很小白的基于 MQTT 通讯的 Java 工程
package com.example.mqtt_project;
import androidx.appcompat.app.AppCompatActivity;
import android.annotation.SuppressLint;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import org.eclipse.paho.client.mqttv3.IMqttDeliveryToken;
import org.eclipse.paho.client.mqttv3.MqttCallback;
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.MqttMessage;
import org.eclipse.paho.client.mqttv3.persist.MemoryPersistence;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
//
//这里是我的安卓测试，测试一下输入设置好了没有yes or no
//
public class MainActivity extends AppCompatActivity {
// private String host = "tcp://106.13.150.28:1883";
private String host = "tcp://116.62.28.158:1883";
// private String userName = "android";
// private String passWord = "android";
private String userName = "winshine";
private String passWord = "winshine123";
private String mqtt_id = "523266538";
private String mqtt_sub_topic = "523266538_PC"; //为了保证你不受到别人的消息
private String mqtt_pub_topic = "523266538"; //为了保证你不受到别人的消息
// private String mqtt_sub_topic = "hello"; //为了保证你不受到别人的消息
// private String mqtt_pub_topic = "523266538"; //为了保证你不受到别人的消息
private Button btn_1;
private Button btn_open;
private Button btn_close;
private ImageView image_open;
private ImageView image_door;
private ImageView image_wide;
private ImageView image_lei;
private ImageView image_pm;
private ImageView image_th;
private TextView text_old;
private MqttClient client;
private MqttConnectOptions options;
private Handler handler;
private ScheduledExecutorService scheduler;
private int led_flag = 1;
private String open_led ="LEDON";
private String close_led ="LEDOFF";
private int mqtt_flag = 0;
@SuppressLint("HandlerLeak")
@Override
protected void onCreate(Bundle savedInstanceState) {
//界面打开后，最先运行的地方
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);//对应界面UI
//用来界面初始化，控件初始化，某种意义上类似main()函数
ui_init();//初始化
btn_1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//这里既是单击之后的操作
//("这是一个单击操作"); java 中的打印操作
/*
更直观的方式用弹窗 ： toast
context：界面选择 这里为 : 当前界面
text： 显示的text
Toast.LENGTH_LONG 显示时长，这里选择 LENGTH_LONG
context 和 text 都不需要自己敲的
*/
Toast.makeText(MainActivity.this,"这是一个单击操作",Toast.LENGTH_LONG).show();
text_old.setText("我是新的内容");
}
});
/*
学会按钮单击事件，图片也可以单击事件
单击第一个图片，通过mqtt发布一个消息
*/
image_open.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
try
{
if(led_flag == 0) {
publishmessageplus(mqtt_pub_topic, open_led);
led_flag =1;
Toast.makeText(MainActivity.this,"开灯",Toast.LENGTH_SHORT).show();
}
else
{
publishmessageplus(mqtt_pub_topic, close_led);
led_flag =0;
Toast.makeText(MainActivity.this,"关灯",Toast.LENGTH_SHORT).show();
}
}
catch (Exception e)
{
e.toString();
}
}
});
image_door.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this,"我是开门按钮",Toast.LENGTH_LONG).show();
}
});
image_lei.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this,"这里做蓝牙",Toast.LENGTH_LONG).show();
Intent intent = new Intent(MainActivity.this,
BlueTestActivity1.class);
startActivity(intent);
}
});
btn_open.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this,"打开mqtt重连",Toast.LENGTH_LONG).show();
mqtt_flag = 0;//打开重连
}
});
btn_close.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this,"关闭mqtt重连",Toast.LENGTH_LONG).show();
mqtt_flag = 1;//打开重连
}
});
//两个控件联动，按钮单击改变textview的值
//#########################################################//
Mqtt_init();
startReconnect();
handler = new Handler() {
@SuppressLint("SetTextI18n")
