code: public void add(final String p) throws DevFailed {
  	synchronized (this) {
  
  	    final Vector v = factory.instanciate(p);
  	    final Iterator it = v.iterator();
  	    while (it.hasNext()) {
  		add_i((GroupElement) it.next());
  	    }
  
  	}
      }
docs: Adds devices matching pattern
  <p>
  to the group
  
  @throws DevFailed