/**
* Wait for value of device to reach the desired value (within tolerance)
*
* @throws TimeoutException on timeout
* @throws Exception on interruption or device read error
*/
@Override
public void await() throws TimeoutException, Exception {
final WaitWithTimeout timeout = new WaitWithTimeout(this.timeout);
// Fetch initial value with get-callback
initial_value = VTypeHelper.toDouble(device.read(value_check_timeout));
device.addListener(this);
try {
// Synchronize to avoid the following situation:
// 1. not at desired value
// 2. device changes and we would be notified
// 3. ... but that's before we call wait, so we wait forever
synchronized (this) {
is_condition_met = isConditionMet();
while (!is_condition_met) { // Wait for update from device
if (timeout.waitUntilTimeout(this))
throw new TimeoutException(
"Timeout while waiting for " + device + " " + comparison + " " + desired_value);
if (error != null) throw error;
}
}
} finally {
device.removeListener(this);
}
}
/** Trigger another check of device's value {@inheritDoc} */
@Override
public void deviceChanged(final Device device) {
synchronized (this) {
try {
if (Double.isNaN(initial_value)) initial_value = VTypeHelper.toDouble(device.read());
is_condition_met = isConditionMet();
} catch (Exception ex) {
is_condition_met = false;
error = ex;
}
// Notify await() so it can check again.
notifyAll();
}
}
/**
* Simulate one step in the loop iteration
*
* @param context {@link SimulationContext}
* @param device {@link SimulatedDevice} that the loop modifies
* @param value Value of the loop variable for this iteration
* @throws Exception on error
*/
private void simulateStep(
final SimulationContext context, final SimulatedDevice device, final double value)
throws Exception {
// Get previous value
final double original = VTypeHelper.toDouble(device.read());
// Estimate execution time
final double time_estimate = command.getWait() ? device.getChangeTimeEstimate(value) : 0.0;
// Show command
final StringBuilder buf = new StringBuilder();
buf.append("Loop '").append(command.getDeviceName()).append("' = ").append(value);
command.appendConditionDetail(buf);
if (!Double.isNaN(original)) buf.append(" [was ").append(original).append("]");
context.logExecutionStep(context.getMacros().resolveMacros(buf.toString()), time_estimate);
// Set to (simulated) new value
device.write(value);
// Simulate loop body
context.simulate(implementation);
}
/**
* Determine if the condition is currently met
*
* @return <code>true</code> if condition is met
* @throws Exception on error reading from the device
*/
public boolean isConditionMet() throws Exception {
final double value = VTypeHelper.toDouble(device.read());
// Note that these need to fail "safe" if any of the values are NaN
switch (comparison) {
case EQUALS:
return Math.abs(desired_value - value) <= tolerance;
case AT_LEAST:
return value >= desired_value;
case ABOVE:
return value > desired_value;
case AT_MOST:
return value <= desired_value;
case BELOW:
return value < desired_value;
case INCREASE_BY:
return value >= initial_value + desired_value;
case DECREASE_BY:
return value <= initial_value - desired_value;
default:
throw new Error("Condition not implemented: " + comparison);
}
}
