问鼠标悬停在曲线上

EN

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;

import javax.swing.JFrame;


public class Test extends Canvas implements MouseMotionListener {

    private JFrame frame;
    private CubicCurve2D curve;
    private static final int OFFSET = 1000;

    public Test() {
        frame = new JFrame();

        addMouseMotionListener(this);
        setPreferredSize(new Dimension(800, 600));
        setBackground(Color.WHITE);

        frame.add(this);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
    }

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

        Graphics2D g2 = (Graphics2D) g;

        curve = new CubicCurve2D.Double(10, 100, 700, -500
                + Math.random() * OFFSET, -500 + Math.random() * OFFSET, 700,
                590, 500);

        g2.setPaint(Color.RED);
        g2.setStroke(new BasicStroke(2));
        g2.draw(curve);

        g2.setPaint(Color.lightGray);
        g2.fill(curve);
    }

    @Override
    public void mouseMoved(MouseEvent e) {
        System.out.println(curve.contains(e.getX(), e.getY()));
    }

    @Override
    public void mouseDragged(MouseEvent e) {}

    public static void main(String[] args) {
        new Test();
    }

}