MQTT服务器实现:
首先安装服务器z这里服务器使用(EMQ)
参考文档(http://www.emqtt.com/docs/v2/install.html#tcp):
下载地址以下:
http://www.emqtt.com/downloads
不一样服务器下载不一样版本
下载完成后解压,修改默认配置文件html
默认端口
端口 用途
1883 MQTT协议端口
8883 MQTT(SSL)端口
8083 MQTT(WebSocket), HTTP API端口
18083 Dashboard管理控制台端口
emqtt上述端口配置,可经过文件etc/emq.conf配置文件的listeners段落设置。
listener.tcp.external = 0.0.0.0:1883
java
其中Dashboard 端口须要在插件中修改:
web
修改完成后
使用cmd 命名
进入解压缩后的目录 cd /d D:\services\mqtt\emqttd\bin
而后执行 emqttd console
后台开启服务:
emqttd start
中止服务:
emqttd stop
到此MQTT服务端安装完成
能够经过http端口访问:
http://120.55.60.217:1888/
该端口是须要本身配置Dashboard端口服务器
使用JAVA来进行测试:
引入mavensession
<dependency> <groupId>org.eclipse.paho</groupId> <artifactId>org.eclipse.paho.client.mqttv3</artifactId> <version>1.2.1</version> </dependency>
服务端代码:eclipse
package com.roctec.rocteccloudtest; import org.eclipse.paho.client.mqttv3.MqttClient; import org.eclipse.paho.client.mqttv3.MqttConnectOptions; import org.eclipse.paho.client.mqttv3.MqttDeliveryToken; import org.eclipse.paho.client.mqttv3.MqttException; import org.eclipse.paho.client.mqttv3.MqttMessage; import org.eclipse.paho.client.mqttv3.MqttPersistenceException; import org.eclipse.paho.client.mqttv3.MqttTopic; import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence; /** * Title:Server 这是发送消息的服务端 * Description: 服务器向多个客户端推送主题,即不一样客户端可向服务器订阅相同主题 * @author rao */ public class ServerMQTT { //tcp://MQTT安装的服务器地址:MQTT定义的端口号 public static final String HOST = "tcp://120.55.60.217:12111"; //定义一个主题 public static final String TOPIC = "pos_message_all"; //定义MQTT的ID,能够在MQTT服务配置中指定 private static final String clientid = "server11"; private MqttClient client; private MqttTopic topic11; private String userName = "paho"; //非必须 private String passWord = ""; //非必须 private MqttMessage message; /** * 构造函数 * @throws MqttException */ public ServerMQTT() throws MqttException { // MemoryPersistence设置clientid的保存形式,默认为之内存保存 client = new MqttClient(HOST, clientid, new MemoryPersistence()); connect(); } /** * 用来链接服务器 */ private void connect() { MqttConnectOptions options = new MqttConnectOptions(); options.setCleanSession(false); options.setUserName(userName); options.setPassword(passWord.toCharArray()); // 设置超时时间 options.setConnectionTimeout(10); // 设置会话心跳时间 options.setKeepAliveInterval(20); try { client.setCallback(new PushCallback()); client.connect(options); topic11 = client.getTopic(TOPIC); } catch (Exception e) { e.printStackTrace(); } } /** * * @param topic * @param message * @throws MqttPersistenceException * @throws MqttException */ public void publish(MqttTopic topic , MqttMessage message) throws MqttPersistenceException, MqttException { MqttDeliveryToken token = topic.publish(message); token.waitForCompletion(); System.out.println("message is published completely! " + token.isComplete()); } /** * 启动入口 * @param args * @throws MqttException */ public static void main(String[] args) throws MqttException { ServerMQTT server = new ServerMQTT(); server.message = new MqttMessage(); server.message.setQos(1); //保证消息能到达一次 server.message.setRetained(true); server.message.setPayload("这是推送消息的内容".getBytes()); server.publish(server.topic11 , server.message); System.out.println(server.message.isRetained() + "------ratained状态"); } }
