boolean function ( ) { return ( fileDescriptor >= 0 ) ; }
this method is called to determine if the serial port is already open . concode_field_sep int monitorInterval concode_elem_sep int fileDescriptor concode_elem_sep SerialDataMonitorThread monitor concode_elem_sep CopyOnWriteArrayList<SerialDataListener> listeners concode_elem_sep boolean isshutdown concode_field_sep char read concode_elem_sep int getMonitorInterval concode_elem_sep void writeln concode_elem_sep void writeln concode_elem_sep void removeListener concode_elem_sep boolean isClosed concode_elem_sep void flush concode_elem_sep void setMonitorInterval concode_elem_sep void close concode_elem_sep void write concode_elem_sep void write concode_elem_sep void write concode_elem_sep void write concode_elem_sep void write concode_elem_sep void write concode_elem_sep void open concode_elem_sep void shutdown concode_elem_sep int availableBytes concode_elem_sep void addListener concode_elem_sep boolean isShutdown