code: @Override
  	public Collection<BioPAXElement> generate(Match match, int ... ind)
  	{
  		BioPAXElement ele0 = match.get(ind[0]);
  
  		if (ele0 == null)
  			throw new RuntimeException("Constraint cannot generate based on null value");
  
  		Set vals = pa.getValueFromBean(ele0);
  		List<BioPAXElement> list = new ArrayList<BioPAXElement>(vals.size());
  
  		for (Object o : vals)
  		{
  			assert o instanceof BioPAXElement;
  			list.add((BioPAXElement) o);
  		}
  		return list;
  	}
docs: Uses the encapsulated PAthAccessor to generate satisfying elements.
  @param match current pattern match
  @param ind mapped indices
  @return generated elements