String menuIds = "1,2,3,4,5,6";

List<String> inputMenuIds = Arrays.asList(menuIds.split(","));

List<Integer> menuIdList = new ArrayList<Integer>();

CollectionUtils.collect(inputMenuIds, new Transformer() {
   @Override
public Object transform(Object o) {
      return Integer.valueOf
 
(o.toString());
   }
}, menuIdList);

用到的包 

org.apache.commons.collections.CollectionUtils;