undot.safedrivers.BLE.BluetoothLeService.java Source code

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Here is the source code for undot.safedrivers.BLE.BluetoothLeService.java

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/*
 * Copyright (C) 2013 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 undot.safedrivers.BLE;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.NotificationManager;
import android.app.Service;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothGatt;
import android.bluetooth.BluetoothGattCallback;
import android.bluetooth.BluetoothGattCharacteristic;
import android.bluetooth.BluetoothGattDescriptor;
import android.bluetooth.BluetoothGattService;
import android.bluetooth.BluetoothManager;
import android.bluetooth.BluetoothProfile;
import android.content.Context;
import android.content.Intent;
import android.os.Binder;
import android.os.Handler;
import android.os.IBinder;
import android.os.Vibrator;
import android.support.v4.app.NotificationCompat;
import android.util.Log;
import android.widget.Toast;

import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.List;

import undot.safedrivers.R;

/**
 * Service for managing connection and data communication with a GATT server hosted on a
 * given Bluetooth LE device.
 */
public class BluetoothLeService extends Service {
    private final static String TAG = BluetoothLeService.class.getSimpleName();

    private static BluetoothGattCharacteristic mSCharacteristic, mModelNumberCharacteristic,
            mSerialPortCharacteristic, mCommandCharacteristic;
    BluetoothLeService mBluetoothLeService;
    private ArrayList<ArrayList<BluetoothGattCharacteristic>> mGattCharacteristics = new ArrayList<ArrayList<BluetoothGattCharacteristic>>();
    private boolean mScanning = false;
    AlertDialog mScanDeviceDialog;
    private String mDeviceName;
    private String mDeviceAddress;

    public enum connectionStateEnum {
        isNull, isScanning, isToScan, isConnecting, isConnected, isDisconnecting
    };

    private static final int REQUEST_ENABLE_BT = 1;

    private Handler mHandler = new Handler();

    public boolean mConnected = false;
    private int mBaudrate = 115200; //set the default baud rate to 115200
    private String mPassword = "AT+PASSWOR=DFRobot\r\n";

    private String mBaudrateBuffer = "AT+CURRUART=" + mBaudrate + "\r\n";

    boolean notified = false;
    public static final String SerialPortUUID = "0000dfb1-0000-1000-8000-00805f9b34fb";
    public static final String CommandUUID = "0000dfb2-0000-1000-8000-00805f9b34fb";
    public static final String ModelNumberStringUUID = "00002a24-0000-1000-8000-00805f9b34fb";

    int rssi_value = 0;
    int sensor_value_sum = 0;
    int sensor_counter = 0;
    int sensor_value = 0;
    int rssicounter = 0;

    private BluetoothManager mBluetoothManager;
    private BluetoothAdapter mBluetoothAdapter;
    public static BluetoothGatt mBluetoothGatt;
    public String mBluetoothDeviceAddress;

    private static final int STATE_DISCONNECTED = 0;
    private static final int STATE_CONNECTING = 1;
    private static final int STATE_CONNECTED = 2;
    public int mConnectionState = STATE_DISCONNECTED;

    //To tell the onCharacteristicWrite call back function that this is a new characteristic, 
    //not the Write Characteristic to the device successfully.
    private static final int WRITE_NEW_CHARACTERISTIC = -1;
    //define the limited length of the characteristic.
    private static final int MAX_CHARACTERISTIC_LENGTH = 17;
    //Show that Characteristic is writing or not.
    private boolean mIsWritingCharacteristic = false;

    //class to store the Characteristic and content string push into the ring buffer.
    private class BluetoothGattCharacteristicHelper {
        BluetoothGattCharacteristic mCharacteristic;
        String mCharacteristicValue;

        BluetoothGattCharacteristicHelper(BluetoothGattCharacteristic characteristic, String characteristicValue) {
            mCharacteristic = characteristic;
            mCharacteristicValue = characteristicValue;
        }
    }

