/**
* Transmit the specified token to the specified receiver with the specified properties. If
* <i>propagationSpeed</i> is less than Infinity, then this results in a call to fireAt() of the
* director for each receiver that is in range. The token is not actually transmitted to the
* receiver until the corresponding invocation of fire() occurs. The time delay is equal to
* distance/<i>propagationSpeed</i>. See the class comments for the assumptions that make this
* correct.
*
* <p>If the <i>lossProbability</i> is zero, (the default) then the specified receiver will
* receive the token if it has room. If <i>lossProbability</i> is greater than zero, the token
* will be lost with the specified probability, independently for each receiver in range. Note
* that in this base class, a port is in range if it refers to this channel by name and is at the
* right place in the hierarchy. This base class makes no use of the properties argument. But
* derived classes may limit the range or otherwise change transmission properties using this
* argument.
*
* @param token The token to transmit, or null to clear the specified receiver.
* @param sender The sending port.
* @param receiver The receiver to which to transmit.
* @param properties The transmit properties (ignored in this base class).
* @exception IllegalActionException If the token cannot be converted or if the token argument is
* null and the destination receiver does not support clear.
*/
protected void _transmitTo(
Token token, WirelessIOPort sender, WirelessReceiver receiver, RecordToken properties)
throws IllegalActionException {
double speed = ((DoubleToken) propagationSpeed.getToken()).doubleValue();
if (speed == Double.POSITIVE_INFINITY) {
super._transmitTo(token, sender, receiver, properties);
} else {
Director director = getDirector();
// FIXME: This isn't right because the receiver
// may have moved during propagation. Maybe
// register a ValueListener to the _location attributes
// of the receiver actors, and continually recalculate
// the correct arrival time for the message each time the
// receiver location changes. Even so, this will be
// an approximation, and needs to be fully characterized.
// Also, the receiver needs to be in range at the
// conclusion of the propagation, whereas this method is
// called only if the receiver is in range at the
// initiation of the transmission.
WirelessIOPort destination = (WirelessIOPort) receiver.getContainer();
double distance = _distanceBetween(sender, destination);
Time time = director.getModelTime().add(distance / speed);
if (_receptions == null) {
_receptions = new HashMap();
}
Double timeDouble = Double.valueOf(time.getDoubleValue());
Reception reception = new Reception();
reception.token = token;
reception.sender = sender;
reception.receiver = receiver;
reception.properties = properties;
_receptions.put(timeDouble, reception);
_fireAt(time);
}
}
