Architecture Modeling - SPES 2020

Constrrain
Eventts
with Intervals
It is not always wanted
to react on every occcurrence
of f an event. Constraining
C
an event through
an
interval is
a natural wway
of filterin ng events. Thhis
can be ac chieved by th he following nnotation:
Event durring
[inte erval]
An exammple
shall demonstrate
th he use of thiss
language construct
A responsee
to a request
shall only bbe
send if the e system got activated through
a mes ssage.
This behavior
can be fo ormalized to:
whenever
occurs.
request t during
Architecture Modeling
[activa ate,deacti ivate] ooccurs
re esponse
There are eevents
that indicate
the aactivation
an nd the deactivation
of thee
system/component.
Only the requests
that occur o duringg
the specifie ed interval will
trigger thiss
pattern. The
interval
acts like a filter on the event. For mmore
informa ation on inter rvals see secction
6.1.1.1.1.2.
It is
also possibble
to use the e different kinnd
of bracket ts here for th he interval ass
described in
section
0. Further the
usage of real times (liike
5 ms) is allowed a in the
intervals.
The patternn
above typic cally needs a refinement, , since the sp pecification oof
the respon nse event
lacks an intterval
where it should occcur.
The bassic
block for building eve ent expressioon
with “during”
is shown
below. Forr
a description
of the
construcction
of open and closed intervals fromm
this basic block refer to o section 0.
Complexx
expressionn
can be buil lt by nestingg
of multiple during expre essions. For each nestin ng level a
basic block
is instaantiated
that sends a teemporary
ev vent to the higher levell.
Depending g on the
integratioon
in the oveerall
context, , the states “ “0” and “1” are a merged in nto the “pre” ” state resulting
in the
“out” state
to ensure correct beha avior when mmultiple
instances
of the event e occur.
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