    //ring buffer
    private RingBuffer<BluetoothGattCharacteristicHelper> mCharacteristicRingBuffer = new RingBuffer<BluetoothGattCharacteristicHelper>(
            8);

    public final static String ACTION_GATT_CONNECTED = "com.example.bluetooth.le.ACTION_GATT_CONNECTED";
    public final static String ACTION_GATT_DISCONNECTED = "com.example.bluetooth.le.ACTION_GATT_DISCONNECTED";
    public final static String ACTION_GATT_SERVICES_DISCOVERED = "com.example.bluetooth.le.ACTION_GATT_SERVICES_DISCOVERED";
    public final static String ACTION_DATA_AVAILABLE = "com.example.bluetooth.le.ACTION_DATA_AVAILABLE";
    public final static String EXTRA_DATA = "com.example.bluetooth.le.EXTRA_DATA";
    //    public final static UUID UUID_HEART_RATE_MEASUREMENT =
    //            UUID.fromString(SampleGattAttributes.HEART_RATE_MEASUREMENT);

    @Override
    public void onCreate() {
        super.onCreate();
        initialize();

    }

    // Implements callback methods for GATT events that the app cares about.  For example,
    // connection change and services discovered.
    private final BluetoothGattCallback mGattCallback = new BluetoothGattCallback() {
        @Override
        public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
            String intentAction;
            System.out.println("BluetoothGattCallback----onConnectionStateChange" + newState);
            if (newState == BluetoothProfile.STATE_CONNECTED) {
                intentAction = ACTION_GATT_CONNECTED;
                mConnectionState = STATE_CONNECTED;
                broadcastUpdate(intentAction);
                Log.i(TAG, "Connected to GATT server.");
                mBluetoothAdapter.stopLeScan(mLeScanCallback);
                // Attempts to discover services after successful connection.
                if (mBluetoothGatt.discoverServices()) {
                    Log.i(TAG, "Attempting to start service discovery:");

                } else {
                    Log.i(TAG, "Attempting to start service discovery:not success");

                }

            } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
                intentAction = ACTION_GATT_DISCONNECTED;
                mConnectionState = STATE_DISCONNECTED;
                Log.i(TAG, "Disconnected from GATT server.");
                broadcastUpdate(intentAction);
            }
        }

        @Override
        public void onReadRemoteRssi(BluetoothGatt gatt, int rssi, int status) {
            super.onReadRemoteRssi(gatt, rssi, status);
            Log.d("rssionremote", rssi + "");
            if (rssi < -90) {
                //  rssi_value = rssi;
                rssicounter++;
            }
            //broadcastUpdate(rssi);
        }

        @Override
        public void onServicesDiscovered(BluetoothGatt gatt, int status) {
            System.out.println("onServicesDiscovered " + status);
            if (status == BluetoothGatt.GATT_SUCCESS) {
                broadcastUpdate(ACTION_GATT_SERVICES_DISCOVERED);
                for (BluetoothGattService gattService : getSupportedGattServices()) {
                    System.out.println("ACTION_GATT_SERVICES_DISCOVERED  " + gattService.getUuid().toString());
                }
                getGattServices(getSupportedGattServices());
            } else {
                Log.w(TAG, "onServicesDiscovered received: " + status);
            }
        }

        @Override
        public void onCharacteristicWrite(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic,
                int status) {
            //this block should be synchronized to prevent the function overloading
            synchronized (this) {
                //CharacteristicWrite success
                if (status == BluetoothGatt.GATT_SUCCESS) {
                    System.out.println("onCharacteristicWrite success:" + new String(characteristic.getValue()));
                    if (mCharacteristicRingBuffer.isEmpty()) {
                        mIsWritingCharacteristic = false;
                    } else {
                        BluetoothGattCharacteristicHelper bluetoothGattCharacteristicHelper = mCharacteristicRingBuffer
                                .next();
                        if (bluetoothGattCharacteristicHelper.mCharacteristicValue
                                .length() > MAX_CHARACTERISTIC_LENGTH) {
                            try {
                                bluetoothGattCharacteristicHelper.mCharacteristic
                                        .setValue(bluetoothGattCharacteristicHelper.mCharacteristicValue
                                                .substring(0, MAX_CHARACTERISTIC_LENGTH).getBytes("ISO-8859-1"));

                            } catch (UnsupportedEncodingException e) {
                                // this should never happen because "US-ASCII" is hard-coded.
                                throw new IllegalStateException(e);
                            }

