MQTT服务器搭建（二）通信及保存文件到MySql数据库

步骤

本文使用Mybatis，如果你不会，那就照猫画虎吧

1、搭建数据库

CREATE DATABASE `iot`;

USE `iot`;

DROP TABLE IF EXISTS `messages`;

CREATE TABLE `messages` (
                         `id` INT(10) NOT NULL AUTO_INCREMENT COMMENT ‘信息id‘,
                         `topic` VARCHAR(100) NOT NULL COMMENT ‘topic‘,
                         `temperature` int(3) NOT NULL COMMENT ‘温度‘,
                         `himidity` int(3) NOT NULL COMMENT ‘湿度‘,
                         `PM2_5` int(3) NOT NULL COMMENT ‘PM2_5‘,
                         `fan` int(1) NOT NULL COMMENT ‘风扇状态‘,
                         `light` int(1) NOT NULL COMMENT ‘灯光状态‘,
                         `power` int(1) NOT NULL COMMENT ‘机器状态‘,
                         `msg` VARCHAR(1000) NOT NULL COMMENT ‘消息‘,
                         primary key(`id`)
) ENGINE=INNODB DEFAULT CHARSET=utf8;

2、连接数据库

然后在IDEA边框上会有一个Database，点开它

3、IDEA新建一个普通的maven项目，在pom.xml中导入maven依赖

如果你的maven不能自动导入，建议去看看maven配置

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>MyBatis-study</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
    	<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  	</properties>
    
    <!--导入依赖-->
    <dependencies>
        <!--mysql驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <!--junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        
        <!-- https://mvnrepository.com/artifact/org.eclipse.paho/org.eclipse.paho.client.mqttv3 -->
		<dependency>
 		    <groupId>org.eclipse.paho</groupId>
  		    <artifactId>org.eclipse.paho.client.mqttv3</artifactId>
    		<version>1.2.4</version>
		</dependency>
    </dependencies>
    
    <!--build中配置resources，来放置我们资源导出失败的问题-->
    <build>
        <resources>
            <resource>
                <directory>src/main/resource</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>true</filtering>
            </resource>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                <include>**/*.properties</include>
                <include>**/*.xml</include>
            </includes>
            <filtering>true</filtering>
            </resource>
        </resources>
    </build>
</project>

4、创建mybatis的核心配置文件mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
		PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
		"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
	<settings>
		<setting name="logImpl" 	value="STDOUT_LOGGING"/>
	</settings>
	<!--配置数据源，交给Spring去做-->
	<typeAliases>
		<package name="com.iot.pojo"/>
	</typeAliases>

	<environments default="development">
		<environment id="development">
			<transactionManager type="JDBC"/><!--事务管理-->
			<dataSource type="POOLED">
				<property name="driver" value="com.mysql.jdbc.Driver"/>
				<property name="url" value="jdbc:mysql://localhost:3306/iot?useSSL=true&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
				<property name="username" value="root"/>
				<property name="password" value="root"/>
			</dataSource>
		</environment>
	</environments>
	<mappers>
		<mapper class="com.iot.dao.MessagesMapper"/>
	</mappers>

</configuration>

5、编写mybatis工具类MyBatisUtils.java

package com.iot.utils;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;

//SqlSessionFactory --> SqlSession
public class MyBatisUtils {
    private static SqlSessionFactory sqlSessionFactory;
    static {

        try {
            //使用mybatis第一步，获取SqlSessionFactory对象
            String resource = "mybatis-config.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    //既然有了 SqlSessionFactory，顾名思义，我们可以从中获得 SqlSession 的实例。
    // SqlSession 提供了在数据库执行 SQL 命令所需的所有方法。
    // 你可以通过 SqlSession 实例来直接执行已映射的 SQL 语句。
    public static SqlSession getSqlSession(){
        return sqlSessionFactory.openSession();
    }
}

