Implement A Timeout In Bluetoothsocket Inputstream.read() In Android

Is it possible to implement a timeout in an inputstream.read() function from a BluetoothSocket in Android? I've tried using Thread.sleep() but this only pauses my activity. ---Upda

Solution 1:

You could do something like this:

InputStream in = someBluetoothSocket.getInputStream();
int timeout = 0;
int maxTimeout = 8; // leads to a timeout of 2 secondsint available = 0;

while((available = in.available()) == 0 && timeout < maxTimeout) {
    timeout++;
    // throws interrupted exception
    Thread.sleep(250);
}

byte[] read = newbyte[available];
in.read(read);

This way you are able to initially read from a stream with a specific timeout. If u want to implement a timeout at any time of reading you can try something like this:

ThreadreadThread=newReadThread(); // being a thread you use to read from an InputStreamtry {
   synchronized (readThread) {
      // edit: start readThread here
      readThread.start();
      readThread.wait(timeOutInMilliSeconds);
   }
catch (InterruptedException e) {}

using this you may need some kind of event handler to notify your application if the thread actually read something from the input stream.

I hope that helps!

----edit:

I implemented an example without using any handlers.

Sockets=newSocket("localhost", 8080);
    finalInputStreamin= s.getInputStream();

    ThreadreadThread=newThread(newRunnable() {
        publicvoidrun() {
            intread=0;
            try {
                while((read = in.read()) >= 0) {
                    System.out.println(newString(newbyte[]{ (byte) read }));
                }
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    });

    synchronized (readThread) {
        readThread.start();
        try {
            readThread.wait(2000);

            if(readThread.isAlive()) {
                                    // probably really not good practice!
                in.close();
                System.out.println("Timeout exceeded!");
            }
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

Solution 2:

A Kotlin extension function for socket read with timeout:

fun InputStream.read(
  buffer: ByteArray,
  offset: Int,
  length: Int,
  timeout: Long
): Int = runBlocking {
    val readAsync = async {
        if (available() > 0) read(buffer, offset, length) else0
    }
    var byteCount = 0var retries = 3while (byteCount == 0 && retries > 0) {
        withTimeout(timeout) {
            byteCount = readAsync.await()
        }
        delay(timeout)
        retries--
    }
    byteCount
}