/** * Returns a set of the members of this directory or {@code null} if and * only if there is no directory archive entry mapped. * This is a bidirectional view: Any change is reflected in the set and * vice versa. */ @Override public @Nullable Set<String> getMembers() { if (!isType(DIRECTORY)) return members = null; final Set<String> m = members; return null != m ? m : (members = new LinkedHashSet<>()); }