Tile.java

import java.util.Random;
import java.util.ArrayList;

/**
 * A tile in the game of Concentration, i
 * Tiles are arranged on an n x m board, represented in a 2-dim array
 * 
 * In this version, a tile contains a card, similar to a playing card. Cards
 * have string values for their "face up" and "face down" state. Each tile
 * is shown face up or face down on the board.
 * 
 * A tile can also have a "cardMatched", indicateing the card has been matched
 * with another card and has been removed from the board. We use this value 
 * instead of a blank value or a missing tile because it helps to represent
 * the m x n game board when tiles would otherwise be blank or missing.
 * 
 */
public class Tile
{
 private boolean faceUp;
 private boolean matched;
 private String cardFace; 
 private String cardBack = "_____";
 private String cardMatched = " * ";
 
 /**
 * Construct a tile with a string value. The default state
 * of a tile is unmatched and face down on the board.
 * 
 * @param word the word that represents the card face
 */
 public Tile(String word) 
 {
 cardFace = word;
 }
 
 /**
 * Return the value of the tile in its face up state
 * 
 * @return faceUp 
 */
 public String getFace() {
 return cardFace;
 }
 
 /**
 * Return the value of the tile in its face down state
 * 
 * @return the face (as a String value)
 */
 public String getBack() {
 return cardBack;
 }
 
 /**
 * Set the card to either a face up or face down state
 * 
 * @param b set to true to show the card face up, set to false to show face down
 */
 public void faceUp(boolean b)
 {
 faceUp = b;
 }
 
 /**
 * Determine if the card is currently face up
 * 
 * @return true if the card is currently in the faceUp state, false otherwise
 */
 public boolean isFaceUp() {
 return faceUp;
 }
 
 /**
 * A matching pair of cards has been found, set matched to true
 * and change the way the card is shown 
 */
 public void foundMatch() {
 matched = true;
 cardFace = cardMatched;
 cardBack = cardMatched;
 }
 
 /**
 * Determine if this tile has been matched
 * 
 * @return true of the card was previously matched, false otherwise
 */
 public boolean matched() {
 return matched;
 }

 @Override
 public boolean equals(Object obj) {
 if (obj instanceof Tile) {
 Tile otherTile = (Tile)obj;
 return cardFace.equals(otherTile.getFace());
 } else {
 return false;
 }
 }
}