我正在开发 2 个必须使用蓝牙和 WiFi P2P 以 JSON 格式交换某种数据的 Android 应用程序。
蓝牙部分进展顺利，一切正常。
问题出现在 WiFi P2P 实现中，因为我无法连接套接字以交换数据。这些设备使用 WiFi-P2P 连接良好，但问题在于 Socket 编程级别。
我没有收到任何错误消息，但 ServerSocket 从未收到连接请求。我已经检查过，来自服务器应用程序端的 ServerSocket 和来自客户端应用程序端的 Socket 都绑定到相同的 IP 地址：192.168.49.1 端口 8989。
任何有关我的代码可能有问题的帮助将不胜感激。
这是作为服务器的应用程序上的代码：
public class WiFiIO {
private static final String LOG = "UJUKE-CONTROLLER-WIFI-IO";
public static int SERVER_PORT = 8989;
public String IP = "";
private final Handler mHandler;
private AcceptThread mAcceptThread;
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
// Message types sent from the BluetoothChatService Handler
public static final int MESSAGE_STATE_CHANGE = 1;
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
public static final int MESSAGE_DEVICE_NAME = 4;
public static final int MESSAGE_TOAST = 5;
// Key names received from the BluetoothChatService Handler
public static final String DEVICE_NAME = "device_name";
public static final String TOAST = "toast";
/**
* Constructor. Prepares a new WiFi session.
*
* @param context The UI Activity Context
* @param handler A Handler to send messages back to the UI Activity
*/
public WiFiIO(Context context,
Handler handler) {
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(LOG, "setState() " + mState + " -> " + state);
mState = state;
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
/**
* Return the current connection state.
*/
public synchronized int getState() {
return mState;
}
/**
* Start the lisen service. Specifically start AcceptThread to begin a
* session in listening (server) mode. Called by the Activity onResume()
*/
public synchronized void start(String ip) {
Log.d(LOG, "start");
IP = ip;
// Cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
setState(STATE_LISTEN);
// Start the thread to listen on a ServerSocket
if (mAcceptThread == null) {
mAcceptThread = new AcceptThread();
mAcceptThread.start();
}
}
/**
* Start the ConnectedThread to begin managing a wi-fi connection
*
*/
public synchronized void connected(Socket socket) {
//Log.d(LOG, "connected to " + mConfig.deviceAddress);
Log.d(LOG, "connected");
// 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 (mAcceptThread != null) {
mAcceptThread.cancel();
mAcceptThread = null;
}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket, socket.getRemoteSocketAddress());
mConnectedThread.start();
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(DEVICE_NAME, "device");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* Stop all threads
*/
public synchronized void stop() {
Log.d(LOG, "stop");
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
if (mAcceptThread != null) {
mAcceptThread.cancel();
mAcceptThread = 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 was lost and notify the UI Activity.
*/
private void connectionLost() {
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);
// Start the service over to restart listening mode
WiFiIO.this.start(IP);
}
/**
* 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 ServerSocket mmServerSocket;
public AcceptThread() {
ServerSocket tmp = null;
// Create a new listening server socket
try {
tmp = new ServerSocket(SERVER_PORT);
//tmp = new ServerSocket(SERVER_PORT,50,InetAddress.getByName(IP));
} catch (IOException e) {
Log.e(LOG, "Socket listen() failed", e);
}
mmServerSocket = tmp;
}
public void run() {
Log.d(LOG, "Socket BEGIN mAcceptThread" + this);
setName("AcceptThread");
Socket 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
Log.e(LOG, "Socket server bonded to ip" + mmServerSocket.getInetAddress().toString());
socket = mmServerSocket.accept();
} catch (IOException e) {
Log.e(LOG, "Socket Type accept() failed", e);
//break;
}
// If a connection was accepted
if (socket != null) {
synchronized (WiFiIO.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
// Situation normal. Start the connected thread.
connected(socket);
break;
case STATE_NONE:
case STATE_CONNECTED:
// Either not ready or already connected. Terminate new socket.
try {
socket.close();
} catch (IOException e) {
Log.e(LOG, "Could not close unwanted socket", e);
}
break;
}
}
}
}
Log.i(LOG, "END mAcceptThread, socket Type");
}
public void cancel() {
Log.d(LOG, "Socket Type cancel " + this);
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(LOG, "Socket Type close() of server 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 Socket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(Socket socket, SocketAddress address) {
Log.d(LOG, "create ConnectedThread: ");
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(LOG, "temp sockets not created", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
Log.i(LOG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (true) {
try {
int timeout = 0;
int maxTimeout = 32; // leads to a timeout of 2 seconds
int available = 0;
while((available = mmInStream.available()) == 0 && timeout < maxTimeout) {
timeout++;
// throws interrupted exception
try {
Thread.sleep(250);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
// Read from the InputStream
buffer = new byte[available];
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(LOG, "disconnected", e);
connectionLost();
// Start the service over to restart listening mode
WiFiIO.this.start(IP);
break;
}
}
}
/**
* Write to the connected OutStream.
