Java tutorial
/* * Copyright (C) 2009 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package andriod.iot.com.mqttserialtethering; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.nio.Buffer; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.UUID; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.ConcurrentLinkedQueue; import org.apache.commons.lang3.ArrayUtils; import org.eclipse.paho.client.mqttv3.MqttMessage; import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.bluetooth.BluetoothServerSocket; import android.bluetooth.BluetoothSocket; import android.content.Context; import android.os.SystemClock; import android.util.Log; import android.widget.Toast; /** * This class does all the work for setting up and managing Bluetooth * connections with other devices. It has a thread that listens for incoming * connections, a thread for connecting with a device, and a thread for * performing data transmissions when connected. */ public class BluetoothService { // Debugging private static final String TAG = "RobotBluetoothService"; private static final boolean D = true; private static boolean SEND_DATA = false; public static ConcurrentHashMap<String, MqttMessage> arrivedMessage = new ConcurrentHashMap<String, MqttMessage>(); private List<String> subscribedQueues = new ArrayList<String>(); MQTTService mqttSerivce; // Name for the SDP record when creating server socket private static final String NAME_INSECURE = "BluetoothChatInsecure"; // Unique UUID for this application private static final UUID MY_UUID_INSECURE = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"); // Member fields private final BluetoothAdapter mAdapter; private AcceptThread mInsecureAcceptThread; private ConnectThread mConnectThread; private ConnectedThread mConnectedThread; private int mState; // Constants that indicate the current connection state public static final int STATE_NONE = 0; // we're doing nothing public static final int STATE_LISTEN = 1; // now listening for incoming // connections public static final int STATE_CONNECTING = 2; // now initiating an outgoing // connection public static final int STATE_CONNECTED = 3; // now connected to a remote // device /** * Constructor. Prepares a new BluetoothChat session. * * @param context * The UI Activity Context * @param handler * A Handler to send messages back to the UI Activity */ Context thisContext; HashMap<String, Byte> mHandler; public BluetoothService(Context context, HashMap<String, Byte> handler) { mAdapter = BluetoothAdapter.getDefaultAdapter(); mState = STATE_NONE; thisContext = context; mHandler = handler; } /** * Set the current state of the chat connection * * @param state * An integer defining the current connection state */ private synchronized void setState(int state) { if (D) Log.d(TAG, "setState() " + mState + " -> " + state); mState = state; // Give the new state to the Handler so the UI Activity can update // mHandler.obtainMessage(BluetoothChat.MESSAGE_STATE_CHANGE, state, // -1).sendToTarget(); } /** * Return the current connection state. */ public synchronized int getState() { return mState; } /** * Start the chat service. Specifically start AcceptThread to begin a * session in listening (server) mode. Called by the Activity onResume() */ public synchronized void start() { if (D) Log.d(TAG, "start"); // Cancel any thread attempting to make a connection if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } // Cancel any thread currently running a connection if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } setState(STATE_LISTEN); if (mInsecureAcceptThread == null) { mInsecureAcceptThread = new AcceptThread(false); mInsecureAcceptThread.start(); } } /** * Start the ConnectThread to initiate a connection to a remote device. * * @param device * The BluetoothDevice to connect * @param secure * Socket Security type - Secure (true) , Insecure (false) */ public synchronized void connect(BluetoothDevice device, boolean secure) { if (D) Log.d(TAG, "connect to: " + device); // Cancel any thread attempting to make a connection if (mState == STATE_CONNECTING) { if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } } // Cancel any thread currently running a connection if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } // Start the thread to connect with the given device mConnectThread = new ConnectThread(device, secure); mConnectThread.start(); setState(STATE_CONNECTING); } /** * Start the ConnectedThread to begin managing a Bluetooth connection * * @param socket * The BluetoothSocket on which the connection was made * @param device * The BluetoothDevice that has been connected */ public synchronized void connected(BluetoothSocket socket, BluetoothDevice device, final String socketType) { if (D) Log.d(TAG, "connected, Socket Type:" + socketType); // Cancel the thread that completed the connection if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } // Cancel