doorstate.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.
 */

/**
 * This class is the top of a hierarchy of door state classes. The hierarchy is
 * refactored from an earlier version; this version makes door states constant.
 */
public abstract class DoorState implements DoorConstants {
    /**
     * Subclasses must decide what to do when the user clicks 
     * the physical carousel button.
     */
    public abstract void touch(Door door);

    /**
     * By default, discard notifications that the door finished opening or
     * closing.
     */
    public void complete(Door door) {
    }

    /**
     * Return a textual desciption of this state.
     * 
     * @return a textual desciption of this state
     */
    public String status() {
        String s = getClass().getName();
        return s.substring(s.lastIndexOf('.') + 1);
    }

    /**
     * By default, discard notifications that the door began closing after
     * having been open for a while.
     */
    public void timeout(Door door) {
    }
}