventLoopGroup; import io.netty.channel.socket.SocketChannel; import io.netty.channel.socket.nio.NioSocketChannel; import lombok.extern.slf4j.Slf4j; import java.sql.Timestamp; import java.util.HashMap; import java.util.Map; /** * netty客户端 */ @Slf4j public class NettyClient { private NettyClient(){} /** * Netty连接信息缓存 * key-> host:port * value-> nettyInfo */ public static Map<String,NettyCacheInfo> channels = new HashMap<>(); /** * 失败的连接缓存 */ public static Map<String,NettyCacheInfo> failChannels = new HashMap<>(); /** * netty连接池 */ static EventLoopGroup eventLoopGroup = new NioEventLoopGroup(); static Bootstrap bootstrap = null; /** * netty回调类 */ static NettyHandler nettyHandler; /** * 塞入回调处理类 * @param handler */ public static void setNettyHandler(NettyHandler handler){ nettyHandler = handler; } /** * 初始化BootStrap * @param eventLoopGroup * @return */ public static final Bootstrap getBootstrap(EventLoopGroup eventLoopGroup){ if(bootstrap==null){ bootstrap = new Bootstrap(); bootstrap.group(eventLoopGroup) .channel(NioSocketChannel.class) .option(ChannelOption.RCVBUF_ALLOCATOR,new AdaptiveRecvByteBufAllocator(20480,20480,65536)) .option(ChannelOption.SO_KEEPALIVE, true) .option(ChannelOption.TCP_NODELAY, true) .option(ChannelOption.CONNECT_TIMEOUT_MILLIS,5*1000) .handler(new ChannelInitializer<SocketChannel>() { @Override protected void initChannel(SocketChannel socketChannel) throws Exception { socketChannel.pipeline() .addLast("encoder", new RpcDecoder()) .addLast(nettyHandler); } }); } return bootstrap; } /** * 获取连接对象 * @param ipPort */ public static NettyCacheInfo getNettyCacheInfo(String ipPort){ NettyCacheInfo nettyInfo = null; if(channels.containsKey(ipPort)){ nettyInfo = channels.get(ipPort); }else{ log.error("地址:【{}】暂无连接",ipPort); } return nettyInfo; } /** * 单独连接某一个装置 * @param info */ public static void connect(NettyCacheInfo info){ String ipPort = info.getIpPort(); if(!channels.containsKey(ipPort)){ //先添加缓存,方便handler中处理 info.setConnected(false); String[] arr = ipPort.split(":"); bootstrap.remoteAddress(arr[0],Integer.parseInt(arr[1])); //连接初始化监听 bootstrap.connect().addListener((ChannelFutureListener) futureListener -> { if (futureListener.isSuccess()) { log.info("监听:{}连接成功", ipPort); info.setActiveTime(new Timestamp(System.currentTimeMillis())); info.setSocketChannel((SocketChannel) futureListener.channel()); info.setConnected(true); channels.put(ipPort,info); } else { failChannels.put(ipPort,info); log.info("监听:{}连接失败", ipPort); } }); }else{ log.info("地址:{}连接已存在",ipPort); } } }
创建数据解码器
package com.example.demo.netty; import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelHandlerContext; import io.netty.handler.codec.ByteToMessageDecoder; import java.util.List; /** * Netty消息体解码器 * 自定义 */ public class RpcDecoder extends ByteToMessageDecoder { @Override protected void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) { int dataLength = in.readableBytes(); byte[] data = new byte[dataLength]; in.readBytes(data); String str = bytesToHex(data, dataLength); out.add(str); } /** * 16进制转String * @param bytes * @param counts * @return */ private String bytesToHex(byte[] bytes, int counts){ StringBuffer sbu = new StringBuffer(); for (int i = 0; i < counts/* bytes.length */; i++) { int val = new Byte(bytes[i]).intValue(); String str = Integer.toHexString(val & 0xff); if (str.length() == 1) { str = "0" + str; } sbu.append(str); if (i != counts - 1) { sbu.append(" "); } } return sbu.toString().toUpperCase(); } }
