Emmanuel Lecharny schrieb: > Hi, > > we have many objects that we want to be immutable. What's the best solution > to produce those immutable objets ? > > - For DN, we would like to use valueOf(), and the DN() constructor, but no > setter > - For Entry, a constructor is not enough, as we may have to inject new > attributes. We may need to have two different classes, one immutable, one > mutable. The immutable class could be associated with a factory, or we can > use a constructor with the list of attributes as a parameter. > - For attributes, we have the same problem : we may have more than one > value. > > DO any of you guys have a strong opinion ?
Entry and Attribute object created by the user of the API shouldn't be immutable. As user of the API I want to create an Entry object and add attribute and values to it. So the API must provide setters. So I think if Entry and Attribute are interfaces we just define the getter methods. The default implementations of those classes (e.g. ClientEntry and ClientAttribute) additional have setters the user can use when constructing the objects. The Entry objects returned from the API (e.g. from a search) should be immutable to protect them from being casted by the user, e.g. by wrapping a created ClientEntry into an ImmutableEntry implementation. Kind Regards, Stefan