如何从客户端通过蓝牙将字符串发送到移动服务器?

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怎么通过蓝牙将一条字符串从PC传输到Android移动设备?Android移动设备应该充当服务器,并在设备的屏幕上显示字符串消息。作为客户端的PC机应该将字符串发送到移动设备。

我希望服务器对提取的字符串做出反应(通过蓝牙传输)。这意味着,在一个端,服务器总是要侦听新的字符串到达,但在另一端仍然必须能够对这些消息作出反应(例如,从一个菜单导航到另一个菜单)。

我尝试使用BlueCove(2.1.1)作为蓝牙Stack(为此,我将BlueecLove中的JAR作为库添加到两个项目中),并结合我在其中找到的服务器-客户端通信示例:http://www.jsr82.com/jsr-82-sam-spp-server-and-client/

服务器更新了代码,使用服务器的RFComm连接

public class RFCommServer extends Thread{

//based on java.util.UUID
private static UUID MY_UUID = UUID.fromString("446118f0-8b1e-11e2-9e96-0800200c9a66");

// The local server socket
private BluetoothServerSocket mmServerSocket;

// based on android.bluetooth.BluetoothAdapter
private BluetoothAdapter mAdapter;
private BluetoothDevice remoteDevice;

private Activity activity;

public RFCommServer(Activity activity) {
    this.activity = activity;
}

public void run() {
    BluetoothSocket socket = null;
    mAdapter = BluetoothAdapter.getDefaultAdapter();        

    // Listen to the server socket if we're not connected
    while (true) {

        try {
            // Create a new listening server socket
            Log.d(this.getName(), ".....Initializing RFCOMM SERVER....");

            // MY_UUID is the UUID you want to use for communication
            mmServerSocket = mAdapter.listenUsingRfcommWithServiceRecord("MyService", MY_UUID);
            //mmServerSocket = mAdapter.listenUsingInsecureRfcommWithServiceRecord(NAME, MY_UUID); // you can also try using In Secure connection...

            // This is a blocking call and will only return on a
            // successful connection or an exception
            socket = mmServerSocket.accept();

        } catch (Exception e) {

        }

        try {
            Log.d(this.getName(), "Closing Server Socket.....");
            mmServerSocket.close();

            InputStream tmpIn = null;
            OutputStream tmpOut = null;

            // Get the BluetoothSocket input and output streams

            tmpIn = socket.getInputStream();
            tmpOut = socket.getOutputStream();

            DataInputStream mmInStream = new DataInputStream(tmpIn);
            DataOutputStream mmOutStream = new DataOutputStream(tmpOut);

            // here you can use the Input Stream to take the string from the client whoever is connecting
            //similarly use the output stream to send the data to the client

            RelativeLayout layout = (RelativeLayout) activity.findViewById(R.id.relativeLayout_Layout);
            TextView text = (TextView) layout.findViewById(R.id.textView_Text);

            text.setText(mmInStream.toString());
        } catch (Exception e) {
            //catch your exception here
        }
    }
}

SPP客户端代码http://www.jsr82.com/jsr-82-sam-spp-server-and-client/

/**
* A simple SPP client that connects with an SPP server
*/
public class SampleSPPClient implements DiscoveryListener{

//object used for waiting
private static Object lock=new Object();

//vector containing the devices discovered
private static Vector vecDevices=new Vector();

private static String connectionURL=null;

public static void main(String[] args) throws IOException {

    SampleSPPClient client=new SampleSPPClient();

    //display local device address and name
    LocalDevice localDevice = LocalDevice.getLocalDevice();
    System.out.println("Address: "+localDevice.getBluetoothAddress());
    System.out.println("Name: "+localDevice.getFriendlyName());

    //find devices
    DiscoveryAgent agent = localDevice.getDiscoveryAgent();

    System.out.println("Starting device inquiry...");
    agent.startInquiry(DiscoveryAgent.GIAC, client);

    try {
        synchronized(lock){
            lock.wait();
        }
    }
    catch (InterruptedException e) {
        e.printStackTrace();
    }


    System.out.println("Device Inquiry Completed. ");

    //print all devices in vecDevices
    int deviceCount=vecDevices.size();

    if(deviceCount <= 0){
        System.out.println("No Devices Found .");
        System.exit(0);
    }
    else{
        //print bluetooth device addresses and names in the format [ No. address (name) ]
        System.out.println("Bluetooth Devices: ");
        for (int i = 0; i <deviceCount; i++) {
            RemoteDevice remoteDevice=(RemoteDevice)vecDevices.elementAt(i);
            System.out.println((i+1)+". "+remoteDevice.getBluetoothAddress()+" ("+remoteDevice.getFriendlyName(true)+")");
        }
    }

    System.out.print("Choose Device index: ");
    BufferedReader bReader=new BufferedReader(new InputStreamReader(System.in));

    String chosenIndex=bReader.readLine();
    int index=Integer.parseInt(chosenIndex.trim());

    //check for spp service
    RemoteDevice remoteDevice=(RemoteDevice)vecDevices.elementAt(index-1);
    UUID[] uuidSet = new UUID[1];
    uuidSet[0]=new UUID("446118f08b1e11e29e960800200c9a66", false);