                            if (mBluetoothGatt
                                    .writeCharacteristic(bluetoothGattCharacteristicHelper.mCharacteristic)) {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":success");
                            } else {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":failure");
                            }
                            bluetoothGattCharacteristicHelper.mCharacteristicValue = bluetoothGattCharacteristicHelper.mCharacteristicValue
                                    .substring(MAX_CHARACTERISTIC_LENGTH);
                        } else {
                            try {
                                bluetoothGattCharacteristicHelper.mCharacteristic
                                        .setValue(bluetoothGattCharacteristicHelper.mCharacteristicValue
                                                .getBytes("ISO-8859-1"));
                            } catch (UnsupportedEncodingException e) {
                                // this should never happen because "US-ASCII" is hard-coded.
                                throw new IllegalStateException(e);
                            }

                            if (mBluetoothGatt
                                    .writeCharacteristic(bluetoothGattCharacteristicHelper.mCharacteristic)) {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":success");
                            } else {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":failure");
                            }
                            bluetoothGattCharacteristicHelper.mCharacteristicValue = "";

                            //                        System.out.print("before pop:");
                            //                        System.out.println(mCharacteristicRingBuffer.size());
                            mCharacteristicRingBuffer.pop();
                            //                        System.out.print("after pop:");
                            //                        System.out.println(mCharacteristicRingBuffer.size());
                        }
                    }
                }
                //WRITE a NEW CHARACTERISTIC
                else if (status == WRITE_NEW_CHARACTERISTIC) {
                    if ((!mCharacteristicRingBuffer.isEmpty()) && mIsWritingCharacteristic == false) {
                        BluetoothGattCharacteristicHelper bluetoothGattCharacteristicHelper = mCharacteristicRingBuffer
                                .next();
                        if (bluetoothGattCharacteristicHelper.mCharacteristicValue
                                .length() > MAX_CHARACTERISTIC_LENGTH) {

                            try {
                                bluetoothGattCharacteristicHelper.mCharacteristic
                                        .setValue(bluetoothGattCharacteristicHelper.mCharacteristicValue
                                                .substring(0, MAX_CHARACTERISTIC_LENGTH).getBytes("ISO-8859-1"));
                            } catch (UnsupportedEncodingException e) {
                                // this should never happen because "US-ASCII" is hard-coded.
                                throw new IllegalStateException(e);
                            }

                            if (mBluetoothGatt
                                    .writeCharacteristic(bluetoothGattCharacteristicHelper.mCharacteristic)) {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":success");
                            } else {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":failure");
                            }
                            bluetoothGattCharacteristicHelper.mCharacteristicValue = bluetoothGattCharacteristicHelper.mCharacteristicValue
                                    .substring(MAX_CHARACTERISTIC_LENGTH);
                        } else {
                            try {
                                bluetoothGattCharacteristicHelper.mCharacteristic
                                        .setValue(bluetoothGattCharacteristicHelper.mCharacteristicValue
                                                .getBytes("ISO-8859-1"));
                            } catch (UnsupportedEncodingException e) {
                                // this should never happen because "US-ASCII" is hard-coded.
                                throw new IllegalStateException(e);
                            }

                            if (mBluetoothGatt
                                    .writeCharacteristic(bluetoothGattCharacteristicHelper.mCharacteristic)) {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":success");
                                //                             System.out.println((byte)bluetoothGattCharacteristicHelper.mCharacteristic.getValue()[0]);
                                //                             System.out.println((byte)bluetoothGattCharacteristicHelper.mCharacteristic.getValue()[1]);
                                //                             System.out.println((byte)bluetoothGattCharacteristicHelper.mCharacteristic.getValue()[2]);
                                //                             System.out.println((byte)bluetoothGattCharacteristicHelper.mCharacteristic.getValue()[3]);
                                //                             System.out.println((byte)bluetoothGattCharacteristicHelper.mCharacteristic.getValue()[4]);
                                //                             System.out.println((byte)bluetoothGattCharacteristicHelper.mCharacteristic.getValue()[5]);

                            } else {
                                System.out.println("writeCharacteristic init "
                                        + new String(bluetoothGattCharacteristicHelper.mCharacteristic.getValue())
                                        + ":failure");
                            }
                            bluetoothGattCharacteristicHelper.mCharacteristicValue = "";

