не могу найти описание

package com.javarush.games.snake; import com.javarush.engine.cell.*; import java.util.*; public class SnakeGame extends Game { public static final int WIDTH = 15; public static final int HEIGHT = 15; private Snake snake; private int turnDelay; private Apple apple; private boolean isGameStopped; private static final int GOAL = 28; private int score; @Override public void initialize(){ setScreenSize(WIDTH,HEIGHT); createGame(); } @Override public void onTurn(int x){ snake.move(apple); if(!snake.isAlive){ gameOver(); } if(snake.getLength() > GOAL){ win(); } if(!apple.isAlive){ score = score + 5; setScore(score); turnDelay = turnDelay - 10; setTurnTimer(turnDelay); } drawScene(); } @Override public void onKeyPress(Key key) { if (key == Key.SPACE && isGameStopped == true) createGame(); if(key==Key.LEFT){ snake.setDirection(Direction.LEFT); } if(key==Key.RIGHT){ snake.setDirection(Direction.RIGHT); } if(key==Key.UP){ snake.setDirection(Direction.UP); } if(key==Key.DOWN){ snake.setDirection(Direction.DOWN); } } private void createGame(){ snake = new Snake ( WIDTH / 2, HEIGHT / 2 ); createNewApple(); isGameStopped=false; drawScene(); snake.draw(this); turnDelay= 300; setTurnTimer( turnDelay) ; score = 0; setScore(score); } private void drawScene() { for (int x = 0; x < WIDTH; x++) { for (int y = 0; y < HEIGHT; y++) { setCellValueEx(x, y, Color.DARKSEAGREEN, ""); } } snake.draw(this); apple.draw(this); } private void createNewApple(){ { do { apple = new Apple(getRandomNumber(WIDTH), getRandomNumber(HEIGHT)); } while (snake.checkCollision(apple)); } } private void gameOver(){ stopTurnTimer(); isGameStopped = true; this.showMessageDialog(Color.BLACK, "Game Over", Color.RED, 75); } private void win(){ stopTurnTimer(); isGameStopped = true; showMessageDialog(Color.RED,"***YOU WIN***", Color.YELLOW, 75); } }