模拟MQTT订阅客户端【Qos暂时只支持1】
1.subClient
package com.MyMQTTServerAndClient.subscribeClient;
/*
* Description TODO
* On 4/27/2020 5:41 PM
*/
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.logging.LoggingHandler;
import org.eclipse.moquette.parser.netty.MQTTDecoder;
import org.eclipse.moquette.parser.netty.MQTTEncoder;
public class subClient {
public static void main(String[] args) {
subClient.startMqttClient();
}
public static void startMqttClient(){
EventLoopGroup group = new NioEventLoopGroup();
try {
Bootstrap b = new Bootstrap();
b.group(group);
b.channel(NioSocketChannel.class);
b.handler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel channel) throws Exception {
ChannelPipeline pipeline = channel.pipeline();
pipeline.addLast("log", new LoggingHandler());
pipeline.addLast("decoder", new MQTTDecoder());//解码
pipeline.addLast("encoder", new MQTTEncoder());//编码
pipeline.addLast("handler", new SubMQTTClientHandler());
}
});
ChannelFuture ch = b.connect("127.0.0.1", 7777).sync();
ch.channel().closeFuture().sync();
} catch (Exception e) {
e.printStackTrace();
group.shutdownGracefully();
}
}
}
2.SubMQTTClientHandler
package com.MyMQTTServerAndClient.subscribeClient;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.util.concurrent.Future;
import io.netty.util.concurrent.GenericFutureListener;
import io.netty.util.concurrent.ScheduledFuture;
import org.eclipse.moquette.proto.messages.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.UUID;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.stream.IntStream;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static java.util.concurrent.TimeUnit.SECONDS;
/**
*
* 备注:SubscribeMessage的Qos固定为1【服务端回复SubAckMessage】,如果设置为其他,会被编码器过滤掉
* 该类负责订阅话题
*/
public class SubMQTTClientHandler extends SimpleChannelInboundHandler<AbstractMessage> {
private static Logger logger = LoggerFactory.getLogger(SubMQTTClientHandler.class);
private String userName="admin";
private String passWord="password";
ScheduledFuture<?> scheduledFuture;//取消客户端心跳用
private static AtomicBoolean firstPingResp=new AtomicBoolean(true);//第一次ping通
// //Qos=0的待订阅的话题
// LinkedBlockingDeque<SubscribeMessage> zeroQosSubQueue=new LinkedBlockingDeque<>();
//Qos=1的待订阅的话题
LinkedBlockingDeque<SubscribeMessage> oneQosSubQueue=new LinkedBlockingDeque<>();
//Qos=1的订阅话题的ack
LinkedBlockingDeque<SubAckMessage> oneQosSubAckQueue=new LinkedBlockingDeque<>();
//已经发送订阅请求的map key为messageId value为该SubscribeMessage【用于处理Qos=1下,是否成功收到订阅成功ack】
ConcurrentHashMap<Integer,SubscribeMessage> alreadySendMap=new ConcurrentHashMap<>();
//已经成功订阅的话题【本地打印查看】
LinkedBlockingDeque<SubscribeMessage> alreadySubQueue=new LinkedBlockingDeque<>();
ExecutorService executorService;
List<java.util.concurrent.Future> FutureList=new ArrayList<>();
private Channel channel;
private Boolean running=new Boolean(true);
public SubMQTTClientHandler() {
executorService= Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
//订阅Qos=1的话题
java.util.concurrent.Future<?> future2 = executorService.submit(() -> {
while(running){
while (!oneQosSubQueue.isEmpty()) {
SubscribeMessage subscribeMessage = oneQosSubQueue.removeFirst();
Integer messageID = subscribeMessage.getMessageID();
//还没订阅过该topic消息,需要加入map
if (!alreadySendMap.containsKey(messageID)) {
alreadySendMap.put(messageID, subscribeMessage);
channel.writeAndFlush(subscribeMessage);
logger.info("subscribeMessage {} send to server success id {}, qos {}", subscribeMessage.subscriptions().get(0).getTopicFilter(),subscribeMessage.getMessageID(),subscribeMessage.getQos());
}
oneQosSubQueue.addLast(subscribeMessage);//此时还没成功收到服务端订阅成功的ack,不能移除该消息【在另一个线程中判断是否收到对应的ack来决定是否移除】
try {
//防止发送过快
SECONDS.sleep(1);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
});
//接受Qos=1订阅话题的ack