*
* @param buffer The bytes to write
*/
public void write(byte[] buffer) {
try {
//mmOutStream.write(buffer);
mmOutStream.write(buffer,0,buffer.length);
mmOutStream.flush();
// Share the sent message back to the UI Activity
mHandler.obtainMessage(MESSAGE_WRITE, -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(LOG, "Exception during write", e);
}
}
public void cancel() {
try {
mmOutStream.close();
mmInStream.close();
mmSocket.close();
} catch (IOException e) {
Log.e(LOG, "close() of connect socket failed", e);
}
}
}
}
这是作为客户端的应用程序上的代码：
public class WiFiIO {
private static final String LOG = "UJUKE-CONTROLLER-WIFI-IO";
public static int SERVER_PORT = 8989;
private final Handler mHandler;
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
// Message types sent from the BluetoothChatService Handler
public static final int MESSAGE_STATE_CHANGE = 1;
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
public static final int MESSAGE_DEVICE_NAME = 4;
public static final int MESSAGE_TOAST = 5;
// Key names received from the BluetoothChatService Handler
public static final String DEVICE_NAME = "device_name";
public static final String TOAST = "toast";
/**
* Constructor. Prepares a new WiFi session.
*
* @param context The UI Activity Context
* @param handler A Handler to send messages back to the UI Activity
*/
public WiFiIO(Handler handler) {
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(LOG, "setState() " + mState + " -> " + state);
mState = state;
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
/**
* Return the current connection state.
*/
public synchronized int getState() {
return mState;
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
*
* @param device The IP address to connect
*/
public synchronized void connect(String ip) {
Log.d(LOG, "connect to: " + ip);
// 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(ip);
mConnectThread.start();
setState(STATE_CONNECTING);
}
/**
* Start the ConnectedThread to begin managing a WiFi connection
*
* @param socket The Socket on which the connection was made
*/
public synchronized void connected(Socket socket) {
Log.d(LOG, "connected, Socket Type");
// 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;
}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
mConnectedThread.start();
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(DEVICE_NAME, socket.getRemoteSocketAddress().toString());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
/**
* Stop all threads
*/
public synchronized void stop() {
Log.d(LOG, "stop");
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = 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() {
setState(STATE_NONE);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* 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(MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* 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 Socket mmSocket;
private final String mmIP;
public ConnectThread(String ip) {
Socket tmp = null;
// Get a Socket for a connection with the
// given ip
//try {
tmp = new Socket();
//} catch (IOException e) {
// Log.e(LOG, "Socket Type: create() failed", e);
//}
mmSocket = tmp;
mmIP = ip;
}
public void run() {
Log.i(LOG, "BEGIN mConnectThread ");
setName("ConnectThread");
// Make a connection to the ServerSocket
try {
// This is a blocking call and will only return on a
// successful connection or an exception
while(mmSocket.isConnected() == false){
try{
mmSocket.bind(null);
mmSocket.connect((new InetSocketAddress(mmIP, SERVER_PORT)),0);
}catch (IOException e) {
Log.e(LOG, "unable to connect to server socket", e);
}
}
} catch (Exception e) {
// Close the socket
try {
mmSocket.close();
} catch (IOException e2) {
Log.e(LOG, "unable to close() socket during connection failure", e2);
}
connectionFailed();
return;
}
// Reset the ConnectThread because we're done
synchronized (WiFiIO.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(LOG, "close() of connect 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 Socket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(Socket socket) {
Log.d(LOG, "create ConnectedThread");
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the Socket input and output streams
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.e(LOG, "temp sockets not created", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
if(mmOutStream != null){
String s = "start";
write(s.getBytes());
}
}
public void run() {
Log.i(LOG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (true) {
try {
int timeout = 0;
int maxTimeout = 32; // leads to a timeout of 2 seconds
int available = 0;
while((available = mmInStream.available()) == 0 && timeout < maxTimeout) {
timeout++;
// throws interrupted exception
try {
Thread.sleep(250);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
// Read from the InputStream
buffer = new byte[available];
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(LOG, "disconnected", e);
connectionLost();
break;
}
}
}
/**
* Write to the connected OutStream.
*
* @param buffer The bytes to write
*/
public void write(byte[] buffer) {
try {
mmOutStream.write(buffer);
mmOutStream.flush();
// Share the sent message back to the UI Activity
mHandler.obtainMessage(MESSAGE_WRITE, -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(LOG, "Exception during write", e);
}
}
public void cancel() {
try {
mmOutStream.close();
mmInStream.close();
mmSocket.close();
} catch (IOException e) {
Log.e(LOG, "close() of connect socket failed", e);
}
}
}
}