蓝牙android服务器插座问题

Question

我在为我的蓝牙应用程序构建客户端服务器模型时遇到了很大的问题。我在手机上运行蓝牙服务器应用程序。代码如下:公共类BlueSer扩展了Activity {

 /** Called when the activity is first created. */
 private BluetoothAdapter mBluetoothAdapter = null;
 private static final UUID MY_UUID =
 UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
 private byte[] buffer = new byte[8192];
 private ImageView image;

 @Override
 public void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.blueserv);
 image = (ImageView) findViewById(R.id.imageView1);

 mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
 if (mBluetoothAdapter == null) {
 Toast.makeText(this,
 "Bluetooth is not available.",
 Toast.LENGTH_LONG).show();
 finish();
 return;
 }

if (!mBluetoothAdapter.isEnabled()) {
 Toast.makeText(this,
 "Please enable your BT and re-run this program.",
 Toast.LENGTH_LONG).show();
 finish();
 return;
 }
Log.w("Thread Started: ", "Thread ka start hai jani");
 AcceptData acceptData = new AcceptData();
 acceptData.start();
 Bitmap bm1 = BitmapFactory.decodeByteArray(buffer, 0, buffer.length);
 image.setImageBitmap(bm1);
 }

 class AcceptData extends Thread{
 private final BluetoothServerSocket mmServerSocket;
 private BluetoothSocket socket = null;
 private InputStream mmInStream;
 private String device;
 public AcceptData() {
 BluetoothServerSocket tmp = null;
 try {
 tmp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord("Bluetooth", MY_UUID);
 } catch (IOException e) {
     Log.w("Display Hona Chahye", "Kr dia na display Rami");
 //
 }
 mmServerSocket = tmp;
 try {
 socket = mmServerSocket.accept();
 } catch (IOException e) {
 //
 }
 Log.w("iudfghiue", "yaiiii");
 device = socket.getRemoteDevice().getName();
 Toast.makeText(getBaseContext(), "Connected to " + device, Toast.LENGTH_SHORT).show();
 InputStream tmpIn = null;
 try {
 tmpIn = socket.getInputStream();
 } catch (IOException e) {
 //
 }
 mmInStream = tmpIn;
 int byteNo;
 try {
 byteNo = mmInStream.read(buffer);
 if (byteNo != -1) {
 //ensure DATAMAXSIZE Byte is read.
 int byteNo2 = byteNo;
 int bufferSize = 7340;
 while(byteNo2 != bufferSize){
 bufferSize = bufferSize - byteNo2;
 byteNo2 = mmInStream.read(buffer,byteNo,bufferSize);
 if(byteNo2 == -1){
 break;
 }
 byteNo = byteNo+byteNo2;
 }
 }
 if (socket != null) {
 try {
 mmServerSocket.close();
 } catch (IOException e) {
 //
 }
 }
 }
 catch (Exception e) {
 // TODO: handle exception
 }
}
}

}

logcat如下：

12-23 01:32:34.292: D/ServiceManager(1264): The name of the service is bluetooth
12-23 01:32:34.293: W/Thread Started:(1264): Thread ka start hai jani
12-23 01:32:34.294: I/BluetoothSocket_MTK(1264): [JSR82] Bluetooth Socket Constructor
12-23 01:32:34.294: I/BluetoothSocket_MTK(1264): [JSR82] type=1 fd=-1 auth=true encrypt=true port=4
12-23 01:32:34.294: D/ServiceManager(1264): The name of the service is bluetooth_socket
**12-23 01:32:34.295: I/BluetoothSocket_MTK(1264): [JSR82] bindListen
12-23 01:32:34.296: D/BluetoothSocket_MTK(1264): [JSR82] bindListen: bindListen() failed.
12-23 01:32:34.298: I/BluetoothSocket_MTK(1264): [JSR82] accept().
12-23 01:32:34.299: I/BluetoothSocket_MTK(1264): [JSR82] accept: Connection is not created.**
12-23 01:32:34.299: W/iudfghiue(1264): yaiiii
12-23 01:32:34.299: D/AndroidRuntime(1264): Shutting down VM
12-23 01:32:34.299: W/dalvikvm(1264): threadid=1: thread exiting with uncaught exception (group=0x413ad9a8)
12-23 01:32:34.305: E/AndroidRuntime(1264): FATAL EXCEPTION: main
12-23 01:32:34.305: E/AndroidRuntime(1264): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.BlueSer/com.example.blueserv.BlueSer}: java.lang.NullPointerException
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2313)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2365)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.app.ActivityThread.access$600(ActivityThread.java:156)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.os.Handler.dispatchMessage(Handler.java:99)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.os.Looper.loop(Looper.java:153)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at android.app.ActivityThread.main(ActivityThread.java:5336)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at java.lang.reflect.Method.invokeNative(Native Method)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at java.lang.reflect.Method.invoke(Method.java:511)
12-23 01:32:34.305: E/AndroidRuntime(1264):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:833)

现在，如果我把注意力放在logcat上，我的程序会抛出异常，因为它不能侦听某些设备。我已经将该设备与另一台android设备配对。就是搞不清楚问题出在哪里。请帮帮忙。这些似乎是代码中令人不安的几行代码：

tmp = mBluetoothAdapter.listenUsingRfcommWithServiceRecord("Bluetooth", MY_UUID);
         } catch (IOException e) {
             Log.w("Display Hona Chahye", "Kr dia na display Rami");
         //
         }
         mmServerSocket = tmp;
         try {
         socket = mmServerSocket.accept();

我在客户端和服务器代码中保持UUID的字符串相同！

Answer 1

这适用于我，或者您可以参考this库以了解有关流程的更多详细信息

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 com.example.android.common.logger.Log;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;

/**
 * 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";

    // 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) {
        mAdapter = BluetoothAdapter.getDefaultAdapter();
        mState = STATE_NONE;
        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) {
        Log.d(TAG, "setState() " + mState + " -> " + state);
        mState = state;

        // Give the new state to the Handler so the UI Activity can update
        mHandler.obtainMessage(Constants.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() {
        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) {
        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) {
        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(Constants.MESSAGE_DEVICE_NAME);
        Bundle bundle = new Bundle();
        bundle.putString(Constants.DEVICE_NAME, device.getName());
        msg.setData(bundle);
        mHandler.sendMessage(msg);

        setState(STATE_CONNECTED);
    }

    /**
     * Stop all threads
     */
    public synchronized void stop() {
        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(Constants.MESSAGE_TOAST);
        Bundle bundle = new Bundle();
        bundle.putString(Constants.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(Constants.MESSAGE_TOAST);
        Bundle bundle = new Bundle();
        bundle.putString(Constants.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() {
            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;
                        }
                    }
                }
            }
            Log.i(TAG, "END mAcceptThread, socket Type: " + mSocketType);

        }

        public void cancel() {
            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(Constants.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(Constants.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);
            }
        }
    }
}