cakebutton.java

Java程序设计(美) David D. Riley著 机械工业出版社 书籍配套 代码

// Figure 9.13

import java.awt.event.ActionEvent;
public class CakeButton extends EventButton  {
	private Driver driver;

	/**	pre:	d != null  <br>
	 *	post:	getX() == x  and  getY() == y
	 *			and  getWidth() == 250  and  getHeight() == 30
	 *			and  getText() == "make and slice a new cake"
	 *			and  driver == d  
	 */
   public CakeButton( int x, int y, Driver d)  {
    	super("make and slice a new cake");
		setBounds(x, y, 250, 30);
        driver = d;
   }

	/** pre:	driver != null  <br>
	 *	note:	the cutTheCake method from driver is performed. 
	 */
	public void actionPerformed( ActionEvent e )   {
        driver.cutTheCake( );
	}
}