                            //                           System.out.print("before pop:");
                            //                           System.out.println(mCharacteristicRingBuffer.size());
                            mCharacteristicRingBuffer.pop();
                            //                           System.out.print("after pop:");
                            //                           System.out.println(mCharacteristicRingBuffer.size());
                        }
                    }

                    mIsWritingCharacteristic = true;

                    //clear the buffer to prevent the lock of the mIsWritingCharacteristic
                    if (mCharacteristicRingBuffer.isFull()) {
                        mCharacteristicRingBuffer.clear();
                        mIsWritingCharacteristic = false;
                    }
                } else
                //CharacteristicWrite fail
                {
                    mCharacteristicRingBuffer.clear();
                    System.out.println("onCharacteristicWrite fail:" + new String(characteristic.getValue()));
                    System.out.println(status);
                }
            }
        }

        @Override
        public void onCharacteristicRead(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic,
                int status) {
            if (status == BluetoothGatt.GATT_SUCCESS) {
                gatt.readRemoteRssi();
                System.out.println("onCharacteristicRead  " + characteristic.getUuid().toString());
                if (mSCharacteristic == mModelNumberCharacteristic) {
                    if (new String(characteristic.getValue()).toUpperCase().startsWith("DF BLUNO")) {
                        setCharacteristicNotification(mSCharacteristic, false);
                        mSCharacteristic = mCommandCharacteristic;
                        mSCharacteristic.setValue(mPassword);
                        writeCharacteristic(mSCharacteristic);
                        mSCharacteristic.setValue(mBaudrateBuffer);
                        writeCharacteristic(mSCharacteristic);
                        mSCharacteristic = mSerialPortCharacteristic;
                        setCharacteristicNotification(mSCharacteristic, true);
                        mConnectionState = STATE_CONNECTED;

                    } else {
                        Toast.makeText(getBaseContext(), "Please select DFRobot devices", Toast.LENGTH_SHORT)
                                .show();
                    }
                } else if (mSCharacteristic == mSerialPortCharacteristic) {
                    //    Log.d("data",new String(characteristic.getValue()));
                }
                broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
            }
        }

        @Override
        public void onDescriptorWrite(BluetoothGatt gatt, BluetoothGattDescriptor characteristic, int status) {
            System.out.println("onDescriptorWrite  " + characteristic.getUuid().toString() + " " + status);
        }

        @Override
        public void onCharacteristicChanged(BluetoothGatt gatt, BluetoothGattCharacteristic characteristic) {
            //System.out.println("onCharacteristicChanged  "+new String(characteristic.getValue()));
            //0 Log.d("data", new String(characteristic.getValue()));
            gatt.readRemoteRssi();
            // TODO Auto-generated method stub
            String[] values = new String[1];
            values[0] = new String(characteristic.getValue()).substring(0, 1);

            //  Log.d("sitting",Integer.decode(values[0].replaceAll("[^\\.0123456789]", "").substring(0,1))+"");

            if (Integer.decode(values[0].replaceAll("[^\\.0123456789]", "")) == 1
                    || Integer.decode(values[0].replaceAll("[^\\.0123456789]", "")) == 0) {
                // Log.d("is","numeric");
                sensor_value_sum += Integer.decode(values[0].replaceAll("[^\\.0123456789]", ""));
                sensor_counter++;
                if (sensor_counter == 10) {
                    sensor_value = (sensor_value_sum / sensor_counter);
                    Log.d("sensor value", sensor_value_sum + " " + sensor_counter);
                    sensor_counter = 0;
                    sensor_value_sum = 0;

                }
            }
            Log.d("rssicounter", rssicounter + "");

            if (rssicounter > 10 && sensor_value == 1) {
                Vibrator v = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
                // Vibrate for 500 milliseconds
                v.vibrate(500);
                if (!notified) {
                    NotificationCompat.Builder mBuilder = new NotificationCompat.Builder(getBaseContext())
                            .setSmallIcon(R.mipmap.ic_launcher).setContentTitle(" ?")
                            .setContentText("  ?!");
                    // Sets an ID for the notification
                    int mNotificationId = 001;
                    // Gets an instance of the NotificationManager service
                    NotificationManager mNotifyMgr = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
                    // Builds the notification and issues it.
                    mNotifyMgr.notify(mNotificationId, mBuilder.build());
                    notified = true;
                }
                rssicounter = 0;
            } else if (rssicounter > 10) {
                rssicounter = 0;
            }
            // broadcastUpdate(ACTION_DATA_AVAILABLE, characteristic);
        }
    };

