Interface VoidClass

All Superinterfaces:
DataClass, PropertyHandler
All Known Implementing Classes:

public interface VoidClass extends DataClass
The Void Class defines unspecified values.

In some situations it is important to know why an value is not defined. Therefore, it is possible to define different kind of void. For example, a aggregate query consists in general of attributes for that values are defined and of attributes without defined values. Attributes with undefined values contain instances of the Void class. With sub classes of void it is possible to specify why an attribute is not defined.

Rainer Maximini