Property :: active - Is property an active property

An active property is a property that is able to react on events. Active properties are treated in a special way since events are generated for several occasions.

A property handle is considered as active, when the property or extent definition refers to a resource, i.e. when it has got a resource id. This is necessary, but not sufficient, since the resource id provides the link to a context class, which implements property behavior. The property is, however, considered as active also, when no context class is linked with the resource.

The property throws an exception, when the property handle is not valid.