[sumo-user] libsumo returning 0, empty lists for vehicle queries

["Nine, Harmon S" <harmon.s.nine@xxxxxxxxxxxxxx>]

Hello.

I have a java program (shown below).  I can load and step through the model, and it even warns that some vehicles have to perform emergency braking.

However, vehicle queries like "Simulation.getLoadedNumber()" are returning 0 when this clearly should not be.

Anyone know what's wrong?  I'm using sumo-1.8.0.

=========================

package sumotest;

import org.eclipse.sumo.libsumo.Simulation;
import org.eclipse.sumo.libsumo.StringVector;


public class App {

    public static void main(String[] args) {
        System.loadLibrary("libsumojni");
        Simulation.load(new StringVector(new String[] {"-c", "SUMO/subway.sumo.cfg"}));
        Simulation.subscribe();
        for(int ix = 0 ; ix < 50000 ; ++ix) {
            Simulation.step();
        }
        System.out.println("Loaded vehicles: " + Simulation.getLoadedNumber()); // prints "0"
        Simulation.close();
    }
}

==========================

-- Harmon