to_jsonable in java

	static public Object to_jsonnable(Object o) {
	  if (o instanceof List) { 
		List lo = (List)o;
		ArrayList nlo = new ArrayList();
		for (Object a : lo) nlo.add(to_jsonnable(a)) ;
		return(nlo);
	  } else if (o instanceof Map) {
			Map mo = (Map)o;
			LinkedHashMap<Object, Object> nmo =
                            new LinkedHashMap<Object, Object>();
			for (Object a : mo.entrySet() ) {
				Map.Entry me = (Map.Entry)a;
				nmo.put(me.getKey().toString(),to_jsonnable(me.getValue()));
			}
			return(nmo);
	  } else if (o instanceof RubyNumeric) 
		 return(o) ;
	  else
		  return(o.toString());
	}