code: @Override
      int write_attribute_asynch_i(final DeviceAttribute da, final boolean fwd, final int rid) throws DevFailed {
  	try {
  	    final int actual_rid = proxy.write_attribute_asynch(da);
  	    arp.put(new Integer(rid), new AsynchRequest(actual_rid, da.getName()));
  	} catch (final DevFailed df) {
  	    arp.put(new Integer(rid), new AsynchRequest(-1, da.getName(), df));
  	} catch (final Exception e) {
  	    final DevError[] errors = new DevError[1];
  	    errors[0] = new DevError();
  	    errors[0].severity = ErrSeverity.ERR;
  	    errors[0].reason = "unknown exception caught";
  	    errors[0].desc = "unknown error";
  	    errors[0].origin = "GroupDeviceElemnt.write_attribute";
  	    final DevFailed ex = new DevFailed(errors);
  	    arp.put(new Integer(rid), new AsynchRequest(-1, da.getName(), ex));
  	}
  	return rid;
      }
docs: read_attribute_asynch_i - access limited to package Group