A simple
EntitySystemthat processes a Family of entities not once per frame, but after a given interval. Entity processing logic should be placed inprocessEntity(Entity). For more info, please see IntervalIteratingSystem
In the below code example, the best usage for this is the physics world step.
public class Constants {
     public final static float TIME_STEP = 1 / 60.0f; // 60 fps
     public final static int VELOCITY_ITERATIONS = 6;
     public final static int POSITION_ITERATIONS = 2;
}
public class PhysicsSystem extends IntervalIteratingSystem {
    public PhysicsSystem () {
         super(Family.all(PhysicsComponent.class), Constants.TIME_STEP);
    }
    @Override
    protected void processEntity(Entity entity) {
         // process the physics component here with an interval of 60fps
    }
    @Override
    protected void updateInterval() {
        WorldManager.world.step(Constants.TIME_STEP, Constants.VELOCITY_ITERATIONS, Constants.POSITION_ITERATIONS);
        super.updateInterval();
    }
}