addAttributeImpl

Expert: Adds a custom AttributeImpl instance with one or more Attribute interfaces.

NOTE: It is not guaranteed, that att is added to the AttributeSource, because the provided attributes may already exist. You should always retrieve the wanted attributes using .getAttribute after adding with this method and cast to your class. The recommended way to use custom implementations is using an [ ].

This method will only add the Attribute interfaces directly implemented by the class and its super classes.