simenvelopeacceptor.java

来自「含有uml的多个实例及实例的java源码。」· Java 代码 · 共 113 行

/*
 * ATM Example system - file SimEnvelopeAcceptor.java
 *
 * copyright (c) 2001 - Russell C. Bjork
 *
 */
 
package simulation;

import java.awt.*;
import java.awt.event.*;

/** Simulate the envelope acceptor
 */
class SimEnvelopeAcceptor extends Button
{
    /** Constructor
     */
    SimEnvelopeAcceptor()
    {
        super("Click to insert envelope");
        addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e)
            {
                synchronized(SimEnvelopeAcceptor.this)
                {
                    inserted = true;
                    SimEnvelopeAcceptor.this.notify();
                }
            }
        });
    }
    
    /** Simulate accepting an envelope from customer.
     *
     *  return true if an envelope was received within the prescribed time,
     *         else false
     */
    public synchronized boolean acceptEnvelope()
    {
        inserted = false;
        setVisible(true);
            
        // Wait for user to simulate inserting envelope by clicking button.
        // If we wait 20 seconds and no envelope is entered, we time out

        try
        { 
            wait(MAXIMUM_WAIT_TIME);
        }
        catch(InterruptedException e)
        { }
        
        if (inserted)
        {
            // Animate envelope going into the machine
            
            Rectangle originalBounds = getBounds();
            
            Rectangle currentBounds =
               new Rectangle(originalBounds.x, originalBounds.y,
                             originalBounds.width, originalBounds.height);
                             
            while (currentBounds.width > 0 && currentBounds.height > 0)
            { 
                setBounds(currentBounds.x, currentBounds.y,
                        currentBounds.width, currentBounds.height);
                repaint();
                try 
                { 
                    Thread.sleep(100);
                } 
                catch (InterruptedException e) 
                { }
                currentBounds.height -= 1;
                currentBounds.width = 
                  (originalBounds.width * currentBounds.height) / originalBounds.height;
                currentBounds.x =
                  originalBounds.x + (originalBounds.width - currentBounds.width) / 2;
                currentBounds.y =
                  originalBounds.y + (originalBounds.height - currentBounds.height) / 2;
            }
            
            setVisible(false);
            setBounds(originalBounds);
        }
        else
        {
            setVisible(false);
        }
        return inserted;
    }

    /** Inform the envelope acceptor that the customer has pressed the CANCEL
     *  key.  Ignored if not waiting for an envelope
     */
    public synchronized void cancelRequested()
    {
        notify();       // End the wait for the envelope - inserted will still
                        // be false so acceptEnvelope() will return false
    }
    
    /** Becomes true when an envelope has been inserted
     */
    private boolean inserted;
    
    /** Maximum time to wait for an envelope before timing out - in milliseconds
     */
    private static long MAXIMUM_WAIT_TIME = 20 * 1000;
}