    System.out.println("\nSearching for service...");
    agent.searchServices(null,uuidSet,remoteDevice,client);

    try {
        synchronized(lock){
            lock.wait();
        }
    }
    catch (InterruptedException e) {
        e.printStackTrace();
    }

    if(connectionURL==null){
        System.out.println("Device does not support Simple SPP Service.");
        System.exit(0);
    }

    //connect to the server and send a line of text
    StreamConnection streamConnection=(StreamConnection)Connector.open(connectionURL);

    //send string
    OutputStream outStream=streamConnection.openOutputStream();
    PrintWriter pWriter=new PrintWriter(new OutputStreamWriter(outStream));
    pWriter.write("Test String from SPP Client\r\n");
    pWriter.flush();


    //read response
    InputStream inStream=streamConnection.openInputStream();
    BufferedReader bReader2=new BufferedReader(new InputStreamReader(inStream));
    String lineRead=bReader2.readLine();
    System.out.println(lineRead);


}//main

//methods of DiscoveryListener
public void deviceDiscovered(RemoteDevice btDevice, DeviceClass cod) {
    //add the device to the vector
    if(!vecDevices.contains(btDevice)){
        vecDevices.addElement(btDevice);
    }
}

//implement this method since services are not being discovered
public void servicesDiscovered(int transID, ServiceRecord[] servRecord) {
    if(servRecord!=null && servRecord.length>0){
        connectionURL=servRecord[0].getConnectionURL(0,false);
    }
    synchronized(lock){
        lock.notify();
    }
}

//implement this method since services are not being discovered
public void serviceSearchCompleted(int transID, int respCode) {
    synchronized(lock){
        lock.notify();
    }
}


public void inquiryCompleted(int discType) {
    synchronized(lock){
        lock.notify();
    }

}//end method

}

为了进行测试,我使用了GalaxyNexus(GT-I 9250)和最新的AndroidAPI。

客户端和服务器无异常地运行。但遗憾的是,客户端无法连接到服务器(见屏幕截图)。这是因为始终没有设置connectionURL(因此,默认情况下它跳到这里“if(connectionURL=null)”。

如何更改客户端代码,以便能够将其实际连接到服务器?我需要一个正确的连接URL,如下行所示:StreamConnection streamConnection=(StreamConnection)Connector.open(connectionURL).到目前为止,我只发现我需要得到ServiceRecord,遗憾的是,在示例代码中也没有对此进行描述。http://www.jsr82.com/jsr-82-sam-spp-server-and-client/

提问于
用户回答回答于

需要使用RFCommAPI来使通信工作,我已经定义了一个类,它是一个线程,它将充当服务器并侦听客户端连接。

    private class AcceptThread extends Thread {
    // The local server socket
    private BluetoothServerSocket mmServerSocket;

    public AcceptThread() {
    }

    public void run() {         
        BluetoothSocket socket = null;

                    BluetoothAdapter mAdapter = BluetoothAdapter.getDefaultAdapter();

        // Listen to the server socket if we're not connected
        while (true) {

            try {
                // Create a new listening server socket
                Log.d(TAG, ".....Initializing RFCOMM SERVER....");

                // MY_UUID is the UUID you want to use for communication
                mmServerSocket = mAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);                    
                //mmServerSocket = mAdapter.listenUsingInsecureRfcommWithServiceRecord(NAME, MY_UUID);  you can also try using In Secure connection...

                // This is a blocking call and will only return on a
                // successful connection or an exception                    
                socket = mmServerSocket.accept();                   

            } catch (Exception e) {

            }

            try {
                Log.d(TAG, "Closing Server Socket.....";                    
                mmServerSocket.close();



                InputStream tmpIn = null;
                OutputStream tmpOut = null;

                // Get the BluetoothSocket input and output streams

                tmpIn = socket.getInputStream();
                tmpOut = socket.getOutputStream();


                mmInStream = new DataInputStream(tmpIn);
                mmOutStream = new DataOutputStream(tmpOut); 

                // here you can use the Input Stream to take the string from the client whoever is connecting
                //similarly use the output stream to send the data to the client
            } catch (Exception e) {
                //catch your exception here
            }

        }
    }

}

在客户端(PC)UUID类声明javax.bluetooth.UUID

   uuidSet2[0] = new UUID("446118f08b1e11e29e960800200c9a66", false);

在服务器端(Android)声明java.util.UUID

    UUID MY_UUID = UUID.fromString("446118f0-8b1e-11e2-9e96-0800200c9a66");
用户回答回答于

SPP的UUID应该是"00001101-0000-1000-8000-00805F9B34FB"

这是一个标识蓝牙SPP适配器的UID。

在我的c#代码中

private static UUID MY_UUID = UUID.FromString("00001101-0000-1000-8000-00805F9B34FB");

我猜你可以更新Java代码如下:

new UUID("00001101-0000-1000-8000-00805F9B34FB", true);

如下:

btAdapter = BluetoothAdapter.DefaultAdapter;

btAdapter.CancelDiscovery(); //Always call CancelDiscovery before doing anything
remoteDevice = btAdapter.GetRemoteDevice(Settings["deviceaddress"].ToString());

socket = remoteDevice.CreateRfcommSocketToServiceRecord(MY_UUID);
socket.Connect();

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