Hands-On Design Patterns with Java

Hopper

The Hopper class contains two class variables, a constructor method and an accessor method, to determine whether the hopper is currently enabled. The class code is as follows:

public class Hopper {    private WidgetProductionSystem mediator;    private boolean enabled;    // constructor    public Hopper(WidgetProductionSystem mediator) {        this.mediator = mediator;        enabled = false;        mediator.mediateHopper(this);    }    // accessor    public boolean getHopperEnabled() {        return enabled;    }    public void enable() {        enabled = true;        mediator.hopperEnabled();        System.out.println("Mediated Event: Hopper Initialized.");    }    public void disable() {        enabled = false;        mediator.hopperDisabled();        System.out.println("Mediated Event: Hopper Deinitialized.");    }}

The final two ...