我已成功配对并与蓝牙设备连接。我现在有兴趣接收在2和之间转移的所有数据。看看是什么。
我从套接字获取输入流并尝试读取它。我将此返回并记录下来。
我从我读过的内容中知道这样做的唯一方法就是用字节缓冲区读取以返回int。但是我应该有大量数据通过。我怎样才能不断读出传输的数据，并将其格式化为字节而不是int。
感谢。
以下完整代码：
public class ConnectThread {
private BluetoothSocketWrapper bluetoothSocket;
private BluetoothDevice device;
private boolean secure;
private BluetoothAdapter adapter;
private List<UUID> uuidCandidates;
private int candidate;
/**
* @param device the device
* @param secure if connection should be done via a secure socket
* @param adapter the Android BT adapter
* @param uuidCandidates a list of UUIDs. if null or empty, the Serial PP id is used
*/
public ConnectThread(BluetoothDevice device, boolean secure, BluetoothAdapter adapter,
List<UUID> uuidCandidates) {
this.device = device;
this.secure = secure;
this.adapter = adapter;
this.uuidCandidates = uuidCandidates;
if (this.uuidCandidates == null || this.uuidCandidates.isEmpty()) {
this.uuidCandidates = new ArrayList<UUID>();
this.uuidCandidates.add(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
}
}
public BluetoothSocketWrapper connect() throws IOException {
boolean success = false;
while (selectSocket()) {
adapter.cancelDiscovery();
try {
bluetoothSocket.connect();
success = true;
break;
} catch (IOException e) {
//try the fallback
try {
bluetoothSocket = new FallbackBluetoothSocket(bluetoothSocket.getUnderlyingSocket());
Thread.sleep(500);
bluetoothSocket.connect();
success = true;
break;
} catch (FallbackException e1) {
Log.w("BT", "Could not initialize FallbackBluetoothSocket classes.", e);
} catch (InterruptedException e1) {
Log.w("BT", e1.getMessage(), e1);
} catch (IOException e1) {
Log.w("BT", "Fallback failed. Cancelling.", e1);
}
}
}
if (!success) {
throw new IOException("Could not connect to device: "+ device.getAddress());
}
receiveData(bluetoothSocket);
return bluetoothSocket;
}
private boolean selectSocket() throws IOException {
if (candidate >= uuidCandidates.size()) {
return false;
}
BluetoothSocket tmp;
UUID uuid = uuidCandidates.get(candidate++);
Log.i("BT", "Attempting to connect to Protocol: "+ uuid);
if (secure) {
tmp = device.createRfcommSocketToServiceRecord(uuid);
} else {
tmp = device.createInsecureRfcommSocketToServiceRecord(uuid);
}
bluetoothSocket = new NativeBluetoothSocket(tmp);
return true;
}
public static interface BluetoothSocketWrapper {
InputStream getInputStream() throws IOException;
OutputStream getOutputStream() throws IOException;
String getRemoteDeviceName();
void connect() throws IOException;
String getRemoteDeviceAddress();
void close() throws IOException;
BluetoothSocket getUnderlyingSocket();
}
public static class NativeBluetoothSocket implements BluetoothSocketWrapper {
private BluetoothSocket socket;
public NativeBluetoothSocket(BluetoothSocket tmp) {
this.socket = tmp;
}
@Override
public InputStream getInputStream() throws IOException {
return socket.getInputStream();
}
@Override
public OutputStream getOutputStream() throws IOException {
return socket.getOutputStream();
}
@Override
public String getRemoteDeviceName() {
return socket.getRemoteDevice().getName();
}
@Override
public void connect() throws IOException {
socket.connect();
}
@Override
public String getRemoteDeviceAddress() {
return socket.getRemoteDevice().getAddress();
}
@Override
public void close() throws IOException {
socket.close();
}
@Override
public BluetoothSocket getUnderlyingSocket() {
return socket;
}
}
public class FallbackBluetoothSocket extends NativeBluetoothSocket {
private BluetoothSocket fallbackSocket;
public FallbackBluetoothSocket(BluetoothSocket tmp) throws FallbackException {
super(tmp);
try
{
Class<?> clazz = tmp.getRemoteDevice().getClass();
Class<?>[] paramTypes = new Class<?>[] {Integer.TYPE};
Method m = clazz.getMethod("createRfcommSocket", paramTypes);
Object[] params = new Object[] {Integer.valueOf(1)};
fallbackSocket = (BluetoothSocket) m.invoke(tmp.getRemoteDevice(), params);
}
catch (Exception e)
{
throw new FallbackException(e);
}
}
@Override
public InputStream getInputStream() throws IOException {
return fallbackSocket.getInputStream();
}
@Override
public OutputStream getOutputStream() throws IOException {
return fallbackSocket.getOutputStream();
}
@Override
public void connect() throws IOException {
fallbackSocket.connect();
}
@Override
public void close() throws IOException {
fallbackSocket.close();
}
}
public static class FallbackException extends Exception {
/**
*
*/
private static final long serialVersionUID = 1L;
public FallbackException(Exception e) {
super(e);
}
}
public void sendData(BluetoothSocketWrapper socket, int data) throws IOException{
ByteArrayOutputStream output = new ByteArrayOutputStream(4);
output.write(data);
OutputStream outputStream = socket.getOutputStream();
outputStream.write(output.toByteArray());
}
public int receiveData(BluetoothSocketWrapper socket) throws IOException{
byte[] buffer = new byte[256];
ByteArrayInputStream input = new ByteArrayInputStream(buffer);
InputStream inputStream = socket.getInputStream();
inputStream.read(buffer);
return input.read();
}
}
答案 0 :(得分：3)
首先，请停止使用ByteArrayInputStream和ByteArrayOutputStream进行更多控制。
如果套接字发送/接收文本，请执行此操作。
发送：
String text = "My message";
socketOutputStream.write(text.getBytes());
收到：
int length = socketInputStream.read(buffer);
String text = new String(buffer, 0, length);
socketOutputStream应该是您的bluetoothSocket.getOutputStream()。
如果套接字发送/接收大量数据，则键是while循环以防止内存不足异常。当你选择缓冲区大小时，数据将被块读取（例如每4KB缓冲区大小），考虑堆大小，如果你是直播流媒体，也要考虑延迟和质量。
发送：
int length;
while ((length = largeDataInputStream.read(buffer)) != -1) {
socketOutputStream.write(buffer, 0, length);
}
收到：
int length;
//socketInputStream never returns -1 unless connection is broken
while ((length = socketInputStream.read(buffer)) != -1) {
largeDataOutputStream.write(buffer, 0, length);
if (progress >= dataSize) {
break; //Break loop if progress reaches the limit
}
}
<强>常见问题：
largeDataInputStream和largeDataOutputStream？这些流可以是普通的I / O流，FileInputStream / FileOutputStream等。BluetoothSocket的while循环永远不会完成？套接字输入不断接收数据，read()方法阻塞自身直到检测到数据。为了防止阻塞该行中的代码，必须打破while循环。注意：此答案可能需要修改。我不是母语为英语的人。
答案 1 :(得分：1)
根据上述建议，我现在使用此代码检索数据。
public void receiveData(BluetoothSocketWrapper socket) throws IOException{
InputStream socketInputStream = socket.getInputStream();
byte[] buffer = new byte[256];
int bytes;
// Keep looping to listen for received messages
while (true) {
try {
bytes = socketInputStream.read(buffer); //read bytes from input buffer
String readMessage = new String(buffer, 0, bytes);
// Send the obtained bytes to the UI Activity via handler
Log.i("logging", readMessage + "");
} catch (IOException e) {
break;
}
}
}