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what){
case 1: //开机校验更新回传
break;
case 2: // 反馈回传
break;
case 3: //MQTT 收到消息回传 UTF8Buffer msg=new UTF8Buffer(());
String temp=null;
try {
temp=msg.obj.toString();
if(temp!=null&&temp.contains("temp"))
{
String T_val = msg.obj.toString().substring(msg.obj.toString().indexOf("temp:")+5,msg.obj.toString().indexOf("h"));
String H_val = msg.obj.toString().substring(msg.obj.toString().indexOf("temp:")+16);
Toast.makeText(MainActivity.this,msg.obj.toString(),Toast.LENGTH_LONG).show();
String text_val="温度:"+T_val+""+"湿度:"+H_val;
text_old.setText(text_val);
}
}
catch (Exception e)
{
e.toString();
}
break;
case 30: //连接失败
Toast.makeText(MainActivity.this,"连接失败",Toast.LENGTH_LONG).show();
break;
case 31: //连接成功
Toast.makeText(MainActivity.this,"连接成功",Toast.LENGTH_LONG).show();
try {
client.subscribe(mqtt_sub_topic,1);
} catch (MqttException e) {
e.printStackTrace();
}
break;
default:
break;
}
}
};
}
//初始化，绑定对应的控件ID
private void ui_init() {
btn_1 = findViewById(R.id.btn_1);
image_open = findViewById(R.id.image_open);
image_door = findViewById(R.id.image_door);
image_lei = findViewById(R.id.image_lei);
image_th = findViewById(R.id.image_th);
image_wide = findViewById(R.id.image_wide);
image_pm = findViewById(R.id.image_pm);
text_old = findViewById(R.id.text_old);
btn_open = findViewById(R.id.btn_open);
btn_close = findViewById(R.id.btn_close);
}
private void Mqtt_init() {
try {
//host为主机名，test为clientid即连接MQTT的客户端ID，一般以客户端唯一标识符表示，MemoryPersistence设置clientid的保存形式，默认为以内存保存
client = new MqttClient(host, mqtt_id,
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(false);
//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 MqttCallback() {
@Override
public void connectionLost(Throwable cause) {
//连接丢失后，一般在这里面进行重连
System.out.println("connectionLost----------");
//startReconnect();
}
@Override
public void deliveryComplete(IMqttDeliveryToken token) {
//publish后会执行到这里
System.out.println("deliveryComplete---------"
+ token.isComplete());
}
@Override
public void messageArrived(String topicName, MqttMessage message)
throws Exception {
//subscribe后得到的消息会执行到这里面
System.out.println("messageArrived----------");
//封装message包
Message msg = new Message();
msg.what = 3; //收到消息标志位
msg.obj = topicName + "---" + message.toString();
//发送message 到 handler
handler.sendMessage(msg); // hander 回传
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
private void Mqtt_connect() {
new Thread(new Runnable() {
@Override
public void run() {
try {
if(!(client.isConnected()) ) //如果还未连接
{
if(mqtt_flag == 0) { //只有当flag == 0时才能一直重新连接
client.connect(options);
Message msg = new Message();
msg.what = 31;
handler.sendMessage(msg);
}
}
} catch (Exception e) {
e.printStackTrace();
Message msg = new Message();
msg.what = 30;
handler.sendMessage(msg);
}
}
}).start();
}
private void startReconnect() {
scheduler = Executors.newSingleThreadScheduledExecutor();
scheduler.scheduleAtFixedRate(new Runnable() {
@Override
public void run() {
if (!client.isConnected()) {
Mqtt_connect();
}
}
}, 0 * 1000, 10 * 1000, TimeUnit.MILLISECONDS);
}
private void publishmessageplus(String topic,String message2) {
if (client == null || !client.isConnected()) {
return;
}
MqttMessage message = new MqttMessage();
message.setQos(0);
message.setPayload(message2.getBytes());
try {
client.publish(topic,message);
} catch (MqttException e) {
e.printStackTrace();
}
}
}