The short story

The "mobility simulation", or short "mobsim", is what executes all selected plans, and writes events.

The slightly longer story

You can do

Controler controler = new Controler() ;
controler.setMobsimFactory( new MyMobsimFactory() ) ;

plus

public class MyMobsimFactory implements MobsimFactory {
    public Simulation createMobsim( Scenario sc, EventsManager ev ) {
        return new MyMobsim( sc, ev ) ;
    }
}

plus

class MyMobsim extends Simulation {
    Scenario sc ; EventsManager ev ;
    MyMobsim( Scenario sc , EventsManger ev ) {
        this.sc = sc ; this.ev = ev ;
    }
    public void run() {
        Network net = sc.getNetwork() ;
        Population pop = sc.getPopulation() ;
        ...
        EventsFactory ef = ev.getFactory() ;
        ev.processEvent( ef.createXXXEvent( ... ) ) ;
        ...
    }
}

This is fully api-based (except that some material is still under core.api.experimental) .

You then need to make sure that

• you execute all selected plans
• you generate agent activity end events
• you generate agent/vehicle departure events
• you generate link leave events
• you generate link enter events
• you generate agent/vehicle arrival events
• you generate agent activity start events

If you do this, your mobsim should work inside the MATSim iterative framework.