SEKE 2012 Proceedings - Knowledge Systems Institute

example, (Circle, t 5 , t 6 , x 4 ,). When an InternalTransition is
executed in a Mo de, an ExitStep whose targe is the starting
pseudostate of the InternalTransition and an EntryStep
originating from the target pseudostate of the Internal-
Transition will take place meanwhile, forming an execution
path called InternalStep, for example, (free, t 2 , t 3 , t 4 , Circle).
When a top-level Mode resides in a certain StateConfiguration,
continuous variables will be updated according to the flow and
invariant constraints contained in the StateConfiguration, and
such an execution process is called a ContinuousStep, As
shown in F igure 2, (DATC:free, DATC.flows∩free.flows,
DATC.invs∩free.invs) is a ContinuousStep.
B. Metamodel of QHP model
top-level Mode m, the execution process of the rule
TLMode2QHPCode is as follows. First, get all EntryStep
instances of m by calling ATL helper EntrySteps, and by rule
ES2QHPI, each EntryStep is mapped to a QHPInitialization
instance, making up IBS. Second, get all InternalStep instances
of m by calling helper InternalSteps, and by rule IS2QHPDT,
each InternalStep is mapped to a QHPDTransition instance
composing DTS. Third, get all ContinusStep instances of m by
calling helper ContinusSteps, and by rule CS2QHPCT, each
ContinusStep is mapped to a QHPCTransition instance
composing CTS. Fourth, get the mark indicating whether all
InternalStep instances composes an execution cycle by calling
helper CycleSymbol, and as a Boolean variable, CycleSymbol
can be assigned directly to the variable Cycle of the QHP
model p. Finally, template rule QHPModel2QHPCode will be
invoked to generate final QHP code form QHP model p.
2) QHP code generation from QHP model
TABLE II.
MAIN TEMPLATE RULE
Figure 3. Metamodel of QHP model
Definition 2. (QHP) A QHP model can be formalized as a
tuple: , where
IBS, DTS and CTS denote the set of all QHPInitialization,
QHPDTransition and QHPCTransition instances of the QHP
model respectively, Cycle signifies whether the model can be
executed repeatedly, and SG denotes all QHPState instances.
As for other model element, see Figure 3.
C. Model transformation from toplevel Mode to QHP Code
1) Description of main transformation rule based on ATL
TABLE I. MAIN TRANSFORMATION RULE-TLMODE2QHPCODE
entrypoint rule TLMode2QHPCode{
from
m:Mode(m.isTopLevelMode=true)
to
p:QHP (
IBScollect(i|thisModule.ES2QHPI(i)),
DTScollect(d|thisModule.IS2QHPDT(d)),
CTScollect(i|thisModule.CS2QHPCT(i)),
Cycle