java_wejsciowka_eventy

// importy

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

// main
public class Aplikacja {

    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(() -> {
            JFrame okno = new JFrame("Aplikacja");

            okno.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            okno.setContentPane(new ZdarzeniaMysz()); // okno.setContentPane(new ZdarzeniaKlawiatura());

            okno.setBounds(100, 50, 300, 150);
            okno.setVisible(true);
        });
    }
}

// mysz

public class ZdarzeniaMysz extends JPanel {

    final int SREDNICA = 24;
    int koloX;
    int koloY;

    public ZdarzeniaMysz() {
        addMouseListener(new ObslugaMysz());
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        g.setColor(Color.RED);
        g.fillOval(koloX, koloY, SREDNICA, SREDNICA);
    }

    class ObslugaMysz implements MouseListener {

        @Override
        public void mousePressed(MouseEvent me) {
        }

        @Override
        public void mouseReleased(MouseEvent me) {
        }

        @Override
        public void mouseEntered(MouseEvent me) {
        }

        @Override
        public void mouseExited(MouseEvent me) {
        }

        @Override
        public void mouseClicked(MouseEvent me) {
            koloX = me.getX() - SREDNICA/2;
            koloY = me.getY() - SREDNICA/2;

            repaint();
        }

    }
}

// klawiatura

public class ZdarzeniaKlawiatura extends JPanel {

    final int SREDNICA = 24;
    int koloX;
    int koloY;

    public ZdarzeniaKlawiatura() {
        setFocusable(true);
        addKeyListener(new ObslugaKlawiatura());
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        g.setColor(Color.RED);
        g.fillOval(koloX, koloY, SREDNICA, SREDNICA);
    }

    class ObslugaKlawiatura implements KeyListener {

        @Override
        public void keyReleased(KeyEvent ke) {
        }

        @Override
        public void keyTyped(KeyEvent ke) {
        }

        @Override
        public void keyPressed(KeyEvent ke) {

            switch(ke.getKeyCode()) {
                case KeyEvent.VK_DOWN: koloY += 5; break;
                case KeyEvent.VK_UP: koloY -= 5; break;
                case KeyEvent.VK_LEFT: koloX -= 5; break;
                case KeyEvent.VK_RIGHT: koloX += 5; break;
            }
            repaint();

        }

    }
}