Behavioral -- Mediator

--- Mediator.java ---

package behavioral.mediator;

public interface Mediator {

void changed(Colleague colleague);

}

--- ConcreteMediator.java ---

package behavioral.mediator;

public class ConcreteMediator implements Mediator {

private ConcreteColleague aConcreteColleague;

public void changed(Colleague colleague) {

}

public void setConcreteColleague(ConcreteColleague colleague) {
aConcreteColleague = colleague;
}

}

--- Colleague.java ---

package behavioral.mediator;

public abstract class Colleague {

private Mediator theMediator;

public Colleague(Mediator aMediator) {
theMediator = aMediator;
}

protected Mediator getMediator() {
return theMediator;
}

}

--- ConcreteColleague.java ---

package behavioral.mediator;

public class ConcreteColleague extends Colleague {

public ConcreteColleague(Mediator aMediator) {
super(aMediator);
}

public void sampleOperation() {
getMediator().changed(this);
}

}