teaching machines

CS 145 Lecture 20 – NDeckerBurger, our first object

April 20, 2012 by Chris Johnson. Filed under cs145, lectures, spring 2012.

Agenda

• objects
• instance variables
• constructors
• methods
• static vs. instance

Code

NDeckerBurger.java

package prefinal;

public class NDeckerBurger {
  private int nDecks;
  private boolean hasCheese;

  public static final int CALORIES_PER_DECK = 211;

  public NDeckerBurger(int givenDeckCount) {
    nDecks = givenDeckCount;
  }

  public NDeckerBurger(int givenDeckCount, boolean hasCheese) {
    nDecks = givenDeckCount;
    this.hasCheese = hasCheese;
  }

  public int getDeckCount() {
    return nDecks;
  }

  public int getPickleCount() {
    return 3 * nDecks;
  }

  public int getCheeseCount() {
    if (hasCheese) {
      return 1 * nDecks;
    } else {
      return 0;
    }
  }

  public int getBunCount() {
    return nDecks + 1;
  }

  public int getKetchupOunces() {
    return nDecks;
  }

  public int getBaconCount() {
    return 3 * nDecks;
  }

  public double getCalorieCount() {
    return CALORIES_PER_DECK * getDeckCount() +
        31 * getCheeseCount() +
        10 * getPickleCount() +
        27 * getBunCount() +
        41 * getBaconCount() +
        10 * getKetchupOunces() / 0.4;
  }
}

Restaurant.java

package prefinal;

public class Restaurant {
  public static void main(String[] args) {
    NDeckerBurger myBreakfast = new NDeckerBurger(7);
//    myBreakfast.nDecks = 7;

    NDeckerBurger yourBreakfast = new NDeckerBurger(3);
//    yourBreakfast.nDecks = 3;

    System.out.println(myBreakfast.getDeckCount());

    System.out.println(myBreakfast.getCalorieCount());
    System.out.println(yourBreakfast.getCalorieCount());

    System.out.println(NDeckerBurger.CALORIES_PER_DECK);

    // ILL-EGAL. getDeckCount is not static.
//    System.out.println(NDeckerBurger.getDeckCount());
  }
}