Java Android蓝牙套接字.connect（）；IOException

我正在尝试通过蓝牙连接两个设备。配对过程是通过android native stuff完成的，这意味着我只需要获取套接字本身并在此套接字上调用.connect（）

我们的目标是创建一个蓝牙系统来处理主/辅关系（多个辅节点向主节点发送数据）

这是我目前的代码：

import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Handler;
import android.support.annotation.Nullable;
import android.util.Log;

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

public final class BluetoothLogic {

private final Handler mHandler;

public BluetoothLogic(Handler handler) {
    mHandler = handler;
}

@Nullable
public ConnectedThread getMaster() {
    BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    bluetoothAdapter.cancelDiscovery();
    ArrayList<BluetoothDevice> pairedDevices = new ArrayList<>(bluetoothAdapter.getBondedDevices());

    if (pairedDevices.size() > 0) {
        BluetoothDevice device = pairedDevices.get(0);
        BluetoothSocket socket = null;
        try {
            socket = device.createRfcommSocketToServiceRecord(device.getUuids()[0].getUuid());
            socket.connect();
            return new ConnectedThread(socket);
        } catch (IOException e) {
            e.printStackTrace();

            try {
                if(socket != null) {
                    socket.close();
                }
            } catch (IOException e1) {
                e1.printStackTrace();
            }
        }
        return null;
    } else {
        Log.d(BluetoothLogic.class.getName(), "No connected devices");
        return null;
    }
}

@Nullable
public ArrayList<ConnectedThread> getWorker() {
    ArrayList<ConnectedThread> threads = new ArrayList<>();
    BluetoothAdapter bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    bluetoothAdapter.cancelDiscovery();
    ArrayList<BluetoothDevice> pairedDevices = new ArrayList<>(bluetoothAdapter.getBondedDevices());

    if (pairedDevices.size() > 0) {
        for (BluetoothDevice device : pairedDevices) {
            BluetoothSocket socket = null;
            try {
                socket = device.createRfcommSocketToServiceRecord(device.getUuids()[0].getUuid());
                socket.connect();
                threads.add(new ConnectedThread(socket));
            } catch (IOException e) {
                e.printStackTrace();

                try {
                    if(socket != null) {
                        socket.close();
                    }
                } catch (IOException e1) {
                    e1.printStackTrace();
                }
            }
        }

        if(!threads.isEmpty()) {
            return threads;
        } else {
            return null;
        }
    } else {
        Log.d(BluetoothLogic.class.getName(), "No connected devices");
        return null;
    }
}

public class ConnectedThread extends Thread {
    private final BluetoothSocket mmSocket;
    private final InputStream mmInStream;
    private final OutputStream mmOutStream;

    public ConnectedThread(BluetoothSocket socket) {
        mmSocket = socket;
        InputStream tmpIn = null;
        OutputStream tmpOut = null;

        try {
            tmpIn = mmSocket.getInputStream();
            tmpOut = mmSocket.getOutputStream();
        } catch (IOException e) {
            e.printStackTrace();
        }

        mmInStream = tmpIn;
        mmOutStream = tmpOut;
    }

    public void run() {
        byte[] buffer = new byte[20];  // buffer store for the stream
        int bytes; // bytes returned from read()

        // Keep listening to the InputStream until an exception occurs
        while (true) {
            try {
                // Read from the InputStream
                bytes = mmInStream.read(buffer);
                // Send the obtained bytes to the UI activity
                mHandler.obtainMessage(0, bytes, -1, buffer).sendToTarget();
            } catch (IOException e) {
                e.printStackTrace();
                break;
            }
        }
    }

    /* Call this from the main activity to send data to the remote device */
    public void write(byte[] bytes) {
        try {
            mmOutStream.write(bytes);
        } catch (IOException e) {
        }
    }

    /* Call this from the main activity to shutdown the connection */
    public void cancel() {
        try {
            mmSocket.close();
        } catch (IOException e) {
        }
    }
}
}

我还尝试使用以下方法实施经常建议的解决方案：

createMethod = device.getClass().getMethod("createInsecureRfcommSocket", new Class[] { int.class });
sock = (BluetoothSocket)createMethod.invoke(device, 1);

我用于测试的两个设备是Nexus5和Nexus5x。我希望有人能帮我解决我的问题。：）

更新：

根据logcat，插座在打开之前已关闭：

.....
04-30 20:53:56.022 4754-4754/? I/BTConnectionReceiver: onReceive(context, Intent { act=android.bluetooth.device.action.ACL_CONNECTED flg=0x4000010 cmp=com.google.android.googlequicksearchbox/com.google.android.search.core.service.BluetoothConnectionReceiver (has extras) }, [BluetoothDevice: address=CC:FA:00:54:17:51, alias=null, name=Nexus 5, majorDeviceClass=512, deviceClass=524]
04-30 20:53:56.025 4754-4754/? I/BluetoothClassifier: Bluetooth Device Name: Nexus 5
04-30 20:53:56.308 5785-5849/? W/bt_rfcomm: port_rfc_closed RFCOMM connection in state 1 closed: Closed (res: 19)
04-30 20:53:56.309 10462-10462/com.thm.sensors W/System.err: java.io.IOException: read failed, socket might closed or timeout, read ret: -1
04-30 20:53:56.309 5785-5853/? E/bt_btif_sock_rfcomm: find_rfc_slot_by_id unable to find RFCOMM slot id: 8
....

---

这怎么可能呢？

你找到解决办法了吗？老实说，我真的说不出来。我想这是我如何打开不同插座的问题。如果您想看一下，下面是源代码：

.....
04-30 20:53:56.022 4754-4754/? I/BTConnectionReceiver: onReceive(context, Intent { act=android.bluetooth.device.action.ACL_CONNECTED flg=0x4000010 cmp=com.google.android.googlequicksearchbox/com.google.android.search.core.service.BluetoothConnectionReceiver (has extras) }, [BluetoothDevice: address=CC:FA:00:54:17:51, alias=null, name=Nexus 5, majorDeviceClass=512, deviceClass=524]
04-30 20:53:56.025 4754-4754/? I/BluetoothClassifier: Bluetooth Device Name: Nexus 5
04-30 20:53:56.308 5785-5849/? W/bt_rfcomm: port_rfc_closed RFCOMM connection in state 1 closed: Closed (res: 19)
04-30 20:53:56.309 10462-10462/com.thm.sensors W/System.err: java.io.IOException: read failed, socket might closed or timeout, read ret: -1
04-30 20:53:56.309 5785-5853/? E/bt_btif_sock_rfcomm: find_rfc_slot_by_id unable to find RFCOMM slot id: 8
....