6、创建实体类Messages.java

package com.iot.pojo;

public class Messages {
    private int id;
    private String topic;
    private int temperature;
    private int himidity;
    private int PM2_5;
    private int fan;
    private int light;
    private int power;
    private String msg;

    public Messages(int id, String topic, int temperature, int himidity, int PM2_5, int fan, int light, int power, String msg) {
        this.id = id;
        this.topic = topic;
        this.temperature = temperature;
        this.himidity = himidity;
        this.PM2_5 = PM2_5;
        this.fan = fan;
        this.light = light;
        this.power = power;
        this.msg = msg;
    }
    
}

7、创建Dao接口MessageMapper.java

package com.iot.dao;

import com.iot.pojo.Messages;

public interface MessagesMapper {
    //添加订阅信息到库
    public int addMes(Messages messages);

    //获取数据库中数据的数量
    public int getCount();
}

8、创建实现接口的配置文件MessageMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
		PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
		"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.iot.dao.MessagesMapper">

	<insert id="addMes" parameterType="Messages">
		insert into iot.messages(id, topic, temperature, himidity, PM2_5, fan, light, power, msg)
		VALUES(#{id},#{topic},#{temperature},#{himidity},#{PM2_5},#{fan},#{light},#{power},#{msg});
	</insert>

	<select id="getCount" resultType="int">
		select count(*) as result from iot.messages;
	</select>

</mapper>

9、创建Client.java、Server.java、PushCallback.java

Client.java

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;

public class Client {

    public static final String HOST = "tcp://127.0.0.1:61613";
    public static final String TOPIC = "IOT";
    private static final String clientid = "client";
    private MqttClient client;
    private MqttConnectOptions options;
    private String userName = "admin";
    private String passWord = "password";

    private void start() {
        try {
            // host为主机名，clientid即连接MQTT的客户端ID，一般以唯一标识符表示，MemoryPersistence设置clientid的保存形式，默认为以内存保存
            client = new MqttClient(HOST, clientid, new MemoryPersistence());
            // MQTT的连接设置
            options = new MqttConnectOptions();
            // 设置是否清空session,这里如果设置为false表示服务器会保留客户端的连接记录，这里设置为true表示每次连接到服务器都以新的身份连接
            options.setCleanSession(true);
            // 设置连接的用户名
            options.setUserName(userName);
            // 设置连接的密码
            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，但这个方法并没有重连的机制
            options.setKeepAliveInterval(20);
            // 设置回调
            client.setCallback(new PushCallback());
            MqttTopic topic = client.getTopic(TOPIC);
            //setWill方法，如果项目中需要知道客户端是否掉线可以调用该方法。设置最终端口的通知消息
            options.setWill(topic, "close".getBytes(), 2, true);

            client.connect(options);
            //订阅消息
            int[] Qos  = {1};
            String[] topic1 = {TOPIC};
            client.subscribe(topic1, Qos);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) throws MqttException {
        Client client = new Client();
        client.start();
    }
}

Server.java

import com.iot.dao.MessagesMapper;
import com.iot.pojo.Messages;
import com.iot.utils.MyBatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.eclipse.paho.client.mqttv3.*;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;

import java.awt.*;
import java.util.Scanner;

public class Server {
    
    public static final String HOST = "tcp://127.0.0.1:61613";
    public static final String TOPIC = "IOT";
    private static final String clientid = "server";
    //各参数阈值
    private static final int temperatureMax = 50;
    private static final int temperatureMin = 0;
    private static final int temperatureStaVal = 28;
    private static final int temperatureDifVal = 12;
    private static final int himidityMax = 100;
    private static final int himidityMin = 0;
    private static final int himidityStaVal = 40;
    private static final int himidityDifVal = 20;
    private static final int PM2_5Max = 700;
    private static final int PM2_5Min = 0;
    private static final int PM2_5StaVal = 300;
    private static final int PM2_5DifVal = 200;

    private static int fan;
    private static int power;
    private static int light;
    private static int temperatureCur;
    private static int himidityCur;
    private static int PM2_5Cur;

    private MqttClient client;
    private MqttTopic iot;
    private String userName = "admin";
    private String passWord = "password";
    private MqttMessage message;

    public Server() throws MqttException {
        // MemoryPersistence设置clientid的保存形式，默认为以内存保存
        client = new MqttClient(HOST, clientid, new MemoryPersistence());
        connect();
    }

