public class Field
{
 private final int width;
 private final int height;
 private final Cell[][] field;
 private final int[][] neighbours;

 public Field(int width, int height)
 {
 this.width = width;
 this.height = height;
 field = new Cell[height][width];
 neighbours = new int[height][width];

 for (int row = 0; row < height; row++)
 {
 for (int col = 0; col < width; col++)
 {
 field[row][col] = new Cell();
 if (Math.random() < 0.2)
 {
 field[row][col].setAlive(true);
 }
 }
 }
 }

 public int getWidth()
 {
 return width;
 }

 public int getHeight()
 {
 return height;
 }

 public boolean isAlive(int row, int col)
 {
 if (row < 0 || row >= height || col < 0 || col >= width)
 {
 return false;
 }
 return field[row][col].isAlive();
 }

 public int getNeighbour(int row, int col)
 {
 int cnt = 0;
 for (int r = row - 1; r <= row + 1; r++)
 {
 for (int c = col - 1; c <= col + 1; c++)
 {
 if (!(r == row && c == col) && isAlive(r, c))
 {
 cnt++;
 }
 }
 }
 return cnt;
 }

 public void update()
 {
 for (int row = 0; row < height; row++)
 {
 for (int col = 0; col < width; col++)
 {
 neighbours[row][col] = getNeighbour(row, col);
 }
 }

 for (int row = 0; row < height; row++)
 {
 for (int col = 0; col < width; col++)
 {
 field[row][col].update(neighbours[row][col]);
 }
 }
 }
}