消息回调代码:maven
package com.roctec.rocteccloudtest; import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken; import org.eclipse.paho.client.mqttv3.MqttCallback; import org.eclipse.paho.client.mqttv3.MqttMessage; /** * 发布消息的回调类 * * 必须实现MqttCallback的接口并实现对应的相关接口方法CallBack 类将实现 MqttCallBack。 * 每一个客户机标识都须要一个回调实例。在此示例中,构造函数传递客户机标识以另存为实例数据。 * 在回调中,将它用来标识已经启动了该回调的哪一个实例。 * 必须在回调类中实现三个方法: * * public void messageArrived(MqttTopic topic, MqttMessage message)接收已经预订的发布。 * * public void connectionLost(Throwable cause)在断开链接时调用。 * * public void deliveryComplete(MqttDeliveryToken token)) * 接收到已经发布的 QoS 1 或 QoS 2 消息的传递令牌时调用。 * 由 MqttClient.connect 激活此回调。 * */ public class PushCallback implements MqttCallback { @Override public void connectionLost(Throwable cause) { // 链接丢失后,通常在这里面进行重连 System.out.println("链接断开,能够作重连"); } @Override public void deliveryComplete(IMqttDeliveryToken token) { System.out.println("deliveryComplete---------" + token.isComplete()); } @Override public void messageArrived(String topic, MqttMessage message) throws Exception { // subscribe后获得的消息会执行到这里面 System.out.println("接收消息主题 : " + topic); System.out.println("接收消息Qos : " + message.getQos()); System.out.println("接收消息内容 : " + new String(message.getPayload())); } }
客户端测试代码:tcp
package com.roctec.rocteccloudtest; import java.util.concurrent.ScheduledExecutorService; import org.eclipse.paho.client.mqttv3.MqttClient; import org.eclipse.paho.client.mqttv3.MqttConnectOptions; import org.eclipse.paho.client.mqttv3.MqttException; import org.eclipse.paho.client.mqttv3.MqttTopic; import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence; /** * 模拟一个客户端接收消息 * @author rao * */ public class ClientMQTT { public static final String HOST = "tcp://120.55.60.217:12111"; public static final String TOPIC1 = "NJGN/MCU32/00018"; private static final String clientid = "client11"; private MqttClient client; private MqttConnectOptions options; private String userName = "admin"; //非必须 private String passWord = "password"; //非必须 @SuppressWarnings("unused") private ScheduledExecutorService scheduler; private void start() { try { // host为主机名,clientid即链接MQTT的客户端ID,通常以惟一标识符表示,MemoryPersistence设置clientid的保存形式,默认为之内存保存 client = new MqttClient(HOST, clientid, new MemoryPersistence()); // MQTT的链接设置 options = new MqttConnectOptions(); // 设置是否清空session,这里若是设置为false表示服务器会保留客户端的链接记录,设置为true表示每次链接到服务器都以新的身份链接 options.setCleanSession(false); // 设置链接的用户名 options.setUserName(userName); // 设置链接的密码 options.setPassword(passWord.toCharArray()); // 设置超时时间 单位为秒 options.setConnectionTimeout(10); // 设置会话心跳时间 单位为秒 服务器会每隔1.5*20秒的时间向客户端发送个消息判断客户端是否在线,但这个方法并无重连的机制 options.setKeepAliveInterval(20); // 设置回调 client.setCallback(new PushCallback()); MqttTopic topic = client.getTopic(TOPIC1); //setWill方法,若是项目中须要知道客户端是否掉线能够调用该方法。设置最终端口的通知消息 //遗嘱 options.setWill(topic, "close".getBytes(), 2, true); client.connect(options); //订阅消息 int[] Qos = {1}; String[] topic1 = {TOPIC1}; client.subscribe(topic1, Qos); } catch (Exception e) { e.printStackTrace(); } } public static void main(String[] args) throws MqttException { ClientMQTT client = new ClientMQTT(); client.start(); } }
运行以下:ide