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property instance

A property instance is an instantiation of a property in a complex instance or object space. Property instances consist of any number of complex or elementary data type instances. The property value is defined by the set of instances belonging to the property, but not by the value of these instances.

Usually, complex instances of a property have the same complex data type. In general, however, complex instances belonging to a property may have different types (weak-typed or untyped collections).

Instances of a property may be owned by the property or not. All instances belonging to an owning property have the same persistence type (persistence type of the property). When not owning the instances, allowed persistence types for instances belonging to the property instance depend on the persistence type of the property:


property \ instance

persistent

perm temp

bound temp

perm trans

bound trans

persistent

X/O

-

-

-

-

perm temp

X

X/O

-

-

-

bound temp

X

X

X/O

-

-

perm trans

X

X

X

X/O

-

bound trans

X

X

X

X

X/O

O - persistence type supported for owning properties

X - persistence type supported for not owning properties


Generalisations:  instance
Specialisations:  collection instancearray instance