KonjicevSkok

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class KonjicevSkok extends JFrame {

    private ChessField[][] board = new ChessField[8][8];
    private Icon knightIcon = new ImageIcon("konjic.png");
    private ChessField knight;

    private class ChessField extends JPanel {
        private JLabel label;
        private int x, y;

        public ChessField(Color color, int x, int y) {
            this.x = x;
            this.y = y;
            setBackground(color);
            label = new JLabel();
            setLayout(new BorderLayout());
            add(label);

            addMouseListener(
                new MouseAdapter() {
                    @Override
                    public void mouseClicked(MouseEvent arg0) {
                        move();
                    }
                }
            );
        }

        private void move() {
            int xDiff = Math.abs(x - knight.x);
            int yDiff = Math.abs(y - knight.y);

            if ((xDiff == 1 && yDiff == 2) || (xDiff == 2 && yDiff == 1)) {
                knight.reset();
                knight.setVisited();
                knight = this;
                setKnight();
            }
        }

        public void setKnight() {
            label.setIcon(knightIcon);
        }

        public void reset() {
            label.setIcon(null);
        }

        public void setVisited() {
            setBackground(Color.GREEN);
        }
    }

    public KonjicevSkok() {
        JPanel chessBoard = new JPanel();
        chessBoard.setLayout(new GridLayout(8, 8));

        for (int i = 0; i < 8; i++) {
            for (int j = 0; j < 8; j++) {
                boolean gray = (i + j) % 2 == 1;
                ChessField f = null;
                if (gray) {
                    f = new ChessField(Color.GRAY, i, j);
                } else {
                    f = new ChessField(Color.WHITE, i, j);
                }
                board[i][j] = f;

                if (i == 0 && j == 0) {
                    f.setKnight();
                    knight = f;
                }

                chessBoard.add(f);
            }
        }

        Container c = getContentPane();
        c.add(chessBoard);
    }

    public static void main(String[] args) {
        KonjicevSkok g = new KonjicevSkok();
        g.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        g.setSize(400, 400);
        g.setTitle("Konjicev skok");
        g.setVisible(true);
    }
}