cursor-sandbox

import java.awt.Cursor;
import java.awt.Point;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;

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

import com.sun.jna.Pointer;

/**
 * Taken from
 * https://stackoverflow.com/questions/739870/extract-cursor-image-in-java/740528
 */
class CursorExtractor {

    private static void draw(BufferedImage image, int cursor,
                             int diFlags) {
        int width = image.getWidth();
        int height = image.getHeight();

        User32 user32 = User32.INSTANCE;
        Gdi32 gdi32 = Gdi32.INSTANCE;

        Pointer hIcon = user32
                .LoadCursorW(Pointer.NULL, cursor);
        Pointer hdc = gdi32.CreateCompatibleDC(Pointer.NULL);
        Pointer bitmap = gdi32.CreateCompatibleBitmap(hdc,
                width, height);

        gdi32.SelectObject(hdc, bitmap);
        user32.DrawIconEx(hdc, 0, 0, hIcon, 0, 0, 0,
                Pointer.NULL, diFlags);

        for (int x = 0; x < width; x++) {
            for (int y = 0; y < width; y++) {
                int rgb = gdi32.GetPixel(hdc, x, y);
                image.setRGB(x, y, rgb);
            }
        }

        gdi32.DeleteObject(bitmap);
        gdi32.DeleteDC(hdc);
    }


    public static void main(String[] args) {

        BufferedImage image = getCursor(User32.IDC_ARROW);

        JLabel icon = new JLabel();
        icon.setIcon(new ImageIcon(image));

        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setContentPane(icon);
        frame.pack();
        frame.setVisible(true);

        Toolkit toolkit = Toolkit.getDefaultToolkit();
        Point pointerPos = new Point(1, 1);
        Cursor c = toolkit.createCustomCursor(image, pointerPos, "cursorname");
        frame.setCursor(c);
    }


    public static BufferedImage getCursor(int cursorType) {
        final int width = User32.INSTANCE.GetSystemMetrics(User32.SM_CXCURSOR);
        final int height = User32.INSTANCE.GetSystemMetrics(User32.SM_CYCURSOR);

        System.out.println(String.format("Cursor height: %d, Cursor weight: %d", height, width));

        BufferedImage image = new BufferedImage(width, height,
                BufferedImage.TYPE_INT_ARGB);
        draw(image, cursorType, User32.DI_NORMAL);
        BufferedImage mask = new BufferedImage(width, height,
                BufferedImage.TYPE_INT_RGB);
        draw(mask, cursorType, User32.DI_MASK);
        applyMask(image, mask);
        return image;
    }

    private static void applyMask(BufferedImage image,
                                  BufferedImage mask) {
        int width = image.getWidth();
        int height = image.getHeight();
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                int masked = mask.getRGB(x, y);
                if ((masked & 0x00FFFFFF) == 0) {
                    int rgb = image.getRGB(x, y);
                    rgb = 0xFF000000 | rgb;
                    image.setRGB(x, y, rgb);
                }
            }
        }
    }

}