java调用MQTT的后台代码 和 js调用MQTT

一、java后台调用MQTT

准备工作：需要导入的jar包

 <!-- mqtt依赖包-->
 <dependency>
     <groupId>org.fusesource.mqtt-client</groupId>
     <artifactId>mqtt-client</artifactId>
     <version>1.14</version>
 </dependency>

1.发布消息

import org.fusesource.hawtbuf.AsciiBuffer;
import org.fusesource.hawtbuf.UTF8Buffer;
import org.fusesource.mqtt.client.Future;
import org.fusesource.mqtt.client.FutureConnection;
import org.fusesource.mqtt.client.MQTT;
import org.fusesource.mqtt.client.QoS;
import java.util.LinkedList;

/**
  * MQTT消息发送
  * @param topics  主题
  * @param data 发送内容
  * @throws Exception
  */
public static void checkMQTT(String topics,String data) throws Exception {
        String user = env("ACTIVEMQ_USER", "admin"); //mqtt账号
        String password = env("ACTIVEMQ_PASSWORD", "admin"); //mqtt密码
        String host = env("ACTIVEMQ_HOST", "localhost");  //地址
        int port = Integer.parseInt(env("ACTIVEMQ_PORT", "1883"));  //端口号

        String DATA = data;//发送的信息
        String body = "";
        for( int i=0; i < DATA.length(); i ++) {
            body += DATA.charAt(i%DATA.length());
        }

        UTF8Buffer bodys = new UTF8Buffer(body); //进行编码转换，防止无法发送中文
        MQTT mqtt = new MQTT();
        mqtt.setHost(host, port);
        mqtt.setUserName(user);
        mqtt.setPassword(password);

        FutureConnection connection = mqtt.futureConnection();
        connection.connect().await();

        final LinkedList<Future<Void>> queue = new LinkedList<Future<Void>>();
        UTF8Buffer topic = new UTF8Buffer(topics); //对主题进行编码转换，防止中文异常

         queue.add(connection.publish(topic, new AsciiBuffer(bodys), QoS.AT_LEAST_ONCE, false)); //发送mqtt

        while( !queue.isEmpty() ) {
            queue.removeFirst().await();
        }

        connection.disconnect().await();


}

private static String env(String key, String defaultValue) {
        String rc = System.getenv(key);
        if( rc== null )
            return defaultValue;
        return rc;
}

2.订阅消息

public static void getTopic(String topic) throw Exception{

    String user = env("ACTIVEMQ_USER", "admin");
    String password = env("ACTIVEMQ_PASSWORD", "password");
    String host = env("ACTIVEMQ_HOST", "localhost");
    int port = Integer.parseInt(env("ACTIVEMQ_PORT", "1883"));

    MQTT mqtt = new MQTT();
    mqtt.setHost(host, port);
    mqtt.setUserName(user);
    mqtt.setPassword(password);

    final CallbackConnection connection = mqtt.callbackConnection();

    connection.listener(new org.fusesource.mqtt.client.Listener() {
        public void onConnected() {
        }
        public void onDisconnected() {
        }
        public void onFailure(Throwable value) {
            value.printStackTrace();
            
        }


        public void onPublish(UTF8Buffer utfTopic, Buffer msg, Runnable ack) {
             String body = msg.utf8().toString();
             if( "SHUTDOWN".equals(body)) {
                 long diff = System.currentTimeMillis() - start;
                 System.out.println(String.format("Received %d in %.2f seconds", count, (1.0*diff/1000.0)));
                 connection.disconnect(new Callback<Void>() {
                     @Override
                     public void onSuccess(Void value) {
                            
                     }
                     @Override
                     public void onFailure(Throwable value) {
                         value.printStackTrace();
                           
                    }
                 });
             } else {
                 if( count == 0 ) {
                     start = System.currentTimeMillis();
                 }
                 if( count % 1000 == 0 ) {
                     System.out.println(String.format("Received %d messages.", count));
                 }
                 count ++;
             }
                ack.run();
       }


    });

    connection.connect(new Callback<Void>() {
        @Override
        public void onSuccess(Void value) {
        Topic[] topics = {new Topic(topic, QoS.AT_LEAST_ONCE)};
        connection.subscribe(topics, new Callback<byte[]>() {
            public void onSuccess(byte[] qoses) {
            }
            public void onFailure(Throwable value) {
                value.printStackTrace();
                        
            }
            });
        }

        @Override
        public void onFailure(Throwable value) {
             value.printStackTrace();
               
       }
    });



}

二、前台页面js调用MQTT

需要引入的js

<script src="js/mqttws31.js"></script>

1.页面接收 和 发送mqtt

//连接mqtt
var client,destination;
function linkMQTT() {
    var host = "localhost";
    var port = "61614";
    var clientId ="example-68312";
    var user ="admin";
    var password ="admin";
   
    client = new Messaging.Client(host, Number(port), clientId);

    client.onConnect = onConnect;

    client.onMessageArrived = onMessageArrived;
    client.onConnectionLost = onConnectionLost;

    client.connect({
        userName:user,
        cleanSession:true,
        password:password,
        onSuccess:onConnect,
        onFailure:onFailure
     });
     return false;
}

//接收消息
var onConnect = function(frame) {
    client.subscribe('00000001010042'); //订阅主题
    client.subscribe('00000001010001');
}

//失败的操作
function onFailure(failure) {
    
   alert(failure.errorMessage);
}

//订阅成功的操作
function onMessageArrived(message) {

   alert(message.payloadString);   
}

function onConnectionLost(responseObject) {
   if (responseObject.errorCode !== 0) {
       alert(client.clientId + ": " + responseObject.errorCode + "\n");
   }
}

//发送消息
funcation sendMessage(text) {
     message = new Messaging.Message(text);
     message.destinationName = '00000001010001';
     client.send(message);

     message = new Messaging.Message(text);
     message.destinationName = '00000001010042';
     client.send(message);

}