我刚接触java开发,我可以使用文件选择器将图像插入数据库,然后转换为字节,问题是我想将默认图像保存到数据库而不使用文件选择器。我设置标签通过属性的特定图像。我可以将我设置的默认图像转换为标签吗?
任何帮助将不胜感激。
答案 0 :(得分:0)
是的,这是可能的。您需要将Icon
从JLabel
转换为BufferedImage
,然后您可以通过ImageIO
API将其传递给byte[]
数组
Icon icon = null;
BufferedImage img = new BufferedImage(icon.getIconWidth(), icon.getIconHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g2d = img.createGraphics();
icon.paintIcon(null, g2d, 0, 0);
g2d.dispose();
try (ByteArrayOutputStream baos = new ByteArrayOutputStream()) {
ImageOutputStream ios = ImageIO.createImageOutputStream(baos);
try {
ImageIO.write(img, "png", ios);
// Set a flag to indicate that the write was successful
} finally {
ios.close();
}
byte[] bytes = baos.toByteArray();
} catch (IOException ex) {
ex.printStackTrace();
}
答案 1 :(得分:0)
我的项目零件代码:
..........
BufferedImage bfi = getBufferedImage(iconToImage(my_Jlabel.getIcon()));
ByteArrayOutputStream bs = new ByteArrayOutputStream();
ImageIO.write(bfi, "png", bs);
byte[] byteArray = bs.toByteArray();
pstmt.setBytes(17, byteArray);
.............
public static BufferedImage getBufferedImage(Image img){
if (img instanceof BufferedImage)
{
return (BufferedImage) img;
}
BufferedImage bimage = new BufferedImage(img.getWidth(null),
img.getHeight(null), BufferedImage.TYPE_INT_ARGB);
Graphics2D bGr = bimage.createGraphics();
bGr.drawImage(img, 0, 0, null);
bGr.dispose();
return bimage;
}
static Image iconToImage(Icon icon) {
if (icon instanceof ImageIcon) {
return ((ImageIcon)icon).getImage();
}
else {
int w = icon.getIconWidth();
int h = icon.getIconHeight();
GraphicsEnvironment ge =
GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice gd = ge.getDefaultScreenDevice();
GraphicsConfiguration gc = gd.getDefaultConfiguration();
BufferedImage image = gc.createCompatibleImage(w, h);
Graphics2D g = image.createGraphics();
icon.paintIcon(null, g, 0, 0);
g.dispose();
return image;
}
}