/*
 * ButtonObj Class
 *
 * Developed for "Rethinking CS101", a project of Lynn Andrea Stein's AP Group.
 * For more information, see <a href="http://www.ai.mit.edu/projects/cs101/">the
 * CS101 homepage</a> or email <las@ai.mit.edu>.
 *
 * Copyright (C) 1997 Massachusetts Institute of Technology.
 * Please do not redistribute without obtaining permission.
 */
package Calculator;

/**
 * An instance of this class is a smart button object that knows how
 * to handle itself.  There should be one for each button on the
 * Calculator.  The ButtonHandler will activate each ButtonObj as its
 * button is pressed. <p>
 *
 * This class is a pretty generic button handler; it doesn't do
 * anything.  Its subclasses should override handleButton() to make it
 * do something interesting.  The fields of this class are protected
 * (rather than private) precisely to allow access in these overridden
 * methods.<p>
 *
 * Each ButtonObj knows about the Calculator (or at any rate a text
 * interface to the Calculator) and its state.  <p>
 *
 * It might be reasonable to declare this class abstract.
 *
 * @author:  Lynn Andrea Stein, las@ai.mit.edu
 * @version: $$
 * @see Calculator, CalcTextGUI, CalculatorState, ButtonHandler 
 */
public class ButtonObj {

    /**
     * The Calculator-adaptor that this instance can use to get and
     * set text.  Initialized in constructor; shouldn't change.
     */
  protected CalcTextGUI gui;

    /**
     * The CalculatorState that keeps track of what's going on in the
     * behavior of the Calculator that this ButtonObj belongs to.
     * Initialized in constructor; shouldn't change.
     */
  protected CalculatorState stateObj;

  /**
   * How to make one: tell it what GUI and what state object it's
   * working with.  It will remember these for future use.
   *
   * @param gui      The CalcTextGUI to keep track of.
   * @param stateObj The CalculatorState to keep track of.
   */
  public ButtonObj( CalcTextGUI gui, CalculatorState stateObj ) {
    this.gui = gui;
    this.stateObj = stateObj;
  }

    /**
     * How to handle a button.  (In this case, don't do much.
     * Subclasses will override.)
     */
  public void handleButton(){}

}



/*
 * $Log: ButtonObj.java,v $
 * Revision 1.1.1.1  2002/06/05 21:56:25  root
 * CS101 comes to Olin finally.
 *
 * Revision 1.3  1997/10/30 03:28:35  lfgs
 * Added overview and fixed "* /" commenting typo in code.
 *
 * Revision 1.2  1997/10/24 22:20:41  las
 * Documented all of the code files, but didn't write the user manual (yet).
 *
 */