我需要將 JPanel（圖形）中的內容（形狀）轉換為 SVGGraphics2D 對象，以獲取使用 Apache Batik 庫生成的 svg 文件。public void paintComponent(Graphics g) {    Graphics2D g2 = (Graphics2D) g;    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,             RenderingHints.VALUE_ANTIALIAS_ON);    g2.setPaint(fg);    // draw Text    g2.drawString("Hello world!", 250, 400);    // draw Line2D.Double    g2.setPaint(orange);    g2.draw(new Line2D.Double(50, 50, 200, 200));    // draw Point2D.Double    g2.setPaint(red);    g2.fill(new Ellipse2D.Double(400, 400, 5, 5));    // draw Rectangle2D.Double    g2.setPaint(magenta);    g2.draw(new Rectangle2D.Double(600, 600, 300, 150));    g2.setPaint(magenta);    g2.draw(new Rectangle2D.Double(300, 300, 300, 150));    // draw Ellipse2D.Double    g2.setPaint(blue);    g2.draw(new Ellipse2D.Double(400, 400, 200, 200));    // draw GeneralPath (polygon)    g2.setPaint(green);    int x1Points[] = {200, 500, 300};    int y1Points[] = {100, 100, 300};    GeneralPath polygon = new GeneralPath(GeneralPath.WIND_EVEN_ODD,             x1Points.length);    polygon.moveTo(x1Points[0], y1Points[0]);    for ( int index = 1; index < x1Points.length; index++ ) {        polygon.lineTo(x1Points[index], y1Points[index]);    }    polygon.closePath();    g2.draw(polygon);}public void onlyWrite(){    JFrame f = new JFrame("Shapes Example2");    f.addWindowListener(new WindowAdapter() {        public void windowClosing(WindowEvent e) {System.exit(0);}    });    // Get a DOMImplementation.    DOMImplementation domImpl = GenericDOMImplementation.getDOMImplementation();鑄造 SVGGraphics2D 我得到以下異常：線程“main”中的異常 java.lang.ClassCastException: sun.java2d.SunGraphics2D 無法在 ShapesExample2.onlyWrite(ShapesExample2.java:122) at ShapesExample2.main(ShapesExample2.java: 144)我怎樣才能得到 svg 文件？謝謝！