Embedded Files
Introduction
Introduction
In this activity, you will complete a Card class that will be used to create card objects.
Think about card games you’ve played. What kinds of information do these games require a card object to
“know”? What kinds of operations do these games require a card object to provide?
Exploration:
Exploration:
Now think about implementing a class to represent a playing card. What instance variables should it have? What methods should it provide? Discuss your ideas for this Card class with classmates.
Read the partial implementation of the Card class available in the Activity1 Starter Code folder. As you read through this class, you will notice the use of the @Override annotation before the toString method. The Java @Override annotation can be used to indicate that a method is intended to override a method in a superclass. In this example, the Object class’s toString method is being overridden in the Card class. If the indicated method doesn’t override a method, then the Java compiler will give an error message.
Here’s a situation where this facility comes in handy. Programmers new to Java often encounter problems matching headings of overridden methods to the superclass’s original method heading. For example, in the Weight class below, the tostring method is intended to be invoked when toString is called for a Weight object.
Unfortunately, this doesn't work; the tostring method given above has a different name and a different signature from the Object class’s toString method. The correct version below has the correct name toString and no parameter:
The @Override annotation would cause an error message for the first tostring version to alert the programmer of the errors.
Exercises
Exercises
- Complete the implementation of the provided Card class. You will be required to complete:
- a constructor that takes two String parameters that represent the card’s rank and suit, and an int
- parameter that represents the point value of the card;
- accessor methods for the card’s rank, suit, and point value;
- a method to test equality between two card objects; and
- the toString method to create a String that contains the rank, suit, and point value of the card object. The string should be in the following format:
- rank of suit (point value = pointValue)
- Create three Card objects and test each method for each Card object.
Card.java
Card.java
/** * Card.java * * <code>Card</code> represents a playing card. */public class Card { /** * String value that holds the suit of the card */ private String suit; /** * String value that holds the rank of the card */ private String rank; /** * int value that holds the point value. */ private int pointValue; /** * Creates a new <code>Card</code> instance. * * @param cardRank a <code>String</code> value * containing the rank of the card * @param cardSuit a <code>String</code> value * containing the suit of the card * @param cardPointValue an <code>int</code> value * containing the point value of the card */ public Card(String cardRank, String cardSuit, int cardPointValue) { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ } /** * Accesses this <code>Card's</code> suit. * @return this <code>Card's</code> suit. */ public String suit() { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ } /** * Accesses this <code>Card's</code> rank. * @return this <code>Card's</code> rank. */ public String rank() { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ } /** * Accesses this <code>Card's</code> point value. * @return this <code>Card's</code> point value. */ public int pointValue() { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ } /** Compare this card with the argument. * @param otherCard the other card to compare to this * @return true if the rank, suit, and point value of this card * are equal to those of the argument; * false otherwise. */ public boolean matches(Card otherCard) { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ } /** * Converts the rank, suit, and point value into a string in the format * "[Rank] of [Suit] (point value = [PointValue])". * This provides a useful way of printing the contents * of a <code>Deck</code> in an easily readable format or performing * other similar functions. * * @return a <code>String</code> containing the rank, suit, * and point value of the card. */ @Override public String toString() { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ }}CardTester
CardTester
/** * This is a class that tests the Card class. */public class CardTester { /** * The main method in this class checks the Card operations for consistency. * @param args is not used. */ public static void main(String[] args) { /* *** TO BE IMPLEMENTED IN ACTIVITY 1 *** */ }}Report abuse