door.java

java设计模式源码

package com.oozinoz.carousel2;

/*
 * Copyright (c) 2001, 2005. Steven J. Metsker.
 * 
 * Steve Metsker makes no representations or warranties about
 * the fitness of this software for any particular purpose, 
 * including the implied warranty of merchantability.
 *
 * Please use this software as you wish with the sole
 * restriction that you may not claim that you wrote it.
 */

import java.util.*;

/**
 * This class provides an initial models a carousel door and uses constants for
 * its states.
 */
public class Door extends Observable implements DoorConstants {
    private DoorState state = CLOSED;

    /**
     * The carousel user has clicked the carousel button. This "one touch"
     * button elicits different behaviors, depending on the state of the door.
     */
    public void touch() {
        state.touch(this);
    }

    /**
     * This is a notification from the mechanical carousel that the door
     * finished opening or shutting.
     */
    public void complete() {
        state.complete(this);
    }

    public void setState(DoorState state) {
        this.state = state;
        setChanged();
        notifyObservers();
    }

    /**
     * @return a textual description of the door's state
     */
    public String status() {
        return state.status();
    }

    /**
     * This is a notification from the mechanical carousel that the door got
     * tired of being open.
     */
    public void timeout() {
        state.timeout(this);
    }
}