@Override
        public boolean available() throws GuacamoleException {
            return !instructionQueue.isEmpty() || getDelegateSocket().getReader().available();
        }
GuacamoleReader which reads instructions from the queue populated when
the FailoverGuacamoleSocket was constructed. Once the queue has been
emptied, reads are delegated directly to the reader of the wrapped
socket.
guacamole-common/src/main/java/org/apache/guacamole/protocol/FailoverGuacamoleSocket.java