PTOLEMY II - CiteSeerX

public class Average extends Transformer {
}
... constructor ...
///////////////////////////////////////////////////////////////////
//// ports and parameters ////
public TypedIOPort reset;
///////////////////////////////////////////////////////////////////
//// public methods ////
... clone method ...
public void fire() throws IllegalActionException {
_latestSum = _sum;
_latestCount = _count + 1;
// Check whether to reset.
for (int i = 0; i < reset.getWidth(); i++) {
if (reset.hasToken(i)) {
BooleanToken r = (BooleanToken)reset.get(0);
if b(r.booleanValue()) {
// Being reset at this firing.
_latestSum = null;
_latestCount = 1;
}
}
}
if (input.hasToken(0)) {
Token in = input.get(0);
if (_latestSum == null) {
_latestSum = in;
} else {
_latestSum = _latestSum.add(in);
}
Token out = _latestSum.divide(new IntToken(_latestCount));
output.send(0, out);
}
}
public void initialize() throws IllegalActionException {
super.initialize();
_count = 0;
_sum = null;
}
public boolean postfire() throws IllegalActionException {
_sum = _latestSum;
_count = _latestCount;
return super.postfire();
}
///////////////////////////////////////////////////////////////////
//// private members ////
private Token _sum;
private Token _latestSum;
private int _count = 0;
private int _latestCount;
FIGURE 5.8. Code segment from the Average actor, showing the action methods.
Designing Actors
166 Ptolemy II