package ca.ubc.cs.spl.aspectPatterns.examples.chainOfResponsibility.java;
/* -*- Mode: Java; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This file is part of the design patterns project at UBC
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* either http://www.mozilla.org/MPL/ or http://aspectj.org/MPL/.
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is ca.ubc.cs.spl.aspectPatterns.
*
* For more details and the latest version of this code, please see:
* http://www.cs.ubc.ca/labs/spl/projects/aodps.html
*
* Contributor(s):
*/
import javax.swing.JFrame;
import java.awt.event.WindowEvent;
import java.awt.event.WindowAdapter;
/**
* Represents a regular GUI frame modified to play its role in the
* <i>Chain of Responisiblity</i> pattern, i.e. to handle requests and/or
* forward them to its successor in the chain.
*
* Requests are only handled if the ALT key is pressed during a click.
*
* @author Jan Hannemann
* @author Gregor Kiczales
* @version 1.1, 01/27/04
*
*/
public class Frame extends JFrame implements ClickHandler {
/**
* the successor in the chain of responsibility
*/
protected ClickHandler successor;
/**
* Creates a <code>Frame</code> with a given title that responds
* properly to <code>WindowClosing<code> events. The frame
* does not have a successor and handles request that it receives.
*
* @param title the frame title
*/
public Frame(String title) {
super(title);
this.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
}
/**
* Implements the method to handle requests as defined by the
* <code>ClickHandler</code> interface. The request is only handled here
* if the ALT key was pressed.
*
* @see ClickHandler
*/
public void handleClick(Click click) {
System.out.println("Frame is asked to handle the request...");
if (click.hasAltMask()) {
System.out.println("Frame handles the request.");
} else {
if (successor == null) {
throw new RuntimeException("request unhandled (end of chain reached)");
} else {
successor.handleClick(click);
}
}
}
}