void close() { // closing watch dog if (conCheckWatchDogTask != null) { conCheckWatchDogTask.cancel(); conCheckWatchDogTask = null; } // close open connections try { for (NonBlockingConnection connection : getConnections()) { try { connection.close(); } catch (IOException ioe) { if (LOG.isLoggable(Level.FINE)) { LOG.fine( "error occured by closing connection " + connection.getId() + " " + DataConverter.toString(ioe)); } } } } catch (Throwable e) { if (LOG.isLoggable(Level.FINE)) { LOG.fine("error occured by closing open connections " + DataConverter.toString(e)); } } // clear handle list handles.clear(); }