any thread currently running a connection if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } // Cancel the accept thread because we only want to connect to one // device if (mInsecureAcceptThread != null) { mInsecureAcceptThread.cancel(); mInsecureAcceptThread = null; } // Start the thread to manage the connection and perform transmissions mConnectedThread = new ConnectedThread(socket, socketType); mConnectedThread.start(); // Send the name of the connected device back to the UI Activity // Message msg = // mHandler.obtainMessage(BluetoothChat.MESSAGE_DEVICE_NAME); // Bundle bundle = new Bundle(); // bundle.putString(BluetoothChat.DEVICE_NAME, device.getName()); // msg.setData(bundle); // mHandler.sendMessage(msg); setState(STATE_CONNECTED); } /** * Stop all threads */ public synchronized void stop() { if (D) Log.d(TAG, "stop"); if (mConnectThread != null) { mConnectThread.cancel(); mConnectThread = null; } if (mConnectedThread != null) { mConnectedThread.cancel(); mConnectedThread = null; } if (mInsecureAcceptThread != null) { mInsecureAcceptThread.cancel(); mInsecureAcceptThread = null; } setState(STATE_NONE); } /** * Write to the ConnectedThread in an unsynchronized manner * * @param out * The bytes to write * @see andriod.iot.com.mqttserialtethering.BluetoothService.ConnectedThread#write(byte[]) */ public synchronized void write(byte[] out) { // Create temporary object ConnectedThread r; // Synchronize a copy of the ConnectedThread synchronized (this) { if (mState != STATE_CONNECTED) return; r = mConnectedThread; } // Perform the write unsynchronized r.write(out); } /** * Indicate that the connection attempt failed and notify the UI Activity. */ private void connectionFailed() { // Send a failure message back to the Activity // Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_TOAST); // Bundle bundle = new Bundle(); // bundle.putString(BluetoothChat.TOAST, "Unable to connect device"); // msg.setData(bundle); // mHandler.sendMessage(msg); // Start the service over to restart listening mode BluetoothService.this.start(); } /** * Indicate that the connection was lost and notify the UI Activity. */ private void connectionLost() { // Send a failure message back to the Activity // Message msg = mHandler.obtainMessage(BluetoothChat.MESSAGE_TOAST); // Bundle bundle = new Bundle(); // bundle.putString(BluetoothChat.TOAST, "Device connection was lost"); // msg.setData(bundle); // mHandler.sendMessage(msg); // Start the service over to restart listening mode BluetoothService.this.start(); } /** * This thread runs while listening for incoming connections. It behaves * like a server-side client. It runs until a connection is accepted (or * until cancelled). */ private class AcceptThread extends Thread { // The local server socket private final BluetoothServerSocket mmServerSocket; private String mSocketType; public AcceptThread(boolean secure) { BluetoothServerSocket tmp = null; mSocketType = secure ? "Secure" : "Insecure"; // Create a new listening server socket try { tmp = mAdapter.listenUsingInsecureRfcommWithServiceRecord(NAME_INSECURE, MY_UUID_INSECURE); } catch (IOException e) { Log.e(TAG, "Socket Type: " + mSocketType + "listen() failed", e); } mmServerSocket = tmp; } public void run() { if (D) Log.d(TAG, "Socket Type: " + mSocketType + "BEGIN mAcceptThread" + this); setName("AcceptThread" + mSocketType); BluetoothSocket socket = null; // Listen to the server socket if we're not connected while (mState != STATE_CONNECTED) { try { // This is a blocking call and will only return on a // successful connection or an exception socket = mmServerSocket.accept(); } catch (IOException e) { Log.e(TAG, "Socket Type: " + mSocketType + "accept() failed", e); break; } // If a connection was accepted if (socket != null) { synchronized (BluetoothService.this) { switch (mState) { case STATE_LISTEN: case STATE_CONNECTING: // Situation normal. Start the connected thread. connected(socket, socket.getRemoteDevice(), mSocketType); break; case STATE_NONE: case STATE_CONNECTED: // Either not ready or already connected. Terminate // new socket. try { socket.close(); } catch (IOException e) { Log.e(TAG, "Could not close unwanted socket", e); } break; } } } } if (D) Log.i(TAG, "END mAcceptThread, socket Type: " + mSocketType); } public void cancel() { if (D) Log.d(TAG, "Socket Type" + mSocketType + "cancel " + this); try { mmServerSocket.close(); } catch (IOException e) { Log.e(TAG, "Socket Type" + mSocketType + "close() of server failed", e); } } } /** * This thread runs while attempting to make an outgoing connection with a * device. It runs straight through; the connection either succeeds or * fails. */ private class ConnectThread extends Thread { private final BluetoothSocket mmSocket; private final BluetoothDevice mmDevice; private String mSocketType; public ConnectThread(BluetoothDevice device, boolean