Playground.java

import java.util.Arrays;
import java.util.Iterator;

class Playground implements Iterable {
	int[][] field;
	int xSize;
	int ySize;
	private int generation;
	
	public Playground(int xSize, int ySize, int generation) {
		this.xSize = xSize;
		this.ySize = ySize;
		field = new int[xSize][ySize];
		for(int i = 0; i < xSize; i++) {
			field[i] = new int[ySize];
			Arrays.fill(field[i], 0);
		}
		this.generation = generation;
	}
		
	public void set(int x, int y, int value) {
		field[x][y] = value;
	}
	
	public int getXSize() {
		return xSize;
	}
	
	public int getYSize() {
		return ySize;
	}
	
	public int getGeneration() {
		return generation;
	}
	
	public int[][] getField() {
		int[][] result = new int[field.length][];
		for(int i = 0; i < field.length; i++) {
			result[i] = new int[field[i].length];
			System.arraycopy(field[i], 0, result[i], 0, field[i].length);
		}
		return result;
	}
	
	int[] getNeighbourhood(int x, int y) {
		/*   v
		 * . . .
		 * . . .     <
		 * . . .
		 */
		int xCurrent = x - 1;
		int yCurrent = y - 1;
		int[] result = new int[8];
		for(int i = 0; i < 8; i++) {
			if(xCurrent < 0 || xCurrent >= xSize || yCurrent < 0 || yCurrent >= ySize) {
				result[i] = 0;
			} else {
				result[i] = field[xCurrent][yCurrent];
			}
			xCurrent++;
			if (xCurrent > x + 1) {
				xCurrent = x - 1;
				yCurrent++;
			}
			if(xCurrent == x && yCurrent == y) {
				xCurrent++;
			}
		}
		return result;
	}
	
	public Iterator iterator() {
		return new LifeFormIterator(this);
	}
}