    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);
            iot = client.getTopic(TOPIC);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    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());
    }

    public static int getRandom(int max, int min) {
        return (int) (Math.random() * (max - min) + min);
    }

    public static String[] getState(String project, int curVal, int staVal, int difVal) {
        String[] msg = new String[2];
        if (curVal <= staVal) {
            msg[0] = "当前" + project + "：" + curVal + "\n";
            msg[1] = "0";
        } else if (curVal <= staVal + difVal) {
            msg[0] = "当前" + project + "：" + curVal + "\n";
            msg[1] = "10";
        } else {
            msg[0] = "当前" + project + "：" + curVal + "\n";
            msg[1] = "100";
        }
        return msg;
    }

    public static String getVal() {
        temperatureCur = getRandom(temperatureMax, temperatureMin);
        himidityCur = getRandom(himidityMax, himidityMin);
        PM2_5Cur = getRandom(PM2_5Max, PM2_5Min);
        String[] msg1 = getState("temperature", temperatureCur, temperatureStaVal, temperatureDifVal);
        String[] msg2 = getState("himidity", himidityCur, himidityStaVal, himidityDifVal);
        String[] msg3 = getState("PM2_5", PM2_5Cur, PM2_5StaVal, PM2_5DifVal);

        int flag = Integer.parseInt(msg1[1]) + Integer.parseInt(msg2[1]) + Integer.parseInt(msg3[1]);
        String ele;
        if (flag < 10) {
            fan = 0;
            light = 0;
            power = 1;
            ele = "适宜工作！\n";
        } else if (flag < 100) {
            fan = 1;
            light = 1;
            power = 1;
            ele = "已经高于标准值，请注意！已开启风扇" + fan + "级，灯光" + light + "级\n";
        } else {
            fan = 2;
            if (msg3[1].equals("100")) {
                light = 2;
            } else
                light = 1;
            power = 0;
            ele = "不适工作，请速离开！已关闭机器，开启风扇" + fan + "级，灯光" + light + "级\n";
        }
        String sep = "------------消息体---------------\n";
        String sep2 = "-------------------------------";
        return sep + msg1[0] + msg2[0] + msg3[0] + ele + sep2;
    }

    public static void main(String[] args) throws MqttException, AWTException {
        Server server = new Server();
        Scanner scanner = new Scanner(System.in);
        SqlSession sqlSession= MyBatisUtils.getSqlSession();
        MessagesMapper messagesMapper=sqlSession.getMapper(MessagesMapper.class);
        int k=messagesMapper.getCount()+1;
        do {
            String msg = getVal();
            server.message = new MqttMessage();
            server.message.setQos(2);
            server.message.setRetained(true);
            server.message.setPayload(("推送" + TOPIC + "的信息\n" + msg).getBytes());
            server.publish(server.iot, server.message);
            Messages messages=new Messages(k,TOPIC,temperatureCur,himidityCur,PM2_5Cur,fan,light,power,msg);
            System.out.println(messages);

            //保存数据到数据库
            int i = messagesMapper.addMes(messages);
            if(i>0){
                System.out.println("保存成功！");
            }else{
                System.out.println("保存失败！");
            }
            sqlSession.commit();

            System.out.println(server.message.isRetained() + "------ratained状态");
            k++;
        } while (scanner.nextInt() == 0);
        sqlSession.close();
        System.out.println("已停止发送！");
    }
}

PushCallback.java

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。
 * 每个客户机标识都需要一个回调实例。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)在断开连接时调用。
 *
 *  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 {

    public void connectionLost(Throwable cause) {
        // 连接丢失后，一般在这里面进行重连
        System.out.println("连接断开，可以做重连");
    }

    public void deliveryComplete(IMqttDeliveryToken token) {
        System.out.println("deliveryComplete---------" + token.isComplete());
    }

    public void messageArrived(String topic, MqttMessage message) throws Exception {

        // subscribe后得到的消息会执行到这里面
        System.out.println("===================================================");
        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(), "UTF-8"));
        System.out.println("===================================================");
    }
}

10、点击启动测试

注意：当Server启动的时候，你可以输入0实现再次发布随机消息