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Classifier (from Kernel , Dependencies , PowerTypes ) on page 51
Issue 8508 -fix capitalization and some typos and clarifications
An information item is an abstraction of all kinds of information that can be exchanged between objects. It is a kind of classifier
intended for representing information at a very abstract way, one which cannot be instantiated.
One purpose of information items is to be able to define preliminary models, before having made detailed modeling decisions
on types or structures. One other purpose of information items and information flows is to abstract complex models by a less
precise but more general representation of the information exchanged between entities of a system.
Attributes No additional attributes
Associations • represented : Classifier [*]
|Determines the classifiers that will specify the structure and nature of the information. An information item represents all its represented classifiers.|
Issue 8506 -add OCL expressions
 The sources and targets of an information item (its related information flows) must designate subsets of the sources
and targets of the representation information item, if any. The Classifiers that can realize an information item can only
be of the following kind: Class, Interface, InformationItem, Signal, Component.
(self.represented.select(p | p->oclIsKindOf(InformationItem))->forAll(p | p.informationFlow.source->forAll( q | self.informationFlow.source->include(q) ) and p.informationFlow.target->forAll( q |self.informationFlow.target->include(q) ) ))
(self.represented->forAll(p |p->oclIsKindOf(Class) or oclIsKindOf(Interface) or oclIsKindOf(InformationItem) or oclIsKindOf(Signal) or oclIsKindOf(Component)))
 An information item has no feature, no generalization, and no associations.
self.generalization->isEmpty() and self.feature->isEmpty()
 It is not instantiable.
Information as represented by an information item encompasses all sorts of data, events, facts that are exploited inside the
modeled system. For example, the information item wage can represent a Salary Class, or a Bonus Class (see example
). An information item does not specify the structure, the type, or the nature of the represented information. It specifies
at an abstract level the elements of information that will be exchanged inside a system. More accurate description will be
provided by defining the classifiers represented by information item.
Issue 8508 - fix capitalization and typos
Information items can be decomposed into more specific information items using representation links between them. This gives
the ability to express that in specific contexts (specific information flows) a specific information is exchanged.
Information items cannot have properties, or associations. Specifying this detailed information belongs to the represented
Being a classifier, an information item can be represented as a name inside a rectangle. The keyword «information» or the
black triangle icon on top of this rectangle indicates that it is an information item.
Figure 17.4 - Information Item represented as a classifier
Representation links between a classifier and a representation item are represented as dashed lines with the keyword «representation».
An information item is usually represented attached to an information flow, or to a relationship realizing an information
flow. When it is attached to an information flow (see Figure 17.3) its name is displayed close to the information flow line.
When it is attached to an information channel, a black triangle on the information channel indicates the direction (source
and target) of the realized information flow conveying the information item, and its name is displayed close to that
triangle. In the example Figure 17.7, two associations are realizing information flows. The black triangle indicates that
information flow is realized, and the information item name is displayed close to the triangle.
The example Figure 17.6 shows the case of information items represented on connectors. When several information items
having the same direction are represented, only one triangle is shown, and the list of information item names, separated by
a comma is presented.
The name of the information item can be prefixed by the names of the container elements, such as a container information flow,
or a container package or classifier, separated by a colon.
Figure 17.6 - Information item attached to connectors
Figure 17.7 - Information Items attached to associations