ChatGPTに作ってもらった時計

ClockPanel.java

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

class ClockPanel extends JPanel {

    private final Timer timer;
    private final int DELAY = 1000; // 1秒ごとに更新
    private Point initialClick;  // ドラッグの開始地点を保存する

    public ClockPanel() {
        timer = new Timer(DELAY, ae -> repaint());
        timer.start();
        addMouseListener(new MouseAdapter() {
            @Override
            public void mousePressed(MouseEvent e) {
                initialClick = e.getPoint();
                getComponentAt(initialClick);
            }
        });
        addMouseMotionListener(new MouseMotionAdapter() {
            @Override
            public void mouseDragged(MouseEvent e) {
                // ドラッグ中にウィンドウの位置を更新
                int thisX = getTopLevelAncestor().getLocation().x;
                int thisY = getTopLevelAncestor().getLocation().y;

                // Determine how much the mouse moved since the initial click
                int xMoved = e.getX() - initialClick.x;
                int yMoved = e.getY() - initialClick.y;

                // Move window to this position
                int X = thisX + xMoved;
                int Y = thisY + yMoved;
                getTopLevelAncestor().setLocation(X, Y);
            }
        });
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        drawClock(g);
    }

    private void drawMinuteMarks(Graphics g, int x, int y, int minute, double length) {
        double angle = Math.toRadians(-minute * 6 + 90); // 描画のための角度を調整
        int endX = x + (int) (length * Math.cos(angle));
        int endY = y - (int) (length * Math.sin(angle));

        g.setColor(Color.BLACK);
        if (minute % 5 == 0) {  // 5の倍数であるかどうかを確認
            g.fillOval(endX - 4, endY - 4, 8, 8);  // 5分ごとの点の大きさを8x8にする
        } else {
            g.fillOval(endX - 2, endY - 2, 4, 4);  // 通常の1分ごとの点の大きさを4x4にする
        }
    }

    private void drawClock(Graphics g) {
        int centerX = getWidth() / 2;
        int centerY = getHeight() / 2;
        int clockRadius = Math.min(centerX, centerY) - 10;

        Calendar now = Calendar.getInstance();
        int hour = now.get(Calendar.HOUR);
        int minute = now.get(Calendar.MINUTE);
        int second = now.get(Calendar.SECOND);

        // 時針
        drawHand(g, centerX, centerY, hour % 12 * 30 + minute * 0.5, clockRadius * 0.5, 6);

        // 分針
        drawHand(g, centerX, centerY, minute * 6 + second * 0.1, clockRadius * 0.65, 4);

        // 秒針
        drawHand(g, centerX, centerY, second * 6, clockRadius * 0.75, 2);

        // 中心の点
        g.setColor(Color.BLACK);
        g.fillOval(centerX - 3, centerY - 3, 6, 6);

        // 1分ごとの点 (5分ごとに強調)
        for (int i = 0; i < 60; i++) {
            drawMinuteMarks(g, centerX, centerY, i, clockRadius * 0.92);  // 0.92は点を描く位置の半径を調整するための係数
        }
    }

    private void drawHand(Graphics g, int x, int y, double angle, double length, int thickness) {
        angle = Math.toRadians(-angle + 90);
        int endX = x + (int) (length * Math.cos(angle));
        int endY = y - (int) (length * Math.sin(angle));

        Graphics2D g2d = (Graphics2D) g;
        g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
        g2d.setStroke(new BasicStroke(thickness, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
        g2d.drawLine(x, y, endX, endY);
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame("アナログ時計");
        ClockPanel clockPanel = new ClockPanel();
        frame.setUndecorated(true); // タイトルバーを消す
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(400, 400);
        frame.setLayout(new BorderLayout());
        frame.add(clockPanel, BorderLayout.CENTER);
        frame.setVisible(true);
    }
}

アンチエイリアスかけてもらった