Java – Why is my PipedOutputStream deadlock?

I’m trying to implement a thread-loop buffer using PipedInputStream and PipedOutputStream, but it locks every time I go into mHead.write in Decoder runnable. I don’t think there will be deadlocks when using separate threads.

    private class DecoderTask implements Runnable{

@Override
    public void run() {
        while(!mStop){
            try {
                    Log.d(TAG,"trying to write");
        mHead.write(decode( 0, 1000));
            mHead.flush();
            Log.d(TAG,"Decoded");
            } catch (DecoderException e) {
                Log.e(TAG,e.toString());
            } catch (IOException e) {
                Log.e(TAG,e.toString());
            }
        }
    }

}
private class WriteTask implements Runnable{

@Override
    public void run() {
        while(!mStop){
            try {
                                 Log.d(TAG,"trying to read");
                 int read = mTail.read(mByteSlave, 0, mByteSlave.length);
                 mAudioTrack.flush();
                                 mAudioTrack.write(mByteSlave,0,read);
                                 Log.d(TAG,"read");                 
            } catch (IOException e) {
                Log.e(TAG,e.toString());
            }
        }
    }

}

in some function
mTail = new PipedInputStream();
mHead = new PipedOutputStream(mTail);
mByteSlave = new byte[BUF];
mT1 = new Thread(new DecoderTask(), "Reader");
mT2 = new Thread(new WriteTask(), "Writer");
mT1.start();
mT2.start();
return;

EDIT: This is the full source of my service http://pastie.org/1179792

logcat prints out:

Try reading
Make an effort to write

I’ve had the same issue and solved the PIPE_SIZE by overriding the default In PipedInputStream( int) constructor. Method PipedOutputStream.write(byte[], int, int) blocks until all bytes are written to the output stream. This may be an issue with the default PIPE_SIZE.

After all, size matters 😉