首先物联网协议mqtt协议是基于tcp/ip协议的，使用了官方的mqttclient框架

/**初始化mqttclient*/private void init() { try { //MQTT的连接设置 options = new MqttConnectOptions(); //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(new Ip().host, username, new MemoryPersistence()); //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);//options.setWill(myTopic,null,2,false); //设置连接的用户名 options.setUserName(login_token); //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(60); //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----------"); } @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 { byte[] message1 = message.getPayload(); // subscribe后得到的消息会执行到这里面 System.out.println("messageArrived----------" + message1[0] + Arrays.toString(message1)); System.out.println(message1[0] == 5); String id = new String(subBytes(message1, 1, 16), "UTF-8"); System.out.print("mqtt收到的id" + id); DeviceList device = getBookById(id); System.out.print("device" + device.getName()); String name = device.getName(); String gName = device.getgName(); String type = device.getType(); System.out.print("名字为" + name + gName); /** * 使用handler发送matt接收的消息，格式为二进制数据 * */ Message msg = new Message(); msg.what = 1; if (message1[0] == 1) {// msg.obj = name + "设备心跳";// handler.sendMessage(msg); return; } if (message1[0] == 2) { msg.obj = gName + "" + name + "报警"; msg.arg1 = Integer.parseInt(type); handler.sendMessage(msg); return; } if (message1[0] == 3) { msg.obj = gName + "" + name + "上线"; handler.sendMessage(msg); return; } if (message1[0] == 4) { msg.obj = gName + "" + name + "离线"; handler.sendMessage(msg); return; } if (message1[0] == 5) { if (message1[17] == 0) { msg.obj = gName + "" + name + "关门"; } else { msg.obj = gName + "" + name + "开门"; } handler.sendMessage(msg); return; } if (message1[0] == 20 && message1[17] > 0 && message1[17] < 20) { msg.obj = name + "电池电量: " + message1[17] + "%"; handler.sendMessage(msg); System.out.println("电池:" + name + "电池电量: " + message1[17] + "%"); return; } if (message1[17] > 0) { SharedPreferences sp = getActivity().getSharedPreferences(id, getActivity().MODE_PRIVATE); // 获得sp的编辑器 SharedPreferences.Editor ed = sp.edit(); // 以键值对的显示将用户名和密码保存到sp中 ed.putString("battery", String.valueOf(message1[17])); // 提交用户名和密码 ed.commit(); } } }); } catch (Exception e) { e.printStackTrace(); } } public byte[] subBytes(byte[] src, int begin, int count) { byte[] bs = new byte[count]; System.arraycopy(src, begin, bs, 0, count); return bs; } //根据id拿到属性为id的Book对象。 public static DeviceList getBookById(String id) { DeviceList book = new DeviceList(); book.setId(id);//设置传入的id值 //books.indexOf()根据id比较对象是否相等 return deviceList1.get(deviceList1.indexOf(book)); //返回关联id的Book对象。 } private void connect() { new Thread(new Runnable() { @Override public void run() { try { client.connect(options); Message msg = new Message(); msg.what = 2; handler.sendMessage(msg); } catch (Exception e) { e.printStackTrace(); Message msg = new Message(); msg.what = 3; handler.sendMessage(msg); } } }).start(); } protected boolean onKeyDown(int keyCode, KeyEvent event) { if (client != null && keyCode == KeyEvent.KEYCODE_BACK) { try { client.disconnect(); } catch (Exception e) { e.printStackTrace(); } } return super.getActivity().onKeyDown(keyCode, event); } @Override public void onDestroy() { super.onDestroy(); try { scheduler.shutdown(); client.disconnect(); } catch (MqttException e) { e.printStackTrace(); } } private void startReconnect() { scheduler = Executors.newSingleThreadScheduledExecutor(); scheduler.scheduleAtFixedRate(new Runnable() { @Override public void run() { if (!client.isConnected()) { connect(); } } }, 0 * 1000, 10 * 1000, TimeUnit.MILLISECONDS); }其次使用handlermessage接收消息，并已notifacation的形式展示在通知栏页面 handler = new Handler() { @Override public void handleMessage(Message msg) { super.handleMessage(msg); if (msg.what == 1) { NotificationManager manager = (NotificationManager) getActivity().getSystemService(Context.NOTIFICATION_SERVICE); Notification myNotify = new Notification(); myNotify.icon = R.drawable.logo; myNotify.tickerText = "新消息"; myNotify.when = System.currentTimeMillis(); //使用默认的声音 myNotify.defaults |= Notification.DEFAULT_SOUND;//使用默认的震动 myNotify.defaults |= Notification.DEFAULT_VIBRATE;//使用默认的声音、振动、闪光 myNotify.defaults = Notification.DEFAULT_ALL;// myNotify.flags=Notification.FLAG_AUTO_CANCEL; // myNotify.flags = Notification.FLAG_NO_CLEAR;// 不能够自动清除 RemoteViews rv = new RemoteViews(getActivity().getPackageName(), R.layout.activity_notification1); rv.setTextViewText(R.id.tv_desc, (String) msg.obj); myNotify.contentView = rv; Intent intent = new Intent(getActivity(), MainActivity.class); // intent.addCategory(Intent.CATEGORY_LAUNCHER); // intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS); android.app.PendingIntent contentIntent = android.app.PendingIntent.getActivity(getActivity(), 0, intent, 0); myNotify.contentIntent = contentIntent; manager.notify(i1++, myNotify); PowerManager pm = (PowerManager) getActivity().getSystemService(Context.POWER_SERVICE); PowerManager.WakeLock wakeLock = pm.newWakeLock(PowerManager.ACQUIRE_CAUSES_WAKEUP | PowerManager.SCREEN_DIM_WAKE_LOCK, "target"); boolean screen = pm.isScreenOn(); if (!screen) {//如果灭屏 wakeLock.acquire(); wakeLock.release(); } refresh(); } else if (msg.what == 2) { System.out.println("连接成功"); System.out.print("连接成功大小" + listDatas2.size()); try { client.subscribe(myTopic, 1); client.subscribe(myTopic1, 1); } catch (MqttException e) { e.printStackTrace(); } } else if (msg.what == 3) { //Toast.makeText(MainActivity.this, "连接失败，系统正在重连", Toast.LENGTH_SHORT).show(); System.out.println("连接失败，系统正在重连"); } } };

以上这篇安卓开发之mqtt协议实例代码就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。