    public static boolean isNumeric(String str) {
        try {
            double d = Double.parseDouble(str);
        } catch (NumberFormatException nfe) {
            return false;
        }
        return true;
    }

    private void broadcastUpdate(final String action) {
        final Intent intent = new Intent(action);
        sendBroadcast(intent);
    }

    private void broadcastUpdate(final String action, final BluetoothGattCharacteristic characteristic) {
        final Intent intent = new Intent(action);
        System.out.println("BluetoothLeService broadcastUpdate");
        // This is special handling for the Heart Rate Measurement profile.  Data parsing is
        // carried out as per profile specifications:
        // http://developer.bluetooth.org/gatt/characteristics/Pages/CharacteristicViewer.aspx?u=org.bluetooth.characteristic.heart_rate_measurement.xml
        //        if (UUID_HEART_RATE_MEASUREMENT.equals(characteristic.getUuid())) {
        //            int flag = characteristic.getProperties();
        //            int format = -1;
        //            if ((flag & 0x01) != 0) {
        //                format = BluetoothGattCharacteristic.FORMAT_UINT16;
        //                Log.d(TAG, "Heart rate format UINT16.");
        //            } else {
        //                format = BluetoothGattCharacteristic.FORMAT_UINT8;
        //                Log.d(TAG, "Heart rate format UINT8.");
        //            }
        //            final int heartRate = characteristic.getIntValue(format, 1);
        //            Log.d(TAG, String.format("Received heart rate: %d", heartRate));
        //            intent.putExtra(EXTRA_DATA, String.valueOf(heartRate));
        //        } else {
        // For all other profiles, writes the data formatted in HEX.
        final byte[] data = characteristic.getValue();
        if (data != null && data.length > 0) {
            intent.putExtra(EXTRA_DATA, new String(data));
            sendBroadcast(intent);
        }
        //        }
    }

    private void broadcastUpdate(int rssi) {
        final Intent intent = new Intent(ACTION_DATA_AVAILABLE);
        intent.putExtra("RSSI", rssi);
        sendBroadcast(intent);
    }

    public class LocalBinder extends Binder {
        BluetoothLeService getService() {
            return BluetoothLeService.this;
        }
    }

    @Override
    public IBinder onBind(Intent intent) {
        return mBinder;
    }

    @Override
    public boolean onUnbind(Intent intent) {
        // After using a given device, you should make sure that BluetoothGatt.close() is called
        // such that resources are cleaned up properly.  In this particular example, close() is
        // invoked when the UI is disconnected from the Service.
        close();
        return super.onUnbind(intent);
    }

    private final IBinder mBinder = new LocalBinder();

    /**
     * Initializes a reference to the local Bluetooth adapter.
     *
     * @return Return true if the initialization is successful.
     */
    public boolean initialize() {
        // For API level 18 and above, get a reference to BluetoothAdapter through
        // BluetoothManager.
        System.out.println("BluetoothLeService initialize" + mBluetoothManager);
        if (mBluetoothManager == null) {
            mBluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
            if (mBluetoothManager == null) {
                Log.e(TAG, "Unable to initialize BluetoothManager.");
                return false;
            }
        }

        mBluetoothAdapter = mBluetoothManager.getAdapter();
        if (mBluetoothAdapter != null) {
            mBluetoothAdapter.startLeScan(mLeScanCallback);

        } else {
            Log.e(TAG, "Unable to obtain a BluetoothAdapter.");
            return false;
        }

        return true;
    }

    /**
     * Connects to the GATT server hosted on the Bluetooth LE device.
     *
     * @param address The device address of the destination device.
     *
     * @return Return true if the connection is initiated successfully. The connection result
     *         is reported asynchronously through the
     *         {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
     *         callback.
     */
    public boolean connect(final String address) {
        System.out.println("BluetoothLeService connect" + address + mBluetoothGatt);
        if (mBluetoothAdapter == null || address == null) {
            Log.w(TAG, "BluetoothAdapter not initialized or unspecified address.");
            return false;
        }

