ImagePrinter.java 文件源码

public int print(Graphics g, PageFormat pf, int index) {

        if (index > 0 || image == null) {
            return Printable.NO_SUCH_PAGE;
        }

        ((Graphics2D)g).translate(pf.getImageableX(), pf.getImageableY());
        int w = image.getWidth(null);
        int h = image.getHeight(null);
        int iw = (int)pf.getImageableWidth();
        int ih = (int)pf.getImageableHeight();

        // ensure image will fit
        int dw = w;
        int dh = h;
        if (dw > iw) {
            dh = (int)(dh * ( (float) iw / (float) dw)) ;
            dw = iw;
        }
        if (dh > ih) {
            dw = (int)(dw * ( (float) ih / (float) dh)) ;
            dh = ih;
        }
        // centre on page
        int dx = (iw - dw) / 2;
        int dy = (ih - dh) / 2;

        g.drawImage(image, dx, dy, dx+dw, dy+dh, 0, 0, w, h, null);
        return Printable.PAGE_EXISTS;
    }