def self.write_one(object, writer, singular = nil)
singular ||= 'domain'
writer.write_start(singular)
href = object.href
writer.write_attribute('href', href) unless href.nil?
writer.write_attribute('id', object.id) unless object.id.nil?
Writer.write_string(writer, 'comment', object.comment) unless object.comment.nil?
Writer.write_string(writer, 'description', object.description) unless object.description.nil?
Writer.write_string(writer, 'name', object.name) unless object.name.nil?
UserWriter.write_one(object.user, writer, 'user') unless object.user.nil?
GroupWriter.write_many(object.groups, writer, 'group', 'groups') unless object.groups.nil?
UserWriter.write_many(object.users, writer, 'user', 'users') unless object.users.nil?
writer.write_end
end