        // Previously connected device.  Try to reconnect.
        //        if (mBluetoothDeviceAddress != null && address.equals(mBluetoothDeviceAddress)
        //                && mBluetoothGatt != null) {
        //            Log.d(TAG, "Trying to use an existing mBluetoothGatt for connection.");
        //            if (mBluetoothGatt.connect()) {
        //               System.out.println("mBluetoothGatt connect");
        //                mConnectionState = STATE_CONNECTING;
        //                return true;
        //            } else {
        //               System.out.println("mBluetoothGatt else connect");
        //                return false;
        //            }
        //        }

        final BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
        if (device == null) {
            Log.w(TAG, "Device not found.  Unable to connect.");
            return false;
        }
        // We want to directly connect to the device, so we are setting the autoConnect
        // parameter to false.
        System.out.println("device.connectGatt connect");
        synchronized (this) {
            mBluetoothGatt = device.connectGatt(this, false, mGattCallback);
        }
        Log.d(TAG, "Trying to create a new connection.");
        mBluetoothDeviceAddress = address;
        mConnectionState = STATE_CONNECTING;
        return true;
    }

    /**
     * Disconnects an existing connection or cancel a pending connection. The disconnection result
     * is reported asynchronously through the
     * {@code BluetoothGattCallback#onConnectionStateChange(android.bluetooth.BluetoothGatt, int, int)}
     * callback.
     */
    public void disconnect() {
        System.out.println("BluetoothLeService disconnect");
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }
        mBluetoothGatt.disconnect();
    }

    /**
     * After using a given BLE device, the app must call this method to ensure resources are
     * released properly.
     */
    public void close() {
        System.out.println("BluetoothLeService close");
        if (mBluetoothGatt == null) {
            return;
        }
        mBluetoothGatt.close();
        mBluetoothGatt = null;
    }

    /**
     * Request a read on a given {@code BluetoothGattCharacteristic}. The read result is reported
     * asynchronously through the {@code BluetoothGattCallback#onCharacteristicRead(android.bluetooth.BluetoothGatt, android.bluetooth.BluetoothGattCharacteristic, int)}
     * callback.
     *
     * @param characteristic The characteristic to read from.
     */
    public void readCharacteristic(BluetoothGattCharacteristic characteristic) {
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }
        mBluetoothGatt.readCharacteristic(characteristic);
    }

    /**
     * Write information to the device on a given {@code BluetoothGattCharacteristic}. The content string and characteristic is 
     * only pushed into a ring buffer. All the transmission is based on the {@code onCharacteristicWrite} call back function, 
     * which is called directly in this function
     *
     * @param characteristic The characteristic to write to.
     */
    public void writeCharacteristic(BluetoothGattCharacteristic characteristic) {
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }

        //The character size of TI CC2540 is limited to 17 bytes, otherwise characteristic can not be sent properly,
        //so String should be cut to comply this restriction. And something should be done here:
        String writeCharacteristicString;
        try {
            writeCharacteristicString = new String(characteristic.getValue(), "ISO-8859-1");
        } catch (UnsupportedEncodingException e) {
            // this should never happen because "US-ASCII" is hard-coded.
            throw new IllegalStateException(e);
        }
        System.out.println("allwriteCharacteristicString:" + writeCharacteristicString);

        //As the communication is asynchronous content string and characteristic should be pushed into an ring buffer for further transmission
        mCharacteristicRingBuffer
                .push(new BluetoothGattCharacteristicHelper(characteristic, writeCharacteristicString));
        System.out.println("mCharacteristicRingBufferlength:" + mCharacteristicRingBuffer.size());

        //The progress of onCharacteristicWrite and writeCharacteristic is almost the same. So callback function is called directly here
        //for details see the onCharacteristicWrite function
        mGattCallback.onCharacteristicWrite(mBluetoothGatt, characteristic, WRITE_NEW_CHARACTERISTIC);

    }

    /**
     * Enables or disables notification on a give characteristic.
     *
     * @param characteristic Characteristic to act on.
     * @param enabled If true, enable notification.  False otherwise.
     */
    public void setCharacteristicNotification(BluetoothGattCharacteristic characteristic, boolean enabled) {
        if (mBluetoothAdapter == null || mBluetoothGatt == null) {
            Log.w(TAG, "BluetoothAdapter not initialized");
            return;
        }
        mBluetoothGatt.setCharacteristicNotification(characteristic, enabled);