secure) { mmDevice = device; BluetoothSocket tmp = null; mSocketType = secure ? "Secure" : "Insecure"; // Get a BluetoothSocket for a connection with the // given BluetoothDevice try { tmp = device.createInsecureRfcommSocketToServiceRecord(MY_UUID_INSECURE); } catch (IOException e) { Log.e(TAG, "Socket Type: " + mSocketType + "create() failed", e); } mmSocket = tmp; } public void run() { Log.i(TAG, "BEGIN mConnectThread SocketType:" + mSocketType); setName("ConnectThread" + mSocketType); // Always cancel discovery because it will slow down a connection mAdapter.cancelDiscovery(); // Make a connection to the BluetoothSocket try { // This is a blocking call and will only return on a // successful connection or an exception mmSocket.connect(); } catch (IOException e) { // Close the socket try { mmSocket.close(); } catch (IOException e2) { Log.e(TAG, "unable to close() " + mSocketType + " socket during connection failure", e2); } connectionFailed(); return; } // Reset the ConnectThread because we're done synchronized (BluetoothService.this) { mConnectThread = null; } // Start the connected thread connected(mmSocket, mmDevice, mSocketType); } public void cancel() { try { mmSocket.close(); } catch (IOException e) { Log.e(TAG, "close() of connect " + mSocketType + " socket failed", e); } } } /** * This thread runs during a connection with a remote device. It handles all * incoming and outgoing transmissions. */ private class ConnectedThread extends Thread { private final BluetoothSocket mmSocket; private final InputStream mmInStream; private final OutputStream mmOutStream; public ConnectedThread(BluetoothSocket socket, String socketType) { Log.d(TAG, "create ConnectedThread: " + socketType); mmSocket = socket; InputStream tmpIn = null; OutputStream tmpOut = null; // Get the BluetoothSocket input and output streams try { tmpIn = socket.getInputStream(); tmpOut = socket.getOutputStream(); } catch (IOException e) { Log.e(TAG, "temp sockets not created", e); } mmInStream = tmpIn; mmOutStream = tmpOut; } private String readBuffer(InputStream mmInStream, int data) throws IOException { List<Byte> byteArray = new ArrayList<Byte>(); while (true) { data = mmInStream.read(); if (data == 245) { break; } byteArray.add((byte) data); } Byte[] buffer = new Byte[byteArray.size()]; byteArray.toArray(buffer); byte[] pBuffer = ArrayUtils.toPrimitive(buffer); return new String(pBuffer); } public void run() { Log.i(TAG, "BEGIN mConnectedThread"); String clientId = null; String hostname = null; String portnumber = null; String publishQueue = null; String publishPayload = null; String subscribeQueue = null; String username = null; String password = null; // Keep listening to the InputStream while connected while (true) { try { // Read from the InputStream // using a fixed width if (mmInStream.available() > 0) { int data = mmInStream.read(); if (data == 1) { clientId = readBuffer(mmInStream, data); mqttSerivce = new MQTTService(clientId); } else if (data == 2) { hostname = readBuffer(mmInStream, data); } else if (data == 3) { portnumber = readBuffer(mmInStream, data); } else if (data == 4) { username = readBuffer(mmInStream, data); } else if (data == 5) { password = readBuffer(mmInStream, data); mqttSerivce.begin(hostname, Integer.valueOf(portnumber), username, password); } else if (data == 6) { mqttSerivce.connect(); } else if (data == 7) { mqttSerivce.disconnect(); } else if (data == 8) { publishQueue = readBuffer(mmInStream, data); } else if (data == 9) { publishPayload = readBuffer(mmInStream, data); if (mqttSerivce != null) { mqttSerivce.publish(publishQueue, publishPayload); } } else if (data == 10) { subscribeQueue = readBuffer(mmInStream, data); subscribedQueues.add(subscribeQueue); mqttSerivce.subscribe(subscribeQueue, new ArduinoCallback()); } } else { SystemClock.sleep(100); if (mqttSerivce != null) { if (!mqttSerivce.isConnected()) { SystemClock.sleep(200); mqttSerivce.connect(); } } } if (arrivedMessage.size() > 0) { for (String key : arrivedMessage.keySet()) { String json = "{\"topic\":\"" + key + "\",\"payload\":\"" + arrivedMessage.get(key) + "\"}"; write(json.getBytes()); } write(new byte[] { (byte) 254 }); arrivedMessage.clear(); } // Send the obtained bytes to the UI Activity // mHandler.obtainMessage(BluetoothChat.MESSAGE_READ, bytes, // -1, buffer) .sendToTarget(); } catch (IOException e) { Log.e(TAG, "disconnected", e); connectionLost(); // Start the service over to restart listening mode BluetoothService.this.start(); break; } catch (Exception exception) { } } } /** * Write to the connected OutStream. * * @param buffer * The bytes to write */ public void write(byte[] buffer) { try { mmOutStream.write(buffer); } catch (IOException e) { Log.e(TAG, "Exception during write", e); } } public void cancel() { try { mmSocket.close(); } catch (IOException e) { Log.e(TAG, "close() of connect socket failed", e); } } } }