三、创建netty回调类
package com.example.demo.netty; import io.netty.channel.ChannelHandler; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.EventLoop; import io.netty.channel.SimpleChannelInboundHandler; import lombok.extern.slf4j.Slf4j; import org.springframework.stereotype.Component; import java.net.InetSocketAddress; import java.sql.Timestamp; /** * Netty回调类 */ @Slf4j @ChannelHandler.Sharable @Component public class NettyHandler extends SimpleChannelInboundHandler<String> { @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { try { //获取连接信息 ip,port InetSocketAddress address=(InetSocketAddress)ctx.channel().remoteAddress(); String host = address.getHostString(); int port = address.getPort(); log.info("....客户端连接成功....连接地址为:"+host+":"+port); //获取netty缓存 NettyCacheInfo cacheInfo = NettyClient.getNettyCacheInfo(host + ":" + port); if(cacheInfo!=null) { cacheInfo.setActiveTime(new Timestamp(System.currentTimeMillis())); } ctx.fireChannelActive(); } catch (Exception e) { log.error("channelActive:"+e.getMessage()); } } @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { try { //获取连接信息 ip,port InetSocketAddress address=(InetSocketAddress)ctx.channel().remoteAddress(); String host = address.getHostString(); int port = address.getPort(); log.info("....客户端连接断开....连接地址为:"+host+":"+port); //获取netty缓存 NettyCacheInfo cacheInfo = NettyClient.getNettyCacheInfo(host + ":" + port); if(cacheInfo!=null) { cacheInfo.setActiveTime(new Timestamp(System.currentTimeMillis())); } NettyClient.channels.remove(host+":"+port); NettyClient.failChannels.put(host+":"+port,cacheInfo); final EventLoop eventLoop = ctx.channel().eventLoop(); } catch (Exception e) { log.error("channelInactive:"+e.getMessage()); } } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { try { //获取连接信息 ip,port InetSocketAddress address=(InetSocketAddress)ctx.channel().remoteAddress(); String host = address.getHostString(); int port = address.getPort(); log.info("....客户端连接异常....连接地址为:{}:{}...异常信息为:{}",host,port,ctx.channel().id().asShortText()); //获取netty缓存 NettyCacheInfo cacheInfo = NettyClient.getNettyCacheInfo(host + ":" + port); if(cacheInfo!=null) { cacheInfo.setActiveTime(new Timestamp(System.currentTimeMillis())); } NettyClient.channels.remove(host + ":" + port); NettyClient.failChannels.put(host+":"+port,cacheInfo); } catch (Exception e) { log.error("exceptionCaught:"+e.getMessage()); } } /** * 接受到消息后的方法 * @param ctx * @param s * @throws Exception */ @Override protected void channelRead0(ChannelHandlerContext ctx, String s) throws Exception { try { //获取连接信息 ip,port InetSocketAddress address=(InetSocketAddress)ctx.channel().remoteAddress(); String host = address.getHostString(); int port = address.getPort(); log.debug("接收到地址:【{}:{}】的数据:{}",host,port,s); //获取netty缓存 NettyCacheInfo cacheInfo = NettyClient.getNettyCacheInfo(host + ":" + port); cacheInfo.setActiveTime(new Timestamp(System.currentTimeMillis())); //TODO:准备处理数据 } catch (Exception e) { log.error("channelRead0:"+e.getMessage()); } } }
四、创建配置加载类,在项目启动时进行加载