        //BluetoothGattDescriptor descriptor = characteristic.getDescriptor(characteristic.getUuid());
        //descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
        //mBluetoothGatt.writeDescriptor(descriptor);

        // This is specific to Heart Rate Measurement.
        //        if (UUID_HEART_RATE_MEASUREMENT.equals(characteristic.getUuid())) {
        //            BluetoothGattDescriptor descriptor = characteristic.getDescriptor(
        //                    UUID.fromString(SampleGattAttributes.CLIENT_CHARACTERISTIC_CONFIG));
        //            descriptor.setValue(BluetoothGattDescriptor.ENABLE_NOTIFICATION_VALUE);
        //            mBluetoothGatt.writeDescriptor(descriptor);
        //        }
    }

    /**
     * Retrieves a list of supported GATT services on the connected device. This should be
     * invoked only after {@code BluetoothGatt#discoverServices()} completes successfully.
     *
     * @return A {@code List} of supported services.
     */
    public List<BluetoothGattService> getSupportedGattServices() {
        if (mBluetoothGatt == null)
            return null;

        return mBluetoothGatt.getServices();
    }

    // Device scan callback.
    private BluetoothAdapter.LeScanCallback mLeScanCallback = new BluetoothAdapter.LeScanCallback() {

        @Override
        public void onLeScan(final BluetoothDevice device, final int rssi, byte[] scanRecord) {
            if (device.getName() != null) {
                Log.d("device", device.getName() + "");
                if (device.getName().equals("BlunoV1.8")) {
                    connect(device.getAddress());
                    // Log.d("rssi service",rssi+"");

                }
            }
        }

    };

    private void getGattServices(List<BluetoothGattService> gattServices) {
        if (gattServices == null)
            return;
        String uuid = null;
        mModelNumberCharacteristic = null;
        mSerialPortCharacteristic = null;
        mCommandCharacteristic = null;
        mGattCharacteristics = new ArrayList<ArrayList<BluetoothGattCharacteristic>>();

        // Loops through available GATT Services.
        for (BluetoothGattService gattService : gattServices) {
            uuid = gattService.getUuid().toString();
            System.out.println("displayGattServices + uuid=" + uuid);

            List<BluetoothGattCharacteristic> gattCharacteristics = gattService.getCharacteristics();
            ArrayList<BluetoothGattCharacteristic> charas = new ArrayList<BluetoothGattCharacteristic>();

            // Loops through available Characteristics.
            for (BluetoothGattCharacteristic gattCharacteristic : gattCharacteristics) {
                charas.add(gattCharacteristic);
                uuid = gattCharacteristic.getUuid().toString();
                if (uuid.equals(ModelNumberStringUUID)) {
                    mModelNumberCharacteristic = gattCharacteristic;
                    System.out.println(
                            "mModelNumberCharacteristic  " + mModelNumberCharacteristic.getUuid().toString());
                } else if (uuid.equals(SerialPortUUID)) {
                    mSerialPortCharacteristic = gattCharacteristic;
                    System.out.println(
                            "mSerialPortCharacteristic  " + mSerialPortCharacteristic.getUuid().toString());
                    //                    updateConnectionState(R.string.comm_establish);
                } else if (uuid.equals(CommandUUID)) {
                    mCommandCharacteristic = gattCharacteristic;
                    System.out.println(
                            "mSerialPortCharacteristic  " + mSerialPortCharacteristic.getUuid().toString());
                    //                    updateConnectionState(R.string.comm_establish);
                }
            }
            mGattCharacteristics.add(charas);
        }

        if (mModelNumberCharacteristic == null || mSerialPortCharacteristic == null
                || mCommandCharacteristic == null) {
            Log.d("charactaristics", "null");
            Toast.makeText(getApplicationContext(), "characteristics null", Toast.LENGTH_SHORT);
        } else {
            mSCharacteristic = mModelNumberCharacteristic;
            setCharacteristicNotification(mSCharacteristic, true);
            readCharacteristic(mSCharacteristic);
        }

    }

}