/*
* 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 com.example.android.BluetoothChat;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
/**
* 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 BluetoothChatService
{
// Debugging
private static final String TAG = "BluetoothChatService";
private static final boolean D = true;
// Name for the SDP record when creating server socket
private static final String NAME_SECURE = "BluetoothChatSecure";
private static final String NAME_INSECURE = "BluetoothChatInsecure";
// Unique UUID for this application
private static final UUID MY_UUID_SECURE = UUID
.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
private static final UUID MY_UUID_INSECURE = UUID
.fromString("8ce255c0-200a-11e0-ac64-0800200c9a66");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private AcceptThread mSecureAcceptThread;
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
*/
public BluetoothChatService(Context context, Handler handler)
{
// We get the default bluetooth service.
mAdapter = BluetoothAdapter.getDefaultAdapter();
// Default to no state
mState = STATE_NONE;
// Define the handler which can return results to the activity
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);
// Start the thread to listen on a BluetoothServerSocket
if (mSecureAcceptThread == null)
{
mSecureAcceptThread = new AcceptThread(true);
mSecureAcceptThread.start();
}
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 (mSecureAcceptThread != null)
{
mSecureAcceptThread.cancel();
mSecureAcceptThread = null;
}
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 (mSecureAcceptThread != null)
{
mSecureAcceptThread.cancel();
mSecureAcceptThread = 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 ConnectedThread#write(byte[])
*/
public 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
BluetoothChatService.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
BluetoothChatService.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
{
if (secure)
{
tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME_SECURE, MY_UUID_SECURE);
} else
{
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 (BluetoothChatService.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
{
if (secure)
{
tmp = device.createRfcommSocketToServiceRecord(MY_UUID_SECURE);
} else
{
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 (BluetoothChatService.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;
}
public void run()
{
Log.i(TAG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (true)
{
try
{
// Read from the InputStream
bytes = mmInStream.read(buffer);
// 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
BluetoothChatService.this.start();
break;
}
}
}
/**
* Write to the connected OutStream.
*
* @param buffer
* The bytes to write
*/
public void write(byte[] buffer)
{
try
{
mmOutStream.write(buffer);
// Share the sent message back to the UI Activity
mHandler.obtainMessage(BluetoothChat.MESSAGE_WRITE, -1, -1, buffer).sendToTarget();
} 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);
}
}
}
}