Architecture Modeling - SPES 2020

6.1.2 SSemanticss
of obser rvers
This secction
gives aan
overview w of the semmantics
of th he observer automata tthat
are use ed in this
documennt
to specifyy
the formal semantics oof
the pattern ns. These observers
aree
generated from the
patterns and can be used to veri ify that a giveen
compone ent with one input and onne
output sat tisfies the
requiremment.
Figure 1 illustrates the t relationship
between components s and observvers.
For a sinngle
pattern tthere
exist a set of differeent
automata a, depending g on the kind of intervals that t were
used. Thhese
automata
are com mposed withh
other auto omata or ext tended by aadditional
states
and
transitionns
to represeent
complex event expresssions
and conditions. c
The semmantics
are bbased
on HR RC state maachines
[D.2 2.1.c] for the current set of patterns a subset
(Timed AAutomata)
is sufficient. An A intuitive deescription
of the semantic cs is providedd
below.
Basic coomponents
off
automata:
AAutomata
coonsist
of state es and transitions.
SStates
have invariants, which w are nott
shown here e; clock’:=1 is s assumed foor
all clocks)
TTransitions
ccan
be fired if
their guard is true(even nt occurs or variable v is truue)
AActions
can be performed
when transsitions
are fir red
Examplees
of transitioons
with even nts:
• Run: {e} endds
in S1
• Run: {e, e} eends
in S0
Architecture Modeling
Figure 6: CComponent
with w observer
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