src/main/java/org/jfree/graphics2d/GraphicsUtils.java
public static Shape copyOf(Shape shape) {
       Args.nullNotPermitted(shape, "shape");
       if (shape instanceof Line2D) {
           Line2D l = (Line2D) shape;
           return new Line2D.Double(l.getX1(), l.getY1(), l.getX2(), l.getY2());
       }
       if (shape instanceof Rectangle2D) {
           Rectangle2D r = (Rectangle2D) shape;
           return new Rectangle2D.Double(r.getX(), r.getY(), r.getWidth(), 
                   r.getHeight());
       }
       if (shape instanceof RoundRectangle2D) {
           RoundRectangle2D rr = (RoundRectangle2D) shape;
           return new RoundRectangle2D.Double(rr.getX(), rr.getY(), 
                   rr.getWidth(), rr.getHeight(), rr.getArcWidth(), 
                   rr.getArcHeight());
       }
       if (shape instanceof Arc2D) {
           Arc2D arc = (Arc2D) shape;
           return new Arc2D.Double(arc.getX(), arc.getY(), arc.getWidth(),
                   arc.getHeight(), arc.getAngleStart(), arc.getAngleExtent(),
                   arc.getArcType());
       }
       if (shape instanceof Ellipse2D) {
           Ellipse2D ell = (Ellipse2D) shape;
           return new Ellipse2D.Double(ell.getX(), ell.getY(), ell.getWidth(),
                   ell.getHeight());
       }
       if (shape instanceof Polygon) {
           Polygon p = (Polygon) shape;
           return new Polygon(p.xpoints, p.ypoints, p.npoints);
       }
       return new Path2D.Double(shape);
    }
public static Shape copyOf(Shape shape) {
       Args.nullNotPermitted(shape, "shape");
       if (shape instanceof Line2D) {
           Line2D l = (Line2D) shape;
           return new Line2D.Double(l.getX1(), l.getY1(), l.getX2(), l.getY2());
       }
       if (shape instanceof Rectangle2D) {
           Rectangle2D r = (Rectangle2D) shape;
           return new Rectangle2D.Double(r.getX(), r.getY(), r.getWidth(), 
                   r.getHeight());
       }
       if (shape instanceof RoundRectangle2D) {
           RoundRectangle2D rr = (RoundRectangle2D) shape;
           return new RoundRectangle2D.Double(rr.getX(), rr.getY(), 
                   rr.getWidth(), rr.getHeight(), rr.getArcWidth(), 
                   rr.getArcHeight());
       }
       if (shape instanceof Arc2D) {
           Arc2D arc = (Arc2D) shape;
           return new Arc2D.Double(arc.getX(), arc.getY(), arc.getWidth(),
                   arc.getHeight(), arc.getAngleStart(), arc.getAngleExtent(),
                   arc.getArcType());
       }
       if (shape instanceof Ellipse2D) {
           Ellipse2D ell = (Ellipse2D) shape;
           return new Ellipse2D.Double(ell.getX(), ell.getY(), ell.getWidth(),
                   ell.getHeight());
       }
       if (shape instanceof Polygon) {
           Polygon p = (Polygon) shape;
           return new Polygon(p.xpoints, p.ypoints, p.npoints);
       }
       return new Path2D.Double(shape);
    }
Returns a shape that is (more or less) equivalent to the supplied shape.
For some known shape implementations ({@code Line2D},
{@code Rectangle2D}, {@code RoundRectangle2D}, {@code Arc2D},
{@code Ellipse2D}, and {@code Polygon}) the copy will be an instance of
that class.  For other shapes, a {@code Path2D} containing the outline
of the shape is returned.

@param shape  the shape ({@code null} not permitted).

@return A copy of the shape or shape outline (never {@code null}).