code: public WatchObject watch(final boolean enable, final boolean dumpData, final String device) throws IOException, JSONException {
  		JSONObject watch = new JSONObject();
  		watch.put("class", "WATCH");
  		watch.put("enable", enable);
  		watch.put("json", dumpData);
  		if (device != null) {
  			watch.put("device", device);
  		}
  		return this.syncCommand("?WATCH=" + watch.toString(), WatchObject.class);
  	}
docs: send WATCH command
  
  @param enable   enable/disable watch mode
  @param dumpData enable/disable dumping of data
  @param device   If present, enable watching only of the specified device rather than all devices
  @return {@link WatchObject}
  @throws IOException   on IO error in socket
  @throws JSONException