Information Technology Reference
In-Depth Information
provided by static schemata, which in UML are expressed by means of object
diagrams.
For instance, the UML package shown in figure 3.4 expresses a possible
state of one repair order, in which the order has been registered, the telephone
tested and found faulty, and a loan handset has been assigned and given to the
user. No further actions have been done for that order so far | for example,
the faulty handset has not yet been sent to the manufacturer for repair.
3.4
Structure of the Information Specification
All the elements that constitute the information specification of the system
are gathered together within a single model, stereotyped
«
Information Spec
»
.
This model contains the set of packages that express the invariant, static
and dynamic schemata of the information specification, structuring them
in different packages for organizational purposes.
Figure 3.5 depicts the
«
Information Spec
»
model for the PhoneMob system.
«Information_Spec»
PhoneMob (I_Spec)
InvariantSchemata
StaticSchemata
«IV_InvariantSchema»
InformationObjectTypes
«IV_StaticSchema»
InitialSystemState
{locationInTime = "2010−06−01,
10:00 UTC" }
«IV_InvariantSchema»
InformationActionTypes
«IV_StaticSchema»
PendingOrderExample
{locationInTime = "2010−07−01,
12:00 UTC" }
FIGURE 3.5: Structure of the PhoneMob information specification.
Note that in this figure there is no package for the specification of dynamic
schemata. Given that they are modelled in UML as state machines associ-
ated with the corresponding object types, splitting their specification across
different packages does not make much sense.
