static L sortedByField(Collection c, final S field) { L l = new ArrayList(c); sort(l, new Comparator() { public int compare(A a, A b) { ret cmp(getOpt(a, field), getOpt(b, field)); } }); ret l; } static L mapMethodLike sortedByField(S field, Collection c) { ret sortedByField(c, field); }