java.util.concurrent.Future<?> future3 = executorService.submit(() -> {
while(running){
while (!oneQosSubAckQueue.isEmpty()) {
SubAckMessage subAckMessage = oneQosSubAckQueue.removeFirst();
if (alreadySendMap.containsKey(subAckMessage.getMessageID())) {
//加入订阅成功队列
alreadySubQueue.add(alreadySendMap.get(subAckMessage.getMessageID()));
//收到订阅成功ack,需要从请求订阅队列移除该订阅消息
oneQosSubQueue.remove(alreadySendMap.get(subAckMessage.getMessageID()));
alreadySendMap.remove(subAckMessage.getMessageID());
} else {
logger.error("receive error SubAckMessage {}",
subAckMessage.getMessageID());
}
}
try {
//防止运行过快
MILLISECONDS.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
});
//打印成功订阅的话题
executorService.submit(()-> {
while (running) {
if(!alreadySubQueue.isEmpty()){
logger.info("alreadySubQueue queue size {}",alreadySubQueue.size());
alreadySubQueue.forEach((p)->{
logger.info("already sub topic is "+p.subscriptions().get(0).getTopicFilter());
});
}
try {
//防止运行过快
SECONDS.sleep(20);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
});
// FutureList.add(future1);
FutureList.add(future2);
FutureList.add(future3);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
logger.error("error message {}",cause);
}
@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
logger.info("client "+ctx.channel().remoteAddress()+" active");
//连接
ConnectMessage connectMessage = new ConnectMessage();
connectMessage.setProcotolVersion((byte) 3);
connectMessage.setQos(AbstractMessage.QOSType.LEAST_ONE);
connectMessage.setCleanSession(true);
connectMessage.setClientID(String.valueOf(UUID.randomUUID()));
connectMessage.setKeepAlive(60);
connectMessage.setWillFlag(false);
connectMessage.setUserFlag(true);
connectMessage.setUsername(this.userName);
connectMessage.setPasswordFlag(true);
connectMessage.setPassword(this.passWord);
ctx.writeAndFlush(connectMessage,ctx.newPromise().addListener((future)->{
if(future.cause()==null){
logger.info("send connectMessage success");
}else{
logger.error("send connectMessage error "+future.cause());
}
}));
}
@Override
public void channelInactive(ChannelHandlerContext ctx) throws Exception {
logger.error("channelInactive " +ctx.channel().remoteAddress());
boolean cancel = scheduledFuture.cancel(true);
logger.info("{} client canal heart beat {}",ctx.channel().localAddress(),cancel);
ctx.close(ctx.newPromise().addListener(new GenericFutureListener<Future<? super Void>>() {
@Override
public void operationComplete(Future<? super Void> future) throws Exception {
logger.info("channel {} close ",ctx.channel().localAddress());
}
}));
if(this.channel!=null){
channel=null;
}
//
running=false;
//
}
@Override
protected void channelRead0(ChannelHandlerContext ctx, AbstractMessage msg) throws Exception {
if(msg instanceof AbstractMessage){
byte messageType = msg.getMessageType();
switch(messageType){
case AbstractMessage.CONNACK:
processConnectAckResp(ctx,msg);
break;
case AbstractMessage.PINGRESP:
processPingResp();
break;
case AbstractMessage.PUBLISH:
processPublish(ctx,msg);
break;
case AbstractMessage.SUBACK:
processSubAck(ctx,msg);
break;
default:
logger.info("message type "+((AbstractMessage) msg).getMessageType());
break;
}
}
}
/**
* 收到服务端发来的该客户端话题订阅成功ack
* @param ctx
* @param msg
*/
private void processSubAck(ChannelHandlerContext ctx, AbstractMessage msg) {
SubAckMessage subAckMessage = (SubAckMessage) msg;
if(!oneQosSubAckQueue.contains(subAckMessage)){
oneQosSubAckQueue.addLast(subAckMessage);
logger.error("receive SubAckMessage from server id {}",subAckMessage.getMessageID());
}else{
logger.error("receive error SubAckMessage from server,id {}",subAckMessage.getMessageID());
}
}
/**
* 收到其他客户端发布的消息-由服务端发送来
* @param ctx
* @param msg
*/
private void processPublish(ChannelHandlerContext ctx, AbstractMessage msg) {