package com.example.demo.netty; import lombok.extern.slf4j.Slf4j; import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Component; import javax.annotation.PostConstruct; import javax.annotation.Resource; import java.util.Map; /** *netty配置类 */ @Slf4j @Component public class NettyConfig { @Resource NettyHandler nettyHandler; /** * 初始化加载时注入handler回调类 */ @PostConstruct public void init(){ NettyClient.bootstrap =NettyClient.getBootstrap(NettyClient.eventLoopGroup); NettyClient.setNettyHandler(nettyHandler); log.info("进行Netty初始化加载"); } /** * 初始化连接 */ @Scheduled(cron = "0 0/5 * * * ?") public void connectDevice(){ log.info("删除长时间不活动的装置终端"); long curl = System.currentTimeMillis(); for(Map.Entry<String,NettyCacheInfo> entry:NettyClient.channels.entrySet()){ String ipPort = entry.getKey(); NettyCacheInfo info = entry.getValue(); long actt = info.getActiveTime().getTime(); log.info("地址信息:{},当前时间:{},活动时间{}",ipPort,curl,actt); //大于5分钟未响应 if(curl-actt>5*60*1000){ log.info("地址:{}连接5分钟无活动,剔除连接",ipPort); info.getSocketChannel().close(); NettyClient.channels.remove(ipPort); info.setConnected(false); NettyClient.failChannels.put(ipPort,info); } } } }
五、创建消息发送工具类
package com.example.demo.netty; import io.netty.buffer.ByteBuf; import io.netty.channel.ChannelFutureListener; import io.netty.channel.socket.SocketChannel; import lombok.extern.slf4j.Slf4j; /** * 通过netty对象发送数据 */ @Slf4j public class NettyWrite { /** * 发送数据-十六进制数据 */ public static void writeAndFlushBy(NettyCacheInfo cacheInfo, String hexString) { //获取连接对象 SocketChannel channel = cacheInfo.getSocketChannel(); if (channel == null || !channel.isActive() || !channel.isOpen() || !channel.isWritable()) { // 获取不到串口，将任务停止删掉 throw new NullPointerException("未获取到网口连接"); } log.info("{} 开始下发报文数据！", cacheInfo.getIpPort()); try { byte[] bytes = hexStrToBytes(hexString); ByteBuf buffer = channel.alloc().buffer(); ByteBuf byteBuf = buffer.writeBytes(bytes); channel.writeAndFlush(byteBuf).addListener((ChannelFutureListener) future -> { if (future.isSuccess()) { log.info("{} 下发报文成功！", cacheInfo.getIpPort()); } else { throw new Exception("下发报文失败"); } }); } catch (Exception e) { throw e; } } /** * 十六进制字符串转为数组 * @param hexStr * @return */ private static byte[] hexStrToBytes(String hexStr) { String[] hexs = splitString(hexStr); byte[] hexBytes = new byte[hexs.length]; for (int i = 0; i < hexs.length; i++) { hexBytes[i] = hexToByte(hexs[i]); } return hexBytes; } private static byte hexToByte(String arg) { int val = Integer.valueOf(arg, 16).intValue(); byte c = (byte) (val & 0xff); return c; } private static String[] splitString(String messageContent) { messageContent = messageContent.replace(" ", ""); int leng = messageContent.length() / 2; String[] messageContentArray = new String[leng]; int beginIndex = 0; for (int i = 0; i < leng; i++) { int endIndex = beginIndex + 2; messageContentArray[i] = messageContent.substring(beginIndex, endIndex); beginIndex += 2; } return messageContentArray; } }
使用方法:
List<String> addressList = new ArrayList<>(); addressList.add("192.168.0.0.1:111"); addressList.add("192.168.0.0.2:111"); addressList.add("192.168.0.0.3:111"); addressList.add("192.168.0.0.4:111"); addressList.add("192.168.0.0.5:111"); addressList.add("192.168.0.0.6:111"); for (String address:addressList) { //创建缓存对象 NettyCacheInfo nettyCacheInfo = new NettyCacheInfo(); nettyCacheInfo.setIpPort(address); nettyCacheInfo.setConnected(false); //进行连接 NettyClient.connect(nettyCacheInfo); } //发送数据 String hexString = "01 A1 00 B2"; NettyWrite.writeAndFlushBy(NettyClient.getNettyCacheInfo("192.168.0.0.1:111"),hexString);
