Emmanuel Lecharny wrote:

This is starting to be confusing. The initial question was :

Uh, right... I was halfway answering the question which is too short, halfway Michael.

"Should the toString() method of a class that represents a DN return null or an empty string?"

If a class represents a DN, toString() sounds like it should return that DN's string representation as described in RFC 4514. If you mean to ask what to return when a class instance represents an _empty_ DN, then the string representation is "". toString() not returning a string sounds strange to me whatever the object represents, but maybe that's because I don't know java. But NULL ought to mean "no dn", not "the empty dn".