Untitled

synchronized methods in a Runnable
public class Packer implements Runnable {
    private BlockingQueue<byte[]> msgQueue;
    private Object lock = new Object();
    private Packet packet;
    private boolean running = false;

    public synchronized void append(byte[] payload) throws InterruptedException {
        msgQueue.put(payload);
    }

    public synchronized void setPacketCapacity(int size) {
        synchronized (lock) {
            // check to see if we need to flush the current packet first, etc.
            packet.setCapacity(size);
        }
    }
    public void run() {
        running = true;
        while (running) {
            try {
                byte[] msg = msgQueue.take();
                synchronized (lock) {
                    packet.add(msg);
                    // check if we need to flush the packet, etc.
                }
            } catch (InterruptedException ex) {
                logger.warn("interrupted");
                running = false;
            } catch (Exception e) {
                logger.error(e);
            }
        }
        logger.warn("stop");
    }
}