PublishMessage publishMessage = (PublishMessage) msg;
logger.info("receive topic from other client topic {} payload [{}]",publishMessage.getTopicName(),new String(publishMessage.getPayload().array()));
}
/**
* 发布的topic Qos=1时会收到pubAck
* @param ctx
* @param msg
*/
private void processPubAck(ChannelHandlerContext ctx, AbstractMessage msg) {
// PubAckMessage pubAckMessage = (PubAckMessage) msg;
// boolean result = oneQosSubAckQueue.offerLast(pubAckMessage);
// if(result==true){
// logger.info("receive PubAckMessage {} from MQTTServer,and insert queue success",pubAckMessage.getMessageID());
// }else{
// logger.error("failed insert PubAckMessage {} into queue",pubAckMessage.getMessageID());
// }
}
//第一次接收到服务端pingResp后才会发布主题或者订阅主题
private void processPingResp() {
if(firstPingResp.get()){
logger.debug("first receive ping response , start subscribe topic" );
/**
* qos=1只能是1,SubscribeMessage构造器设置
*/
subscribeTopics("mqttClient/topicTwo2");
subscribeTopics("mqttClient/topicTwo3");
subscribeTopics("mqttClient/topicTwo4");
firstPingResp.set(false);
}else{
logger.debug("ping response");
}
}
/**
* 订阅话题【目前Qos支持1】 这里我们默认只能订阅一个话题
*/
private void subscribeTopics(String topic) {
SubscribeMessage subscribeMessage = new SubscribeMessage();
/**
* 只能是qos=1,SubscribeMessage构造器设置
*/
subscribeMessage.addSubscription(new SubscribeMessage.Couple((byte) AbstractMessage.QOSType.LEAST_ONE.ordinal(),topic));
subscribeMessage.setMessageID(new Random().nextInt(10000));
boolean offer = oneQosSubQueue.offer(subscribeMessage);
if(offer){
logger.info("subscribeMessage {} insert zeroQosSubQueue success is {}",subscribeMessage.subscriptions().get(0).getTopicFilter(),subscribeMessage.getMessageID());
}
}
// /**
// * 发布主题【Qos目前只支持0、1】
// * @param topic
// * @param qos
// */
// private void publishTopic(String topic,AbstractMessage.QOSType qos) {
// //这个字段需要设置,否者无法发送消息
// PublishMessage publishMessage = new PublishMessage();
// publishMessage.setTopicName(topic);
// publishMessage.setQos(qos);
// int random = new Random().nextInt(10000);//<2^32-1
// /**
// * qos=0情况下服务端接收到数据后MessageID会被设置为null【应该是编解码的时候被设置】
// */
// publishMessage.setMessageID(random);
// publishMessage.setRetainFlag(false);
// publishMessage.setPayload(ByteBuffer.wrap("I am payload".getBytes()));
// if(qos== AbstractMessage.QOSType.MOST_ONE){
// boolean offer = zeroQosPubQueue.offer(publishMessage);
// if(offer){
// logger.info("publishMessage {} insert zeroQosPubQueue success ",publishMessage.getTopicName());
// }
// }else if(qos== AbstractMessage.QOSType.LEAST_ONE){
// boolean offer = oneQosSubQueue.offer(publishMessage);
// if(offer){
// logger.info("publishMessage {} insert oneQosSubQueue success ",publishMessage.getTopicName());
// }
// }
// }
private void processConnectAckResp(ChannelHandlerContext ctx, Object msg) {
ConnAckMessage ackMessage = (ConnAckMessage) msg;
if(ackMessage.getReturnCode()==(byte)0){
channel=ctx.channel();
logger.info("get connectAck success, start heart beat" );
//存
// ctx.channel().attr(MyConstants.pingKey).setIfAbsent("firstPing");
// 定时心跳任务
scheduledFuture = ctx.channel().eventLoop().scheduleAtFixedRate(() -> {
PingReqMessage pingReqMessage = new PingReqMessage();
pingReqMessage.setQos(AbstractMessage.QOSType.MOST_ONE);//心跳暂时MOST_ONE(0)
ctx.writeAndFlush(pingReqMessage, ctx.newPromise().addListener((future) -> {
if (future.cause() == null) {
logger.info("send heartBeat success");
} else {
logger.error("send heartBeat error");
}
}));
}, 2, 55, SECONDS);
}else if(ackMessage.getReturnCode()==(byte)4){
logger.error("get connectAck failed, cannot heart beat,username or password" );//
ctx.close();
}
}
@Override
public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
ctx.fireUserEventTriggered(evt);
}
}
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