public class BeispielAggregation {

	public static void main(String[] args) {
		Auto a = new Auto(); // Auto bauen
		a.m.start(); // Motor starten
	}

}

class Auto {
	private int name;
	static Motor m;
}

class Motor {
	public static void start() {
		System.out.println("Brumm...");
	}
}